includes/OutputPage.php

   1 <?php
   2 /**
   3  * Preparation for the final page rendering.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 use MediaWiki\Linker\LinkTarget;
  24 use MediaWiki\Logger\LoggerFactory;
  25 use MediaWiki\MediaWikiServices;
  26 use MediaWiki\Session\SessionManager;
  27 use Wikimedia\Rdbms\IResultWrapper;
  28 use Wikimedia\RelPath;
  29 use Wikimedia\WrappedString;
  30 use Wikimedia\WrappedStringList;
  31
  32 /**
  33  * This class should be covered by a general architecture document which does
  34  * not exist as of January 2011.  This is one of the Core classes and should
  35  * be read at least once by any new developers.
  36  *
  37  * This class is used to prepare the final rendering. A skin is then
  38  * applied to the output parameters (links, javascript, html, categories ...).
  39  *
  40  * @todo FIXME: Another class handles sending the whole page to the client.
  41  *
  42  * Some comments comes from a pairing session between Zak Greant and Antoine Musso
  43  * in November 2010.
  44  *
  45  * @todo document
  46  */
  47 class OutputPage extends ContextSource {
  48         /** @var array Should be private. Used with addMeta() which adds "<meta>" */
  49         protected $mMetatags = [];
  50
  51         /** @var array */
  52         protected $mLinktags = [];
  53
  54         /** @var bool */
  55         protected $mCanonicalUrl = false;
  56
  57         /**
  58          * @var string The contents of <h1> */
  59         private $mPageTitle = '';
  60
  61         /**
  62          * @var string Contains all of the "<body>" content. Should be private we
  63          *   got set/get accessors and the append() method.
  64          */
  65         public $mBodytext = '';
  66
  67         /** @var string Stores contents of "<title>" tag */
  68         private $mHTMLtitle = '';
  69
  70         /**
  71          * @var bool Is the displayed content related to the source of the
  72          *   corresponding wiki article.
  73          */
  74         private $mIsArticle = false;
  75
  76         /** @var bool Stores "article flag" toggle. */
  77         private $mIsArticleRelated = true;
  78
  79         /**
  80          * @var bool We have to set isPrintable(). Some pages should
  81          * never be printed (ex: redirections).
  82          */
  83         private $mPrintable = false;
  84
  85         /**
  86          * @var array Contains the page subtitle. Special pages usually have some
  87          *   links here. Don't confuse with site subtitle added by skins.
  88          */
  89         private $mSubtitle = [];
  90
  91         /** @var string */
  92         public $mRedirect = '';
  93
  94         /** @var int */
  95         protected $mStatusCode;
  96
  97         /**
  98          * @var string Used for sending cache control.
  99          *   The whole caching system should probably be moved into its own class.
 100          */
 101         protected $mLastModified = '';
 102
 103         /** @var array */
 104         protected $mCategoryLinks = [];
 105
 106         /** @var array */
 107         protected $mCategories = [
 108                 'hidden' => [],
 109                 'normal' => [],
 110         ];
 111
 112         /** @var array */
 113         protected $mIndicators = [];
 114
 115         /** @var array Array of Interwiki Prefixed (non DB key) Titles (e.g. 'fr:Test page') */
 116         private $mLanguageLinks = [];
 117
 118         /**
 119          * Used for JavaScript (predates ResourceLoader)
 120          * @todo We should split JS / CSS.
 121          * mScripts content is inserted as is in "<head>" by Skin. This might
 122          * contain either a link to a stylesheet or inline CSS.
 123          */
 124         private $mScripts = '';
 125
 126         /** @var string Inline CSS styles. Use addInlineStyle() sparingly */
 127         protected $mInlineStyles = '';
 128
 129         /**
 130          * @var string Used by skin template.
 131          * Example: $tpl->set( 'displaytitle', $out->mPageLinkTitle );
 132          */
 133         public $mPageLinkTitle = '';
 134
 135         /** @var array Array of elements in "<head>". Parser might add its own headers! */
 136         protected $mHeadItems = [];
 137
 138         /** @var array Additional <body> classes; there are also <body> classes from other sources */
 139         protected $mAdditionalBodyClasses = [];
 140
 141         /** @var array */
 142         protected $mModules = [];
 143
 144         /** @var array */
 145         protected $mModuleScripts = [];
 146
 147         /** @var array */
 148         protected $mModuleStyles = [];
 149
 150         /** @var ResourceLoader */
 151         protected $mResourceLoader;
 152
 153         /** @var ResourceLoaderClientHtml */
 154         private $rlClient;
 155
 156         /** @var ResourceLoaderContext */
 157         private $rlClientContext;
 158
 159         /** @var array */
 160         private $rlExemptStyleModules;
 161
 162         /** @var array */
 163         protected $mJsConfigVars = [];
 164
 165         /** @var array */
 166         protected $mTemplateIds = [];
 167
 168         /** @var array */
 169         protected $mImageTimeKeys = [];
 170
 171         /** @var string */
 172         public $mRedirectCode = '';
 173
 174         protected $mFeedLinksAppendQuery = null;
 175
 176         /** @var array
 177          * What level of 'untrustworthiness' is allowed in CSS/JS modules loaded on this page?
 178          * @see ResourceLoaderModule::$origin
 179          * ResourceLoaderModule::ORIGIN_ALL is assumed unless overridden;
 180          */
 181         protected $mAllowedModules = [
 182                 ResourceLoaderModule::TYPE_COMBINED => ResourceLoaderModule::ORIGIN_ALL,
 183         ];
 184
 185         /** @var bool Whether output is disabled.  If this is true, the 'output' method will do nothing. */
 186         protected $mDoNothing = false;
 187
 188         // Parser related.
 189
 190         /** @var int */
 191         protected $mContainsNewMagic = 0;
 192
 193         /**
 194          * lazy initialised, use parserOptions()
 195          * @var ParserOptions
 196          */
 197         protected $mParserOptions = null;
 198
 199         /**
 200          * Handles the Atom / RSS links.
 201          * We probably only support Atom in 2011.
 202          * @see $wgAdvertisedFeedTypes
 203          */
 204         private $mFeedLinks = [];
 205
 206         // Gwicke work on squid caching? Roughly from 2003.
 207         protected $mEnableClientCache = true;
 208
 209         /** @var bool Flag if output should only contain the body of the article. */
 210         private $mArticleBodyOnly = false;
 211
 212         /** @var bool */
 213         protected $mNewSectionLink = false;
 214
 215         /** @var bool */
 216         protected $mHideNewSectionLink = false;
 217
 218         /**
 219          * @var bool Comes from the parser. This was probably made to load CSS/JS
 220          * only if we had "<gallery>". Used directly in CategoryPage.php.
 221          * Looks like ResourceLoader can replace this.
 222          */
 223         public $mNoGallery = false;
 224
 225         /** @var int Cache stuff. Looks like mEnableClientCache */
 226         protected $mCdnMaxage = 0;
 227         /** @var int Upper limit on mCdnMaxage */
 228         protected $mCdnMaxageLimit = INF;
 229
 230         /**
 231          * @var bool Controls if anti-clickjacking / frame-breaking headers will
 232          * be sent. This should be done for pages where edit actions are possible.
 233          * Setters: $this->preventClickjacking() and $this->allowClickjacking().
 234          */
 235         protected $mPreventClickjacking = true;
 236
 237         /** @var int To include the variable {{REVISIONID}} */
 238         private $mRevisionId = null;
 239
 240         /** @var string */
 241         private $mRevisionTimestamp = null;
 242
 243         /** @var array */
 244         protected $mFileVersion = null;
 245
 246         /**
 247          * @var array An array of stylesheet filenames (relative from skins path),
 248          * with options for CSS media, IE conditions, and RTL/LTR direction.
 249          * For internal use; add settings in the skin via $this->addStyle()
 250          *
 251          * Style again! This seems like a code duplication since we already have
 252          * mStyles. This is what makes Open Source amazing.
 253          */
 254         protected $styles = [];
 255
 256         private $mIndexPolicy = 'index';
 257         private $mFollowPolicy = 'follow';
 258
 259         /**
 260          * @var array Headers that cause the cache to vary.  Key is header name, value is an array of
 261          * options for the Key header.
 262          */
 263         private $mVaryHeader = [
 264                 'Accept-Encoding' => [ 'match=gzip' ],
 265         ];
 266
 267         /**
 268          * If the current page was reached through a redirect, $mRedirectedFrom contains the Title
 269          * of the redirect.
 270          *
 271          * @var Title
 272          */
 273         private $mRedirectedFrom = null;
 274
 275         /**
 276          * Additional key => value data
 277          */
 278         private $mProperties = [];
 279
 280         /**
 281          * @var string|null ResourceLoader target for load.php links. If null, will be omitted
 282          */
 283         private $mTarget = null;
 284
 285         /**
 286          * @var bool Whether parser output contains a table of contents
 287          */
 288         private $mEnableTOC = false;
 289
 290         /**
 291          * @var string|null The URL to send in a <link> element with rel=license
 292          */
 293         private $copyrightUrl;
 294
 295         /** @var array Profiling data */
 296         private $limitReportJSData = [];
 297
 298         /** @var array Map Title to Content */
 299         private $contentOverrides = [];
 300
 301         /** @var callable[] */
 302         private $contentOverrideCallbacks = [];
 303
 304         /**
 305          * Link: header contents
 306          */
 307         private $mLinkHeader = [];
 308
 309         /**
 310          * @var string The nonce for Content-Security-Policy
 311          */
 312         private $CSPNonce;
 313
 314         /**
 315          * Constructor for OutputPage. This should not be called directly.
 316          * Instead a new RequestContext should be created and it will implicitly create
 317          * a OutputPage tied to that context.
 318          * @param IContextSource $context
 319          */
 320         function __construct( IContextSource $context ) {
 321                 $this->setContext( $context );
 322         }
 323
 324         /**
 325          * Redirect to $url rather than displaying the normal page
 326          *
 327          * @param string $url
 328          * @param string $responsecode HTTP status code
 329          */
 330         public function redirect( $url, $responsecode = '302' ) {
 331                 # Strip newlines as a paranoia check for header injection in PHP<5.1.2
 332                 $this->mRedirect = str_replace( "\n", '', $url );
 333                 $this->mRedirectCode = $responsecode;
 334         }
 335
 336         /**
 337          * Get the URL to redirect to, or an empty string if not redirect URL set
 338          *
 339          * @return string
 340          */
 341         public function getRedirect() {
 342                 return $this->mRedirect;
 343         }
 344
 345         /**
 346          * Set the copyright URL to send with the output.
 347          * Empty string to omit, null to reset.
 348          *
 349          * @since 1.26
 350          *
 351          * @param string|null $url
 352          */
 353         public function setCopyrightUrl( $url ) {
 354                 $this->copyrightUrl = $url;
 355         }
 356
 357         /**
 358          * Set the HTTP status code to send with the output.
 359          *
 360          * @param int $statusCode
 361          */
 362         public function setStatusCode( $statusCode ) {
 363                 $this->mStatusCode = $statusCode;
 364         }
 365
 366         /**
 367          * Add a new "<meta>" tag
 368          * To add an http-equiv meta tag, precede the name with "http:"
 369          *
 370          * @param string $name Name of the meta tag
 371          * @param string $val Value of the meta tag
 372          */
 373         function addMeta( $name, $val ) {
 374                 array_push( $this->mMetatags, [ $name, $val ] );
 375         }
 376
 377         /**
 378          * Returns the current <meta> tags
 379          *
 380          * @since 1.25
 381          * @return array
 382          */
 383         public function getMetaTags() {
 384                 return $this->mMetatags;
 385         }
 386
 387         /**
 388          * Add a new \<link\> tag to the page header.
 389          *
 390          * Note: use setCanonicalUrl() for rel=canonical.
 391          *
 392          * @param array $linkarr Associative array of attributes.
 393          */
 394         function addLink( array $linkarr ) {
 395                 array_push( $this->mLinktags, $linkarr );
 396         }
 397
 398         /**
 399          * Returns the current <link> tags
 400          *
 401          * @since 1.25
 402          * @return array
 403          */
 404         public function getLinkTags() {
 405                 return $this->mLinktags;
 406         }
 407
 408         /**
 409          * Set the URL to be used for the <link rel=canonical>. This should be used
 410          * in preference to addLink(), to avoid duplicate link tags.
 411          * @param string $url
 412          */
 413         function setCanonicalUrl( $url ) {
 414                 $this->mCanonicalUrl = $url;
 415         }
 416
 417         /**
 418          * Returns the URL to be used for the <link rel=canonical> if
 419          * one is set.
 420          *
 421          * @since 1.25
 422          * @return bool|string
 423          */
 424         public function getCanonicalUrl() {
 425                 return $this->mCanonicalUrl;
 426         }
 427
 428         /**
 429          * Add raw HTML to the list of scripts (including \<script\> tag, etc.)
 430          * Internal use only. Use OutputPage::addModules() or OutputPage::addJsConfigVars()
 431          * if possible.
 432          *
 433          * @param string $script Raw HTML
 434          */
 435         function addScript( $script ) {
 436                 $this->mScripts .= $script;
 437         }
 438
 439         /**
 440          * Add a JavaScript file to be loaded as `<script>` on this page.
 441          *
 442          * Internal use only. Use OutputPage::addModules() if possible.
 443          *
 444          * @param string $file URL to file (absolute path, protocol-relative, or full url)
 445          * @param string|null $unused Previously used to change the cache-busting query parameter
 446          */
 447         public function addScriptFile( $file, $unused = null ) {
 448                 if ( substr( $file, 0, 1 ) !== '/' && !preg_match( '#^[a-z]*://#i', $file ) ) {
 449                         // This is not an absolute path, protocol-relative url, or full scheme url,
 450                         // presumed to be an old call intended to include a file from /w/skins/common,
 451                         // which doesn't exist anymore as of MediaWiki 1.24 per T71277. Ignore.
 452                         wfDeprecated( __METHOD__, '1.24' );
 453                         return;
 454                 }
 455                 $this->addScript( Html::linkedScript( $file, $this->getCSPNonce() ) );
 456         }
 457
 458         /**
 459          * Add a self-contained script tag with the given contents
 460          * Internal use only. Use OutputPage::addModules() if possible.
 461          *
 462          * @param string $script JavaScript text, no script tags
 463          */
 464         public function addInlineScript( $script ) {
 465                 $this->mScripts .= Html::inlineScript( "\n$script\n", $this->getCSPNonce() ) . "\n";
 466         }
 467
 468         /**
 469          * Filter an array of modules to remove insufficiently trustworthy members, and modules
 470          * which are no longer registered (eg a page is cached before an extension is disabled)
 471          * @param array $modules
 472          * @param string|null $position Unused
 473          * @param string $type
 474          * @return array
 475          */
 476         protected function filterModules( array $modules, $position = null,
 477                 $type = ResourceLoaderModule::TYPE_COMBINED
 478         ) {
 479                 $resourceLoader = $this->getResourceLoader();
 480                 $filteredModules = [];
 481                 foreach ( $modules as $val ) {
 482                         $module = $resourceLoader->getModule( $val );
 483                         if ( $module instanceof ResourceLoaderModule
 484                                 && $module->getOrigin() <= $this->getAllowedModules( $type )
 485                         ) {
 486                                 if ( $this->mTarget && !in_array( $this->mTarget, $module->getTargets() ) ) {
 487                                         $this->warnModuleTargetFilter( $module->getName() );
 488                                         continue;
 489                                 }
 490                                 $filteredModules[] = $val;
 491                         }
 492                 }
 493                 return $filteredModules;
 494         }
 495
 496         private function warnModuleTargetFilter( $moduleName ) {
 497                 static $warnings = [];
 498                 if ( isset( $warnings[$this->mTarget][$moduleName] ) ) {
 499                         return;
 500                 }
 501                 $warnings[$this->mTarget][$moduleName] = true;
 502                 $this->getResourceLoader()->getLogger()->debug(
 503                         'Module "{module}" not loadable on target "{target}".',
 504                         [
 505                                 'module' => $moduleName,
 506                                 'target' => $this->mTarget,
 507                         ]
 508                 );
 509         }
 510
 511         /**
 512          * Get the list of modules to include on this page
 513          *
 514          * @param bool $filter Whether to filter out insufficiently trustworthy modules
 515          * @param string|null $position Unused
 516          * @param string $param
 517          * @param string $type
 518          * @return array Array of module names
 519          */
 520         public function getModules( $filter = false, $position = null, $param = 'mModules',
 521                 $type = ResourceLoaderModule::TYPE_COMBINED
 522         ) {
 523                 $modules = array_values( array_unique( $this->$param ) );
 524                 return $filter
 525                         ? $this->filterModules( $modules, null, $type )
 526                         : $modules;
 527         }
 528
 529         /**
 530          * Load one or more ResourceLoader modules on this page.
 531          *
 532          * @param string|array $modules Module name (string) or array of module names
 533          */
 534         public function addModules( $modules ) {
 535                 $this->mModules = array_merge( $this->mModules, (array)$modules );
 536         }
 537
 538         /**
 539          * Get the list of script-only modules to load on this page.
 540          *
 541          * @param bool $filter
 542          * @param string|null $position Unused
 543          * @return array Array of module names
 544          */
 545         public function getModuleScripts( $filter = false, $position = null ) {
 546                 return $this->getModules( $filter, null, 'mModuleScripts',
 547                         ResourceLoaderModule::TYPE_SCRIPTS
 548                 );
 549         }
 550
 551         /**
 552          * Load the scripts of one or more ResourceLoader modules, on this page.
 553          *
 554          * This method exists purely to provide the legacy behaviour of loading
 555          * a module's scripts in the global scope, and without dependency resolution.
 556          * See <https://phabricator.wikimedia.org/T188689>.
 557          *
 558          * @deprecated since 1.31 Use addModules() instead.
 559          * @param string|array $modules Module name (string) or array of module names
 560          */
 561         public function addModuleScripts( $modules ) {
 562                 $this->mModuleScripts = array_merge( $this->mModuleScripts, (array)$modules );
 563         }
 564
 565         /**
 566          * Get the list of style-only modules to load on this page.
 567          *
 568          * @param bool $filter
 569          * @param string|null $position Unused
 570          * @return array Array of module names
 571          */
 572         public function getModuleStyles( $filter = false, $position = null ) {
 573                 return $this->getModules( $filter, null, 'mModuleStyles',
 574                         ResourceLoaderModule::TYPE_STYLES
 575                 );
 576         }
 577
 578         /**
 579          * Load the styles of one or more ResourceLoader modules on this page.
 580          *
 581          * Module styles added through this function will be loaded as a stylesheet,
 582          * using a standard `<link rel=stylesheet>` HTML tag, rather than as a combined
 583          * Javascript and CSS package. Thus, they will even load when JavaScript is disabled.
 584          *
 585          * @param string|array $modules Module name (string) or array of module names
 586          */
 587         public function addModuleStyles( $modules ) {
 588                 $this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
 589         }
 590
 591         /**
 592          * @return null|string ResourceLoader target
 593          */
 594         public function getTarget() {
 595                 return $this->mTarget;
 596         }
 597
 598         /**
 599          * Sets ResourceLoader target for load.php links. If null, will be omitted
 600          *
 601          * @param string|null $target
 602          */
 603         public function setTarget( $target ) {
 604                 $this->mTarget = $target;
 605         }
 606
 607         /**
 608          * Add a mapping from a LinkTarget to a Content, for things like page preview.
