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\MediaWikiServices;
  25 use MediaWiki\Session\SessionManager;
  26 use Wikimedia\Rdbms\IResultWrapper;
  27 use Wikimedia\RelPath;
  28 use Wikimedia\WrappedString;
  29 use Wikimedia\WrappedStringList;
  30
  31 /**
  32  * This class should be covered by a general architecture document which does
  33  * not exist as of January 2011.  This is one of the Core classes and should
  34  * be read at least once by any new developers.
  35  *
  36  * This class is used to prepare the final rendering. A skin is then
  37  * applied to the output parameters (links, javascript, html, categories ...).
  38  *
  39  * @todo FIXME: Another class handles sending the whole page to the client.
  40  *
  41  * Some comments comes from a pairing session between Zak Greant and Antoine Musso
  42  * in November 2010.
  43  *
  44  * @todo document
  45  */
  46 class OutputPage extends ContextSource {
  47         /** @var array Should be private. Used with addMeta() which adds "<meta>" */
  48         protected $mMetatags = [];
  49
  50         /** @var array */
  51         protected $mLinktags = [];
  52
  53         /** @var bool */
  54         protected $mCanonicalUrl = false;
  55
  56         /**
  57          * @var string The contents of <h1> */
  58         private $mPageTitle = '';
  59
  60         /**
  61          * @var string The displayed title of the page. Different from page title
  62          * if overridden by display title magic word or hooks. Can contain safe
  63          * HTML. Different from page title which may contain messages such as
  64          * "Editing X" which is displayed in h1. This can be used for other places
  65          * where the page name is referred on the page.
  66          */
  67         private $displayTitle;
  68
  69         /**
  70          * @var string Contains all of the "<body>" content. Should be private we
  71          *   got set/get accessors and the append() method.
  72          */
  73         public $mBodytext = '';
  74
  75         /** @var string Stores contents of "<title>" tag */
  76         private $mHTMLtitle = '';
  77
  78         /**
  79          * @var bool Is the displayed content related to the source of the
  80          *   corresponding wiki article.
  81          */
  82         private $mIsArticle = false;
  83
  84         /** @var bool Stores "article flag" toggle. */
  85         private $mIsArticleRelated = true;
  86
  87         /** @var bool Is the content subject to copyright */
  88         private $mHasCopyright = false;
  89
  90         /**
  91          * @var bool We have to set isPrintable(). Some pages should
  92          * never be printed (ex: redirections).
  93          */
  94         private $mPrintable = false;
  95
  96         /**
  97          * @var array Contains the page subtitle. Special pages usually have some
  98          *   links here. Don't confuse with site subtitle added by skins.
  99          */
 100         private $mSubtitle = [];
 101
 102         /** @var string */
 103         public $mRedirect = '';
 104
 105         /** @var int */
 106         protected $mStatusCode;
 107
 108         /**
 109          * @var string Used for sending cache control.
 110          *   The whole caching system should probably be moved into its own class.
 111          */
 112         protected $mLastModified = '';
 113
 114         /** @var array */
 115         protected $mCategoryLinks = [];
 116
 117         /** @var array */
 118         protected $mCategories = [
 119                 'hidden' => [],
 120                 'normal' => [],
 121         ];
 122
 123         /** @var array */
 124         protected $mIndicators = [];
 125
 126         /** @var array Array of Interwiki Prefixed (non DB key) Titles (e.g. 'fr:Test page') */
 127         private $mLanguageLinks = [];
 128
 129         /**
 130          * Used for JavaScript (predates ResourceLoader)
 131          * @todo We should split JS / CSS.
 132          * mScripts content is inserted as is in "<head>" by Skin. This might
 133          * contain either a link to a stylesheet or inline CSS.
 134          */
 135         private $mScripts = '';
 136
 137         /** @var string Inline CSS styles. Use addInlineStyle() sparingly */
 138         protected $mInlineStyles = '';
 139
 140         /**
 141          * @var string Used by skin template.
 142          * Example: $tpl->set( 'displaytitle', $out->mPageLinkTitle );
 143          */
 144         public $mPageLinkTitle = '';
 145
 146         /** @var array Array of elements in "<head>". Parser might add its own headers! */
 147         protected $mHeadItems = [];
 148
 149         /** @var array Additional <body> classes; there are also <body> classes from other sources */
 150         protected $mAdditionalBodyClasses = [];
 151
 152         /** @var array */
 153         protected $mModules = [];
 154
 155         /** @var array */
 156         protected $mModuleStyles = [];
 157
 158         /** @var ResourceLoader */
 159         protected $mResourceLoader;
 160
 161         /** @var ResourceLoaderClientHtml */
 162         private $rlClient;
 163
 164         /** @var ResourceLoaderContext */
 165         private $rlClientContext;
 166
 167         /** @var array */
 168         private $rlExemptStyleModules;
 169
 170         /** @var array */
 171         protected $mJsConfigVars = [];
 172
 173         /** @var array */
 174         protected $mTemplateIds = [];
 175
 176         /** @var array */
 177         protected $mImageTimeKeys = [];
 178
 179         /** @var string */
 180         public $mRedirectCode = '';
 181
 182         protected $mFeedLinksAppendQuery = null;
 183
 184         /** @var array
 185          * What level of 'untrustworthiness' is allowed in CSS/JS modules loaded on this page?
 186          * @see ResourceLoaderModule::$origin
 187          * ResourceLoaderModule::ORIGIN_ALL is assumed unless overridden;
 188          */
 189         protected $mAllowedModules = [
 190                 ResourceLoaderModule::TYPE_COMBINED => ResourceLoaderModule::ORIGIN_ALL,
 191         ];
 192
 193         /** @var bool Whether output is disabled.  If this is true, the 'output' method will do nothing. */
 194         protected $mDoNothing = false;
 195
 196         // Parser related.
 197
 198         /** @var int */
 199         protected $mContainsNewMagic = 0;
 200
 201         /**
 202          * lazy initialised, use parserOptions()
 203          * @var ParserOptions
 204          */
 205         protected $mParserOptions = null;
 206
 207         /**
 208          * Handles the Atom / RSS links.
 209          * We probably only support Atom in 2011.
 210          * @see $wgAdvertisedFeedTypes
 211          */
 212         private $mFeedLinks = [];
 213
 214         // Gwicke work on squid caching? Roughly from 2003.
 215         protected $mEnableClientCache = true;
 216
 217         /** @var bool Flag if output should only contain the body of the article. */
 218         private $mArticleBodyOnly = false;
 219
 220         /** @var bool */
 221         protected $mNewSectionLink = false;
 222
 223         /** @var bool */
 224         protected $mHideNewSectionLink = false;
 225
 226         /**
 227          * @var bool Comes from the parser. This was probably made to load CSS/JS
 228          * only if we had "<gallery>". Used directly in CategoryPage.php.
 229          * Looks like ResourceLoader can replace this.
 230          */
 231         public $mNoGallery = false;
 232
 233         /** @var int Cache stuff. Looks like mEnableClientCache */
 234         protected $mCdnMaxage = 0;
 235         /** @var int Upper limit on mCdnMaxage */
 236         protected $mCdnMaxageLimit = INF;
 237
 238         /**
 239          * @var bool Controls if anti-clickjacking / frame-breaking headers will
 240          * be sent. This should be done for pages where edit actions are possible.
 241          * Setters: $this->preventClickjacking() and $this->allowClickjacking().
 242          */
 243         protected $mPreventClickjacking = true;
 244
 245         /** @var int To include the variable {{REVISIONID}} */
 246         private $mRevisionId = null;
 247
 248         /** @var string */
 249         private $mRevisionTimestamp = null;
 250
 251         /** @var array */
 252         protected $mFileVersion = null;
 253
 254         /**
 255          * @var array An array of stylesheet filenames (relative from skins path),
 256          * with options for CSS media, IE conditions, and RTL/LTR direction.
 257          * For internal use; add settings in the skin via $this->addStyle()
 258          *
 259          * Style again! This seems like a code duplication since we already have
 260          * mStyles. This is what makes Open Source amazing.
 261          */
 262         protected $styles = [];
 263
 264         private $mIndexPolicy = 'index';
 265         private $mFollowPolicy = 'follow';
 266
 267         /**
 268          * @var array Headers that cause the cache to vary.  Key is header name, value is an array of
 269          * options for the Key header.
 270          */
 271         private $mVaryHeader = [
 272                 'Accept-Encoding' => [ 'match=gzip' ],
 273         ];
 274
 275         /**
 276          * If the current page was reached through a redirect, $mRedirectedFrom contains the Title
 277          * of the redirect.
 278          *
 279          * @var Title
 280          */
 281         private $mRedirectedFrom = null;
 282
 283         /**
 284          * Additional key => value data
 285          */
 286         private $mProperties = [];
 287
 288         /**
 289          * @var string|null ResourceLoader target for load.php links. If null, will be omitted
 290          */
 291         private $mTarget = null;
 292
 293         /**
 294          * @var bool Whether parser output contains a table of contents
 295          */
 296         private $mEnableTOC = false;
 297
 298         /**
 299          * @var string|null The URL to send in a <link> element with rel=license
 300          */
 301         private $copyrightUrl;
 302
 303         /** @var array Profiling data */
 304         private $limitReportJSData = [];
 305
 306         /** @var array Map Title to Content */
 307         private $contentOverrides = [];
 308
 309         /** @var callable[] */
 310         private $contentOverrideCallbacks = [];
 311
 312         /**
 313          * Link: header contents
 314          */
 315         private $mLinkHeader = [];
 316
 317         /**
 318          * @var string The nonce for Content-Security-Policy
 319          */
 320         private $CSPNonce;
 321
 322         /**
 323          * @var array A cache of the names of the cookies that will influence the cache
 324          */
 325         private static $cacheVaryCookies = null;
 326
 327         /**
 328          * Constructor for OutputPage. This should not be called directly.
 329          * Instead a new RequestContext should be created and it will implicitly create
 330          * a OutputPage tied to that context.
 331          * @param IContextSource $context
 332          */
 333         function __construct( IContextSource $context ) {
 334                 $this->setContext( $context );
 335         }
 336
 337         /**
 338          * Redirect to $url rather than displaying the normal page
 339          *
 340          * @param string $url
 341          * @param string $responsecode HTTP status code
 342          */
 343         public function redirect( $url, $responsecode = '302' ) {
 344                 # Strip newlines as a paranoia check for header injection in PHP<5.1.2
 345                 $this->mRedirect = str_replace( "\n", '', $url );
 346                 $this->mRedirectCode = $responsecode;
 347         }
 348
 349         /**
 350          * Get the URL to redirect to, or an empty string if not redirect URL set
 351          *
 352          * @return string
 353          */
 354         public function getRedirect() {
 355                 return $this->mRedirect;
 356         }
 357
 358         /**
 359          * Set the copyright URL to send with the output.
 360          * Empty string to omit, null to reset.
 361          *
 362          * @since 1.26
 363          *
 364          * @param string|null $url
 365          */
 366         public function setCopyrightUrl( $url ) {
 367                 $this->copyrightUrl = $url;
 368         }
 369
 370         /**
 371          * Set the HTTP status code to send with the output.
 372          *
 373          * @param int $statusCode
 374          */
 375         public function setStatusCode( $statusCode ) {
 376                 $this->mStatusCode = $statusCode;
 377         }
 378
 379         /**
 380          * Add a new "<meta>" tag
 381          * To add an http-equiv meta tag, precede the name with "http:"
 382          *
 383          * @param string $name Name of the meta tag
 384          * @param string $val Value of the meta tag
 385          */
 386         function addMeta( $name, $val ) {
 387                 array_push( $this->mMetatags, [ $name, $val ] );
 388         }
 389
 390         /**
 391          * Returns the current <meta> tags
 392          *
 393          * @since 1.25
 394          * @return array
 395          */
 396         public function getMetaTags() {
 397                 return $this->mMetatags;
 398         }
 399
 400         /**
 401          * Add a new \<link\> tag to the page header.
 402          *
 403          * Note: use setCanonicalUrl() for rel=canonical.
 404          *
 405          * @param array $linkarr Associative array of attributes.
 406          */
 407         function addLink( array $linkarr ) {
 408                 array_push( $this->mLinktags, $linkarr );
 409         }
 410
 411         /**
 412          * Returns the current <link> tags
 413          *
 414          * @since 1.25
 415          * @return array
 416          */
 417         public function getLinkTags() {
 418                 return $this->mLinktags;
 419         }
 420
 421         /**
 422          * Set the URL to be used for the <link rel=canonical>. This should be used
 423          * in preference to addLink(), to avoid duplicate link tags.
 424          * @param string $url
 425          */
 426         function setCanonicalUrl( $url ) {
 427                 $this->mCanonicalUrl = $url;
 428         }
 429
 430         /**
 431          * Returns the URL to be used for the <link rel=canonical> if
 432          * one is set.
 433          *
 434          * @since 1.25
 435          * @return bool|string
 436          */
 437         public function getCanonicalUrl() {
 438                 return $this->mCanonicalUrl;
 439         }
 440
 441         /**
 442          * Add raw HTML to the list of scripts (including \<script\> tag, etc.)
 443          * Internal use only. Use OutputPage::addModules() or OutputPage::addJsConfigVars()
 444          * if possible.
 445          *
 446          * @param string $script Raw HTML
 447          */
 448         function addScript( $script ) {
 449                 $this->mScripts .= $script;
 450         }
 451
 452         /**
 453          * Add a JavaScript file to be loaded as `<script>` on this page.
 454          *
 455          * Internal use only. Use OutputPage::addModules() if possible.
 456          *
 457          * @param string $file URL to file (absolute path, protocol-relative, or full url)
 458          * @param string|null $unused Previously used to change the cache-busting query parameter
 459          */
 460         public function addScriptFile( $file, $unused = null ) {
 461                 if ( substr( $file, 0, 1 ) !== '/' && !preg_match( '#^[a-z]*://#i', $file ) ) {
 462                         // This is not an absolute path, protocol-relative url, or full scheme url,
 463                         // presumed to be an old call intended to include a file from /w/skins/common,
 464                         // which doesn't exist anymore as of MediaWiki 1.24 per T71277. Ignore.
 465                         wfDeprecated( __METHOD__, '1.24' );
 466                         return;
 467                 }
 468                 $this->addScript( Html::linkedScript( $file, $this->getCSPNonce() ) );
 469         }
 470
 471         /**
 472          * Add a self-contained script tag with the given contents
 473          * Internal use only. Use OutputPage::addModules() if possible.
 474          *
 475          * @param string $script JavaScript text, no script tags
 476          */
 477         public function addInlineScript( $script ) {
 478                 $this->mScripts .= Html::inlineScript( "\n$script\n", $this->getCSPNonce() ) . "\n";
 479         }
 480
 481         /**
 482          * Filter an array of modules to remove insufficiently trustworthy members, and modules
 483          * which are no longer registered (eg a page is cached before an extension is disabled)
 484          * @param array $modules
 485          * @param string|null $position Unused
 486          * @param string $type
 487          * @return array
 488          */
 489         protected function filterModules( array $modules, $position = null,
 490                 $type = ResourceLoaderModule::TYPE_COMBINED
 491         ) {
 492                 $resourceLoader = $this->getResourceLoader();
 493                 $filteredModules = [];
 494                 foreach ( $modules as $val ) {
 495                         $module = $resourceLoader->getModule( $val );
 496                         if ( $module instanceof ResourceLoaderModule
 497                                 && $module->getOrigin() <= $this->getAllowedModules( $type )
 498                         ) {
 499                                 if ( $this->mTarget && !in_array( $this->mTarget, $module->getTargets() ) ) {
 500                                         $this->warnModuleTargetFilter( $module->getName() );
 501                                         continue;
 502                                 }
 503                                 $filteredModules[] = $val;
 504                         }
 505                 }
 506                 return $filteredModules;
 507         }
 508
 509         private function warnModuleTargetFilter( $moduleName ) {
 510                 static $warnings = [];
 511                 if ( isset( $warnings[$this->mTarget][$moduleName] ) ) {
 512                         return;
 513                 }
 514                 $warnings[$this->mTarget][$moduleName] = true;
 515                 $this->getResourceLoader()->getLogger()->debug(
 516                         'Module "{module}" not loadable on target "{target}".',
 517                         [
 518                                 'module' => $moduleName,
 519                                 'target' => $this->mTarget,
 520                         ]
 521                 );
 522         }
 523
 524         /**
 525          * Get the list of modules to include on this page
 526          *
 527          * @param bool $filter Whether to filter out insufficiently trustworthy modules
 528          * @param string|null $position Unused
 529          * @param string $param
 530          * @param string $type
 531          * @return array Array of module names
 532          */
 533         public function getModules( $filter = false, $position = null, $param = 'mModules',
 534                 $type = ResourceLoaderModule::TYPE_COMBINED
 535         ) {
 536                 $modules = array_values( array_unique( $this->$param ) );
 537                 return $filter
 538                         ? $this->filterModules( $modules, null, $type )
 539                         : $modules;
 540         }
 541
 542         /**
 543          * Load one or more ResourceLoader modules on this page.
 544          *
 545          * @param string|array $modules Module name (string) or array of module names
 546          */
 547         public function addModules( $modules ) {
 548                 $this->mModules = array_merge( $this->mModules, (array)$modules );
 549         }
 550
 551         /**
 552          * @deprecated since 1.33 Use getModules() instead.
 553          * @return array
 554          */
 555         public function getModuleScripts() {
 556                 wfDeprecated( __METHOD__, '1.33' );
 557                 return [];
 558         }
 559
 560         /**
 561          * Get the list of style-only modules to load on this page.
 562          *
 563          * @param bool $filter
 564          * @param string|null $position Unused
 565          * @return array Array of module names
 566          */
 567         public function getModuleStyles( $filter = false, $position = null ) {
 568                 return $this->getModules( $filter, null, 'mModuleStyles',
 569                         ResourceLoaderModule::TYPE_STYLES
 570                 );
 571         }
 572
 573         /**
 574          * Load the styles of one or more ResourceLoader modules on this page.
 575          *
 576          * Module styles added through this function will be loaded as a stylesheet,
 577          * using a standard `<link rel=stylesheet>` HTML tag, rather than as a combined
 578          * Javascript and CSS package. Thus, they will even load when JavaScript is disabled.
 579          *
 580          * @param string|array $modules Module name (string) or array of module names
 581          */
 582         public function addModuleStyles( $modules ) {
 583                 $this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
 584         }
 585
 586         /**
 587          * @return null|string ResourceLoader target
 588          */
 589         public function getTarget() {
 590                 return $this->mTarget;
 591         }
 592
 593         /**
 594          * Sets ResourceLoader target for load.php links. If null, will be omitted
 595          *
 596          * @param string|null $target
 597          */
 598         public function setTarget( $target ) {
 599                 $this->mTarget = $target;
 600         }
 601
 602         /**
 603          * Add a mapping from a LinkTarget to a Content, for things like page preview.
 604          * @see self::addContentOverrideCallback()
 605          * @since 1.32
 606          * @param LinkTarget $target
 607          * @param Content $content
 608          */
 609         public function addContentOverride( LinkTarget $target, Content $content ) {
 610                 if ( !$this->contentOverrides ) {
 611                         // Register a callback for $this->contentOverrides on the first call
 612                         $this->addContentOverrideCallback( function ( LinkTarget $target ) {
 613                                 $key = $target->getNamespace() . ':' . $target->getDBkey();
 614                                 return $this->contentOverrides[$key] ?? null;
 615                         } );
 616                 }
 617
 618                 $key = $target->getNamespace() . ':' . $target->getDBkey();
 619                 $this->contentOverrides[$key] = $content;
 620         }
 621
 622         /**
 623          * Add a callback for mapping from a Title to a Content object, for things
 624          * like page preview.
 625          * @see ResourceLoaderContext::getContentOverrideCallback()
 626          * @since 1.32
 627          * @param callable $callback
 628          */
 629         public function addContentOverrideCallback( callable $callback ) {
 630                 $this->contentOverrideCallbacks[] = $callback;
 631         }
 632
 633         /**
 634          * Get an array of head items
 635          *
 636          * @return array
 637          */
 638         function getHeadItemsArray() {
 639                 return $this->mHeadItems;
 640         }
 641
 642         /**
 643          * Add or replace a head item to the output
 644          *
 645          * Whenever possible, use more specific options like ResourceLoader modules,
 646          * OutputPage::addLink(), OutputPage::addMetaLink() and OutputPage::addFeedLink()
 647          * Fallback options for those are: OutputPage::addStyle, OutputPage::addScript(),
 648          * OutputPage::addInlineScript() and OutputPage::addInlineStyle()
 649          * This would be your very LAST fallback.
 650          *
 651          * @param string $name Item name
 652          * @param string $value Raw HTML
 653          */
 654         public function addHeadItem( $name, $value ) {
 655                 $this->mHeadItems[$name] = $value;
 656         }
 657
 658         /**
 659          * Add one or more head items to the output
 660          *
 661          * @since 1.28
 662          * @param string|string[] $values Raw HTML
 663          */
 664         public function addHeadItems( $values ) {
 665                 $this->mHeadItems = array_merge( $this->mHeadItems, (array)$values );
 666         }
 667
 668         /**
 669          * Check if the header item $name is already set
 670          *
 671          * @param string $name Item name
 672          * @return bool
 673          */
 674         public function hasHeadItem( $name ) {
 675                 return isset( $this->mHeadItems[$name] );
 676         }
 677
 678         /**
 679          * Add a class to the <body> element
 680          *
 681          * @since 1.30
 682          * @param string|string[] $classes One or more classes to add
 683          */
 684         public function addBodyClasses( $classes ) {
 685                 $this->mAdditionalBodyClasses = array_merge( $this->mAdditionalBodyClasses, (array)$classes );
 686         }
 687
 688         /**
 689          * Set whether the output should only contain the body of the article,
 690          * without any skin, sidebar, etc.