 609          * @see self::addContentOverrideCallback()
 610          * @since 1.32
 611          * @param LinkTarget $target
 612          * @param Content $content
 613          */
 614         public function addContentOverride( LinkTarget $target, Content $content ) {
 615                 if ( !$this->contentOverrides ) {
 616                         // Register a callback for $this->contentOverrides on the first call
 617                         $this->addContentOverrideCallback( function ( LinkTarget $target ) {
 618                                 $key = $target->getNamespace() . ':' . $target->getDBkey();
 619                                 return $this->contentOverrides[$key] ?? null;
 620                         } );
 621                 }
 622
 623                 $key = $target->getNamespace() . ':' . $target->getDBkey();
 624                 $this->contentOverrides[$key] = $content;
 625         }
 626
 627         /**
 628          * Add a callback for mapping from a Title to a Content object, for things
 629          * like page preview.
 630          * @see ResourceLoaderContext::getContentOverrideCallback()
 631          * @since 1.32
 632          * @param callable $callback
 633          */
 634         public function addContentOverrideCallback( callable $callback ) {
 635                 $this->contentOverrideCallbacks[] = $callback;
 636         }
 637
 638         /**
 639          * Get an array of head items
 640          *
 641          * @return array
 642          */
 643         function getHeadItemsArray() {
 644                 return $this->mHeadItems;
 645         }
 646
 647         /**
 648          * Add or replace a head item to the output
 649          *
 650          * Whenever possible, use more specific options like ResourceLoader modules,
 651          * OutputPage::addLink(), OutputPage::addMetaLink() and OutputPage::addFeedLink()
 652          * Fallback options for those are: OutputPage::addStyle, OutputPage::addScript(),
 653          * OutputPage::addInlineScript() and OutputPage::addInlineStyle()
 654          * This would be your very LAST fallback.
 655          *
 656          * @param string $name Item name
 657          * @param string $value Raw HTML
 658          */
 659         public function addHeadItem( $name, $value ) {
 660                 $this->mHeadItems[$name] = $value;
 661         }
 662
 663         /**
 664          * Add one or more head items to the output
 665          *
 666          * @since 1.28
 667          * @param string|string[] $values Raw HTML
 668          */
 669         public function addHeadItems( $values ) {
 670                 $this->mHeadItems = array_merge( $this->mHeadItems, (array)$values );
 671         }
 672
 673         /**
 674          * Check if the header item $name is already set
 675          *
 676          * @param string $name Item name
 677          * @return bool
 678          */
 679         public function hasHeadItem( $name ) {
 680                 return isset( $this->mHeadItems[$name] );
 681         }
 682
 683         /**
 684          * Add a class to the <body> element
 685          *
 686          * @since 1.30
 687          * @param string|string[] $classes One or more classes to add
 688          */
 689         public function addBodyClasses( $classes ) {
 690                 $this->mAdditionalBodyClasses = array_merge( $this->mAdditionalBodyClasses, (array)$classes );
 691         }
 692
 693         /**
 694          * Set whether the output should only contain the body of the article,
 695          * without any skin, sidebar, etc.
 696          * Used e.g. when calling with "action=render".
 697          *
 698          * @param bool $only Whether to output only the body of the article
 699          */
 700         public function setArticleBodyOnly( $only ) {
 701                 $this->mArticleBodyOnly = $only;
 702         }
 703
 704         /**
 705          * Return whether the output will contain only the body of the article
 706          *
 707          * @return bool
 708          */
 709         public function getArticleBodyOnly() {
 710                 return $this->mArticleBodyOnly;
 711         }
 712
 713         /**
 714          * Set an additional output property
 715          * @since 1.21
 716          *
 717          * @param string $name
 718          * @param mixed $value
 719          */
 720         public function setProperty( $name, $value ) {
 721                 $this->mProperties[$name] = $value;
 722         }
 723
 724         /**
 725          * Get an additional output property
 726          * @since 1.21
 727          *
 728          * @param string $name
 729          * @return mixed Property value or null if not found
 730          */
 731         public function getProperty( $name ) {
 732                 return $this->mProperties[$name] ?? null;
 733         }
 734
 735         /**
 736          * checkLastModified tells the client to use the client-cached page if
 737          * possible. If successful, the OutputPage is disabled so that
 738          * any future call to OutputPage->output() have no effect.
 739          *
 740          * Side effect: sets mLastModified for Last-Modified header
 741          *
 742          * @param string $timestamp
 743          *
 744          * @return bool True if cache-ok headers was sent.
 745          */
 746         public function checkLastModified( $timestamp ) {
 747                 if ( !$timestamp || $timestamp == '19700101000000' ) {
 748                         wfDebug( __METHOD__ . ": CACHE DISABLED, NO TIMESTAMP\n" );
 749                         return false;
 750                 }
 751                 $config = $this->getConfig();
 752                 if ( !$config->get( 'CachePages' ) ) {
 753                         wfDebug( __METHOD__ . ": CACHE DISABLED\n" );
 754                         return false;
 755                 }
 756
 757                 $timestamp = wfTimestamp( TS_MW, $timestamp );
 758                 $modifiedTimes = [
 759                         'page' => $timestamp,
 760                         'user' => $this->getUser()->getTouched(),
 761                         'epoch' => $config->get( 'CacheEpoch' )
 762                 ];
 763                 if ( $config->get( 'UseSquid' ) ) {
 764                         $modifiedTimes['sepoch'] = wfTimestamp( TS_MW, $this->getCdnCacheEpoch(
 765                                 time(),
 766                                 $config->get( 'SquidMaxage' )
 767                         ) );
 768                 }
 769                 Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this ] );
 770
 771                 $maxModified = max( $modifiedTimes );
 772                 $this->mLastModified = wfTimestamp( TS_RFC2822, $maxModified );
 773
 774                 $clientHeader = $this->getRequest()->getHeader( 'If-Modified-Since' );
 775                 if ( $clientHeader === false ) {
 776                         wfDebug( __METHOD__ . ": client did not send If-Modified-Since header", 'private' );
 777                         return false;
 778                 }
 779
 780                 # IE sends sizes after the date like this:
 781                 # Wed, 20 Aug 2003 06:51:19 GMT; length=5202
 782                 # this breaks strtotime().
 783                 $clientHeader = preg_replace( '/;.*$/', '', $clientHeader );
 784
 785                 Wikimedia\suppressWarnings(); // E_STRICT system time warnings
 786                 $clientHeaderTime = strtotime( $clientHeader );
 787                 Wikimedia\restoreWarnings();
 788                 if ( !$clientHeaderTime ) {
 789                         wfDebug( __METHOD__
 790                                 . ": unable to parse the client's If-Modified-Since header: $clientHeader\n" );
 791                         return false;
 792                 }
 793                 $clientHeaderTime = wfTimestamp( TS_MW, $clientHeaderTime );
 794
 795                 # Make debug info
 796                 $info = '';
 797                 foreach ( $modifiedTimes as $name => $value ) {
 798                         if ( $info !== '' ) {
 799                                 $info .= ', ';
 800                         }
 801                         $info .= "$name=" . wfTimestamp( TS_ISO_8601, $value );
 802                 }
 803
 804                 wfDebug( __METHOD__ . ": client sent If-Modified-Since: " .
 805                         wfTimestamp( TS_ISO_8601, $clientHeaderTime ), 'private' );
 806                 wfDebug( __METHOD__ . ": effective Last-Modified: " .
 807                         wfTimestamp( TS_ISO_8601, $maxModified ), 'private' );
 808                 if ( $clientHeaderTime < $maxModified ) {
 809                         wfDebug( __METHOD__ . ": STALE, $info", 'private' );
 810                         return false;
 811                 }
 812
 813                 # Not modified
 814                 # Give a 304 Not Modified response code and disable body output
 815                 wfDebug( __METHOD__ . ": NOT MODIFIED, $info", 'private' );
 816                 ini_set( 'zlib.output_compression', 0 );
 817                 $this->getRequest()->response()->statusHeader( 304 );
 818                 $this->sendCacheControl();
 819                 $this->disable();
 820
 821                 // Don't output a compressed blob when using ob_gzhandler;
 822                 // it's technically against HTTP spec and seems to confuse
 823                 // Firefox when the response gets split over two packets.
 824                 wfClearOutputBuffers();
 825
 826                 return true;
 827         }
 828
 829         /**
 830          * @param int $reqTime Time of request (eg. now)
 831          * @param int $maxAge Cache TTL in seconds
 832          * @return int Timestamp
 833          */
 834         private function getCdnCacheEpoch( $reqTime, $maxAge ) {
 835                 // Ensure Last-Modified is never more than (wgSquidMaxage) in the past,
 836                 // because even if the wiki page content hasn't changed since, static
 837                 // resources may have changed (skin HTML, interface messages, urls, etc.)
 838                 // and must roll-over in a timely manner (T46570)
 839                 return $reqTime - $maxAge;
 840         }
 841
 842         /**
 843          * Override the last modified timestamp
 844          *
 845          * @param string $timestamp New timestamp, in a format readable by
 846          *        wfTimestamp()
 847          */
 848         public function setLastModified( $timestamp ) {
 849                 $this->mLastModified = wfTimestamp( TS_RFC2822, $timestamp );
 850         }
 851
 852         /**
 853          * Set the robot policy for the page: <http://www.robotstxt.org/meta.html>
 854          *
 855          * @param string $policy The literal string to output as the contents of
 856          *   the meta tag.  Will be parsed according to the spec and output in
 857          *   standardized form.
 858          * @return null
 859          */
 860         public function setRobotPolicy( $policy ) {
 861                 $policy = Article::formatRobotPolicy( $policy );
 862
 863                 if ( isset( $policy['index'] ) ) {
 864                         $this->setIndexPolicy( $policy['index'] );
 865                 }
 866                 if ( isset( $policy['follow'] ) ) {
 867                         $this->setFollowPolicy( $policy['follow'] );
 868                 }
 869         }
 870
 871         /**
 872          * Set the index policy for the page, but leave the follow policy un-
 873          * touched.
 874          *
 875          * @param string $policy Either 'index' or 'noindex'.
 876          * @return null
 877          */
 878         public function setIndexPolicy( $policy ) {
 879                 $policy = trim( $policy );
 880                 if ( in_array( $policy, [ 'index', 'noindex' ] ) ) {
 881                         $this->mIndexPolicy = $policy;
 882                 }
 883         }
 884
 885         /**
 886          * Set the follow policy for the page, but leave the index policy un-
 887          * touched.
 888          *
 889          * @param string $policy Either 'follow' or 'nofollow'.
 890          * @return null
 891          */
 892         public function setFollowPolicy( $policy ) {
 893                 $policy = trim( $policy );
 894                 if ( in_array( $policy, [ 'follow', 'nofollow' ] ) ) {
 895                         $this->mFollowPolicy = $policy;
 896                 }
 897         }
 898
 899         /**
 900          * "HTML title" means the contents of "<title>".
 901          * It is stored as plain, unescaped text and will be run through htmlspecialchars in the skin file.
 902          *
 903          * @param string|Message $name
 904          */
 905         public function setHTMLTitle( $name ) {
 906                 if ( $name instanceof Message ) {
 907                         $this->mHTMLtitle = $name->setContext( $this->getContext() )->text();
 908                 } else {
 909                         $this->mHTMLtitle = $name;
 910                 }
 911         }
 912
 913         /**
 914          * Return the "HTML title", i.e. the content of the "<title>" tag.
 915          *
 916          * @return string
 917          */
 918         public function getHTMLTitle() {
 919                 return $this->mHTMLtitle;
 920         }
 921
 922         /**
 923          * Set $mRedirectedFrom, the Title of the page which redirected us to the current page.
 924          *
 925          * @param Title $t
 926          */
 927         public function setRedirectedFrom( $t ) {
 928                 $this->mRedirectedFrom = $t;
 929         }
 930
 931         /**
 932          * "Page title" means the contents of \<h1\>. It is stored as a valid HTML
 933          * fragment. This function allows good tags like \<sup\> in the \<h1\> tag,
 934          * but not bad tags like \<script\>. This function automatically sets
 935          * \<title\> to the same content as \<h1\> but with all tags removed. Bad
 936          * tags that were escaped in \<h1\> will still be escaped in \<title\>, and
 937          * good tags like \<i\> will be dropped entirely.
 938          *
 939          * @param string|Message $name
 940          */
 941         public function setPageTitle( $name ) {
 942                 if ( $name instanceof Message ) {
 943                         $name = $name->setContext( $this->getContext() )->text();
 944                 }
 945
 946                 # change "<script>foo&bar</script>" to "&lt;script&gt;foo&amp;bar&lt;/script&gt;"
 947                 # but leave "<i>foobar</i>" alone
 948                 $nameWithTags = Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $name ) );
 949                 $this->mPageTitle = $nameWithTags;
 950
 951                 # change "<i>foo&amp;bar</i>" to "foo&bar"
 952                 $this->setHTMLTitle(
 953                         $this->msg( 'pagetitle' )->rawParams( Sanitizer::stripAllTags( $nameWithTags ) )
 954                                 ->inContentLanguage()
 955                 );
 956         }
 957
 958         /**
 959          * Return the "page title", i.e. the content of the \<h1\> tag.
 960          *
 961          * @return string
 962          */
 963         public function getPageTitle() {
 964                 return $this->mPageTitle;
 965         }
 966
 967         /**
 968          * Set the Title object to use
 969          *
 970          * @param Title $t
 971          */
 972         public function setTitle( Title $t ) {
 973                 $this->getContext()->setTitle( $t );
 974         }
 975
 976         /**
 977          * Replace the subtitle with $str
 978          *
 979          * @param string|Message $str New value of the subtitle. String should be safe HTML.
 980          */
 981         public function setSubtitle( $str ) {
 982                 $this->clearSubtitle();
 983                 $this->addSubtitle( $str );
 984         }
 985
 986         /**
 987          * Add $str to the subtitle
 988          *
 989          * @param string|Message $str String or Message to add to the subtitle. String should be safe HTML.
 990          */
 991         public function addSubtitle( $str ) {
 992                 if ( $str instanceof Message ) {
 993                         $this->mSubtitle[] = $str->setContext( $this->getContext() )->parse();
 994                 } else {
 995                         $this->mSubtitle[] = $str;
 996                 }
 997         }
 998
 999         /**
1000          * Build message object for a subtitle containing a backlink to a page
1001          *
1002          * @param Title $title Title to link to
1003          * @param array $query Array of additional parameters to include in the link
1004          * @return Message
1005          * @since 1.25
1006          */
1007         public static function buildBacklinkSubtitle( Title $title, $query = [] ) {
1008                 if ( $title->isRedirect() ) {
1009                         $query['redirect'] = 'no';
1010                 }
1011                 $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1012                 return wfMessage( 'backlinksubtitle' )
1013                         ->rawParams( $linkRenderer->makeLink( $title, null, [], $query ) );
1014         }
1015
1016         /**
1017          * Add a subtitle containing a backlink to a page
1018          *
1019          * @param Title $title Title to link to
1020          * @param array $query Array of additional parameters to include in the link
1021          */
1022         public function addBacklinkSubtitle( Title $title, $query = [] ) {
1023                 $this->addSubtitle( self::buildBacklinkSubtitle( $title, $query ) );
1024         }
1025
1026         /**
1027          * Clear the subtitles
1028          */
1029         public function clearSubtitle() {
1030                 $this->mSubtitle = [];
1031         }
1032
1033         /**
1034          * Get the subtitle
1035          *
1036          * @return string
1037          */
1038         public function getSubtitle() {
1039                 return implode( "<br />\n\t\t\t\t", $this->mSubtitle );
1040         }
1041
1042         /**
1043          * Set the page as printable, i.e. it'll be displayed with all
1044          * print styles included
1045          */
1046         public function setPrintable() {
1047                 $this->mPrintable = true;
1048         }
1049
1050         /**
1051          * Return whether the page is "printable"
1052          *
1053          * @return bool
1054          */
1055         public function isPrintable() {
1056                 return $this->mPrintable;
1057         }
1058
1059         /**
1060          * Disable output completely, i.e. calling output() will have no effect
1061          */
1062         public function disable() {
1063                 $this->mDoNothing = true;
1064         }
1065
1066         /**
1067          * Return whether the output will be completely disabled
1068          *
1069          * @return bool
1070          */
1071         public function isDisabled() {
1072                 return $this->mDoNothing;
1073         }
1074
1075         /**
1076          * Show an "add new section" link?
1077          *
1078          * @return bool
1079          */
1080         public function showNewSectionLink() {
1081                 return $this->mNewSectionLink;
1082         }
1083
1084         /**
1085          * Forcibly hide the new section link?
1086          *
1087          * @return bool
1088          */
1089         public function forceHideNewSectionLink() {
1090                 return $this->mHideNewSectionLink;
1091         }
1092
1093         /**
1094          * Add or remove feed links in the page header
1095          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1096          * for the new version
1097          * @see addFeedLink()
1098          *
1099          * @param bool $show True: add default feeds, false: remove all feeds
1100          */
1101         public function setSyndicated( $show = true ) {
1102                 if ( $show ) {
1103                         $this->setFeedAppendQuery( false );
1104                 } else {
1105                         $this->mFeedLinks = [];
1106                 }
1107         }
1108
1109         /**
1110          * Add default feeds to the page header
1111          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1112          * for the new version
1113          * @see addFeedLink()
1114          *
1115          * @param string $val Query to append to feed links or false to output
1116          *        default links
1117          */
1118         public function setFeedAppendQuery( $val ) {
1119                 $this->mFeedLinks = [];
1120
1121                 foreach ( $this->getConfig()->get( 'AdvertisedFeedTypes' ) as $type ) {
1122                         $query = "feed=$type";
1123                         if ( is_string( $val ) ) {
1124                                 $query .= '&' . $val;
1125                         }
1126                         $this->mFeedLinks[$type] = $this->getTitle()->getLocalURL( $query );
1127                 }
1128         }
1129
1130         /**
1131          * Add a feed link to the page header
1132          *
1133          * @param string $format Feed type, should be a key of $wgFeedClasses
1134          * @param string $href URL
1135          */
1136         public function addFeedLink( $format, $href ) {
1137                 if ( in_array( $format, $this->getConfig()->get( 'AdvertisedFeedTypes' ) ) ) {
1138                         $this->mFeedLinks[$format] = $href;
1139                 }
1140         }
1141
1142         /**
1143          * Should we output feed links for this page?
1144          * @return bool
1145          */
1146         public function isSyndicated() {
1147                 return count( $this->mFeedLinks ) > 0;
1148         }
1149
1150         /**
1151          * Return URLs for each supported syndication format for this page.
1152          * @return array Associating format keys with URLs
1153          */
1154         public function getSyndicationLinks() {
1155                 return $this->mFeedLinks;
1156         }
1157
1158         /**
1159          * Will currently always return null
1160          *
1161          * @return null
1162          */
1163         public function getFeedAppendQuery() {
1164                 return $this->mFeedLinksAppendQuery;
1165         }
1166
1167         /**
1168          * Set whether the displayed content is related to the source of the
1169          * corresponding article on the wiki
1170          * Setting true will cause the change "article related" toggle to true
1171          *
1172          * @param bool $newVal
1173          */
1174         public function setArticleFlag( $newVal ) {
1175                 $this->mIsArticle = $newVal;
1176                 if ( $newVal ) {
1177                         $this->mIsArticleRelated = $newVal;
1178                 }
1179         }
1180
1181         /**
1182          * Return whether the content displayed page is related to the source of
1183          * the corresponding article on the wiki
1184          *
1185          * @return bool
1186          */
1187         public function isArticle() {
1188                 return $this->mIsArticle;
1189         }
1190
1191         /**
1192          * Set whether this page is related an article on the wiki
1193          * Setting false will cause the change of "article flag" toggle to false
1194          *
1195          * @param bool $newVal
1196          */
1197         public function setArticleRelated( $newVal ) {
1198                 $this->mIsArticleRelated = $newVal;
1199                 if ( !$newVal ) {
1200                         $this->mIsArticle = false;
1201                 }
1202         }
1203
1204         /**
1205          * Return whether this page is related an article on the wiki
1206          *
1207          * @return bool
1208          */
1209         public function isArticleRelated() {
1210                 return $this->mIsArticleRelated;
1211         }
1212
1213         /**
1214          * Add new language links
1215          *
1216          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1217          *                               (e.g. 'fr:Test page')
1218          */
1219         public function addLanguageLinks( array $newLinkArray ) {
1220                 $this->mLanguageLinks = array_merge( $this->mLanguageLinks, $newLinkArray );
1221         }
1222
1223         /**
1224          * Reset the language links and add new language links
1225          *
1226          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1227          *                               (e.g. 'fr:Test page')
1228          */
1229         public function setLanguageLinks( array $newLinkArray ) {
1230                 $this->mLanguageLinks = $newLinkArray;
1231         }
1232
1233         /**
1234          * Get the list of language links
1235          *
1236          * @return string[] Array of interwiki-prefixed (non DB key) titles (e.g. 'fr:Test page')
1237          */
1238         public function getLanguageLinks() {
1239                 return $this->mLanguageLinks;
1240         }
1241
1242         /**
1243          * Add an array of categories, with names in the keys
1244          *
1245          * @param array $categories Mapping category name => sort key
1246          */
1247         public function addCategoryLinks( array $categories ) {
1248                 global $wgContLang;
1249
1250                 if ( !$categories ) {
1251                         return;
1252                 }
1253
1254                 $res = $this->addCategoryLinksToLBAndGetResult( $categories );
1255
1256                 # Set all the values to 'normal'.
1257                 $categories = array_fill_keys( array_keys( $categories ), 'normal' );
1258
1259                 # Mark hidden categories
1260                 foreach ( $res as $row ) {
1261                         if ( isset( $row->pp_value ) ) {
1262                                 $categories[$row->page_title] = 'hidden';
1263                         }
1264                 }
1265
1266                 // Avoid PHP 7.1 warning of passing $this by reference
1267                 $outputPage = $this;
1268                 # Add the remaining categories to the skin
1269                 if ( Hooks::run(
1270                         'OutputPageMakeCategoryLinks',
1271                         [ &$outputPage, $categories, &$this->mCategoryLinks ] )
1272                 ) {
1273                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1274                         foreach ( $categories as $category => $type ) {
1275                                 // array keys will cast numeric category names to ints, so cast back to string
1276                                 $category = (string)$category;
1277                                 $origcategory = $category;
1278                                 $title = Title::makeTitleSafe( NS_CATEGORY, $category );
1279                                 if ( !$title ) {
1280                                         continue;
1281                                 }
1282                                 $wgContLang->findVariantLink( $category, $title, true );
1283                                 if ( $category != $origcategory && array_key_exists( $category, $categories ) ) {
1284                                         continue;
1285                                 }
1286                                 $text = $wgContLang->convertHtml( $title->getText() );
1287                                 $this->mCategories[$type][] = $title->getText();
1288                                 $this->mCategoryLinks[$type][] = $linkRenderer->makeLink( $title, new HtmlArmor( $text ) );
1289                         }
1290                 }
1291         }
1292
1293         /**
1294          * @param array $categories
1295          * @return bool|IResultWrapper
1296          */
1297         protected function addCategoryLinksToLBAndGetResult( array $categories ) {
1298                 # Add the links to a LinkBatch
1299                 $arr = [ NS_CATEGORY => $categories ];
1300                 $lb = new LinkBatch;
1301                 $lb->setArray( $arr );
1302
1303                 # Fetch existence plus the hiddencat property
1304                 $dbr = wfGetDB( DB_REPLICA );
1305                 $fields = array_merge(
1306                         LinkCache::getSelectFields(),
1307                         [ 'page_namespace', 'page_title', 'pp_value' ]
1308                 );
1309
1310                 $res = $dbr->select( [ 'page', 'page_props' ],
1311                         $fields,
1312                         $lb->constructSet( 'page', $dbr ),
1313                         __METHOD__,
1314                         [],
1315                         [ 'page_props' => [ 'LEFT JOIN', [
1316                                 'pp_propname' => 'hiddencat',
1317                                 'pp_page = page_id'
1318                         ] ] ]
1319                 );
1320
1321                 # Add the results to the link cache
1322                 $linkCache = MediaWikiServices::getInstance()->getLinkCache();
1323                 $lb->addResultToCache( $linkCache, $res );
1324
1325                 return $res;
1326         }
1327
1328         /**
1329          * Reset the category links (but not the category list) and add $categories
1330          *
1331          * @param array $categories Mapping category name => sort key
1332          */
1333         public function setCategoryLinks( array $categories ) {
1334                 $this->mCategoryLinks = [];
1335                 $this->addCategoryLinks( $categories );
1336         }
1337
1338         /**
1339          * Get the list of category links, in a 2-D array with the following format:
1340          * $arr[$type][] = $link, where $type is either "normal" or "hidden" (for
1341          * hidden categories) and $link a HTML fragment with a link to the category
1342          * page
1343          *
1344          * @return array
1345          */
1346         public function getCategoryLinks() {
1347                 return $this->mCategoryLinks;
1348         }
1349
1350         /**
1351          * Get the list of category names this page belongs to.
1352          *
1353          * @param string $type The type of categories which should be returned. Possible values:
1354          *  * all: all categories of all types
1355          *  * hidden: only the hidden categories
1356          *  * normal: all categories, except hidden categories
1357          * @return array Array of strings
1358          */
1359         public function getCategories( $type = 'all' ) {
1360                 if ( $type === 'all' ) {
1361                         $allCategories = [];
1362                         foreach ( $this->mCategories as $categories ) {
1363                                 $allCategories = array_merge( $allCategories, $categories );
1364                         }
1365                         return $allCategories;
1366                 }
1367                 if ( !isset( $this->mCategories[$type] ) ) {
1368                         throw new InvalidArgumentException( 'Invalid category type given: ' . $type );
1369                 }
1370                 return $this->mCategories[$type];
1371         }
1372
1373         /**
1374          * Add an array of indicators, with their identifiers as array
1375          * keys and HTML contents as values.
1376          *
1377          * In case of duplicate keys, existing values are overwritten.
1378          *
1379          * @param array $indicators
1380          * @since 1.25
1381          */
1382         public function setIndicators( array $indicators ) {
1383                 $this->mIndicators = $indicators + $this->mIndicators;
1384                 // Keep ordered by key
1385                 ksort( $this->mIndicators );
1386         }
1387
1388         /**
1389          * Get the indicators associated with this page.
1390          *
1391          * The array will be internally ordered by item keys.
1392          *
1393          * @return array Keys: identifiers, values: HTML contents
1394          * @since 1.25
1395          */
1396         public function getIndicators() {
1397                 return $this->mIndicators;
1398         }
1399
1400         /**
1401          * Adds help link with an icon via page indicators.
1402          * Link target can be overridden by a local message containing a wikilink:
1403          * the message key is: lowercase action or special page name + '-helppage'.
1404          * @param string $to Target MediaWiki.org page title or encoded URL.
1405          * @param bool $overrideBaseUrl Whether $url is a full URL, to avoid MW.o.
1406          * @since 1.25
1407          */
1408         public function addHelpLink( $to, $overrideBaseUrl = false ) {
1409                 $this->addModuleStyles( 'mediawiki.helplink' );
1410                 $text = $this->msg( 'helppage-top-gethelp' )->escaped();
1411
1412                 if ( $overrideBaseUrl ) {
1413                         $helpUrl = $to;
1414                 } else {
1415                         $toUrlencoded = wfUrlencode( str_replace( ' ', '_', $to ) );
1416                         $helpUrl = "//www.mediawiki.org/wiki/Special:MyLanguage/$toUrlencoded";
1417                 }
1418
1419                 $link = Html::rawElement(
1420                         'a',
1421                         [
1422                                 'href' => $helpUrl,
1423                                 'target' => '_blank',
1424                                 'class' => 'mw-helplink',
1425                         ],
1426                         $text
1427                 );
1428
1429                 $this->setIndicators( [ 'mw-helplink' => $link ] );
1430         }
1431
1432         /**
1433          * Do not allow scripts which can be modified by wiki users to load on this page;
1434          * only allow scripts bundled with, or generated by, the software.
1435          * Site-wide styles are controlled by a config setting, since they can be
1436          * used to create a custom skin/theme, but not user-specific ones.
1437          *
1438          * @todo this should be given a more accurate name
1439          */
1440         public function disallowUserJs() {
1441                 $this->reduceAllowedModules(
1442                         ResourceLoaderModule::TYPE_SCRIPTS,
1443                         ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
1444                 );
1445
1446                 // Site-wide styles are controlled by a config setting, see T73621
1447                 // for background on why. User styles are never allowed.
1448                 if ( $this->getConfig()->get( 'AllowSiteCSSOnRestrictedPages' ) ) {
1449                         $styleOrigin = ResourceLoaderModule::ORIGIN_USER_SITEWIDE;
1450                 } else {
1451                         $styleOrigin = ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL;
1452                 }
1453                 $this->reduceAllowedModules(
1454                         ResourceLoaderModule::TYPE_STYLES,
1455                         $styleOrigin
1456                 );
1457         }
1458
1459         /**
1460          * Show what level of JavaScript / CSS untrustworthiness is allowed on this page
1461          * @see ResourceLoaderModule::$origin
1462          * @param string $type ResourceLoaderModule TYPE_ constant
1463          * @return int ResourceLoaderModule ORIGIN_ class constant
1464          */
1465         public function getAllowedModules( $type ) {
1466                 if ( $type == ResourceLoaderModule::TYPE_COMBINED ) {
1467                         return min( array_values( $this->mAllowedModules ) );
1468                 } else {
1469                         return $this->mAllowedModules[$type] ?? ResourceLoaderModule::ORIGIN_ALL;
1470                 }
1471         }
1472
1473         /**
1474          * Limit the highest level of CSS/JS untrustworthiness allowed.
1475          *
1476          * If passed the same or a higher level than the current level of untrustworthiness set, the
1477          * level will remain unchanged.
1478          *
1479          * @param string $type
1480          * @param int $level ResourceLoaderModule class constant
1481          */
1482         public function reduceAllowedModules( $type, $level ) {
1483                 $this->mAllowedModules[$type] = min( $this->getAllowedModules( $type ), $level );
1484         }
1485
1486         /**
1487          * Prepend $text to the body HTML
1488          *
1489          * @param string $text HTML
1490          */
1491         public function prependHTML( $text ) {
1492                 $this->mBodytext = $text . $this->mBodytext;
1493         }
1494
1495         /**
1496          * Append $text to the body HTML
1497          *
1498          * @param string $text HTML
1499          */
1500         public function addHTML( $text ) {
1501                 $this->mBodytext .= $text;
1502         }
1503
1504         /**
1505          * Shortcut for adding an Html::element via addHTML.
1506          *
1507          * @since 1.19
1508          *
1509          * @param string $element
1510          * @param array $attribs
1511          * @param string $contents
1512          */
1513         public function addElement( $element, array $attribs = [], $contents = '' ) {
1514                 $this->addHTML( Html::element( $element, $attribs, $contents ) );
1515         }
1516
1517         /**
1518          * Clear the body HTML
1519          */
1520         public function clearHTML() {
1521                 $this->mBodytext = '';
1522         }
1523
1524         /**
1525          * Get the body HTML
1526          *
1527          * @return string HTML
1528          */
1529         public function getHTML() {
1530                 return $this->mBodytext;
1531         }
1532
1533         /**
1534          * Get/set the ParserOptions object to use for wikitext parsing
1535          *
1536          * @param ParserOptions|null $options Either the ParserOption to use or null to only get the
1537          *   current ParserOption object. This parameter is deprecated since 1.31.
1538          * @return ParserOptions
1539          */
1540         public function parserOptions( $options = null ) {
1541                 if ( $options !== null ) {
1542                         wfDeprecated( __METHOD__ . ' with non-null $options', '1.31' );
1543                 }
1544
1545                 if ( $options !== null && !empty( $options->isBogus ) ) {
1546                         // Someone is trying to set a bogus pre-$wgUser PO. Check if it has
1547                         // been changed somehow, and keep it if so.
1548                         $anonPO = ParserOptions::newFromAnon();
1549                         $anonPO->setAllowUnsafeRawHtml( false );
1550                         if ( !$options->matches( $anonPO ) ) {
1551                                 wfLogWarning( __METHOD__ . ': Setting a changed bogus ParserOptions: ' . wfGetAllCallers( 5 ) );
1552                                 $options->isBogus = false;
1553                         }
1554                 }
1555
1556                 if ( !$this->mParserOptions ) {
1557                         if ( !$this->getContext()->getUser()->isSafeToLoad() ) {
1558                                 // $wgUser isn't unstubbable yet, so don't try to get a
1559                                 // ParserOptions for it. And don't cache this ParserOptions
1560                                 // either.
1561                                 $po = ParserOptions::newFromAnon();
1562                                 $po->setAllowUnsafeRawHtml( false );
1563                                 $po->isBogus = true;
1564                                 if ( $options !== null ) {
1565                                         $this->mParserOptions = empty( $options->isBogus ) ? $options : null;
1566                                 }
1567                                 return $po;
1568                         }
1569
1570                         $this->mParserOptions = ParserOptions::newFromContext( $this->getContext() );
1571                         $this->mParserOptions->setAllowUnsafeRawHtml( false );
1572                 }
1573
1574                 if ( $options !== null && !empty( $options->isBogus ) ) {
1575                         // They're trying to restore the bogus pre-$wgUser PO. Do the right
1576                         // thing.
1577                         return wfSetVar( $this->mParserOptions, null, true );
1578                 } else {
1579                         return wfSetVar( $this->mParserOptions, $options );
1580                 }
1581         }
1582
1583         /**
1584          * Set the revision ID which will be seen by the wiki text parser
1585          * for things such as embedded {{REVISIONID}} variable use.
1586          *
1587          * @param int|null $revid A positive integer, or null
1588          * @return mixed Previous value
1589          */
1590         public function setRevisionId( $revid ) {
1591                 $val = is_null( $revid ) ? null : intval( $revid );
1592                 return wfSetVar( $this->mRevisionId, $val, true );
1593         }
1594
1595         /**
1596          * Get the displayed revision ID
1597          *
1598          * @return int
1599          */
1600         public function getRevisionId() {
1601                 return $this->mRevisionId;
1602         }
1603
1604         /**
1605          * Set the timestamp of the revision which will be displayed. This is used
1606          * to avoid a extra DB call in Skin::lastModified().
1607          *
1608          * @param string|null $timestamp
1609          * @return mixed Previous value
1610          */
1611         public function setRevisionTimestamp( $timestamp ) {
1612                 return wfSetVar( $this->mRevisionTimestamp, $timestamp, true );
1613         }
1614
1615         /**
1616          * Get the timestamp of displayed revision.
1617          * This will be null if not filled by setRevisionTimestamp().
1618          *
1619          * @return string|null
1620          */
1621         public function getRevisionTimestamp() {
1622                 return $this->mRevisionTimestamp;
1623         }
1624
1625         /**
1626          * Set the displayed file version
1627          *
1628          * @param File|null $file
1629          * @return mixed Previous value
1630          */
1631         public function setFileVersion( $file ) {
1632                 $val = null;
1633                 if ( $file instanceof File && $file->exists() ) {
1634                         $val = [ 'time' => $file->getTimestamp(), 'sha1' => $file->getSha1() ];
1635                 }
1636                 return wfSetVar( $this->mFileVersion, $val, true );
1637         }
1638
1639         /**
1640          * Get the displayed file version
1641          *
1642          * @return array|null ('time' => MW timestamp, 'sha1' => sha1)
1643          */
1644         public function getFileVersion() {
1645                 return $this->mFileVersion;
1646         }
1647
1648         /**
1649          * Get the templates used on this page
1650          *
1651          * @return array (namespace => dbKey => revId)
1652          * @since 1.18
1653          */
1654         public function getTemplateIds() {
1655                 return $this->mTemplateIds;
1656         }
1657
1658         /**
1659          * Get the files used on this page
1660          *
1661          * @return array (dbKey => array('time' => MW timestamp or null, 'sha1' => sha1 or ''))
1662          * @since 1.18
1663          */
1664         public function getFileSearchOptions() {
1665                 return $this->mImageTimeKeys;
1666         }
1667
1668         /**
1669          * Convert wikitext to HTML and add it to the buffer
1670          * Default assumes that the current page title will be used.
1671          *
1672          * @param string $text
1673          * @param bool $linestart Is this the start of a line?
1674          * @param bool $interface Is this text in the user interface language?
1675          * @throws MWException
1676          */
1677         public function addWikiText( $text, $linestart = true, $interface = true ) {
1678                 $title = $this->getTitle(); // Work around E_STRICT
1679                 if ( !$title ) {
1680                         throw new MWException( 'Title is null' );
1681                 }
1682                 $this->addWikiTextTitle( $text, $title, $linestart, /*tidy*/false, $interface );
1683         }
1684
1685         /**
1686          * Add wikitext with a custom Title object
1687          *
1688          * @param string $text Wikitext
1689          * @param Title $title
1690          * @param bool $linestart Is this the start of a line?
1691          */
1692         public function addWikiTextWithTitle( $text, Title $title, $linestart = true ) {
1693                 $this->addWikiTextTitle( $text, $title, $linestart );
1694         }
1695
1696         /**
1697          * Add wikitext with a custom Title object and tidy enabled.
1698          *
1699          * @param string $text Wikitext
1700          * @param Title $title
1701          * @param bool $linestart Is this the start of a line?
1702          */
1703         function addWikiTextTitleTidy( $text, Title $title, $linestart = true ) {
1704                 $this->addWikiTextTitle( $text, $title, $linestart, true );
1705         }
1706
1707         /**
1708          * Add wikitext with tidy enabled
1709          *
1710          * @param string $text Wikitext
1711          * @param bool $linestart Is this the start of a line?