 691          * Used e.g. when calling with "action=render".
 692          *
 693          * @param bool $only Whether to output only the body of the article
 694          */
 695         public function setArticleBodyOnly( $only ) {
 696                 $this->mArticleBodyOnly = $only;
 697         }
 698
 699         /**
 700          * Return whether the output will contain only the body of the article
 701          *
 702          * @return bool
 703          */
 704         public function getArticleBodyOnly() {
 705                 return $this->mArticleBodyOnly;
 706         }
 707
 708         /**
 709          * Set an additional output property
 710          * @since 1.21
 711          *
 712          * @param string $name
 713          * @param mixed $value
 714          */
 715         public function setProperty( $name, $value ) {
 716                 $this->mProperties[$name] = $value;
 717         }
 718
 719         /**
 720          * Get an additional output property
 721          * @since 1.21
 722          *
 723          * @param string $name
 724          * @return mixed Property value or null if not found
 725          */
 726         public function getProperty( $name ) {
 727                 return $this->mProperties[$name] ?? null;
 728         }
 729
 730         /**
 731          * checkLastModified tells the client to use the client-cached page if
 732          * possible. If successful, the OutputPage is disabled so that
 733          * any future call to OutputPage->output() have no effect.
 734          *
 735          * Side effect: sets mLastModified for Last-Modified header
 736          *
 737          * @param string $timestamp
 738          *
 739          * @return bool True if cache-ok headers was sent.
 740          */
 741         public function checkLastModified( $timestamp ) {
 742                 if ( !$timestamp || $timestamp == '19700101000000' ) {
 743                         wfDebug( __METHOD__ . ": CACHE DISABLED, NO TIMESTAMP\n" );
 744                         return false;
 745                 }
 746                 $config = $this->getConfig();
 747                 if ( !$config->get( 'CachePages' ) ) {
 748                         wfDebug( __METHOD__ . ": CACHE DISABLED\n" );
 749                         return false;
 750                 }
 751
 752                 $timestamp = wfTimestamp( TS_MW, $timestamp );
 753                 $modifiedTimes = [
 754                         'page' => $timestamp,
 755                         'user' => $this->getUser()->getTouched(),
 756                         'epoch' => $config->get( 'CacheEpoch' )
 757                 ];
 758                 if ( $config->get( 'UseSquid' ) ) {
 759                         $modifiedTimes['sepoch'] = wfTimestamp( TS_MW, $this->getCdnCacheEpoch(
 760                                 time(),
 761                                 $config->get( 'SquidMaxage' )
 762                         ) );
 763                 }
 764                 Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this ] );
 765
 766                 $maxModified = max( $modifiedTimes );
 767                 $this->mLastModified = wfTimestamp( TS_RFC2822, $maxModified );
 768
 769                 $clientHeader = $this->getRequest()->getHeader( 'If-Modified-Since' );
 770                 if ( $clientHeader === false ) {
 771                         wfDebug( __METHOD__ . ": client did not send If-Modified-Since header", 'private' );
 772                         return false;
 773                 }
 774
 775                 # IE sends sizes after the date like this:
 776                 # Wed, 20 Aug 2003 06:51:19 GMT; length=5202
 777                 # this breaks strtotime().
 778                 $clientHeader = preg_replace( '/;.*$/', '', $clientHeader );
 779
 780                 Wikimedia\suppressWarnings(); // E_STRICT system time warnings
 781                 $clientHeaderTime = strtotime( $clientHeader );
 782                 Wikimedia\restoreWarnings();
 783                 if ( !$clientHeaderTime ) {
 784                         wfDebug( __METHOD__
 785                                 . ": unable to parse the client's If-Modified-Since header: $clientHeader\n" );
 786                         return false;
 787                 }
 788                 $clientHeaderTime = wfTimestamp( TS_MW, $clientHeaderTime );
 789
 790                 # Make debug info
 791                 $info = '';
 792                 foreach ( $modifiedTimes as $name => $value ) {
 793                         if ( $info !== '' ) {
 794                                 $info .= ', ';
 795                         }
 796                         $info .= "$name=" . wfTimestamp( TS_ISO_8601, $value );
 797                 }
 798
 799                 wfDebug( __METHOD__ . ": client sent If-Modified-Since: " .
 800                         wfTimestamp( TS_ISO_8601, $clientHeaderTime ), 'private' );
 801                 wfDebug( __METHOD__ . ": effective Last-Modified: " .
 802                         wfTimestamp( TS_ISO_8601, $maxModified ), 'private' );
 803                 if ( $clientHeaderTime < $maxModified ) {
 804                         wfDebug( __METHOD__ . ": STALE, $info", 'private' );
 805                         return false;
 806                 }
 807
 808                 # Not modified
 809                 # Give a 304 Not Modified response code and disable body output
 810                 wfDebug( __METHOD__ . ": NOT MODIFIED, $info", 'private' );
 811                 ini_set( 'zlib.output_compression', 0 );
 812                 $this->getRequest()->response()->statusHeader( 304 );
 813                 $this->sendCacheControl();
 814                 $this->disable();
 815
 816                 // Don't output a compressed blob when using ob_gzhandler;
 817                 // it's technically against HTTP spec and seems to confuse
 818                 // Firefox when the response gets split over two packets.
 819                 wfClearOutputBuffers();
 820
 821                 return true;
 822         }
 823
 824         /**
 825          * @param int $reqTime Time of request (eg. now)
 826          * @param int $maxAge Cache TTL in seconds
 827          * @return int Timestamp
 828          */
 829         private function getCdnCacheEpoch( $reqTime, $maxAge ) {
 830                 // Ensure Last-Modified is never more than (wgSquidMaxage) in the past,
 831                 // because even if the wiki page content hasn't changed since, static
 832                 // resources may have changed (skin HTML, interface messages, urls, etc.)
 833                 // and must roll-over in a timely manner (T46570)
 834                 return $reqTime - $maxAge;
 835         }
 836
 837         /**
 838          * Override the last modified timestamp
 839          *
 840          * @param string $timestamp New timestamp, in a format readable by
 841          *        wfTimestamp()
 842          */
 843         public function setLastModified( $timestamp ) {
 844                 $this->mLastModified = wfTimestamp( TS_RFC2822, $timestamp );
 845         }
 846
 847         /**
 848          * Set the robot policy for the page: <http://www.robotstxt.org/meta.html>
 849          *
 850          * @param string $policy The literal string to output as the contents of
 851          *   the meta tag.  Will be parsed according to the spec and output in
 852          *   standardized form.
 853          * @return null
 854          */
 855         public function setRobotPolicy( $policy ) {
 856                 $policy = Article::formatRobotPolicy( $policy );
 857
 858                 if ( isset( $policy['index'] ) ) {
 859                         $this->setIndexPolicy( $policy['index'] );
 860                 }
 861                 if ( isset( $policy['follow'] ) ) {
 862                         $this->setFollowPolicy( $policy['follow'] );
 863                 }
 864         }
 865
 866         /**
 867          * Set the index policy for the page, but leave the follow policy un-
 868          * touched.
 869          *
 870          * @param string $policy Either 'index' or 'noindex'.
 871          * @return null
 872          */
 873         public function setIndexPolicy( $policy ) {
 874                 $policy = trim( $policy );
 875                 if ( in_array( $policy, [ 'index', 'noindex' ] ) ) {
 876                         $this->mIndexPolicy = $policy;
 877                 }
 878         }
 879
 880         /**
 881          * Set the follow policy for the page, but leave the index policy un-
 882          * touched.
 883          *
 884          * @param string $policy Either 'follow' or 'nofollow'.
 885          * @return null
 886          */
 887         public function setFollowPolicy( $policy ) {
 888                 $policy = trim( $policy );
 889                 if ( in_array( $policy, [ 'follow', 'nofollow' ] ) ) {
 890                         $this->mFollowPolicy = $policy;
 891                 }
 892         }
 893
 894         /**
 895          * "HTML title" means the contents of "<title>".
 896          * It is stored as plain, unescaped text and will be run through htmlspecialchars in the skin file.
 897          *
 898          * @param string|Message $name
 899          */
 900         public function setHTMLTitle( $name ) {
 901                 if ( $name instanceof Message ) {
 902                         $this->mHTMLtitle = $name->setContext( $this->getContext() )->text();
 903                 } else {
 904                         $this->mHTMLtitle = $name;
 905                 }
 906         }
 907
 908         /**
 909          * Return the "HTML title", i.e. the content of the "<title>" tag.
 910          *
 911          * @return string
 912          */
 913         public function getHTMLTitle() {
 914                 return $this->mHTMLtitle;
 915         }
 916
 917         /**
 918          * Set $mRedirectedFrom, the Title of the page which redirected us to the current page.
 919          *
 920          * @param Title $t
 921          */
 922         public function setRedirectedFrom( $t ) {
 923                 $this->mRedirectedFrom = $t;
 924         }
 925
 926         /**
 927          * "Page title" means the contents of \<h1\>. It is stored as a valid HTML
 928          * fragment. This function allows good tags like \<sup\> in the \<h1\> tag,
 929          * but not bad tags like \<script\>. This function automatically sets
 930          * \<title\> to the same content as \<h1\> but with all tags removed. Bad
 931          * tags that were escaped in \<h1\> will still be escaped in \<title\>, and
 932          * good tags like \<i\> will be dropped entirely.
 933          *
 934          * @param string|Message $name
 935          * @param-taint $name tainted
 936          * Phan-taint-check gets very confused by $name being either a string or a Message
 937          */
 938         public function setPageTitle( $name ) {
 939                 if ( $name instanceof Message ) {
 940                         $name = $name->setContext( $this->getContext() )->text();
 941                 }
 942
 943                 # change "<script>foo&bar</script>" to "&lt;script&gt;foo&amp;bar&lt;/script&gt;"
 944                 # but leave "<i>foobar</i>" alone
 945                 $nameWithTags = Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $name ) );
 946                 $this->mPageTitle = $nameWithTags;
 947
 948                 # change "<i>foo&amp;bar</i>" to "foo&bar"
 949                 $this->setHTMLTitle(
 950                         $this->msg( 'pagetitle' )->plaintextParams( Sanitizer::stripAllTags( $nameWithTags ) )
 951                                 ->inContentLanguage()
 952                 );
 953         }
 954
 955         /**
 956          * Return the "page title", i.e. the content of the \<h1\> tag.
 957          *
 958          * @return string
 959          */
 960         public function getPageTitle() {
 961                 return $this->mPageTitle;
 962         }
 963
 964         /**
 965          * Same as page title but only contains name of the page, not any other text.
 966          *
 967          * @since 1.32
 968          * @param string $html Page title text.
 969          * @see OutputPage::setPageTitle
 970          */
 971         public function setDisplayTitle( $html ) {
 972                 $this->displayTitle = $html;
 973         }
 974
 975         /**
 976          * Returns page display title.
 977          *
 978          * Performs some normalization, but this not as strict the magic word.