1712          */
1713         public function addWikiTextTidy( $text, $linestart = true ) {
1714                 $title = $this->getTitle();
1715                 $this->addWikiTextTitleTidy( $text, $title, $linestart );
1716         }
1717
1718         /**
1719          * Add wikitext with a custom Title object
1720          *
1721          * @param string $text Wikitext
1722          * @param Title $title
1723          * @param bool $linestart Is this the start of a line?
1724          * @param bool $tidy Whether to use tidy
1725          * @param bool $interface Whether it is an interface message
1726          *   (for example disables conversion)
1727          */
1728         public function addWikiTextTitle( $text, Title $title, $linestart,
1729                 $tidy = false, $interface = false
1730         ) {
1731                 global $wgParser;
1732
1733                 $popts = $this->parserOptions();
1734                 $oldTidy = $popts->setTidy( $tidy );
1735                 $popts->setInterfaceMessage( (bool)$interface );
1736
1737                 $parserOutput = $wgParser->getFreshParser()->parse(
1738                         $text, $title, $popts,
1739                         $linestart, true, $this->mRevisionId
1740                 );
1741
1742                 $popts->setTidy( $oldTidy );
1743
1744                 $this->addParserOutput( $parserOutput, [
1745                         'enableSectionEditLinks' => false,
1746                 ] );
1747         }
1748
1749         /**
1750          * Add all metadata associated with a ParserOutput object, but without the actual HTML. This
1751          * includes categories, language links, ResourceLoader modules, effects of certain magic words,
1752          * and so on.
1753          *
1754          * @since 1.24
1755          * @param ParserOutput $parserOutput
1756          */
1757         public function addParserOutputMetadata( $parserOutput ) {
1758                 $this->mLanguageLinks =
1759                         array_merge( $this->mLanguageLinks, $parserOutput->getLanguageLinks() );
1760                 $this->addCategoryLinks( $parserOutput->getCategories() );
1761                 $this->setIndicators( $parserOutput->getIndicators() );
1762                 $this->mNewSectionLink = $parserOutput->getNewSection();
1763                 $this->mHideNewSectionLink = $parserOutput->getHideNewSection();
1764
1765                 if ( !$parserOutput->isCacheable() ) {
1766                         $this->enableClientCache( false );
1767                 }
1768                 $this->mNoGallery = $parserOutput->getNoGallery();
1769                 $this->mHeadItems = array_merge( $this->mHeadItems, $parserOutput->getHeadItems() );
1770                 $this->addModules( $parserOutput->getModules() );
1771                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1772                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1773                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1774                 $this->mPreventClickjacking = $this->mPreventClickjacking
1775                         || $parserOutput->preventClickjacking();
1776
1777                 // Template versioning...
1778                 foreach ( (array)$parserOutput->getTemplateIds() as $ns => $dbks ) {
1779                         if ( isset( $this->mTemplateIds[$ns] ) ) {
1780                                 $this->mTemplateIds[$ns] = $dbks + $this->mTemplateIds[$ns];
1781                         } else {
1782                                 $this->mTemplateIds[$ns] = $dbks;
1783                         }
1784                 }
1785                 // File versioning...
1786                 foreach ( (array)$parserOutput->getFileSearchOptions() as $dbk => $data ) {
1787                         $this->mImageTimeKeys[$dbk] = $data;
1788                 }
1789
1790                 // Hooks registered in the object
1791                 $parserOutputHooks = $this->getConfig()->get( 'ParserOutputHooks' );
1792                 foreach ( $parserOutput->getOutputHooks() as $hookInfo ) {
1793                         list( $hookName, $data ) = $hookInfo;
1794                         if ( isset( $parserOutputHooks[$hookName] ) ) {
1795                                 $parserOutputHooks[$hookName]( $this, $parserOutput, $data );
1796                         }
1797                 }
1798
1799                 // Enable OOUI if requested via ParserOutput
1800                 if ( $parserOutput->getEnableOOUI() ) {
1801                         $this->enableOOUI();
1802                 }
1803
1804                 // Include parser limit report
1805                 if ( !$this->limitReportJSData ) {
1806                         $this->limitReportJSData = $parserOutput->getLimitReportJSData();
1807                 }
1808
1809                 // Link flags are ignored for now, but may in the future be
1810                 // used to mark individual language links.
1811                 $linkFlags = [];
1812                 // Avoid PHP 7.1 warning of passing $this by reference
1813                 $outputPage = $this;
1814                 Hooks::run( 'LanguageLinks', [ $this->getTitle(), &$this->mLanguageLinks, &$linkFlags ] );
1815                 Hooks::runWithoutAbort( 'OutputPageParserOutput', [ &$outputPage, $parserOutput ] );
1816
1817                 // This check must be after 'OutputPageParserOutput' runs in addParserOutputMetadata
1818                 // so that extensions may modify ParserOutput to toggle TOC.
1819                 // This cannot be moved to addParserOutputText because that is not
1820                 // called by EditPage for Preview.
1821                 if ( $parserOutput->getTOCHTML() ) {
1822                         $this->mEnableTOC = true;
1823                 }
1824         }
1825
1826         /**
1827          * Add the HTML and enhancements for it (like ResourceLoader modules) associated with a
1828          * ParserOutput object, without any other metadata.
1829          *
1830          * @since 1.24
1831          * @param ParserOutput $parserOutput
1832          * @param array $poOptions Options to ParserOutput::getText()
1833          */
1834         public function addParserOutputContent( $parserOutput, $poOptions = [] ) {
1835                 $this->addParserOutputText( $parserOutput, $poOptions );
1836
1837                 $this->addModules( $parserOutput->getModules() );
1838                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1839                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1840
1841                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1842         }
1843
1844         /**
1845          * Add the HTML associated with a ParserOutput object, without any metadata.
1846          *
1847          * @since 1.24
1848          * @param ParserOutput $parserOutput
1849          * @param array $poOptions Options to ParserOutput::getText()
1850          */
1851         public function addParserOutputText( $parserOutput, $poOptions = [] ) {
1852                 $text = $parserOutput->getText( $poOptions );
1853                 // Avoid PHP 7.1 warning of passing $this by reference
1854                 $outputPage = $this;
1855                 Hooks::runWithoutAbort( 'OutputPageBeforeHTML', [ &$outputPage, &$text ] );
1856                 $this->addHTML( $text );
1857         }
1858
1859         /**
1860          * Add everything from a ParserOutput object.
1861          *
1862          * @param ParserOutput $parserOutput
1863          * @param array $poOptions Options to ParserOutput::getText()
1864          */
1865         function addParserOutput( $parserOutput, $poOptions = [] ) {
1866                 $this->addParserOutputMetadata( $parserOutput );
1867                 $this->addParserOutputText( $parserOutput, $poOptions );
1868         }
1869
1870         /**
1871          * Add the output of a QuickTemplate to the output buffer
1872          *
1873          * @param QuickTemplate &$template
1874          */
1875         public function addTemplate( &$template ) {
1876                 $this->addHTML( $template->getHTML() );
1877         }
1878
1879         /**
1880          * Parse wikitext and return the HTML.
1881          *
1882          * @param string $text
1883          * @param bool $linestart Is this the start of a line?
1884          * @param bool $interface Use interface language ($wgLang instead of
1885          *   $wgContLang) while parsing language sensitive magic words like GRAMMAR and PLURAL.
1886          *   This also disables LanguageConverter.
1887          * @param Language|null $language Target language object, will override $interface
1888          * @throws MWException
1889          * @return string HTML
1890          */
1891         public function parse( $text, $linestart = true, $interface = false, $language = null ) {
1892                 global $wgParser;
1893
1894                 if ( is_null( $this->getTitle() ) ) {
1895                         throw new MWException( 'Empty $mTitle in ' . __METHOD__ );
1896                 }
1897
1898                 $popts = $this->parserOptions();
1899                 if ( $interface ) {
1900                         $popts->setInterfaceMessage( true );
1901                 }
1902                 if ( $language !== null ) {
1903                         $oldLang = $popts->setTargetLanguage( $language );
1904                 }
1905
1906                 $parserOutput = $wgParser->getFreshParser()->parse(
1907                         $text, $this->getTitle(), $popts,
1908                         $linestart, true, $this->mRevisionId
1909                 );
1910
1911                 if ( $interface ) {
1912                         $popts->setInterfaceMessage( false );
1913                 }
1914                 if ( $language !== null ) {
1915                         $popts->setTargetLanguage( $oldLang );
1916                 }
1917
1918                 return $parserOutput->getText( [
1919                         'enableSectionEditLinks' => false,
1920                 ] );
1921         }
1922
1923         /**
1924          * Parse wikitext, strip paragraphs, and return the HTML.
1925          *
1926          * @param string $text
1927          * @param bool $linestart Is this the start of a line?
1928          * @param bool $interface Use interface language ($wgLang instead of
1929          *   $wgContLang) while parsing language sensitive magic
1930          *   words like GRAMMAR and PLURAL
1931          * @return string HTML
1932          */
1933         public function parseInline( $text, $linestart = true, $interface = false ) {
1934                 $parsed = $this->parse( $text, $linestart, $interface );
1935                 return Parser::stripOuterParagraph( $parsed );
1936         }
1937
1938         /**
1939          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header
1940          *
1941          * @param int $maxage Maximum cache time on the CDN, in seconds.
1942          */
1943         public function setCdnMaxage( $maxage ) {
1944                 $this->mCdnMaxage = min( $maxage, $this->mCdnMaxageLimit );
1945         }
1946
1947         /**
1948          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header to $maxage if that is
1949          * lower than the current s-maxage.  Either way, $maxage is now an upper limit on s-maxage, so
1950          * that future calls to setCdnMaxage() will no longer be able to raise the s-maxage above
1951          * $maxage.
1952          *
1953          * @param int $maxage Maximum cache time on the CDN, in seconds
1954          * @since 1.27
1955          */
1956         public function lowerCdnMaxage( $maxage ) {
1957                 $this->mCdnMaxageLimit = min( $maxage, $this->mCdnMaxageLimit );
1958                 $this->setCdnMaxage( $this->mCdnMaxage );
1959         }
1960
1961         /**
1962          * Get TTL in [$minTTL,$maxTTL] in pass it to lowerCdnMaxage()
1963          *
1964          * This sets and returns $minTTL if $mtime is false or null. Otherwise,
1965          * the TTL is higher the older the $mtime timestamp is. Essentially, the
1966          * TTL is 90% of the age of the object, subject to the min and max.
1967          *
1968          * @param string|int|float|bool|null $mtime Last-Modified timestamp
1969          * @param int $minTTL Minimum TTL in seconds [default: 1 minute]
1970          * @param int $maxTTL Maximum TTL in seconds [default: $wgSquidMaxage]
1971          * @return int TTL in seconds passed to lowerCdnMaxage() (may not be the same as the new
1972          *  s-maxage)
1973          * @since 1.28
1974          */
1975         public function adaptCdnTTL( $mtime, $minTTL = 0, $maxTTL = 0 ) {
1976                 $minTTL = $minTTL ?: IExpiringStore::TTL_MINUTE;
1977                 $maxTTL = $maxTTL ?: $this->getConfig()->get( 'SquidMaxage' );
1978
1979                 if ( $mtime === null || $mtime === false ) {
1980                         return $minTTL; // entity does not exist
1981                 }
1982
1983                 $age = time() - wfTimestamp( TS_UNIX, $mtime );
1984                 $adaptiveTTL = max( 0.9 * $age, $minTTL );
1985                 $adaptiveTTL = min( $adaptiveTTL, $maxTTL );
1986
1987                 $this->lowerCdnMaxage( (int)$adaptiveTTL );
1988
1989                 return $adaptiveTTL;
1990         }
1991
1992         /**
1993          * Use enableClientCache(false) to force it to send nocache headers
1994          *
1995          * @param bool|null $state New value, or null to not set the value
1996          *
1997          * @return bool Old value
1998          */
1999         public function enableClientCache( $state ) {
2000                 return wfSetVar( $this->mEnableClientCache, $state );
2001         }
2002
2003         /**
2004          * Get the list of cookie names that will influence the cache
2005          *
2006          * @return array
2007          */
2008         function getCacheVaryCookies() {
2009                 static $cookies;
2010                 if ( $cookies === null ) {
2011                         $config = $this->getConfig();
2012                         $cookies = array_merge(
2013                                 SessionManager::singleton()->getVaryCookies(),
2014                                 [
2015                                         'forceHTTPS',
2016                                 ],
2017                                 $config->get( 'CacheVaryCookies' )
2018                         );
2019                         Hooks::run( 'GetCacheVaryCookies', [ $this, &$cookies ] );
2020                 }
2021                 return $cookies;
2022         }
2023
2024         /**
2025          * Check if the request has a cache-varying cookie header
2026          * If it does, it's very important that we don't allow public caching
2027          *
2028          * @return bool
2029          */
2030         function haveCacheVaryCookies() {
2031                 $request = $this->getRequest();
2032                 foreach ( $this->getCacheVaryCookies() as $cookieName ) {
2033                         if ( $request->getCookie( $cookieName, '', '' ) !== '' ) {
2034                                 wfDebug( __METHOD__ . ": found $cookieName\n" );
2035                                 return true;
2036                         }
2037                 }
2038                 wfDebug( __METHOD__ . ": no cache-varying cookies found\n" );
2039                 return false;
2040         }
2041
2042         /**
2043          * Add an HTTP header that will influence on the cache
2044          *
2045          * @param string $header Header name
2046          * @param string[]|null $option Options for the Key header. See
2047          * https://datatracker.ietf.org/doc/draft-fielding-http-key/
2048          * for the list of valid options.
2049          */
2050         public function addVaryHeader( $header, array $option = null ) {
2051                 if ( !array_key_exists( $header, $this->mVaryHeader ) ) {
2052                         $this->mVaryHeader[$header] = [];
2053                 }
2054                 if ( !is_array( $option ) ) {
2055                         $option = [];
2056                 }
2057                 $this->mVaryHeader[$header] =
2058                         array_unique( array_merge( $this->mVaryHeader[$header], $option ) );
2059         }
2060
2061         /**
2062          * Return a Vary: header on which to vary caches. Based on the keys of $mVaryHeader,
2063          * such as Accept-Encoding or Cookie
2064          *
2065          * @return string
2066          */
2067         public function getVaryHeader() {
2068                 // If we vary on cookies, let's make sure it's always included here too.
2069                 if ( $this->getCacheVaryCookies() ) {
2070                         $this->addVaryHeader( 'Cookie' );
2071                 }
2072
2073                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2074                         $this->addVaryHeader( $header, $options );
2075                 }
2076                 return 'Vary: ' . implode( ', ', array_keys( $this->mVaryHeader ) );
2077         }
2078
2079         /**
2080          * Add an HTTP Link: header
2081          *
2082          * @param string $header Header value
2083          */
2084         public function addLinkHeader( $header ) {
2085                 $this->mLinkHeader[] = $header;
2086         }
2087
2088         /**
2089          * Return a Link: header. Based on the values of $mLinkHeader.
2090          *
2091          * @return string
2092          */
2093         public function getLinkHeader() {
2094                 if ( !$this->mLinkHeader ) {
2095                         return false;
2096                 }
2097
2098                 return 'Link: ' . implode( ',', $this->mLinkHeader );
2099         }
2100
2101         /**
2102          * Get a complete Key header
2103          *
2104          * @return string
2105          */
2106         public function getKeyHeader() {
2107                 $cvCookies = $this->getCacheVaryCookies();
2108
2109                 $cookiesOption = [];
2110                 foreach ( $cvCookies as $cookieName ) {
2111                         $cookiesOption[] = 'param=' . $cookieName;
2112                 }
2113                 $this->addVaryHeader( 'Cookie', $cookiesOption );
2114
2115                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2116                         $this->addVaryHeader( $header, $options );
2117                 }
2118
2119                 $headers = [];
2120                 foreach ( $this->mVaryHeader as $header => $option ) {
2121                         $newheader = $header;
2122                         if ( is_array( $option ) && count( $option ) > 0 ) {
2123                                 $newheader .= ';' . implode( ';', $option );
2124                         }
2125                         $headers[] = $newheader;
2126                 }
2127                 $key = 'Key: ' . implode( ',', $headers );
2128
2129                 return $key;
2130         }
2131
2132         /**
2133          * T23672: Add Accept-Language to Vary and Key headers if there's no 'variant' parameter in GET.
2134          *
2135          * For example:
2136          *   /w/index.php?title=Main_page will vary based on Accept-Language; but
2137          *   /w/index.php?title=Main_page&variant=zh-cn will not.
2138          */
2139         private function addAcceptLanguage() {
2140                 $title = $this->getTitle();
2141                 if ( !$title instanceof Title ) {
2142                         return;
2143                 }
2144
2145                 $lang = $title->getPageLanguage();
2146                 if ( !$this->getRequest()->getCheck( 'variant' ) && $lang->hasVariants() ) {
2147                         $variants = $lang->getVariants();
2148                         $aloption = [];
2149                         foreach ( $variants as $variant ) {
2150                                 if ( $variant === $lang->getCode() ) {
2151                                         continue;
2152                                 }
2153
2154                                 $aloption[] = "substr=$variant";
2155
2156                                 // IE and some other browsers use BCP 47 standards in their Accept-Language header,
2157                                 // like "zh-CN" or "zh-Hant".  We should handle these too.
2158                                 $variantBCP47 = LanguageCode::bcp47( $variant );
2159                                 if ( $variantBCP47 !== $variant ) {
2160                                         $aloption[] = "substr=$variantBCP47";
2161                                 }
2162                         }
2163                         $this->addVaryHeader( 'Accept-Language', $aloption );
2164                 }
2165         }
2166
2167         /**
2168          * Set a flag which will cause an X-Frame-Options header appropriate for
2169          * edit pages to be sent. The header value is controlled by
2170          * $wgEditPageFrameOptions.
2171          *
2172          * This is the default for special pages. If you display a CSRF-protected
2173          * form on an ordinary view page, then you need to call this function.
2174          *
2175          * @param bool $enable
2176          */
2177         public function preventClickjacking( $enable = true ) {
2178                 $this->mPreventClickjacking = $enable;
2179         }
2180
2181         /**
2182          * Turn off frame-breaking. Alias for $this->preventClickjacking(false).
2183          * This can be called from pages which do not contain any CSRF-protected
2184          * HTML form.
2185          */
2186         public function allowClickjacking() {
2187                 $this->mPreventClickjacking = false;
2188         }
2189
2190         /**
2191          * Get the prevent-clickjacking flag
2192          *
2193          * @since 1.24
2194          * @return bool
2195          */
2196         public function getPreventClickjacking() {
2197                 return $this->mPreventClickjacking;
2198         }
2199
2200         /**
2201          * Get the X-Frame-Options header value (without the name part), or false
2202          * if there isn't one. This is used by Skin to determine whether to enable
2203          * JavaScript frame-breaking, for clients that don't support X-Frame-Options.