 979          *
 980          * @since 1.32
 981          * @return string HTML
 982          */
 983         public function getDisplayTitle() {
 984                 $html = $this->displayTitle;
 985                 if ( $html === null ) {
 986                         $html = $this->getTitle()->getPrefixedText();
 987                 }
 988
 989                 return Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $html ) );
 990         }
 991
 992         /**
 993          * Returns page display title without namespace prefix if possible.
 994          *
 995          * @since 1.32
 996          * @return string HTML
 997          */
 998         public function getUnprefixedDisplayTitle() {
 999                 $text = $this->getDisplayTitle();
1000                 $nsPrefix = $this->getTitle()->getNsText() . ':';
1001                 $prefix = preg_quote( $nsPrefix, '/' );
1002
1003                 return preg_replace( "/^$prefix/i", '', $text );
1004         }
1005
1006         /**
1007          * Set the Title object to use
1008          *
1009          * @param Title $t
1010          */
1011         public function setTitle( Title $t ) {
1012                 $this->getContext()->setTitle( $t );
1013         }
1014
1015         /**
1016          * Replace the subtitle with $str
1017          *
1018          * @param string|Message $str New value of the subtitle. String should be safe HTML.
1019          */
1020         public function setSubtitle( $str ) {
1021                 $this->clearSubtitle();
1022                 $this->addSubtitle( $str );
1023         }
1024
1025         /**
1026          * Add $str to the subtitle
1027          *
1028          * @param string|Message $str String or Message to add to the subtitle. String should be safe HTML.
1029          */
1030         public function addSubtitle( $str ) {
1031                 if ( $str instanceof Message ) {
1032                         $this->mSubtitle[] = $str->setContext( $this->getContext() )->parse();
1033                 } else {
1034                         $this->mSubtitle[] = $str;
1035                 }
1036         }
1037
1038         /**
1039          * Build message object for a subtitle containing a backlink to a page
1040          *
1041          * @param Title $title Title to link to
1042          * @param array $query Array of additional parameters to include in the link
1043          * @return Message
1044          * @since 1.25
1045          */
1046         public static function buildBacklinkSubtitle( Title $title, $query = [] ) {
1047                 if ( $title->isRedirect() ) {
1048                         $query['redirect'] = 'no';
1049                 }
1050                 $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1051                 return wfMessage( 'backlinksubtitle' )
1052                         ->rawParams( $linkRenderer->makeLink( $title, null, [], $query ) );
1053         }
1054
1055         /**
1056          * Add a subtitle containing a backlink to a page
1057          *
1058          * @param Title $title Title to link to
1059          * @param array $query Array of additional parameters to include in the link
1060          */
1061         public function addBacklinkSubtitle( Title $title, $query = [] ) {
1062                 $this->addSubtitle( self::buildBacklinkSubtitle( $title, $query ) );
1063         }
1064
1065         /**
1066          * Clear the subtitles
1067          */
1068         public function clearSubtitle() {
1069                 $this->mSubtitle = [];
1070         }
1071
1072         /**
1073          * Get the subtitle
1074          *
1075          * @return string
1076          */
1077         public function getSubtitle() {
1078                 return implode( "<br />\n\t\t\t\t", $this->mSubtitle );
1079         }
1080
1081         /**
1082          * Set the page as printable, i.e. it'll be displayed with all
1083          * print styles included
1084          */
1085         public function setPrintable() {
1086                 $this->mPrintable = true;
1087         }
1088
1089         /**
1090          * Return whether the page is "printable"
1091          *
1092          * @return bool
1093          */
1094         public function isPrintable() {
1095                 return $this->mPrintable;
1096         }
1097
1098         /**
1099          * Disable output completely, i.e. calling output() will have no effect
1100          */
1101         public function disable() {
1102                 $this->mDoNothing = true;
1103         }
1104
1105         /**
1106          * Return whether the output will be completely disabled
1107          *
1108          * @return bool
1109          */
1110         public function isDisabled() {
1111                 return $this->mDoNothing;
1112         }
1113
1114         /**
1115          * Show an "add new section" link?
1116          *
1117          * @return bool
1118          */
1119         public function showNewSectionLink() {
1120                 return $this->mNewSectionLink;
1121         }
1122
1123         /**
1124          * Forcibly hide the new section link?
1125          *
1126          * @return bool
1127          */
1128         public function forceHideNewSectionLink() {
1129                 return $this->mHideNewSectionLink;
1130         }
1131
1132         /**
1133          * Add or remove feed links in the page header
1134          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1135          * for the new version
1136          * @see addFeedLink()
1137          *
1138          * @param bool $show True: add default feeds, false: remove all feeds
1139          */
1140         public function setSyndicated( $show = true ) {
1141                 if ( $show ) {
1142                         $this->setFeedAppendQuery( false );
1143                 } else {
1144                         $this->mFeedLinks = [];
1145                 }
1146         }
1147
1148         /**
1149          * Return effective list of advertised feed types
1150          * @see addFeedLink()
1151          *
1152          * @return array Array of feed type names ( 'rss', 'atom' )
1153          */
1154         protected function getAdvertisedFeedTypes() {
1155                 if ( $this->getConfig()->get( 'Feed' ) ) {
1156                         return $this->getConfig()->get( 'AdvertisedFeedTypes' );
1157                 } else {
1158                         return [];
1159                 }
1160         }
1161
1162         /**
1163          * Add default feeds to the page header
1164          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1165          * for the new version
1166          * @see addFeedLink()
1167          *
1168          * @param string $val Query to append to feed links or false to output
1169          *        default links
1170          */
1171         public function setFeedAppendQuery( $val ) {
1172                 $this->mFeedLinks = [];
1173
1174                 foreach ( $this->getAdvertisedFeedTypes() as $type ) {
1175                         $query = "feed=$type";
1176                         if ( is_string( $val ) ) {
1177                                 $query .= '&' . $val;
1178                         }
1179                         $this->mFeedLinks[$type] = $this->getTitle()->getLocalURL( $query );
1180                 }
1181         }
1182
1183         /**
1184          * Add a feed link to the page header
1185          *
1186          * @param string $format Feed type, should be a key of $wgFeedClasses
1187          * @param string $href URL
1188          */
1189         public function addFeedLink( $format, $href ) {
1190                 if ( in_array( $format, $this->getAdvertisedFeedTypes() ) ) {
1191                         $this->mFeedLinks[$format] = $href;
1192                 }
1193         }
1194
1195         /**
1196          * Should we output feed links for this page?
1197          * @return bool
1198          */
1199         public function isSyndicated() {
1200                 return count( $this->mFeedLinks ) > 0;
1201         }
1202
1203         /**
1204          * Return URLs for each supported syndication format for this page.
1205          * @return array Associating format keys with URLs
1206          */
1207         public function getSyndicationLinks() {
1208                 return $this->mFeedLinks;
1209         }
1210
1211         /**
1212          * Will currently always return null
1213          *
1214          * @return null
1215          */
1216         public function getFeedAppendQuery() {
1217                 return $this->mFeedLinksAppendQuery;
1218         }
1219
1220         /**
1221          * Set whether the displayed content is related to the source of the
1222          * corresponding article on the wiki
1223          * Setting true will cause the change "article related" toggle to true
1224          *
1225          * @param bool $newVal
1226          */
1227         public function setArticleFlag( $newVal ) {
1228                 $this->mIsArticle = $newVal;
1229                 if ( $newVal ) {
1230                         $this->mIsArticleRelated = $newVal;
1231                 }
1232         }
1233
1234         /**
1235          * Return whether the content displayed page is related to the source of
1236          * the corresponding article on the wiki
1237          *
1238          * @return bool
1239          */
1240         public function isArticle() {
1241                 return $this->mIsArticle;
1242         }
1243
1244         /**
1245          * Set whether this page is related an article on the wiki
1246          * Setting false will cause the change of "article flag" toggle to false
1247          *
1248          * @param bool $newVal
1249          */
1250         public function setArticleRelated( $newVal ) {
1251                 $this->mIsArticleRelated = $newVal;
1252                 if ( !$newVal ) {
1253                         $this->mIsArticle = false;
1254                 }
1255         }
1256
1257         /**
1258          * Return whether this page is related an article on the wiki
1259          *
1260          * @return bool
1261          */
1262         public function isArticleRelated() {
1263                 return $this->mIsArticleRelated;
1264         }
1265
1266         /**
1267          * Set whether the standard copyright should be shown for the current page.
1268          *
1269          * @param bool $hasCopyright
1270          */
1271         public function setCopyright( $hasCopyright ) {
1272                 $this->mHasCopyright = $hasCopyright;
1273         }
1274
1275         /**
1276          * Return whether the standard copyright should be shown for the current page.
1277          * By default, it is true for all articles but other pages
1278          * can signal it by using setCopyright( true ).
1279          *
1280          * Used by SkinTemplate to decided whether to show the copyright.
1281          *
1282          * @return bool
1283          */
1284         public function showsCopyright() {
1285                 return $this->isArticle() || $this->mHasCopyright;
1286         }
1287
1288         /**
1289          * Add new language links
1290          *
1291          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1292          *                               (e.g. 'fr:Test page')
1293          */
1294         public function addLanguageLinks( array $newLinkArray ) {
1295                 $this->mLanguageLinks = array_merge( $this->mLanguageLinks, $newLinkArray );
1296         }
1297
1298         /**
1299          * Reset the language links and add new language links
1300          *
1301          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1302          *                               (e.g. 'fr:Test page')
1303          */
1304         public function setLanguageLinks( array $newLinkArray ) {
1305                 $this->mLanguageLinks = $newLinkArray;
1306         }
1307
1308         /**
1309          * Get the list of language links
1310          *
1311          * @return string[] Array of interwiki-prefixed (non DB key) titles (e.g. 'fr:Test page')
1312          */
1313         public function getLanguageLinks() {
1314                 return $this->mLanguageLinks;
1315         }
1316
1317         /**
1318          * Add an array of categories, with names in the keys
1319          *
1320          * @param array $categories Mapping category name => sort key
1321          */
1322         public function addCategoryLinks( array $categories ) {
1323                 if ( !$categories ) {
1324                         return;
1325                 }
1326
1327                 $res = $this->addCategoryLinksToLBAndGetResult( $categories );
1328
1329                 # Set all the values to 'normal'.
1330                 $categories = array_fill_keys( array_keys( $categories ), 'normal' );
1331
1332                 # Mark hidden categories
1333                 foreach ( $res as $row ) {
1334                         if ( isset( $row->pp_value ) ) {
1335                                 $categories[$row->page_title] = 'hidden';
1336                         }
1337                 }
1338
1339                 // Avoid PHP 7.1 warning of passing $this by reference
1340                 $outputPage = $this;
1341                 # Add the remaining categories to the skin
1342                 if ( Hooks::run(
1343                         'OutputPageMakeCategoryLinks',
1344                         [ &$outputPage, $categories, &$this->mCategoryLinks ] )
1345                 ) {
1346                         $services = MediaWikiServices::getInstance();
1347                         $linkRenderer = $services->getLinkRenderer();
1348                         foreach ( $categories as $category => $type ) {
1349                                 // array keys will cast numeric category names to ints, so cast back to string
1350                                 $category = (string)$category;
1351                                 $origcategory = $category;
1352                                 $title = Title::makeTitleSafe( NS_CATEGORY, $category );
1353                                 if ( !$title ) {
1354                                         continue;
1355                                 }
1356                                 $services->getContentLanguage()->findVariantLink( $category, $title, true );
1357                                 if ( $category != $origcategory && array_key_exists( $category, $categories ) ) {
1358                                         continue;
1359                                 }
1360                                 $text = $services->getContentLanguage()->convertHtml( $title->getText() );
1361                                 $this->mCategories[$type][] = $title->getText();
1362                                 $this->mCategoryLinks[$type][] = $linkRenderer->makeLink( $title, new HtmlArmor( $text ) );
1363                         }
1364                 }
1365         }
1366
1367         /**
1368          * @param array $categories
1369          * @return bool|IResultWrapper
1370          */
1371         protected function addCategoryLinksToLBAndGetResult( array $categories ) {
1372                 # Add the links to a LinkBatch
1373                 $arr = [ NS_CATEGORY => $categories ];
1374                 $lb = new LinkBatch;
1375                 $lb->setArray( $arr );
1376
1377                 # Fetch existence plus the hiddencat property
1378                 $dbr = wfGetDB( DB_REPLICA );
1379                 $fields = array_merge(
1380                         LinkCache::getSelectFields(),
1381                         [ 'page_namespace', 'page_title', 'pp_value' ]
1382                 );
1383
1384                 $res = $dbr->select( [ 'page', 'page_props' ],
1385                         $fields,
1386                         $lb->constructSet( 'page', $dbr ),
1387                         __METHOD__,
1388                         [],
1389                         [ 'page_props' => [ 'LEFT JOIN', [
1390                                 'pp_propname' => 'hiddencat',
1391                                 'pp_page = page_id'
1392                         ] ] ]
1393                 );
1394
1395                 # Add the results to the link cache
1396                 $linkCache = MediaWikiServices::getInstance()->getLinkCache();
1397                 $lb->addResultToCache( $linkCache, $res );
1398
1399                 return $res;
1400         }
1401
1402         /**
1403          * Reset the category links (but not the category list) and add $categories
1404          *
1405          * @param array $categories Mapping category name => sort key
1406          */
1407         public function setCategoryLinks( array $categories ) {
1408                 $this->mCategoryLinks = [];
1409                 $this->addCategoryLinks( $categories );
1410         }
1411
1412         /**
1413          * Get the list of category links, in a 2-D array with the following format:
1414          * $arr[$type][] = $link, where $type is either "normal" or "hidden" (for
1415          * hidden categories) and $link a HTML fragment with a link to the category
1416          * page
1417          *
1418          * @return array
1419          */
1420         public function getCategoryLinks() {
1421                 return $this->mCategoryLinks;
1422         }
1423
1424         /**
1425          * Get the list of category names this page belongs to.
1426          *
1427          * @param string $type The type of categories which should be returned. Possible values:
1428          *  * all: all categories of all types
1429          *  * hidden: only the hidden categories
1430          *  * normal: all categories, except hidden categories
1431          * @return array Array of strings
1432          */
1433         public function getCategories( $type = 'all' ) {
1434                 if ( $type === 'all' ) {
1435                         $allCategories = [];
1436                         foreach ( $this->mCategories as $categories ) {
1437                                 $allCategories = array_merge( $allCategories, $categories );
1438                         }
1439                         return $allCategories;
1440                 }
1441                 if ( !isset( $this->mCategories[$type] ) ) {
1442                         throw new InvalidArgumentException( 'Invalid category type given: ' . $type );
1443                 }
1444                 return $this->mCategories[$type];
1445         }
1446
1447         /**
1448          * Add an array of indicators, with their identifiers as array
1449          * keys and HTML contents as values.
1450          *
1451          * In case of duplicate keys, existing values are overwritten.
1452          *
1453          * @param array $indicators
1454          * @since 1.25
1455          */
1456         public function setIndicators( array $indicators ) {
1457                 $this->mIndicators = $indicators + $this->mIndicators;
1458                 // Keep ordered by key
1459                 ksort( $this->mIndicators );
1460         }
1461
1462         /**
1463          * Get the indicators associated with this page.
1464          *
1465          * The array will be internally ordered by item keys.
1466          *
1467          * @return array Keys: identifiers, values: HTML contents
1468          * @since 1.25
1469          */
1470         public function getIndicators() {
1471                 return $this->mIndicators;
1472         }
1473
1474         /**
1475          * Adds help link with an icon via page indicators.
1476          * Link target can be overridden by a local message containing a wikilink:
1477          * the message key is: lowercase action or special page name + '-helppage'.
1478          * @param string $to Target MediaWiki.org page title or encoded URL.
1479          * @param bool $overrideBaseUrl Whether $url is a full URL, to avoid MW.o.
1480          * @since 1.25
1481          */
1482         public function addHelpLink( $to, $overrideBaseUrl = false ) {
1483                 $this->addModuleStyles( 'mediawiki.helplink' );
1484                 $text = $this->msg( 'helppage-top-gethelp' )->escaped();
1485
1486                 if ( $overrideBaseUrl ) {
1487                         $helpUrl = $to;
1488                 } else {
1489                         $toUrlencoded = wfUrlencode( str_replace( ' ', '_', $to ) );
1490                         $helpUrl = "//www.mediawiki.org/wiki/Special:MyLanguage/$toUrlencoded";
1491                 }
1492
1493                 $link = Html::rawElement(
1494                         'a',
1495                         [
1496                                 'href' => $helpUrl,
1497                                 'target' => '_blank',
1498                                 'class' => 'mw-helplink',
1499                         ],
1500                         $text
1501                 );
1502
1503                 $this->setIndicators( [ 'mw-helplink' => $link ] );
1504         }
1505
1506         /**
1507          * Do not allow scripts which can be modified by wiki users to load on this page;
1508          * only allow scripts bundled with, or generated by, the software.
1509          * Site-wide styles are controlled by a config setting, since they can be
1510          * used to create a custom skin/theme, but not user-specific ones.
1511          *
1512          * @todo this should be given a more accurate name
1513          */
1514         public function disallowUserJs() {
1515                 $this->reduceAllowedModules(
1516                         ResourceLoaderModule::TYPE_SCRIPTS,
1517                         ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
1518                 );
1519
1520                 // Site-wide styles are controlled by a config setting, see T73621
1521                 // for background on why. User styles are never allowed.
1522                 if ( $this->getConfig()->get( 'AllowSiteCSSOnRestrictedPages' ) ) {
1523                         $styleOrigin = ResourceLoaderModule::ORIGIN_USER_SITEWIDE;
1524                 } else {
1525                         $styleOrigin = ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL;
1526                 }
1527                 $this->reduceAllowedModules(
1528                         ResourceLoaderModule::TYPE_STYLES,
1529                         $styleOrigin
1530                 );
1531         }
1532
1533         /**
1534          * Show what level of JavaScript / CSS untrustworthiness is allowed on this page
1535          * @see ResourceLoaderModule::$origin
1536          * @param string $type ResourceLoaderModule TYPE_ constant
1537          * @return int ResourceLoaderModule ORIGIN_ class constant
1538          */
1539         public function getAllowedModules( $type ) {
1540                 if ( $type == ResourceLoaderModule::TYPE_COMBINED ) {
1541                         return min( array_values( $this->mAllowedModules ) );
1542                 } else {
1543                         return $this->mAllowedModules[$type] ?? ResourceLoaderModule::ORIGIN_ALL;
1544                 }
1545         }
1546
1547         /**
1548          * Limit the highest level of CSS/JS untrustworthiness allowed.
1549          *
1550          * If passed the same or a higher level than the current level of untrustworthiness set, the
1551          * level will remain unchanged.
1552          *
1553          * @param string $type
1554          * @param int $level ResourceLoaderModule class constant
1555          */
1556         public function reduceAllowedModules( $type, $level ) {
1557                 $this->mAllowedModules[$type] = min( $this->getAllowedModules( $type ), $level );
1558         }
1559
1560         /**
1561          * Prepend $text to the body HTML
1562          *
1563          * @param string $text HTML
1564          */
1565         public function prependHTML( $text ) {
1566                 $this->mBodytext = $text . $this->mBodytext;
1567         }
1568
1569         /**
1570          * Append $text to the body HTML
1571          *
1572          * @param string $text HTML
1573          */
1574         public function addHTML( $text ) {
1575                 $this->mBodytext .= $text;
1576         }
1577
1578         /**
1579          * Shortcut for adding an Html::element via addHTML.
1580          *
1581          * @since 1.19
1582          *
1583          * @param string $element
1584          * @param array $attribs
1585          * @param string $contents
1586          */
1587         public function addElement( $element, array $attribs = [], $contents = '' ) {
1588                 $this->addHTML( Html::element( $element, $attribs, $contents ) );
1589         }
1590
1591         /**
1592          * Clear the body HTML
1593          */
1594         public function clearHTML() {
1595                 $this->mBodytext = '';
1596         }
1597
1598         /**
1599          * Get the body HTML
1600          *
1601          * @return string HTML
1602          */
1603         public function getHTML() {
1604                 return $this->mBodytext;
1605         }
1606
1607         /**
1608          * Get/set the ParserOptions object to use for wikitext parsing
1609          *
1610          * @param ParserOptions|null $options Either the ParserOption to use or null to only get the
1611          *   current ParserOption object. This parameter is deprecated since 1.31.
1612          * @return ParserOptions
1613          */
1614         public function parserOptions( $options = null ) {
1615                 if ( $options !== null ) {
1616                         wfDeprecated( __METHOD__ . ' with non-null $options', '1.31' );
1617                 }
1618
1619                 if ( $options !== null && !empty( $options->isBogus ) ) {
1620                         // Someone is trying to set a bogus pre-$wgUser PO. Check if it has
1621                         // been changed somehow, and keep it if so.
1622                         $anonPO = ParserOptions::newFromAnon();
1623                         $anonPO->setAllowUnsafeRawHtml( false );
1624                         if ( !$options->matches( $anonPO ) ) {
1625                                 wfLogWarning( __METHOD__ . ': Setting a changed bogus ParserOptions: ' . wfGetAllCallers( 5 ) );
1626                                 $options->isBogus = false;
1627                         }
1628                 }
1629
1630                 if ( !$this->mParserOptions ) {
1631                         if ( !$this->getUser()->isSafeToLoad() ) {
1632                                 // $wgUser isn't unstubbable yet, so don't try to get a
1633                                 // ParserOptions for it. And don't cache this ParserOptions
1634                                 // either.
1635                                 $po = ParserOptions::newFromAnon();
1636                                 $po->setAllowUnsafeRawHtml( false );
1637                                 $po->isBogus = true;
1638                                 if ( $options !== null ) {
1639                                         $this->mParserOptions = empty( $options->isBogus ) ? $options : null;
1640                                 }
1641                                 return $po;
1642                         }
1643
1644                         $this->mParserOptions = ParserOptions::newFromContext( $this->getContext() );
1645                         $this->mParserOptions->setAllowUnsafeRawHtml( false );
1646                 }
1647
1648                 if ( $options !== null && !empty( $options->isBogus ) ) {
1649                         // They're trying to restore the bogus pre-$wgUser PO. Do the right
1650                         // thing.