2204          *
2205          * @return string|false
2206          */
2207         public function getFrameOptions() {
2208                 $config = $this->getConfig();
2209                 if ( $config->get( 'BreakFrames' ) ) {
2210                         return 'DENY';
2211                 } elseif ( $this->mPreventClickjacking && $config->get( 'EditPageFrameOptions' ) ) {
2212                         return $config->get( 'EditPageFrameOptions' );
2213                 }
2214                 return false;
2215         }
2216
2217         /**
2218          * Send cache control HTTP headers
2219          */
2220         public function sendCacheControl() {
2221                 $response = $this->getRequest()->response();
2222                 $config = $this->getConfig();
2223
2224                 $this->addVaryHeader( 'Cookie' );
2225                 $this->addAcceptLanguage();
2226
2227                 # don't serve compressed data to clients who can't handle it
2228                 # maintain different caches for logged-in users and non-logged in ones
2229                 $response->header( $this->getVaryHeader() );
2230
2231                 if ( $config->get( 'UseKeyHeader' ) ) {
2232                         $response->header( $this->getKeyHeader() );
2233                 }
2234
2235                 if ( $this->mEnableClientCache ) {
2236                         if (
2237                                 $config->get( 'UseSquid' ) &&
2238                                 !$response->hasCookies() &&
2239                                 !SessionManager::getGlobalSession()->isPersistent() &&
2240                                 !$this->isPrintable() &&
2241                                 $this->mCdnMaxage != 0 &&
2242                                 !$this->haveCacheVaryCookies()
2243                         ) {
2244                                 if ( $config->get( 'UseESI' ) ) {
2245                                         # We'll purge the proxy cache explicitly, but require end user agents
2246                                         # to revalidate against the proxy on each visit.
2247                                         # Surrogate-Control controls our CDN, Cache-Control downstream caches
2248                                         wfDebug( __METHOD__ .
2249                                                 ": proxy caching with ESI; {$this->mLastModified} **", 'private' );
2250                                         # start with a shorter timeout for initial testing
2251                                         # header( 'Surrogate-Control: max-age=2678400+2678400, content="ESI/1.0"');
2252                                         $response->header(
2253                                                 "Surrogate-Control: max-age={$config->get( 'SquidMaxage' )}" .
2254                                                 "+{$this->mCdnMaxage}, content=\"ESI/1.0\""
2255                                         );
2256                                         $response->header( 'Cache-Control: s-maxage=0, must-revalidate, max-age=0' );
2257                                 } else {
2258                                         # We'll purge the proxy cache for anons explicitly, but require end user agents
2259                                         # to revalidate against the proxy on each visit.
2260                                         # IMPORTANT! The CDN needs to replace the Cache-Control header with
2261                                         # Cache-Control: s-maxage=0, must-revalidate, max-age=0
2262                                         wfDebug( __METHOD__ .
2263                                                 ": local proxy caching; {$this->mLastModified} **", 'private' );
2264                                         # start with a shorter timeout for initial testing
2265                                         # header( "Cache-Control: s-maxage=2678400, must-revalidate, max-age=0" );
2266                                         $response->header( "Cache-Control: " .
2267                                                 "s-maxage={$this->mCdnMaxage}, must-revalidate, max-age=0" );
2268                                 }
2269                         } else {
2270                                 # We do want clients to cache if they can, but they *must* check for updates
2271                                 # on revisiting the page.
2272                                 wfDebug( __METHOD__ . ": private caching; {$this->mLastModified} **", 'private' );
2273                                 $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2274                                 $response->header( "Cache-Control: private, must-revalidate, max-age=0" );
2275                         }
2276                         if ( $this->mLastModified ) {
2277                                 $response->header( "Last-Modified: {$this->mLastModified}" );
2278                         }
2279                 } else {
2280                         wfDebug( __METHOD__ . ": no caching **", 'private' );
2281
2282                         # In general, the absence of a last modified header should be enough to prevent
2283                         # the client from using its cache. We send a few other things just to make sure.
2284                         $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2285                         $response->header( 'Cache-Control: no-cache, no-store, max-age=0, must-revalidate' );
2286                         $response->header( 'Pragma: no-cache' );
2287                 }
2288         }
2289
2290         /**
2291          * Transfer styles and JavaScript modules from skin.
2292          *
2293          * @param Skin $sk to load modules for
2294          */
2295         public function loadSkinModules( $sk ) {
2296                 foreach ( $sk->getDefaultModules() as $group => $modules ) {
2297                         if ( $group === 'styles' ) {
2298                                 foreach ( $modules as $key => $moduleMembers ) {
2299                                         $this->addModuleStyles( $moduleMembers );
2300                                 }
2301                         } else {
2302                                 $this->addModules( $modules );
2303                         }
2304                 }
2305         }
2306
2307         /**
2308          * Finally, all the text has been munged and accumulated into
2309          * the object, let's actually output it:
2310          *
2311          * @param bool $return Set to true to get the result as a string rather than sending it
2312          * @return string|null
2313          * @throws Exception
2314          * @throws FatalError
2315          * @throws MWException
2316          */
2317         public function output( $return = false ) {
2318                 global $wgContLang;
2319
2320                 if ( $this->mDoNothing ) {
2321                         return $return ? '' : null;
2322                 }
2323
2324                 $response = $this->getRequest()->response();
2325                 $config = $this->getConfig();
2326
2327                 if ( $this->mRedirect != '' ) {
2328                         # Standards require redirect URLs to be absolute
2329                         $this->mRedirect = wfExpandUrl( $this->mRedirect, PROTO_CURRENT );
2330
2331                         $redirect = $this->mRedirect;
2332                         $code = $this->mRedirectCode;
2333
2334                         if ( Hooks::run( "BeforePageRedirect", [ $this, &$redirect, &$code ] ) ) {
2335                                 if ( $code == '301' || $code == '303' ) {
2336                                         if ( !$config->get( 'DebugRedirects' ) ) {
2337                                                 $response->statusHeader( $code );
2338                                         }
2339                                         $this->mLastModified = wfTimestamp( TS_RFC2822 );
2340                                 }
2341                                 if ( $config->get( 'VaryOnXFP' ) ) {
2342                                         $this->addVaryHeader( 'X-Forwarded-Proto' );
2343                                 }
2344                                 $this->sendCacheControl();
2345
2346                                 $response->header( "Content-Type: text/html; charset=utf-8" );
2347                                 if ( $config->get( 'DebugRedirects' ) ) {
2348                                         $url = htmlspecialchars( $redirect );
2349                                         print "<!DOCTYPE html>\n<html>\n<head>\n<title>Redirect</title>\n</head>\n<body>\n";
2350                                         print "<p>Location: <a href=\"$url\">$url</a></p>\n";
2351                                         print "</body>\n</html>\n";
2352                                 } else {
2353                                         $response->header( 'Location: ' . $redirect );
2354                                 }
2355                         }
2356
2357                         return $return ? '' : null;
2358                 } elseif ( $this->mStatusCode ) {
2359                         $response->statusHeader( $this->mStatusCode );
2360                 }
2361
2362                 # Buffer output; final headers may depend on later processing
2363                 ob_start();
2364
2365                 $response->header( 'Content-type: ' . $config->get( 'MimeType' ) . '; charset=UTF-8' );
2366                 $response->header( 'Content-language: ' . $wgContLang->getHtmlCode() );
2367
2368                 if ( !$this->mArticleBodyOnly ) {
2369                         $sk = $this->getSkin();
2370
2371                         if ( $sk->shouldPreloadLogo() ) {
2372                                 $this->addLogoPreloadLinkHeaders();
2373                         }
2374                 }
2375
2376                 $linkHeader = $this->getLinkHeader();
2377                 if ( $linkHeader ) {
2378                         $response->header( $linkHeader );
2379                 }
2380
2381                 // Prevent framing, if requested
2382                 $frameOptions = $this->getFrameOptions();
2383                 if ( $frameOptions ) {
2384                         $response->header( "X-Frame-Options: $frameOptions" );
2385                 }
2386
2387                 ContentSecurityPolicy::sendHeaders( $this );
2388
2389                 if ( $this->mArticleBodyOnly ) {
2390                         echo $this->mBodytext;
2391                 } else {
2392                         // Enable safe mode if requested (T152169)
2393                         if ( $this->getRequest()->getBool( 'safemode' ) ) {
2394                                 $this->disallowUserJs();
2395                         }
2396
2397                         $sk = $this->getSkin();
2398                         $this->loadSkinModules( $sk );
2399
2400                         MWDebug::addModules( $this );
2401
2402                         // Avoid PHP 7.1 warning of passing $this by reference
2403                         $outputPage = $this;
2404                         // Hook that allows last minute changes to the output page, e.g.
2405                         // adding of CSS or Javascript by extensions.
2406                         Hooks::runWithoutAbort( 'BeforePageDisplay', [ &$outputPage, &$sk ] );
2407
2408                         try {
2409                                 $sk->outputPage();
2410                         } catch ( Exception $e ) {
2411                                 ob_end_clean(); // bug T129657
2412                                 throw $e;
2413                         }
2414                 }
2415
2416                 try {
2417                         // This hook allows last minute changes to final overall output by modifying output buffer
2418                         Hooks::runWithoutAbort( 'AfterFinalPageOutput', [ $this ] );
2419                 } catch ( Exception $e ) {
2420                         ob_end_clean(); // bug T129657
2421                         throw $e;
2422                 }
2423
2424                 $this->sendCacheControl();
2425
2426                 if ( $return ) {
2427                         return ob_get_clean();
2428                 } else {
2429                         ob_end_flush();
2430                         return null;
2431                 }
2432         }
2433
2434         /**
2435          * Prepare this object to display an error page; disable caching and
2436          * indexing, clear the current text and redirect, set the page's title
2437          * and optionally an custom HTML title (content of the "<title>" tag).
2438          *
2439          * @param string|Message $pageTitle Will be passed directly to setPageTitle()
2440          * @param string|Message $htmlTitle Will be passed directly to setHTMLTitle();
2441          *                   optional, if not passed the "<title>" attribute will be
2442          *                   based on $pageTitle
2443          */
2444         public function prepareErrorPage( $pageTitle, $htmlTitle = false ) {
2445                 $this->setPageTitle( $pageTitle );
2446                 if ( $htmlTitle !== false ) {
2447                         $this->setHTMLTitle( $htmlTitle );
2448                 }
2449                 $this->setRobotPolicy( 'noindex,nofollow' );
2450                 $this->setArticleRelated( false );
2451                 $this->enableClientCache( false );
2452                 $this->mRedirect = '';
2453                 $this->clearSubtitle();
2454                 $this->clearHTML();
2455         }
2456
2457         /**
2458          * Output a standard error page
2459          *
2460          * showErrorPage( 'titlemsg', 'pagetextmsg' );
2461          * showErrorPage( 'titlemsg', 'pagetextmsg', [ 'param1', 'param2' ] );
2462          * showErrorPage( 'titlemsg', $messageObject );
2463          * showErrorPage( $titleMessageObject, $messageObject );
2464          *
2465          * @param string|Message $title Message key (string) for page title, or a Message object
2466          * @param string|Message $msg Message key (string) for page text, or a Message object
2467          * @param array $params Message parameters; ignored if $msg is a Message object
2468          */
2469         public function showErrorPage( $title, $msg, $params = [] ) {
2470                 if ( !$title instanceof Message ) {
2471                         $title = $this->msg( $title );
2472                 }
2473
2474                 $this->prepareErrorPage( $title );
2475
2476                 if ( $msg instanceof Message ) {
2477                         if ( $params !== [] ) {
2478                                 trigger_error( 'Argument ignored: $params. The message parameters argument '
2479                                         . 'is discarded when the $msg argument is a Message object instead of '
2480                                         . 'a string.', E_USER_NOTICE );
2481                         }
2482                         $this->addHTML( $msg->parseAsBlock() );
2483                 } else {
2484                         $this->addWikiMsgArray( $msg, $params );
2485                 }
2486
2487                 $this->returnToMain();
2488         }
2489
2490         /**
2491          * Output a standard permission error page
2492          *
2493          * @param array $errors Error message keys or [key, param...] arrays
2494          * @param string|null $action Action that was denied or null if unknown
2495          */
2496         public function showPermissionsErrorPage( array $errors, $action = null ) {
2497                 foreach ( $errors as $key => $error ) {
2498                         $errors[$key] = (array)$error;
2499                 }
2500
2501                 // For some action (read, edit, create and upload), display a "login to do this action"
2502                 // error if all of the following conditions are met:
2503                 // 1. the user is not logged in
2504                 // 2. the only error is insufficient permissions (i.e. no block or something else)
2505                 // 3. the error can be avoided simply by logging in
2506                 if ( in_array( $action, [ 'read', 'edit', 'createpage', 'createtalk', 'upload' ] )
2507                         && $this->getUser()->isAnon() && count( $errors ) == 1 && isset( $errors[0][0] )
2508                         && ( $errors[0][0] == 'badaccess-groups' || $errors[0][0] == 'badaccess-group0' )
2509                         && ( User::groupHasPermission( 'user', $action )
2510                         || User::groupHasPermission( 'autoconfirmed', $action ) )
2511                 ) {
2512                         $displayReturnto = null;
2513
2514                         # Due to T34276, if a user does not have read permissions,
2515                         # $this->getTitle() will just give Special:Badtitle, which is
2516                         # not especially useful as a returnto parameter. Use the title
2517                         # from the request instead, if there was one.
2518                         $request = $this->getRequest();
2519                         $returnto = Title::newFromText( $request->getVal( 'title', '' ) );
2520                         if ( $action == 'edit' ) {
2521                                 $msg = 'whitelistedittext';
2522                                 $displayReturnto = $returnto;
2523                         } elseif ( $action == 'createpage' || $action == 'createtalk' ) {
2524                                 $msg = 'nocreatetext';
2525                         } elseif ( $action == 'upload' ) {
2526                                 $msg = 'uploadnologintext';
2527                         } else { # Read
2528                                 $msg = 'loginreqpagetext';
2529                                 $displayReturnto = Title::newMainPage();
2530                         }
2531
2532                         $query = [];
2533
2534                         if ( $returnto ) {
2535                                 $query['returnto'] = $returnto->getPrefixedText();
2536
2537                                 if ( !$request->wasPosted() ) {
2538                                         $returntoquery = $request->getValues();
2539                                         unset( $returntoquery['title'] );
2540                                         unset( $returntoquery['returnto'] );
2541                                         unset( $returntoquery['returntoquery'] );
2542                                         $query['returntoquery'] = wfArrayToCgi( $returntoquery );
2543                                 }
2544                         }
2545                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
2546                         $loginLink = $linkRenderer->makeKnownLink(
2547                                 SpecialPage::getTitleFor( 'Userlogin' ),
2548                                 $this->msg( 'loginreqlink' )->text(),
2549                                 [],
2550                                 $query
2551                         );
2552
2553                         $this->prepareErrorPage( $this->msg( 'loginreqtitle' ) );
2554                         $this->addHTML( $this->msg( $msg )->rawParams( $loginLink )->parse() );
2555
2556                         # Don't return to a page the user can't read otherwise
2557                         # we'll end up in a pointless loop
2558                         if ( $displayReturnto && $displayReturnto->userCan( 'read', $this->getUser() ) ) {
2559                                 $this->returnToMain( null, $displayReturnto );
2560                         }
2561                 } else {
2562                         $this->prepareErrorPage( $this->msg( 'permissionserrors' ) );
2563                         $this->addWikiText( $this->formatPermissionsErrorMessage( $errors, $action ) );
2564                 }
2565         }
2566
2567         /**
2568          * Display an error page indicating that a given version of MediaWiki is
2569          * required to use it
2570          *
2571          * @param mixed $version The version of MediaWiki needed to use the page
2572          */
2573         public function versionRequired( $version ) {
2574                 $this->prepareErrorPage( $this->msg( 'versionrequired', $version ) );
2575
2576                 $this->addWikiMsg( 'versionrequiredtext', $version );
2577                 $this->returnToMain();
2578         }
2579
2580         /**
2581          * Format a list of error messages
2582          *
2583          * @param array $errors Array of arrays returned by Title::getUserPermissionsErrors
2584          * @param string|null $action Action that was denied or null if unknown
2585          * @return string The wikitext error-messages, formatted into a list.
2586          */
2587         public function formatPermissionsErrorMessage( array $errors, $action = null ) {
2588                 if ( $action == null ) {
2589                         $text = $this->msg( 'permissionserrorstext', count( $errors ) )->plain() . "\n\n";
2590                 } else {
2591                         $action_desc = $this->msg( "action-$action" )->plain();
2592                         $text = $this->msg(
2593                                 'permissionserrorstext-withaction',
2594                                 count( $errors ),
2595                                 $action_desc
2596                         )->plain() . "\n\n";
2597                 }
2598
2599                 if ( count( $errors ) > 1 ) {
2600                         $text .= '<ul class="permissions-errors">' . "\n";
2601
2602                         foreach ( $errors as $error ) {
2603                                 $text .= '<li>';
2604                                 $text .= $this->msg( ...$error )->plain();
2605                                 $text .= "</li>\n";
2606                         }
2607                         $text .= '</ul>';
2608                 } else {
2609                         $text .= "<div class=\"permissions-errors\">\n" .
2610                                         $this->msg( ...reset( $errors ) )->plain() .
2611                                         "\n</div>";
2612                 }
2613
2614                 return $text;
2615         }
2616
2617         /**
2618          * Show a warning about replica DB lag
2619          *
2620          * If the lag is higher than $wgSlaveLagCritical seconds,
2621          * then the warning is a bit more obvious. If the lag is
2622          * lower than $wgSlaveLagWarning, then no warning is shown.
2623          *
2624          * @param int $lag Slave lag
2625          */
2626         public function showLagWarning( $lag ) {
2627                 $config = $this->getConfig();
2628                 if ( $lag >= $config->get( 'SlaveLagWarning' ) ) {
2629                         $lag = floor( $lag ); // floor to avoid nano seconds to display
2630                         $message = $lag < $config->get( 'SlaveLagCritical' )
2631                                 ? 'lag-warn-normal'
2632                                 : 'lag-warn-high';
2633                         $wrap = Html::rawElement( 'div', [ 'class' => "mw-{$message}" ], "\n$1\n" );
2634                         $this->wrapWikiMsg( "$wrap\n", [ $message, $this->getLanguage()->formatNum( $lag ) ] );
2635                 }
2636         }
2637
2638         /**
2639          * Output an error page
2640          *
2641          * @note FatalError exception class provides an alternative.
2642          * @param string $message Error to output. Must be escaped for HTML.