1651                         return wfSetVar( $this->mParserOptions, null, true );
1652                 } else {
1653                         return wfSetVar( $this->mParserOptions, $options );
1654                 }
1655         }
1656
1657         /**
1658          * Set the revision ID which will be seen by the wiki text parser
1659          * for things such as embedded {{REVISIONID}} variable use.
1660          *
1661          * @param int|null $revid A positive integer, or null
1662          * @return mixed Previous value
1663          */
1664         public function setRevisionId( $revid ) {
1665                 $val = is_null( $revid ) ? null : intval( $revid );
1666                 return wfSetVar( $this->mRevisionId, $val, true );
1667         }
1668
1669         /**
1670          * Get the displayed revision ID
1671          *
1672          * @return int
1673          */
1674         public function getRevisionId() {
1675                 return $this->mRevisionId;
1676         }
1677
1678         /**
1679          * Set the timestamp of the revision which will be displayed. This is used
1680          * to avoid a extra DB call in Skin::lastModified().
1681          *
1682          * @param string|null $timestamp
1683          * @return mixed Previous value
1684          */
1685         public function setRevisionTimestamp( $timestamp ) {
1686                 return wfSetVar( $this->mRevisionTimestamp, $timestamp, true );
1687         }
1688
1689         /**
1690          * Get the timestamp of displayed revision.
1691          * This will be null if not filled by setRevisionTimestamp().
1692          *
1693          * @return string|null
1694          */
1695         public function getRevisionTimestamp() {
1696                 return $this->mRevisionTimestamp;
1697         }
1698
1699         /**
1700          * Set the displayed file version
1701          *
1702          * @param File|null $file
1703          * @return mixed Previous value
1704          */
1705         public function setFileVersion( $file ) {
1706                 $val = null;
1707                 if ( $file instanceof File && $file->exists() ) {
1708                         $val = [ 'time' => $file->getTimestamp(), 'sha1' => $file->getSha1() ];
1709                 }
1710                 return wfSetVar( $this->mFileVersion, $val, true );
1711         }
1712
1713         /**
1714          * Get the displayed file version
1715          *
1716          * @return array|null ('time' => MW timestamp, 'sha1' => sha1)
1717          */
1718         public function getFileVersion() {
1719                 return $this->mFileVersion;
1720         }
1721
1722         /**
1723          * Get the templates used on this page
1724          *
1725          * @return array (namespace => dbKey => revId)
1726          * @since 1.18
1727          */
1728         public function getTemplateIds() {
1729                 return $this->mTemplateIds;
1730         }
1731
1732         /**
1733          * Get the files used on this page
1734          *
1735          * @return array (dbKey => array('time' => MW timestamp or null, 'sha1' => sha1 or ''))
1736          * @since 1.18
1737          */
1738         public function getFileSearchOptions() {
1739                 return $this->mImageTimeKeys;
1740         }
1741
1742         /**
1743          * Convert wikitext to HTML and add it to the buffer
1744          * Default assumes that the current page title will be used.
1745          *
1746          * @param string $text
1747          * @param bool $linestart Is this the start of a line?
1748          * @param bool $interface Is this text in the user interface language?
1749          * @throws MWException
1750          * @deprecated since 1.32 due to untidy output; use
1751          *    addWikiTextAsInterface() if $interface is default value or true,
1752          *    or else addWikiTextAsContent() if $interface is false.
1753          */
1754         public function addWikiText( $text, $linestart = true, $interface = true ) {
1755                 wfDeprecated( __METHOD__, '1.32' );
1756                 $title = $this->getTitle();
1757                 if ( !$title ) {
1758                         throw new MWException( 'Title is null' );
1759                 }
1760                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/false, $interface );
1761         }
1762
1763         /**
1764          * Convert wikitext *in the user interface language* to HTML and
1765          * add it to the buffer. The result will not be
1766          * language-converted, as user interface messages are already
1767          * localized into a specific variant.  Assumes that the current
1768          * page title will be used if optional $title is not
1769          * provided. Output will be tidy.
1770          *
1771          * @param string $text Wikitext in the user interface language
1772          * @param bool $linestart Is this the start of a line? (Defaults to true)
1773          * @param Title|null $title Optional title to use; default of `null`
1774          *   means use current page title.
1775          * @throws MWException if $title is not provided and OutputPage::getTitle()
1776          *   is null
1777          * @since 1.32
1778          */
1779         public function addWikiTextAsInterface(
1780                 $text, $linestart = true, Title $title = null
1781         ) {
1782                 if ( $title === null ) {
1783                         $title = $this->getTitle();
1784                 }
1785                 if ( !$title ) {
1786                         throw new MWException( 'Title is null' );
1787                 }
1788                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/true, /*interface*/true );
1789         }
1790
1791         /**
1792          * Convert wikitext *in the user interface language* to HTML and
1793          * add it to the buffer with a `<div class="$wrapperClass">`
1794          * wrapper.  The result will not be language-converted, as user
1795          * interface messages as already localized into a specific
1796          * variant.  The $text will be parsed in start-of-line context.
1797          * Output will be tidy.
1798          *
1799          * @param string $wrapperClass The class attribute value for the <div>
1800          *   wrapper in the output HTML
1801          * @param string $text Wikitext in the user interface language
1802          * @since 1.32
1803          */
1804         public function wrapWikiTextAsInterface(
1805                 $wrapperClass, $text
1806         ) {
1807                 $this->addWikiTextTitleInternal(
1808                         $text, $this->getTitle(),
1809                         /*linestart*/true, /*tidy*/true, /*interface*/true,
1810                         $wrapperClass
1811                 );
1812         }
1813
1814         /**
1815          * Convert wikitext *in the page content language* to HTML and add
1816          * it to the buffer.  The result with be language-converted to the
1817          * user's preferred variant.  Assumes that the current page title
1818          * will be used if optional $title is not provided. Output will be
1819          * tidy.
1820          *
1821          * @param string $text Wikitext in the page content language
1822          * @param bool $linestart Is this the start of a line? (Defaults to true)
1823          * @param Title|null $title Optional title to use; default of `null`
1824          *   means use current page title.
1825          * @throws MWException if $title is not provided and OutputPage::getTitle()
1826          *   is null
1827          * @since 1.32
1828          */
1829         public function addWikiTextAsContent(
1830                 $text, $linestart = true, Title $title = null
1831         ) {
1832                 if ( $title === null ) {
1833                         $title = $this->getTitle();
1834                 }
1835                 if ( !$title ) {
1836                         throw new MWException( 'Title is null' );
1837                 }
1838                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/true, /*interface*/false );
1839         }
1840
1841         /**
1842          * Add wikitext with a custom Title object
1843          *
1844          * @param string $text Wikitext
1845          * @param Title $title
1846          * @param bool $linestart Is this the start of a line?
1847          * @deprecated since 1.32 due to untidy output; use
1848          *   addWikiTextAsInterface()
1849          */
1850         public function addWikiTextWithTitle( $text, Title $title, $linestart = true ) {
1851                 wfDeprecated( __METHOD__, '1.32' );
1852                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/false, /*interface*/false );
1853         }
1854
1855         /**
1856          * Add wikitext *in content language* with a custom Title object.
1857          * Output will be tidy.
1858          *
1859          * @param string $text Wikitext in content language
1860          * @param Title $title
1861          * @param bool $linestart Is this the start of a line?
1862          * @deprecated since 1.32 to rename methods consistently; use
1863          *   addWikiTextAsContent()
1864          */
1865         function addWikiTextTitleTidy( $text, Title $title, $linestart = true ) {
1866                 wfDeprecated( __METHOD__, '1.32' );
1867                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/true, /*interface*/false );
1868         }
1869
1870         /**
1871          * Add wikitext *in content language*. Output will be tidy.
1872          *
1873          * @param string $text Wikitext in content language
1874          * @param bool $linestart Is this the start of a line?
1875          * @deprecated since 1.32 to rename methods consistently; use
1876          *   addWikiTextAsContent()
1877          */
1878         public function addWikiTextTidy( $text, $linestart = true ) {
1879                 wfDeprecated( __METHOD__, '1.32' );
1880                 $title = $this->getTitle();
1881                 if ( !$title ) {
1882                         throw new MWException( 'Title is null' );
1883                 }
1884                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/true, /*interface*/false );
1885         }
1886
1887         /**
1888          * Add wikitext with a custom Title object.
1889          * Output is unwrapped.
1890          *
1891          * @param string $text Wikitext
1892          * @param Title $title
1893          * @param bool $linestart Is this the start of a line?
1894          * @param bool $tidy Whether to use tidy.
1895          *             Setting this to false (or omitting it) is deprecated
1896          *             since 1.32; all wikitext should be tidied.
1897          *             For backwards-compatibility with prior MW releases,
1898          *             you may wish to invoke this method but set $tidy=true;
1899          *             this will result in equivalent output to the non-deprecated
1900          *             addWikiTextAsContent()/addWikiTextAsInterface() methods.
1901          * @param bool $interface Whether it is an interface message
1902          *   (for example disables conversion)
1903          * @deprecated since 1.32, use addWikiTextAsContent() or
1904          *   addWikiTextAsInterface() (depending on $interface)
1905          */
1906         public function addWikiTextTitle( $text, Title $title, $linestart,
1907                 $tidy = false, $interface = false
1908         ) {
1909                 wfDeprecated( __METHOD__, '1.32' );
1910                 return $this->addWikiTextTitleInternal( $text, $title, $linestart, $tidy, $interface );
1911         }
1912
1913         /**
1914          * Add wikitext with a custom Title object.
1915          * Output is unwrapped.
1916          *
1917          * @param string $text Wikitext
1918          * @param Title $title
1919          * @param bool $linestart Is this the start of a line?
1920          * @param bool $tidy Whether to use tidy.
1921          *             Setting this to false (or omitting it) is deprecated
1922          *             since 1.32; all wikitext should be tidied.
1923          * @param bool $interface Whether it is an interface message
1924          *   (for example disables conversion)
1925          * @param string $wrapperClass if not empty, wraps the output in
1926          *   a `<div class="$wrapperClass">`
1927          * @private
1928          */
1929         private function addWikiTextTitleInternal(
1930                 $text, Title $title, $linestart, $tidy, $interface, $wrapperClass = null
1931         ) {
1932                 if ( !$tidy ) {
1933                         wfDeprecated( 'disabling tidy', '1.32' );
1934                 }
1935
1936                 $parserOutput = $this->parseInternal(
1937                         $text, $title, $linestart, $tidy, $interface, /*language*/null
1938                 );
1939
1940                 $this->addParserOutput( $parserOutput, [
1941                         'enableSectionEditLinks' => false,
1942                         'wrapperDivClass' => $wrapperClass ?? '',
1943                 ] );
1944         }
1945
1946         /**
1947          * Add all metadata associated with a ParserOutput object, but without the actual HTML. This
1948          * includes categories, language links, ResourceLoader modules, effects of certain magic words,
1949          * and so on.
1950          *
1951          * @since 1.24
1952          * @param ParserOutput $parserOutput
1953          */
1954         public function addParserOutputMetadata( ParserOutput $parserOutput ) {
1955                 $this->mLanguageLinks =
1956                         array_merge( $this->mLanguageLinks, $parserOutput->getLanguageLinks() );
1957                 $this->addCategoryLinks( $parserOutput->getCategories() );
1958                 $this->setIndicators( $parserOutput->getIndicators() );
1959                 $this->mNewSectionLink = $parserOutput->getNewSection();
1960                 $this->mHideNewSectionLink = $parserOutput->getHideNewSection();
1961
1962                 if ( !$parserOutput->isCacheable() ) {
1963                         $this->enableClientCache( false );
1964                 }
1965                 $this->mNoGallery = $parserOutput->getNoGallery();
1966                 $this->mHeadItems = array_merge( $this->mHeadItems, $parserOutput->getHeadItems() );
1967                 $this->addModules( $parserOutput->getModules() );
1968                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1969                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1970                 $this->mPreventClickjacking = $this->mPreventClickjacking
1971                         || $parserOutput->preventClickjacking();
1972
1973                 // Template versioning...
1974                 foreach ( (array)$parserOutput->getTemplateIds() as $ns => $dbks ) {
1975                         if ( isset( $this->mTemplateIds[$ns] ) ) {
1976                                 $this->mTemplateIds[$ns] = $dbks + $this->mTemplateIds[$ns];
1977                         } else {
1978                                 $this->mTemplateIds[$ns] = $dbks;
1979                         }
1980                 }
1981                 // File versioning...
1982                 foreach ( (array)$parserOutput->getFileSearchOptions() as $dbk => $data ) {
1983                         $this->mImageTimeKeys[$dbk] = $data;
1984                 }
1985
1986                 // Hooks registered in the object
1987                 $parserOutputHooks = $this->getConfig()->get( 'ParserOutputHooks' );
1988                 foreach ( $parserOutput->getOutputHooks() as $hookInfo ) {
1989                         list( $hookName, $data ) = $hookInfo;
1990                         if ( isset( $parserOutputHooks[$hookName] ) ) {
1991                                 $parserOutputHooks[$hookName]( $this, $parserOutput, $data );
1992                         }
1993                 }
1994
1995                 // Enable OOUI if requested via ParserOutput
1996                 if ( $parserOutput->getEnableOOUI() ) {
1997                         $this->enableOOUI();
1998                 }
1999
2000                 // Include parser limit report
2001                 if ( !$this->limitReportJSData ) {
2002                         $this->limitReportJSData = $parserOutput->getLimitReportJSData();
2003                 }
2004
2005                 // Link flags are ignored for now, but may in the future be
2006                 // used to mark individual language links.
2007                 $linkFlags = [];
2008                 // Avoid PHP 7.1 warning of passing $this by reference
2009                 $outputPage = $this;
2010                 Hooks::run( 'LanguageLinks', [ $this->getTitle(), &$this->mLanguageLinks, &$linkFlags ] );
2011                 Hooks::runWithoutAbort( 'OutputPageParserOutput', [ &$outputPage, $parserOutput ] );
2012
2013                 // This check must be after 'OutputPageParserOutput' runs in addParserOutputMetadata
2014                 // so that extensions may modify ParserOutput to toggle TOC.
2015                 // This cannot be moved to addParserOutputText because that is not
2016                 // called by EditPage for Preview.
2017                 if ( $parserOutput->getTOCHTML() ) {
2018                         $this->mEnableTOC = true;
2019                 }
2020         }
2021
2022         /**
2023          * Add the HTML and enhancements for it (like ResourceLoader modules) associated with a
2024          * ParserOutput object, without any other metadata.
2025          *
2026          * @since 1.24
2027          * @param ParserOutput $parserOutput
2028          * @param array $poOptions Options to ParserOutput::getText()
2029          */
2030         public function addParserOutputContent( ParserOutput $parserOutput, $poOptions = [] ) {
2031                 $this->addParserOutputText( $parserOutput, $poOptions );
2032
2033                 $this->addModules( $parserOutput->getModules() );
2034                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
2035
2036                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
2037         }
2038
2039         /**
2040          * Add the HTML associated with a ParserOutput object, without any metadata.
2041          *
2042          * @since 1.24
2043          * @param ParserOutput $parserOutput
2044          * @param array $poOptions Options to ParserOutput::getText()
2045          */
2046         public function addParserOutputText( ParserOutput $parserOutput, $poOptions = [] ) {
2047                 $text = $parserOutput->getText( $poOptions );
2048                 // Avoid PHP 7.1 warning of passing $this by reference
2049                 $outputPage = $this;
2050                 Hooks::runWithoutAbort( 'OutputPageBeforeHTML', [ &$outputPage, &$text ] );
2051                 $this->addHTML( $text );
2052         }
2053
2054         /**
2055          * Add everything from a ParserOutput object.
2056          *
2057          * @param ParserOutput $parserOutput
2058          * @param array $poOptions Options to ParserOutput::getText()
2059          */
2060         function addParserOutput( ParserOutput $parserOutput, $poOptions = [] ) {
2061                 $this->addParserOutputMetadata( $parserOutput );
2062                 $this->addParserOutputText( $parserOutput, $poOptions );
2063         }
2064
2065         /**
2066          * Add the output of a QuickTemplate to the output buffer
2067          *
2068          * @param QuickTemplate &$template
2069          */
2070         public function addTemplate( &$template ) {
2071                 $this->addHTML( $template->getHTML() );
2072         }
2073
2074         /**
2075          * Parse wikitext and return the HTML.
2076          *
2077          * @todo The output is wrapped in a <div> iff $interface is false; it's
2078          * probably best to always strip the wrapper.
2079          *
2080          * @param string $text
2081          * @param bool $linestart Is this the start of a line?
2082          * @param bool $interface Use interface language (instead of content language) while parsing
2083          *   language sensitive magic words like GRAMMAR and PLURAL.  This also disables
2084          *   LanguageConverter.
2085          * @param Language|null $language Target language object, will override $interface
2086          * @throws MWException
2087          * @return string HTML
2088          * @deprecated since 1.32, due to untidy output and inconsistent wrapper;
2089          *  use parseAsContent() if $interface is default value or false, or else
2090          *  parseAsInterface() if $interface is true.
2091          */
2092         public function parse( $text, $linestart = true, $interface = false, $language = null ) {
2093                 wfDeprecated( __METHOD__, '1.33' );
2094                 return $this->parseInternal(
2095                         $text, $this->getTitle(), $linestart, /*tidy*/false, $interface, $language
2096                 )->getText( [
2097                         'enableSectionEditLinks' => false,
2098                 ] );
2099         }
2100
2101         /**
2102          * Parse wikitext *in the page content language* and return the HTML.
2103          * The result will be language-converted to the user's preferred variant.
2104          * Output will be tidy.
2105          *
2106          * @param string $text Wikitext in the page content language
2107          * @param bool $linestart Is this the start of a line? (Defaults to true)
2108          * @throws MWException
2109          * @return string HTML
2110          * @since 1.32
2111          */
2112         public function parseAsContent( $text, $linestart = true ) {
2113                 return $this->parseInternal(
2114                         $text, $this->getTitle(), $linestart, /*tidy*/true, /*interface*/false, /*language*/null
2115                 )->getText( [
2116                         'enableSectionEditLinks' => false,
2117                         'wrapperDivClass' => ''
2118                 ] );
2119         }
2120
2121         /**
2122          * Parse wikitext *in the user interface language* and return the HTML.
2123          * The result will not be language-converted, as user interface messages
2124          * are already localized into a specific variant.
2125          * Output will be tidy.
2126          *
2127          * @param string $text Wikitext in the user interface language
2128          * @param bool $linestart Is this the start of a line? (Defaults to true)
2129          * @throws MWException
2130          * @return string HTML
2131          * @since 1.32
2132          */
2133         public function parseAsInterface( $text, $linestart = true ) {
2134                 return $this->parseInternal(
2135                         $text, $this->getTitle(), $linestart, /*tidy*/true, /*interface*/true, /*language*/null
2136                 )->getText( [
2137                         'enableSectionEditLinks' => false,
2138                         'wrapperDivClass' => ''
2139                 ] );
2140         }
2141
2142         /**
2143          * Parse wikitext *in the user interface language*, strip
2144          * paragraph wrapper, and return the HTML.
2145          * The result will not be language-converted, as user interface messages
2146          * are already localized into a specific variant.
2147          * Output will be tidy.  Outer paragraph wrapper will only be stripped
2148          * if the result is a single paragraph.
2149          *
2150          * @param string $text Wikitext in the user interface language
2151          * @param bool $linestart Is this the start of a line? (Defaults to true)
2152          * @throws MWException
2153          * @return string HTML
2154          * @since 1.32
2155          */
2156         public function parseInlineAsInterface( $text, $linestart = true ) {
2157                 return Parser::stripOuterParagraph(
2158                         $this->parseAsInterface( $text, $linestart )
2159                 );
2160         }
2161
2162         /**
2163          * Parse wikitext, strip paragraph wrapper, and return the HTML.
2164          *
2165          * @param string $text
2166          * @param bool $linestart Is this the start of a line?
2167          * @param bool $interface Use interface language (instead of content language) while parsing
2168          *   language sensitive magic words like GRAMMAR and PLURAL
2169          * @return string HTML
2170          * @deprecated since 1.32, due to untidy output and confusing default
2171          *   for $interface.  Use parseInlineAsInterface() if $interface is
2172          *   the default value or false, or else use
2173          *   Parser::stripOuterParagraph($outputPage->parseAsContent(...)).
2174          */
2175         public function parseInline( $text, $linestart = true, $interface = false ) {
2176                 wfDeprecated( __METHOD__, '1.33' );
2177                 $parsed = $this->parseInternal(
2178                         $text, $this->getTitle(), $linestart, /*tidy*/false, $interface, /*language*/null
2179                 )->getText( [
2180                         'enableSectionEditLinks' => false,
2181                         'wrapperDivClass' => '', /* no wrapper div */
2182                 ] );
2183                 return Parser::stripOuterParagraph( $parsed );
2184         }
2185
2186         /**
2187          * Parse wikitext and return the HTML (internal implementation helper)
2188          *
2189          * @param string $text
2190          * @param Title $title The title to use
2191          * @param bool $linestart Is this the start of a line?
2192          * @param bool $tidy Whether the output should be tidied
2193          * @param bool $interface Use interface language (instead of content language) while parsing
2194          *   language sensitive magic words like GRAMMAR and PLURAL.  This also disables
2195          *   LanguageConverter.