2643          */
2644         public function showFatalError( $message ) {
2645                 $this->prepareErrorPage( $this->msg( 'internalerror' ) );
2646
2647                 $this->addHTML( $message );
2648         }
2649
2650         /**
2651          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
2652          */
2653         public function showUnexpectedValueError( $name, $val ) {
2654                 wfDeprecated( __METHOD__, '1.32' );
2655                 $this->showFatalError( $this->msg( 'unexpected', $name, $val )->escaped() );
2656         }
2657
2658         /**
2659          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
2660          */
2661         public function showFileCopyError( $old, $new ) {
2662                 wfDeprecated( __METHOD__, '1.32' );
2663                 $this->showFatalError( $this->msg( 'filecopyerror', $old, $new )->escaped() );
2664         }
2665
2666         /**
2667          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
2668          */
2669         public function showFileRenameError( $old, $new ) {
2670                 wfDeprecated( __METHOD__, '1.32' );
2671                 $this->showFatalError( $this->msg( 'filerenameerror', $old, $new )->escpaed() );
2672         }
2673
2674         /**
2675          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
2676          */
2677         public function showFileDeleteError( $name ) {
2678                 wfDeprecated( __METHOD__, '1.32' );
2679                 $this->showFatalError( $this->msg( 'filedeleteerror', $name )->escaped() );
2680         }
2681
2682         /**
2683          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
2684          */
2685         public function showFileNotFoundError( $name ) {
2686                 wfDeprecated( __METHOD__, '1.32' );
2687                 $this->showFatalError( $this->msg( 'filenotfound', $name )->escaped() );
2688         }
2689
2690         /**
2691          * Add a "return to" link pointing to a specified title
2692          *
2693          * @param Title $title Title to link
2694          * @param array $query Query string parameters
2695          * @param string|null $text Text of the link (input is not escaped)
2696          * @param array $options Options array to pass to Linker
2697          */
2698         public function addReturnTo( $title, array $query = [], $text = null, $options = [] ) {
2699                 $linkRenderer = MediaWikiServices::getInstance()
2700                         ->getLinkRendererFactory()->createFromLegacyOptions( $options );
2701                 $link = $this->msg( 'returnto' )->rawParams(
2702                         $linkRenderer->makeLink( $title, $text, [], $query ) )->escaped();
2703                 $this->addHTML( "<p id=\"mw-returnto\">{$link}</p>\n" );
2704         }
2705
2706         /**
2707          * Add a "return to" link pointing to a specified title,
2708          * or the title indicated in the request, or else the main page
2709          *
2710          * @param mixed|null $unused
2711          * @param Title|string|null $returnto Title or String to return to
2712          * @param string|null $returntoquery Query string for the return to link
2713          */
2714         public function returnToMain( $unused = null, $returnto = null, $returntoquery = null ) {
2715                 if ( $returnto == null ) {
2716                         $returnto = $this->getRequest()->getText( 'returnto' );
2717                 }
2718
2719                 if ( $returntoquery == null ) {
2720                         $returntoquery = $this->getRequest()->getText( 'returntoquery' );
2721                 }
2722
2723                 if ( $returnto === '' ) {
2724                         $returnto = Title::newMainPage();
2725                 }
2726
2727                 if ( is_object( $returnto ) ) {
2728                         $titleObj = $returnto;
2729                 } else {
2730                         $titleObj = Title::newFromText( $returnto );
2731                 }
2732                 // We don't want people to return to external interwiki. That
2733                 // might potentially be used as part of a phishing scheme
2734                 if ( !is_object( $titleObj ) || $titleObj->isExternal() ) {
2735                         $titleObj = Title::newMainPage();
2736                 }
2737
2738                 $this->addReturnTo( $titleObj, wfCgiToArray( $returntoquery ) );
2739         }
2740
2741         private function getRlClientContext() {
2742                 if ( !$this->rlClientContext ) {
2743                         $query = ResourceLoader::makeLoaderQuery(
2744                                 [], // modules; not relevant
2745                                 $this->getLanguage()->getCode(),
2746                                 $this->getSkin()->getSkinName(),
2747                                 $this->getUser()->isLoggedIn() ? $this->getUser()->getName() : null,
2748                                 null, // version; not relevant
2749                                 ResourceLoader::inDebugMode(),
2750                                 null, // only; not relevant
2751                                 $this->isPrintable(),
2752                                 $this->getRequest()->getBool( 'handheld' )
2753                         );
2754                         $this->rlClientContext = new ResourceLoaderContext(
2755                                 $this->getResourceLoader(),
2756                                 new FauxRequest( $query )
2757                         );
2758                         if ( $this->contentOverrideCallbacks ) {
2759                                 $this->rlClientContext = new DerivativeResourceLoaderContext( $this->rlClientContext );
2760                                 $this->rlClientContext->setContentOverrideCallback( function ( Title $title ) {
2761                                         foreach ( $this->contentOverrideCallbacks as $callback ) {
2762                                                 $content = $callback( $title );
2763                                                 if ( $content !== null ) {
2764                                                         return $content;
2765                                                 }
2766                                         }
2767                                         return null;
2768                                 } );
2769                         }
2770                 }
2771                 return $this->rlClientContext;
2772         }
2773
2774         /**
2775          * Call this to freeze the module queue and JS config and create a formatter.
2776          *
2777          * Depending on the Skin, this may get lazy-initialised in either headElement() or
2778          * getBottomScripts(). See SkinTemplate::prepareQuickTemplate(). Calling this too early may
2779          * cause unexpected side-effects since disallowUserJs() may be called at any time to change
2780          * the module filters retroactively. Skins and extension hooks may also add modules until very
2781          * late in the request lifecycle.
2782          *
2783          * @return ResourceLoaderClientHtml
2784          */
2785         public function getRlClient() {
2786                 if ( !$this->rlClient ) {
2787                         $context = $this->getRlClientContext();
2788                         $rl = $this->getResourceLoader();
2789                         $this->addModules( [
2790                                 'user',
2791                                 'user.options',
2792                                 'user.tokens',
2793                         ] );
2794                         $this->addModuleStyles( [
2795                                 'site.styles',
2796                                 'noscript',
2797                                 'user.styles',
2798                         ] );
2799                         $this->getSkin()->setupSkinUserCss( $this );
2800
2801                         // Prepare exempt modules for buildExemptModules()
2802                         $exemptGroups = [ 'site' => [], 'noscript' => [], 'private' => [], 'user' => [] ];
2803                         $exemptStates = [];
2804                         $moduleStyles = $this->getModuleStyles( /*filter*/ true );
2805
2806                         // Preload getTitleInfo for isKnownEmpty calls below and in ResourceLoaderClientHtml
2807                         // Separate user-specific batch for improved cache-hit ratio.
2808                         $userBatch = [ 'user.styles', 'user' ];
2809                         $siteBatch = array_diff( $moduleStyles, $userBatch );
2810                         $dbr = wfGetDB( DB_REPLICA );
2811                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $siteBatch );
2812                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $userBatch );
2813
2814                         // Filter out modules handled by buildExemptModules()
2815                         $moduleStyles = array_filter( $moduleStyles,
2816                                 function ( $name ) use ( $rl, $context, &$exemptGroups, &$exemptStates ) {
2817                                         $module = $rl->getModule( $name );
2818                                         if ( $module ) {
2819                                                 $group = $module->getGroup();
2820                                                 if ( isset( $exemptGroups[$group] ) ) {
2821                                                         $exemptStates[$name] = 'ready';
2822                                                         if ( !$module->isKnownEmpty( $context ) ) {
2823                                                                 // E.g. Don't output empty <styles>
2824                                                                 $exemptGroups[$group][] = $name;
2825                                                         }
2826                                                         return false;
2827                                                 }
2828                                         }
2829                                         return true;
2830                                 }
2831                         );
2832                         $this->rlExemptStyleModules = $exemptGroups;
2833
2834                         $rlClient = new ResourceLoaderClientHtml( $context, [
2835                                 'target' => $this->getTarget(),
2836                                 'nonce' => $this->getCSPNonce(),
2837                                 // When 'safemode', disallowUserJs(), or reduceAllowedModules() is used
2838                                 // to only restrict modules to ORIGIN_CORE (ie. disallow ORIGIN_USER), the list of
2839                                 // modules enqueud for loading on this page is filtered to just those.
2840                                 // However, to make sure we also apply the restriction to dynamic dependencies and
2841                                 // lazy-loaded modules at run-time on the client-side, pass 'safemode' down to the
2842                                 // StartupModule so that the client-side registry will not contain any restricted
2843                                 // modules either. (T152169, T185303)
2844                                 'safemode' => ( $this->getAllowedModules( ResourceLoaderModule::TYPE_COMBINED )
2845                                         <= ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
2846                                 ) ? '1' : null,
2847                         ] );
2848                         $rlClient->setConfig( $this->getJSVars() );
2849                         $rlClient->setModules( $this->getModules( /*filter*/ true ) );
2850                         $rlClient->setModuleStyles( $moduleStyles );
2851                         $rlClient->setModuleScripts( $this->getModuleScripts( /*filter*/ true ) );
2852                         $rlClient->setExemptStates( $exemptStates );
2853                         $this->rlClient = $rlClient;
2854                 }
2855                 return $this->rlClient;
2856         }
2857
2858         /**
2859          * @param Skin $sk The given Skin
2860          * @param bool $includeStyle Unused
2861          * @return string The doctype, opening "<html>", and head element.
2862          */
2863         public function headElement( Skin $sk, $includeStyle = true ) {
2864                 global $wgContLang;
2865
2866                 $userdir = $this->getLanguage()->getDir();
2867                 $sitedir = $wgContLang->getDir();
2868
2869                 $pieces = [];
2870                 $pieces[] = Html::htmlHeader( Sanitizer::mergeAttributes(
2871                         $this->getRlClient()->getDocumentAttributes(),
2872                         $sk->getHtmlElementAttributes()
2873                 ) );
2874                 $pieces[] = Html::openElement( 'head' );
2875
2876                 if ( $this->getHTMLTitle() == '' ) {
2877                         $this->setHTMLTitle( $this->msg( 'pagetitle', $this->getPageTitle() )->inContentLanguage() );
2878                 }
2879
2880                 if ( !Html::isXmlMimeType( $this->getConfig()->get( 'MimeType' ) ) ) {
2881                         // Add <meta charset="UTF-8">
2882                         // This should be before <title> since it defines the charset used by
2883                         // text including the text inside <title>.
2884                         // The spec recommends defining XHTML5's charset using the XML declaration
2885                         // instead of meta.
2886                         // Our XML declaration is output by Html::htmlHeader.
2887                         // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-content-type
2888                         // https://html.spec.whatwg.org/multipage/semantics.html#charset
2889                         $pieces[] = Html::element( 'meta', [ 'charset' => 'UTF-8' ] );
2890                 }
2891
2892                 $pieces[] = Html::element( 'title', null, $this->getHTMLTitle() );
2893                 $pieces[] = $this->getRlClient()->getHeadHtml();
2894                 $pieces[] = $this->buildExemptModules();
2895                 $pieces = array_merge( $pieces, array_values( $this->getHeadLinksArray() ) );
2896                 $pieces = array_merge( $pieces, array_values( $this->mHeadItems ) );
2897
2898                 // Use an IE conditional comment to serve the script only to old IE
2899                 $pieces[] = '<!--[if lt IE 9]>' .
2900                         ResourceLoaderClientHtml::makeLoad(
2901                                 ResourceLoaderContext::newDummyContext(),
2902                                 [ 'html5shiv' ],
2903                                 ResourceLoaderModule::TYPE_SCRIPTS,
2904                                 [ 'sync' => true ],
2905                                 $this->getCSPNonce()
2906                         ) .
2907                         '<![endif]-->';
2908
2909                 $pieces[] = Html::closeElement( 'head' );
2910
2911                 $bodyClasses = $this->mAdditionalBodyClasses;
2912                 $bodyClasses[] = 'mediawiki';
2913
2914                 # Classes for LTR/RTL directionality support
2915                 $bodyClasses[] = $userdir;
2916                 $bodyClasses[] = "sitedir-$sitedir";
2917
2918                 $underline = $this->getUser()->getOption( 'underline' );
2919                 if ( $underline < 2 ) {
2920                         // The following classes can be used here:
2921                         // * mw-underline-always
2922                         // * mw-underline-never
2923                         $bodyClasses[] = 'mw-underline-' . ( $underline ? 'always' : 'never' );
2924                 }
2925
2926                 if ( $this->getLanguage()->capitalizeAllNouns() ) {
2927                         # A <body> class is probably not the best way to do this . . .
2928                         $bodyClasses[] = 'capitalize-all-nouns';
2929                 }
2930
2931                 // Parser feature migration class
2932                 // The idea is that this will eventually be removed, after the wikitext
2933                 // which requires it is cleaned up.
2934                 $bodyClasses[] = 'mw-hide-empty-elt';
2935
2936                 $bodyClasses[] = $sk->getPageClasses( $this->getTitle() );
2937                 $bodyClasses[] = 'skin-' . Sanitizer::escapeClass( $sk->getSkinName() );
2938                 $bodyClasses[] =
2939                         'action-' . Sanitizer::escapeClass( Action::getActionName( $this->getContext() ) );
2940
2941                 $bodyAttrs = [];
2942                 // While the implode() is not strictly needed, it's used for backwards compatibility
2943                 // (this used to be built as a string and hooks likely still expect that).
2944                 $bodyAttrs['class'] = implode( ' ', $bodyClasses );
2945
2946                 // Allow skins and extensions to add body attributes they need
2947                 $sk->addToBodyAttributes( $this, $bodyAttrs );
2948                 Hooks::run( 'OutputPageBodyAttributes', [ $this, $sk, &$bodyAttrs ] );
2949
2950                 $pieces[] = Html::openElement( 'body', $bodyAttrs );
2951
2952                 return self::combineWrappedStrings( $pieces );
2953         }
2954
2955         /**
2956          * Get a ResourceLoader object associated with this OutputPage
2957          *
2958          * @return ResourceLoader
2959          */
2960         public function getResourceLoader() {
2961                 if ( is_null( $this->mResourceLoader ) ) {
2962                         $this->mResourceLoader = new ResourceLoader(
2963                                 $this->getConfig(),
2964                                 LoggerFactory::getInstance( 'resourceloader' )
2965                         );
2966                 }
2967                 return $this->mResourceLoader;
2968         }
2969
2970         /**
2971          * Explicily load or embed modules on a page.
2972          *
2973          * @param array|string $modules One or more module names
2974          * @param string $only ResourceLoaderModule TYPE_ class constant
2975          * @param array $extraQuery [optional] Array with extra query parameters for the request
2976          * @return string|WrappedStringList HTML
2977          */
2978         public function makeResourceLoaderLink( $modules, $only, array $extraQuery = [] ) {
2979                 // Apply 'target' and 'origin' filters
2980                 $modules = $this->filterModules( (array)$modules, null, $only );
2981
2982                 return ResourceLoaderClientHtml::makeLoad(
2983                         $this->getRlClientContext(),
2984                         $modules,
2985                         $only,
2986                         $extraQuery,
2987                         $this->getCSPNonce()
2988                 );
2989         }
2990
2991         /**
2992          * Combine WrappedString chunks and filter out empty ones
2993          *
2994          * @param array $chunks
2995          * @return string|WrappedStringList HTML
2996          */
2997         protected static function combineWrappedStrings( array $chunks ) {
2998                 // Filter out empty values
2999                 $chunks = array_filter( $chunks, 'strlen' );
3000                 return WrappedString::join( "\n", $chunks );
3001         }
3002
3003         /**
3004          * JS stuff to put at the bottom of the `<body>`.
3005          * These are legacy scripts ($this->mScripts), and user JS.
3006          *
3007          * @return string|WrappedStringList HTML
3008          */
3009         public function getBottomScripts() {
3010                 $chunks = [];
3011                 $chunks[] = $this->getRlClient()->getBodyHtml();
3012
3013                 // Legacy non-ResourceLoader scripts
3014                 $chunks[] = $this->mScripts;
3015
3016                 if ( $this->limitReportJSData ) {
3017                         $chunks[] = ResourceLoader::makeInlineScript(
3018                                 ResourceLoader::makeConfigSetScript(
3019                                         [ 'wgPageParseReport' => $this->limitReportJSData ]
3020                                 ),
3021                                 $this->getCSPNonce()
3022                         );
3023                 }
3024
3025                 return self::combineWrappedStrings( $chunks );
3026         }
3027
3028         /**
3029          * Get the javascript config vars to include on this page
3030          *
3031          * @return array Array of javascript config vars
3032          * @since 1.23
3033          */
3034         public function getJsConfigVars() {
3035                 return $this->mJsConfigVars;
3036         }
3037
3038         /**
3039          * Add one or more variables to be set in mw.config in JavaScript
3040          *
3041          * @param string|array $keys Key or array of key/value pairs
3042          * @param mixed|null $value [optional] Value of the configuration variable
3043          */
3044         public function addJsConfigVars( $keys, $value = null ) {
3045                 if ( is_array( $keys ) ) {
3046                         foreach ( $keys as $key => $value ) {
3047                                 $this->mJsConfigVars[$key] = $value;
3048                         }
3049                         return;
3050                 }
3051
3052                 $this->mJsConfigVars[$keys] = $value;
3053         }
3054
3055         /**
3056          * Get an array containing the variables to be set in mw.config in JavaScript.
3057          *
3058          * Do not add things here which can be evaluated in ResourceLoaderStartUpModule
3059          * - in other words, page-independent/site-wide variables (without state).
3060          * You will only be adding bloat to the html page and causing page caches to
3061          * have to be purged on configuration changes.
3062          * @return array
3063          */
3064         public function getJSVars() {
3065                 global $wgContLang;
3066
3067                 $curRevisionId = 0;
3068                 $articleId = 0;
3069                 $canonicalSpecialPageName = false; # T23115
3070
3071                 $title = $this->getTitle();
3072                 $ns = $title->getNamespace();
3073                 $canonicalNamespace = MWNamespace::exists( $ns )
3074                         ? MWNamespace::getCanonicalName( $ns )
3075                         : $title->getNsText();
3076
3077                 $sk = $this->getSkin();
3078                 // Get the relevant title so that AJAX features can use the correct page name
3079                 // when making API requests from certain special pages (T36972).
3080                 $relevantTitle = $sk->getRelevantTitle();
3081                 $relevantUser = $sk->getRelevantUser();
3082
3083                 if ( $ns == NS_SPECIAL ) {
3084                         list( $canonicalSpecialPageName, /*...*/ ) =
3085                                 SpecialPageFactory::resolveAlias( $title->getDBkey() );
3086                 } elseif ( $this->canUseWikiPage() ) {
3087                         $wikiPage = $this->getWikiPage();
3088                         $curRevisionId = $wikiPage->getLatest();
3089                         $articleId = $wikiPage->getId();
3090                 }
3091
3092                 $lang = $title->getPageViewLanguage();
3093
3094                 // Pre-process information
3095                 $separatorTransTable = $lang->separatorTransformTable();
3096                 $separatorTransTable = $separatorTransTable ?: [];
3097                 $compactSeparatorTransTable = [
3098                         implode( "\t", array_keys( $separatorTransTable ) ),
3099                         implode( "\t", $separatorTransTable ),
3100                 ];
3101                 $digitTransTable = $lang->digitTransformTable();
3102                 $digitTransTable = $digitTransTable ?: [];
3103                 $compactDigitTransTable = [
3104                         implode( "\t", array_keys( $digitTransTable ) ),
3105                         implode( "\t", $digitTransTable ),
3106                 ];
3107
3108                 $user = $this->getUser();
3109
3110                 $vars = [
3111                         'wgCanonicalNamespace' => $canonicalNamespace,
3112                         'wgCanonicalSpecialPageName' => $canonicalSpecialPageName,
3113                         'wgNamespaceNumber' => $title->getNamespace(),
3114                         'wgPageName' => $title->getPrefixedDBkey(),
3115                         'wgTitle' => $title->getText(),
3116                         'wgCurRevisionId' => $curRevisionId,
3117                         'wgRevisionId' => (int)$this->getRevisionId(),
3118                         'wgArticleId' => $articleId,
3119                         'wgIsArticle' => $this->isArticle(),
3120                         'wgIsRedirect' => $title->isRedirect(),
3121                         'wgAction' => Action::getActionName( $this->getContext() ),
3122                         'wgUserName' => $user->isAnon() ? null : $user->getName(),
3123                         'wgUserGroups' => $user->getEffectiveGroups(),
3124                         'wgCategories' => $this->getCategories(),
3125                         'wgBreakFrames' => $this->getFrameOptions() == 'DENY',
3126                         'wgPageContentLanguage' => $lang->getCode(),
3127                         'wgPageContentModel' => $title->getContentModel(),
3128                         'wgSeparatorTransformTable' => $compactSeparatorTransTable,
3129                         'wgDigitTransformTable' => $compactDigitTransTable,
3130                         'wgDefaultDateFormat' => $lang->getDefaultDateFormat(),
3131                         'wgMonthNames' => $lang->getMonthNamesArray(),
3132                         'wgMonthNamesShort' => $lang->getMonthAbbreviationsArray(),
3133                         'wgRelevantPageName' => $relevantTitle->getPrefixedDBkey(),
3134                         'wgRelevantArticleId' => $relevantTitle->getArticleID(),
3135                         'wgRequestId' => WebRequest::getRequestId(),
3136                         'wgCSPNonce' => $this->getCSPNonce(),
3137                 ];
3138
3139                 if ( $user->isLoggedIn() ) {
3140                         $vars['wgUserId'] = $user->getId();
3141                         $vars['wgUserEditCount'] = $user->getEditCount();
3142                         $userReg = $user->getRegistration();
3143                         $vars['wgUserRegistration'] = $userReg ? wfTimestamp( TS_UNIX, $userReg ) * 1000 : null;
3144                         // Get the revision ID of the oldest new message on the user's talk
3145                         // page. This can be used for constructing new message alerts on
3146                         // the client side.
3147                         $vars['wgUserNewMsgRevisionId'] = $user->getNewMessageRevisionId();
3148                 }
3149
3150                 if ( $wgContLang->hasVariants() ) {
3151                         $vars['wgUserVariant'] = $wgContLang->getPreferredVariant();
3152                 }
3153                 // Same test as SkinTemplate
3154                 $vars['wgIsProbablyEditable'] = $title->quickUserCan( 'edit', $user )
3155                         && ( $title->exists() || $title->quickUserCan( 'create', $user ) );
3156
3157                 $vars['wgRelevantPageIsProbablyEditable'] = $relevantTitle
3158                         && $relevantTitle->quickUserCan( 'edit', $user )
3159                         && ( $relevantTitle->exists() || $relevantTitle->quickUserCan( 'create', $user ) );
3160
3161                 foreach ( $title->getRestrictionTypes() as $type ) {
3162                         // Following keys are set in $vars:
3163                         // wgRestrictionCreate, wgRestrictionEdit, wgRestrictionMove, wgRestrictionUpload
3164                         $vars['wgRestriction' . ucfirst( $type )] = $title->getRestrictions( $type );
3165                 }
3166
3167                 if ( $title->isMainPage() ) {
3168                         $vars['wgIsMainPage'] = true;
3169                 }
3170
3171                 if ( $this->mRedirectedFrom ) {
3172                         $vars['wgRedirectedFrom'] = $this->mRedirectedFrom->getPrefixedDBkey();
3173                 }
3174
3175                 if ( $relevantUser ) {
3176                         $vars['wgRelevantUserName'] = $relevantUser->getName();
3177                 }
3178
3179                 // Allow extensions to add their custom variables to the mw.config map.
3180                 // Use the 'ResourceLoaderGetConfigVars' hook if the variable is not
3181                 // page-dependant but site-wide (without state).
3182                 // Alternatively, you may want to use OutputPage->addJsConfigVars() instead.
3183                 Hooks::run( 'MakeGlobalVariablesScript', [ &$vars, $this ] );
3184
3185                 // Merge in variables from addJsConfigVars last
3186                 return array_merge( $vars, $this->getJsConfigVars() );
3187         }
3188
3189         /**
3190          * To make it harder for someone to slip a user a fake
3191          * JavaScript or CSS preview, a random token
3192          * is associated with the login session. If it's not
3193          * passed back with the preview request, we won't render
3194          * the code.
3195          *
3196          * @return bool
3197          */
3198         public function userCanPreview() {
3199                 $request = $this->getRequest();
3200                 if (
3201                         $request->getVal( 'action' ) !== 'submit' ||
3202                         !$request->wasPosted()
3203                 ) {
3204                         return false;
3205                 }
3206
3207                 $user = $this->getUser();
3208
3209                 if ( !$user->isLoggedIn() ) {
3210                         // Anons have predictable edit tokens
3211                         return false;
3212                 }
3213                 if ( !$user->matchEditToken( $request->getVal( 'wpEditToken' ) ) ) {
3214                         return false;
3215                 }
3216
3217                 $title = $this->getTitle();
3218                 $errors = $title->getUserPermissionsErrors( 'edit', $user );
3219                 if ( count( $errors ) !== 0 ) {
3220                         return false;
3221                 }
3222
3223                 return true;
3224         }
3225
3226         /**
3227          * @return array Array in format "link name or number => 'link html'".
3228          */
3229         public function getHeadLinksArray() {
3230                 global $wgVersion;
3231
3232                 $tags = [];
3233                 $config = $this->getConfig();
3234
3235                 $canonicalUrl = $this->mCanonicalUrl;
3236
3237                 $tags['meta-generator'] = Html::element( 'meta', [
3238                         'name' => 'generator',
3239                         'content' => "MediaWiki $wgVersion",
3240                 ] );
3241
3242                 if ( $config->get( 'ReferrerPolicy' ) !== false ) {
3243                         // Per https://w3c.github.io/webappsec-referrer-policy/#unknown-policy-values
3244                         // fallbacks should come before the primary value so we need to reverse the array.
3245                         foreach ( array_reverse( (array)$config->get( 'ReferrerPolicy' ) ) as $i => $policy ) {
3246                                 $tags["meta-referrer-$i"] = Html::element( 'meta', [
3247                                         'name' => 'referrer',
3248                                         'content' => $policy,
3249                                 ] );
3250                         }
3251                 }
3252
3253                 $p = "{$this->mIndexPolicy},{$this->mFollowPolicy}";
3254                 if ( $p !== 'index,follow' ) {
3255                         // http://www.robotstxt.org/wc/meta-user.html
3256                         // Only show if it's different from the default robots policy
3257                         $tags['meta-robots'] = Html::element( 'meta', [
3258                                 'name' => 'robots',
3259                                 'content' => $p,
3260                         ] );
3261                 }
3262
3263                 foreach ( $this->mMetatags as $tag ) {
3264                         if ( strncasecmp( $tag[0], 'http:', 5 ) === 0 ) {
3265                                 $a = 'http-equiv';
3266                                 $tag[0] = substr( $tag[0], 5 );
3267                         } elseif ( strncasecmp( $tag[0], 'og:', 3 ) === 0 ) {
3268                                 $a = 'property';
3269                         } else {
3270                                 $a = 'name';
3271                         }
3272                         $tagName = "meta-{$tag[0]}";
3273                         if ( isset( $tags[$tagName] ) ) {
3274                                 $tagName .= $tag[1];
3275                         }
3276                         $tags[$tagName] = Html::element( 'meta',
3277                                 [
3278                                         $a => $tag[0],
3279                                         'content' => $tag[1]
3280                                 ]
3281                         );
3282                 }
3283
3284                 foreach ( $this->mLinktags as $tag ) {
3285                         $tags[] = Html::element( 'link', $tag );
3286                 }
3287
3288                 # Universal edit button
3289                 if ( $config->get( 'UniversalEditButton' ) && $this->isArticleRelated() ) {
3290                         $user = $this->getUser();
3291                         if ( $this->getTitle()->quickUserCan( 'edit', $user )
3292                                 && ( $this->getTitle()->exists() ||
3293                                         $this->getTitle()->quickUserCan( 'create', $user ) )
3294                         ) {
3295                                 // Original UniversalEditButton
3296                                 $msg = $this->msg( 'edit' )->text();
3297                                 $tags['universal-edit-button'] = Html::element( 'link', [
3298                                         'rel' => 'alternate',
3299                                         'type' => 'application/x-wiki',
3300                                         'title' => $msg,
3301                                         'href' => $this->getTitle()->getEditURL(),
3302                                 ] );
3303                                 // Alternate edit link
3304                                 $tags['alternative-edit'] = Html::element( 'link', [
3305                                         'rel' => 'edit',
3306                                         'title' => $msg,
3307                                         'href' => $this->getTitle()->getEditURL(),
3308                                 ] );
3309                         }
3310                 }
3311
3312                 # Generally the order of the favicon and apple-touch-icon links
3313                 # should not matter, but Konqueror (3.5.9 at least) incorrectly
3314                 # uses whichever one appears later in the HTML source. Make sure
3315                 # apple-touch-icon is specified first to avoid this.
3316                 if ( $config->get( 'AppleTouchIcon' ) !== false ) {
3317                         $tags['apple-touch-icon'] = Html::element( 'link', [
3318                                 'rel' => 'apple-touch-icon',
3319                                 'href' => $config->get( 'AppleTouchIcon' )
3320                         ] );
3321                 }
3322
3323                 if ( $config->get( 'Favicon' ) !== false ) {
3324                         $tags['favicon'] = Html::element( 'link', [
3325                                 'rel' => 'shortcut icon',
3326                                 'href' => $config->get( 'Favicon' )
3327                         ] );
3328                 }
3329
3330                 # OpenSearch description link
3331                 $tags['opensearch'] = Html::element( 'link', [
3332                         'rel' => 'search',
3333                         'type' => 'application/opensearchdescription+xml',
3334                         'href' => wfScript( 'opensearch_desc' ),
3335                         'title' => $this->msg( 'opensearch-desc' )->inContentLanguage()->text(),
3336                 ] );
3337
3338                 # Real Simple Discovery link, provides auto-discovery information
3339                 # for the MediaWiki API (and potentially additional custom API
3340                 # support such as WordPress or Twitter-compatible APIs for a
3341                 # blogging extension, etc)
3342                 $tags['rsd'] = Html::element( 'link', [
3343                         'rel' => 'EditURI',
3344                         'type' => 'application/rsd+xml',
3345                         // Output a protocol-relative URL here if $wgServer is protocol-relative.
3346                         // Whether RSD accepts relative or protocol-relative URLs is completely
3347                         // undocumented, though.
3348                         'href' => wfExpandUrl( wfAppendQuery(
3349                                 wfScript( 'api' ),
3350                                 [ 'action' => 'rsd' ] ),
3351                                 PROTO_RELATIVE
3352                         ),
3353                 ] );
3354
3355                 # Language variants
3356                 if ( !$config->get( 'DisableLangConversion' ) ) {
3357                         $lang = $this->getTitle()->getPageLanguage();
3358                         if ( $lang->hasVariants() ) {
3359                                 $variants = $lang->getVariants();
3360                                 foreach ( $variants as $variant ) {
3361                                         $tags["variant-$variant"] = Html::element( 'link', [
3362                                                 'rel' => 'alternate',
3363                                                 'hreflang' => LanguageCode::bcp47( $variant ),
3364                                                 'href' => $this->getTitle()->getLocalURL(
3365                                                         [ 'variant' => $variant ] )
3366                                                 ]
3367                                         );
3368                                 }
3369                                 # x-default link per https://support.google.com/webmasters/answer/189077?hl=en
3370                                 $tags["variant-x-default"] = Html::element( 'link', [
3371                                         'rel' => 'alternate',
3372                                         'hreflang' => 'x-default',
3373                                         'href' => $this->getTitle()->getLocalURL() ] );
3374                         }
3375                 }
3376
3377                 # Copyright
3378                 if ( $this->copyrightUrl !== null ) {
3379                         $copyright = $this->copyrightUrl;
3380                 } else {
3381                         $copyright = '';
3382                         if ( $config->get( 'RightsPage' ) ) {
3383                                 $copy = Title::newFromText( $config->get( 'RightsPage' ) );
3384
3385                                 if ( $copy ) {
3386                                         $copyright = $copy->getLocalURL();
3387                                 }
3388                         }
3389
3390                         if ( !$copyright && $config->get( 'RightsUrl' ) ) {
3391                                 $copyright = $config->get( 'RightsUrl' );
3392                         }
3393                 }
3394
3395                 if ( $copyright ) {
3396                         $tags['copyright'] = Html::element( 'link', [
3397                                 'rel' => 'license',
3398                                 'href' => $copyright ]
3399                         );
3400                 }
3401
3402                 # Feeds
3403                 if ( $config->get( 'Feed' ) ) {
3404                         $feedLinks = [];
3405
3406                         foreach ( $this->getSyndicationLinks() as $format => $link ) {
3407                                 # Use the page name for the title.  In principle, this could
3408                                 # lead to issues with having the same name for different feeds
3409                                 # corresponding to the same page, but we can't avoid that at
3410                                 # this low a level.
3411
3412                                 $feedLinks[] = $this->feedLink(
3413                                         $format,
3414                                         $link,
3415                                         # Used messages: 'page-rss-feed' and 'page-atom-feed' (for an easier grep)
3416                                         $this->msg(
3417                                                 "page-{$format}-feed", $this->getTitle()->getPrefixedText()
3418                                         )->text()
3419                                 );
3420                         }
3421
3422                         # Recent changes feed should appear on every page (except recentchanges,
3423                         # that would be redundant). Put it after the per-page feed to avoid
3424                         # changing existing behavior. It's still available, probably via a
3425                         # menu in your browser. Some sites might have a different feed they'd
3426                         # like to promote instead of the RC feed (maybe like a "Recent New Articles"
3427                         # or "Breaking news" one). For this, we see if $wgOverrideSiteFeed is defined.
3428                         # If so, use it instead.
3429                         $sitename = $config->get( 'Sitename' );
3430                         if ( $config->get( 'OverrideSiteFeed' ) ) {
3431                                 foreach ( $config->get( 'OverrideSiteFeed' ) as $type => $feedUrl ) {
3432                                         // Note, this->feedLink escapes the url.
3433                                         $feedLinks[] = $this->feedLink(
3434                                                 $type,
3435                                                 $feedUrl,
3436                                                 $this->msg( "site-{$type}-feed", $sitename )->text()
3437                                         );
3438                                 }
3439                         } elseif ( !$this->getTitle()->isSpecial( 'Recentchanges' ) ) {
3440                                 $rctitle = SpecialPage::getTitleFor( 'Recentchanges' );
3441                                 foreach ( $config->get( 'AdvertisedFeedTypes' ) as $format ) {
3442                                         $feedLinks[] = $this->feedLink(
3443                                                 $format,
3444                                                 $rctitle->getLocalURL( [ 'feed' => $format ] ),
3445                                                 # For grep: 'site-rss-feed', 'site-atom-feed'
3446                                                 $this->msg( "site-{$format}-feed", $sitename )->text()
3447                                         );
3448                                 }
3449                         }
3450
3451                         # Allow extensions to change the list pf feeds. This hook is primarily for changing,
3452                         # manipulating or removing existing feed tags. If you want to add new feeds, you should
3453                         # use OutputPage::addFeedLink() instead.
3454                         Hooks::run( 'AfterBuildFeedLinks', [ &$feedLinks ] );
3455
3456                         $tags += $feedLinks;
3457                 }
3458
3459                 # Canonical URL
3460                 if ( $config->get( 'EnableCanonicalServerLink' ) ) {
3461                         if ( $canonicalUrl !== false ) {
3462                                 $canonicalUrl = wfExpandUrl( $canonicalUrl, PROTO_CANONICAL );
3463                         } else {
3464                                 if ( $this->isArticleRelated() ) {
3465                                         // This affects all requests where "setArticleRelated" is true. This is
3466                                         // typically all requests that show content (query title, curid, oldid, diff),
3467                                         // and all wikipage actions (edit, delete, purge, info, history etc.).
3468                                         // It does not apply to File pages and Special pages.
3469                                         // 'history' and 'info' actions address page metadata rather than the page
3470                                         // content itself, so they may not be canonicalized to the view page url.
3471                                         // TODO: this ought to be better encapsulated in the Action class.
3472                                         $action = Action::getActionName( $this->getContext() );
3473                                         if ( in_array( $action, [ 'history', 'info' ] ) ) {
3474                                                 $query = "action={$action}";
3475                                         } else {
3476                                                 $query = '';
3477                                         }
3478                                         $canonicalUrl = $this->getTitle()->getCanonicalURL( $query );
3479                                 } else {
3480                                         $reqUrl = $this->getRequest()->getRequestURL();
3481                                         $canonicalUrl = wfExpandUrl( $reqUrl, PROTO_CANONICAL );
3482                                 }
3483                         }
3484                 }
3485                 if ( $canonicalUrl !== false ) {
3486                         $tags[] = Html::element( 'link', [
3487                                 'rel' => 'canonical',
3488                                 'href' => $canonicalUrl
3489                         ] );
3490                 }
3491
3492                 // Allow extensions to add, remove and/or otherwise manipulate these links
3493                 // If you want only to *add* <head> links, please use the addHeadItem()
3494                 // (or addHeadItems() for multiple items) method instead.
3495                 // This hook is provided as a last resort for extensions to modify these
3496                 // links before the output is sent to client.
3497                 Hooks::run( 'OutputPageAfterGetHeadLinksArray', [ &$tags, $this ] );
3498
3499                 return $tags;
3500         }
3501
3502         /**
3503          * Generate a "<link rel/>" for a feed.
3504          *
3505          * @param string $type Feed type
3506          * @param string $url URL to the feed
3507          * @param string $text Value of the "title" attribute
3508          * @return string HTML fragment
3509          */
3510         private function feedLink( $type, $url, $text ) {
3511                 return Html::element( 'link', [
3512                         'rel' => 'alternate',
3513                         'type' => "application/$type+xml",
3514                         'title' => $text,
3515                         'href' => $url ]
3516                 );
3517         }
3518
3519         /**
3520          * Add a local or specified stylesheet, with the given media options.
3521          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3522          *
3523          * @param string $style URL to the file
3524          * @param string $media To specify a media type, 'screen', 'printable', 'handheld' or any.
3525          * @param string $condition For IE conditional comments, specifying an IE version
3526          * @param string $dir Set to 'rtl' or 'ltr' for direction-specific sheets
3527          */
3528         public function addStyle( $style, $media = '', $condition = '', $dir = '' ) {
3529                 $options = [];
3530                 if ( $media ) {
3531                         $options['media'] = $media;
3532                 }
3533                 if ( $condition ) {
3534                         $options['condition'] = $condition;
3535                 }
3536                 if ( $dir ) {
3537                         $options['dir'] = $dir;
3538                 }
3539                 $this->styles[$style] = $options;
3540         }
3541
3542         /**
3543          * Adds inline CSS styles
3544          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3545          *
3546          * @param mixed $style_css Inline CSS
3547          * @param string $flip Set to 'flip' to flip the CSS if needed
3548          */
3549         public function addInlineStyle( $style_css, $flip = 'noflip' ) {
3550                 if ( $flip === 'flip' && $this->getLanguage()->isRTL() ) {
3551                         # If wanted, and the interface is right-to-left, flip the CSS
3552                         $style_css = CSSJanus::transform( $style_css, true, false );
3553                 }
3554                 $this->mInlineStyles .= Html::inlineStyle( $style_css );
3555         }
3556
3557         /**
3558          * Build exempt modules and legacy non-ResourceLoader styles.
3559          *
3560          * @return string|WrappedStringList HTML
3561          */
3562         protected function buildExemptModules() {
3563                 $chunks = [];
3564                 // Things that go after the ResourceLoaderDynamicStyles marker
3565                 $append = [];
3566
3567                 // We want site, private and user styles to override dynamically added styles from
3568                 // general modules, but we want dynamically added styles to override statically added
3569                 // style modules. So the order has to be:
3570                 // - page style modules (formatted by ResourceLoaderClientHtml::getHeadHtml())
3571                 // - dynamically loaded styles (added by mw.loader before ResourceLoaderDynamicStyles)
3572                 // - ResourceLoaderDynamicStyles marker
3573                 // - site/private/user styles
3574
3575                 // Add legacy styles added through addStyle()/addInlineStyle() here
3576                 $chunks[] = implode( '', $this->buildCssLinksArray() ) . $this->mInlineStyles;
3577
3578                 $chunks[] = Html::element(
3579                         'meta',
3580                         [ 'name' => 'ResourceLoaderDynamicStyles', 'content' => '' ]
3581                 );
3582
3583                 $separateReq = [ 'site.styles', 'user.styles' ];
3584                 foreach ( $this->rlExemptStyleModules as $group => $moduleNames ) {
3585                         // Combinable modules
3586                         $chunks[] = $this->makeResourceLoaderLink(
3587                                 array_diff( $moduleNames, $separateReq ),
3588                                 ResourceLoaderModule::TYPE_STYLES
3589                         );
3590
3591                         foreach ( array_intersect( $moduleNames, $separateReq ) as $name ) {
3592                                 // These require their own dedicated request in order to support "@import"
3593                                 // syntax, which is incompatible with concatenation. (T147667, T37562)
3594                                 $chunks[] = $this->makeResourceLoaderLink( $name,
3595                                         ResourceLoaderModule::TYPE_STYLES
3596                                 );
3597                         }
3598                 }
3599
3600                 return self::combineWrappedStrings( array_merge( $chunks, $append ) );
3601         }
3602
3603         /**
3604          * @return array
3605          */
3606         public function buildCssLinksArray() {
3607                 $links = [];
3608
3609                 foreach ( $this->styles as $file => $options ) {
3610                         $link = $this->styleLink( $file, $options );
3611                         if ( $link ) {
3612                                 $links[$file] = $link;
3613                         }
3614                 }
3615                 return $links;
3616         }
3617
3618         /**
3619          * Generate \<link\> tags for stylesheets
3620          *
3621          * @param string $style URL to the file
3622          * @param array $options Option, can contain 'condition', 'dir', 'media' keys
3623          * @return string HTML fragment
3624          */
3625         protected function styleLink( $style, array $options ) {
3626                 if ( isset( $options['dir'] ) ) {
3627                         if ( $this->getLanguage()->getDir() != $options['dir'] ) {
3628                                 return '';
3629                         }
3630                 }
3631
3632                 if ( isset( $options['media'] ) ) {
3633                         $media = self::transformCssMedia( $options['media'] );
3634                         if ( is_null( $media ) ) {
3635                                 return '';
3636                         }
3637                 } else {
3638                         $media = 'all';
3639                 }
3640
3641                 if ( substr( $style, 0, 1 ) == '/' ||
3642                         substr( $style, 0, 5 ) == 'http:' ||
3643                         substr( $style, 0, 6 ) == 'https:' ) {
3644                         $url = $style;
3645                 } else {
3646                         $config = $this->getConfig();
3647                         // Append file hash as query parameter
3648                         $url = self::transformResourcePath(
3649                                 $config,
3650                                 $config->get( 'StylePath' ) . '/' . $style
3651                         );
3652                 }
3653
3654                 $link = Html::linkedStyle( $url, $media );
3655
3656                 if ( isset( $options['condition'] ) ) {
3657                         $condition = htmlspecialchars( $options['condition'] );
3658                         $link = "<!--[if $condition]>$link<![endif]-->";
3659                 }
3660                 return $link;
3661         }
3662
3663         /**
3664          * Transform path to web-accessible static resource.
3665          *
3666          * This is used to add a validation hash as query string.
3667          * This aids various behaviors:
3668          *
3669          * - Put long Cache-Control max-age headers on responses for improved
3670          *   cache performance.
3671          * - Get the correct version of a file as expected by the current page.
3672          * - Instantly get the updated version of a file after deployment.
3673          *
3674          * Avoid using this for urls included in HTML as otherwise clients may get different
3675          * versions of a resource when navigating the site depending on when the page was cached.
3676          * If changes to the url propagate, this is not a problem (e.g. if the url is in
3677          * an external stylesheet).
3678          *
3679          * @since 1.27
3680          * @param Config $config
3681          * @param string $path Path-absolute URL to file (from document root, must start with "/")
3682          * @return string URL
3683          */
3684         public static function transformResourcePath( Config $config, $path ) {
3685                 global $IP;
3686
3687                 $localDir = $IP;
3688                 $remotePathPrefix = $config->get( 'ResourceBasePath' );
3689                 if ( $remotePathPrefix === '' ) {
3690                         // The configured base path is required to be empty string for
3691                         // wikis in the domain root
3692                         $remotePath = '/';
3693                 } else {
3694                         $remotePath = $remotePathPrefix;
3695                 }
3696                 if ( strpos( $path, $remotePath ) !== 0 || substr( $path, 0, 2 ) === '//' ) {
3697                         // - Path is outside wgResourceBasePath, ignore.
3698                         // - Path is protocol-relative. Fixes T155310. Not supported by RelPath lib.
3699                         return $path;
3700                 }
3701                 // For files in resources, extensions/ or skins/, ResourceBasePath is preferred here.
3702                 // For other misc files in $IP, we'll fallback to that as well. There is, however, a fourth
3703                 // supported dir/path pair in the configuration (wgUploadDirectory, wgUploadPath)
3704                 // which is not expected to be in wgResourceBasePath on CDNs. (T155146)
3705                 $uploadPath = $config->get( 'UploadPath' );
3706                 if ( strpos( $path, $uploadPath ) === 0 ) {
3707                         $localDir = $config->get( 'UploadDirectory' );
3708                         $remotePathPrefix = $remotePath = $uploadPath;
3709                 }
3710
3711                 $path = RelPath::getRelativePath( $path, $remotePath );
3712                 return self::transformFilePath( $remotePathPrefix, $localDir, $path );
3713         }
3714
3715         /**
3716          * Utility method for transformResourceFilePath().
3717          *
3718          * Caller is responsible for ensuring the file exists. Emits a PHP warning otherwise.
3719          *
3720          * @since 1.27
3721          * @param string $remotePathPrefix URL path prefix that points to $localPath
3722          * @param string $localPath File directory exposed at $remotePath
3723          * @param string $file Path to target file relative to $localPath
3724          * @return string URL
3725          */
3726         public static function transformFilePath( $remotePathPrefix, $localPath, $file ) {
3727                 $hash = md5_file( "$localPath/$file" );
3728                 if ( $hash === false ) {
3729                         wfLogWarning( __METHOD__ . ": Failed to hash $localPath/$file" );
3730                         $hash = '';
3731                 }
3732                 return "$remotePathPrefix/$file?" . substr( $hash, 0, 5 );
3733         }
3734
3735         /**
3736          * Transform "media" attribute based on request parameters
3737          *
3738          * @param string $media Current value of the "media" attribute
3739          * @return string Modified value of the "media" attribute, or null to skip
3740          * this stylesheet
3741          */
3742         public static function transformCssMedia( $media ) {
3743                 global $wgRequest;
3744
3745                 // https://www.w3.org/TR/css3-mediaqueries/#syntax
3746                 $screenMediaQueryRegex = '/^(?:only\s+)?screen\b/i';
3747
3748                 // Switch in on-screen display for media testing
3749                 $switches = [
3750                         'printable' => 'print',
3751                         'handheld' => 'handheld',
3752                 ];
3753                 foreach ( $switches as $switch => $targetMedia ) {
3754                         if ( $wgRequest->getBool( $switch ) ) {
3755                                 if ( $media == $targetMedia ) {
3756                                         $media = '';
3757                                 } elseif ( preg_match( $screenMediaQueryRegex, $media ) === 1 ) {
3758                                         /* This regex will not attempt to understand a comma-separated media_query_list
3759                                          *
3760                                          * Example supported values for $media:
3761                                          * 'screen', 'only screen', 'screen and (min-width: 982px)' ),
3762                                          * Example NOT supported value for $media:
3763                                          * '3d-glasses, screen, print and resolution > 90dpi'
3764                                          *
3765                                          * If it's a print request, we never want any kind of screen stylesheets
3766                                          * If it's a handheld request (currently the only other choice with a switch),
3767                                          * we don't want simple 'screen' but we might want screen queries that
3768                                          * have a max-width or something, so we'll pass all others on and let the
3769                                          * client do the query.
3770                                          */
3771                                         if ( $targetMedia == 'print' || $media == 'screen' ) {
3772                                                 return null;
3773                                         }
3774                                 }
3775                         }
3776                 }
3777
3778                 return $media;
3779         }
3780
3781         /**
3782          * Add a wikitext-formatted message to the output.
3783          * This is equivalent to:
3784          *
3785          *    $wgOut->addWikiText( wfMessage( ... )->plain() )
3786          */
3787         public function addWikiMsg( /*...*/ ) {
3788                 $args = func_get_args();
3789                 $name = array_shift( $args );
3790                 $this->addWikiMsgArray( $name, $args );
3791         }
3792
3793         /**
3794          * Add a wikitext-formatted message to the output.
3795          * Like addWikiMsg() except the parameters are taken as an array
3796          * instead of a variable argument list.
3797          *
3798          * @param string $name
3799          * @param array $args
3800          */
3801         public function addWikiMsgArray( $name, $args ) {
3802                 $this->addHTML( $this->msg( $name, $args )->parseAsBlock() );
3803         }
3804
3805         /**
3806          * This function takes a number of message/argument specifications, wraps them in
3807          * some overall structure, and then parses the result and adds it to the output.
3808          *
3809          * In the $wrap, $1 is replaced with the first message, $2 with the second,
3810          * and so on. The subsequent arguments may be either
3811          * 1) strings, in which case they are message names, or
3812          * 2) arrays, in which case, within each array, the first element is the message
3813          *    name, and subsequent elements are the parameters to that message.
3814          *
3815          * Don't use this for messages that are not in the user's interface language.
3816          *
3817          * For example:
3818          *
3819          *    $wgOut->wrapWikiMsg( "<div class='error'>\n$1\n</div>", 'some-error' );
3820          *
3821          * Is equivalent to:
3822          *
3823          *    $wgOut->addWikiText( "<div class='error'>\n"
3824          *        . wfMessage( 'some-error' )->plain() . "\n</div>" );
3825          *
3826          * The newline after the opening div is needed in some wikitext. See T21226.
3827          *
3828          * @param string $wrap
3829          */
3830         public function wrapWikiMsg( $wrap /*, ...*/ ) {
3831                 $msgSpecs = func_get_args();
3832                 array_shift( $msgSpecs );
3833                 $msgSpecs = array_values( $msgSpecs );
3834                 $s = $wrap;
3835                 foreach ( $msgSpecs as $n => $spec ) {
3836                         if ( is_array( $spec ) ) {
3837                                 $args = $spec;
3838                                 $name = array_shift( $args );
3839                                 if ( isset( $args['options'] ) ) {
3840                                         unset( $args['options'] );
3841                                         wfDeprecated(
3842                                                 'Adding "options" to ' . __METHOD__ . ' is no longer supported',
3843                                                 '1.20'
3844                                         );
3845                                 }
3846                         } else {
3847                                 $args = [];
3848                                 $name = $spec;
3849                         }
3850                         $s = str_replace( '$' . ( $n + 1 ), $this->msg( $name, $args )->plain(), $s );
3851                 }
3852                 $this->addWikiText( $s );
3853         }
3854
3855         /**
3856          * Whether the output has a table of contents
3857          * @return bool
3858          * @since 1.22
3859          */
3860         public function isTOCEnabled() {
3861                 return $this->mEnableTOC;
3862         }
3863
3864         /**
3865          * Enables/disables section edit links, doesn't override __NOEDITSECTION__
3866          * @param bool $flag
3867          * @since 1.23
3868          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
3869          */
3870         public function enableSectionEditLinks( $flag = true ) {
3871                 wfDeprecated( __METHOD__, '1.31' );
3872         }
3873
3874         /**
3875          * @return bool
3876          * @since 1.23
3877          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
3878          */
3879         public function sectionEditLinksEnabled() {
3880                 wfDeprecated( __METHOD__, '1.31' );
3881                 return true;
3882         }
3883
3884         /**
3885          * Helper function to setup the PHP implementation of OOUI to use in this request.
3886          *
3887          * @since 1.26
3888          * @param String $skinName The Skin name to determine the correct OOUI theme
3889          * @param String $dir Language direction
3890          */
3891         public static function setupOOUI( $skinName = 'default', $dir = 'ltr' ) {
3892                 $themes = ResourceLoaderOOUIModule::getSkinThemeMap();
3893                 $theme = $themes[$skinName] ?? $themes['default'];
3894                 // For example, 'OOUI\WikimediaUITheme'.
3895                 $themeClass = "OOUI\\{$theme}Theme";
3896                 OOUI\Theme::setSingleton( new $themeClass() );
3897                 OOUI\Element::setDefaultDir( $dir );
3898         }
3899
3900         /**
3901          * Add ResourceLoader module styles for OOUI and set up the PHP implementation of it for use with
3902          * MediaWiki and this OutputPage instance.
3903          *
3904          * @since 1.25
3905          */
3906         public function enableOOUI() {
3907                 self::setupOOUI(
3908                         strtolower( $this->getSkin()->getSkinName() ),
3909                         $this->getLanguage()->getDir()
3910                 );
3911                 $this->addModuleStyles( [
3912                         'oojs-ui-core.styles',
3913                         'oojs-ui.styles.indicators',
3914                         'oojs-ui.styles.textures',
3915                         'mediawiki.widgets.styles',
3916                         'oojs-ui.styles.icons-content',
3917                         'oojs-ui.styles.icons-alerts',
3918                         'oojs-ui.styles.icons-interactions',
3919                 ] );
3920         }
3921
3922         /**
3923          * Add Link headers for preloading the wiki's logo.
3924          *
3925          * @since 1.26
3926          */
3927         protected function addLogoPreloadLinkHeaders() {
3928                 $logo = ResourceLoaderSkinModule::getLogo( $this->getConfig() );
3929
3930                 $tags = [];
3931                 $logosPerDppx = [];
3932                 $logos = [];
3933
3934                 if ( !is_array( $logo ) ) {
3935                         // No media queries required if we only have one variant
3936                         $this->addLinkHeader( '<' . $logo . '>;rel=preload;as=image' );
3937                         return;
3938                 }
3939
3940                 if ( isset( $logo['svg'] ) ) {
3941                         // No media queries required if we only have a 1x and svg variant
3942                         // because all preload-capable browsers support SVGs
3943                         $this->addLinkHeader( '<' . $logo['svg'] . '>;rel=preload;as=image' );
3944                         return;
3945                 }
3946
3947                 foreach ( $logo as $dppx => $src ) {
3948                         // Keys are in this format: "1.5x"
3949                         $dppx = substr( $dppx, 0, -1 );
3950                         $logosPerDppx[$dppx] = $src;
3951                 }
3952
3953                 // Because PHP can't have floats as array keys
3954                 uksort( $logosPerDppx, function ( $a , $b ) {
3955                         $a = floatval( $a );
3956                         $b = floatval( $b );
3957                         // Sort from smallest to largest (e.g. 1x, 1.5x, 2x)
3958                         return $a <=> $b;
3959                 } );
3960
3961                 foreach ( $logosPerDppx as $dppx => $src ) {
3962                         $logos[] = [ 'dppx' => $dppx, 'src' => $src ];
3963                 }
3964
3965                 $logosCount = count( $logos );
3966                 // Logic must match ResourceLoaderSkinModule:
3967                 // - 1x applies to resolution < 1.5dppx
3968                 // - 1.5x applies to resolution >= 1.5dppx && < 2dppx
3969                 // - 2x applies to resolution >= 2dppx
3970                 // Note that min-resolution and max-resolution are both inclusive.
3971                 for ( $i = 0; $i < $logosCount; $i++ ) {
3972                         if ( $i === 0 ) {
3973                                 // Smallest dppx
3974                                 // min-resolution is ">=" (larger than or equal to)
3975                                 // "not min-resolution" is essentially "<"
3976                                 $media_query = 'not all and (min-resolution: ' . $logos[ 1 ]['dppx'] . 'dppx)';
3977                         } elseif ( $i !== $logosCount - 1 ) {
3978                                 // In between
3979                                 // Media query expressions can only apply "not" to the entire expression
3980                                 // (e.g. can't express ">= 1.5 and not >= 2).
3981                                 // Workaround: Use <= 1.9999 in place of < 2.
3982                                 $upper_bound = floatval( $logos[ $i + 1 ]['dppx'] ) - 0.000001;
3983                                 $media_query = '(min-resolution: ' . $logos[ $i ]['dppx'] .
3984                                         'dppx) and (max-resolution: ' . $upper_bound . 'dppx)';
3985                         } else {
3986                                 // Largest dppx
3987                                 $media_query = '(min-resolution: ' . $logos[ $i ]['dppx'] . 'dppx)';
3988                         }
3989
3990                         $this->addLinkHeader(
3991                                 '<' . $logos[$i]['src'] . '>;rel=preload;as=image;media=' . $media_query
3992                         );
3993                 }
3994         }
3995
3996         /**
3997          * Get (and set if not yet set) the CSP nonce.
3998          *
3999          * This value needs to be included in any <script> tags on the
4000          * page.
4001          *
4002          * @return string|bool Nonce or false to mean don't output nonce
4003          * @since 1.32
4004          */
4005         public function getCSPNonce() {
4006                 if ( !ContentSecurityPolicy::isNonceRequired( $this->getConfig() ) ) {
4007                         return false;
4008                 }
4009                 if ( $this->CSPNonce === null ) {
4010                         // XXX It might be expensive to generate randomness
4011                         // on every request, on Windows.
4012                         $rand = random_bytes( 15 );
4013                         $this->CSPNonce = base64_encode( $rand );
4014                 }
4015                 return $this->CSPNonce;
4016         }
4017 }