2196          * @param Language|null $language Target language object, will override $interface
2197          * @throws MWException
2198          * @return ParserOutput
2199          */
2200         private function parseInternal( $text, $title, $linestart, $tidy, $interface, $language ) {
2201                 global $wgParser;
2202
2203                 if ( is_null( $title ) ) {
2204                         throw new MWException( 'Empty $mTitle in ' . __METHOD__ );
2205                 }
2206
2207                 $popts = $this->parserOptions();
2208                 $oldTidy = $popts->setTidy( $tidy );
2209                 $oldInterface = $popts->setInterfaceMessage( (bool)$interface );
2210
2211                 if ( $language !== null ) {
2212                         $oldLang = $popts->setTargetLanguage( $language );
2213                 }
2214
2215                 $parserOutput = $wgParser->getFreshParser()->parse(
2216                         $text, $title, $popts,
2217                         $linestart, true, $this->mRevisionId
2218                 );
2219
2220                 $popts->setTidy( $oldTidy );
2221                 $popts->setInterfaceMessage( $oldInterface );
2222
2223                 if ( $language !== null ) {
2224                         $popts->setTargetLanguage( $oldLang );
2225                 }
2226
2227                 return $parserOutput;
2228         }
2229
2230         /**
2231          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header
2232          *
2233          * @param int $maxage Maximum cache time on the CDN, in seconds.
2234          */
2235         public function setCdnMaxage( $maxage ) {
2236                 $this->mCdnMaxage = min( $maxage, $this->mCdnMaxageLimit );
2237         }
2238
2239         /**
2240          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header to $maxage if that is
2241          * lower than the current s-maxage.  Either way, $maxage is now an upper limit on s-maxage, so
2242          * that future calls to setCdnMaxage() will no longer be able to raise the s-maxage above
2243          * $maxage.
2244          *
2245          * @param int $maxage Maximum cache time on the CDN, in seconds
2246          * @since 1.27
2247          */
2248         public function lowerCdnMaxage( $maxage ) {
2249                 $this->mCdnMaxageLimit = min( $maxage, $this->mCdnMaxageLimit );
2250                 $this->setCdnMaxage( $this->mCdnMaxage );
2251         }
2252
2253         /**
2254          * Get TTL in [$minTTL,$maxTTL] in pass it to lowerCdnMaxage()
2255          *
2256          * This sets and returns $minTTL if $mtime is false or null. Otherwise,
2257          * the TTL is higher the older the $mtime timestamp is. Essentially, the
2258          * TTL is 90% of the age of the object, subject to the min and max.
2259          *
2260          * @param string|int|float|bool|null $mtime Last-Modified timestamp
2261          * @param int $minTTL Minimum TTL in seconds [default: 1 minute]
2262          * @param int $maxTTL Maximum TTL in seconds [default: $wgSquidMaxage]
2263          * @since 1.28
2264          */
2265         public function adaptCdnTTL( $mtime, $minTTL = 0, $maxTTL = 0 ) {
2266                 $minTTL = $minTTL ?: IExpiringStore::TTL_MINUTE;
2267                 $maxTTL = $maxTTL ?: $this->getConfig()->get( 'SquidMaxage' );
2268
2269                 if ( $mtime === null || $mtime === false ) {
2270                         return $minTTL; // entity does not exist
2271                 }
2272
2273                 $age = MWTimestamp::time() - wfTimestamp( TS_UNIX, $mtime );
2274                 $adaptiveTTL = max( 0.9 * $age, $minTTL );
2275                 $adaptiveTTL = min( $adaptiveTTL, $maxTTL );
2276
2277                 $this->lowerCdnMaxage( (int)$adaptiveTTL );
2278         }
2279
2280         /**
2281          * Use enableClientCache(false) to force it to send nocache headers
2282          *
2283          * @param bool|null $state New value, or null to not set the value
2284          *
2285          * @return bool Old value
2286          */
2287         public function enableClientCache( $state ) {
2288                 return wfSetVar( $this->mEnableClientCache, $state );
2289         }
2290
2291         /**
2292          * Get the list of cookie names that will influence the cache
2293          *
2294          * @return array
2295          */
2296         function getCacheVaryCookies() {
2297                 if ( self::$cacheVaryCookies === null ) {
2298                         $config = $this->getConfig();
2299                         self::$cacheVaryCookies = array_values( array_unique( array_merge(
2300                                 SessionManager::singleton()->getVaryCookies(),
2301                                 [
2302                                         'forceHTTPS',
2303                                 ],
2304                                 $config->get( 'CacheVaryCookies' )
2305                         ) ) );
2306                         Hooks::run( 'GetCacheVaryCookies', [ $this, &self::$cacheVaryCookies ] );
2307                 }
2308                 return self::$cacheVaryCookies;
2309         }
2310
2311         /**
2312          * Check if the request has a cache-varying cookie header
2313          * If it does, it's very important that we don't allow public caching
2314          *
2315          * @return bool
2316          */
2317         function haveCacheVaryCookies() {
2318                 $request = $this->getRequest();
2319                 foreach ( $this->getCacheVaryCookies() as $cookieName ) {
2320                         if ( $request->getCookie( $cookieName, '', '' ) !== '' ) {
2321                                 wfDebug( __METHOD__ . ": found $cookieName\n" );
2322                                 return true;
2323                         }
2324                 }
2325                 wfDebug( __METHOD__ . ": no cache-varying cookies found\n" );
2326                 return false;
2327         }
2328
2329         /**
2330          * Add an HTTP header that will influence on the cache
2331          *
2332          * @param string $header Header name
2333          * @param string[]|null $option Options for the Key header. See
2334          * https://datatracker.ietf.org/doc/draft-fielding-http-key/
2335          * for the list of valid options.
2336          */
2337         public function addVaryHeader( $header, array $option = null ) {
2338                 if ( !array_key_exists( $header, $this->mVaryHeader ) ) {
2339                         $this->mVaryHeader[$header] = [];
2340                 }
2341                 if ( !is_array( $option ) ) {
2342                         $option = [];
2343                 }
2344                 $this->mVaryHeader[$header] =
2345                         array_unique( array_merge( $this->mVaryHeader[$header], $option ) );
2346         }
2347
2348         /**
2349          * Return a Vary: header on which to vary caches. Based on the keys of $mVaryHeader,
2350          * such as Accept-Encoding or Cookie
2351          *
2352          * @return string
2353          */
2354         public function getVaryHeader() {
2355                 // If we vary on cookies, let's make sure it's always included here too.
2356                 if ( $this->getCacheVaryCookies() ) {
2357                         $this->addVaryHeader( 'Cookie' );
2358                 }
2359
2360                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2361                         $this->addVaryHeader( $header, $options );
2362                 }
2363                 return 'Vary: ' . implode( ', ', array_keys( $this->mVaryHeader ) );
2364         }
2365
2366         /**
2367          * Add an HTTP Link: header
2368          *
2369          * @param string $header Header value
2370          */
2371         public function addLinkHeader( $header ) {
2372                 $this->mLinkHeader[] = $header;
2373         }
2374
2375         /**
2376          * Return a Link: header. Based on the values of $mLinkHeader.
2377          *
2378          * @return string
2379          */
2380         public function getLinkHeader() {
2381                 if ( !$this->mLinkHeader ) {
2382                         return false;
2383                 }
2384
2385                 return 'Link: ' . implode( ',', $this->mLinkHeader );
2386         }
2387
2388         /**
2389          * Get a complete Key header
2390          *
2391          * @return string
2392          * @deprecated in 1.32; the IETF spec for this header expired w/o becoming
2393          *   a standard.
2394          */
2395         public function getKeyHeader() {
2396                 wfDeprecated( '$wgUseKeyHeader', '1.32' );
2397
2398                 $cvCookies = $this->getCacheVaryCookies();
2399
2400                 $cookiesOption = [];
2401                 foreach ( $cvCookies as $cookieName ) {
2402                         $cookiesOption[] = 'param=' . $cookieName;
2403                 }
2404                 $this->addVaryHeader( 'Cookie', $cookiesOption );
2405
2406                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2407                         $this->addVaryHeader( $header, $options );
2408                 }
2409
2410                 $headers = [];
2411                 foreach ( $this->mVaryHeader as $header => $option ) {
2412                         $newheader = $header;
2413                         if ( is_array( $option ) && count( $option ) > 0 ) {
2414                                 $newheader .= ';' . implode( ';', $option );
2415                         }
2416                         $headers[] = $newheader;
2417                 }
2418                 $key = 'Key: ' . implode( ',', $headers );
2419
2420                 return $key;
2421         }
2422
2423         /**
2424          * T23672: Add Accept-Language to Vary and Key headers if there's no 'variant' parameter in GET.
2425          *
2426          * For example:
2427          *   /w/index.php?title=Main_page will vary based on Accept-Language; but
2428          *   /w/index.php?title=Main_page&variant=zh-cn will not.
2429          */
2430         private function addAcceptLanguage() {
2431                 $title = $this->getTitle();
2432                 if ( !$title instanceof Title ) {
2433                         return;
2434                 }
2435
2436                 $lang = $title->getPageLanguage();
2437                 if ( !$this->getRequest()->getCheck( 'variant' ) && $lang->hasVariants() ) {
2438                         $variants = $lang->getVariants();
2439                         $aloption = [];
2440                         foreach ( $variants as $variant ) {
2441                                 if ( $variant === $lang->getCode() ) {
2442                                         continue;
2443                                 }
2444
2445                                 // XXX Note that this code is not strictly correct: we
2446                                 // do a case-insensitive match in
2447                                 // LanguageConverter::getHeaderVariant() while the
2448                                 // (abandoned, draft) spec for the `Key` header only
2449                                 // allows case-sensitive matches.  To match the logic
2450                                 // in LanguageConverter::getHeaderVariant() we should
2451                                 // also be looking at fallback variants and deprecated
2452                                 // mediawiki-internal codes, as well as BCP 47
2453                                 // normalized forms.
2454
2455                                 $aloption[] = "substr=$variant";
2456
2457                                 // IE and some other browsers use BCP 47 standards in their Accept-Language header,
2458                                 // like "zh-CN" or "zh-Hant".  We should handle these too.
2459                                 $variantBCP47 = LanguageCode::bcp47( $variant );
2460                                 if ( $variantBCP47 !== $variant ) {
2461                                         $aloption[] = "substr=$variantBCP47";
2462                                 }
2463                         }
2464                         $this->addVaryHeader( 'Accept-Language', $aloption );
2465                 }
2466         }
2467
2468         /**
2469          * Set a flag which will cause an X-Frame-Options header appropriate for
2470          * edit pages to be sent. The header value is controlled by
2471          * $wgEditPageFrameOptions.
2472          *
2473          * This is the default for special pages. If you display a CSRF-protected
2474          * form on an ordinary view page, then you need to call this function.
2475          *
2476          * @param bool $enable
2477          */
2478         public function preventClickjacking( $enable = true ) {
2479                 $this->mPreventClickjacking = $enable;
2480         }
2481
2482         /**
2483          * Turn off frame-breaking. Alias for $this->preventClickjacking(false).
2484          * This can be called from pages which do not contain any CSRF-protected
2485          * HTML form.
2486          */
2487         public function allowClickjacking() {
2488                 $this->mPreventClickjacking = false;
2489         }
2490
2491         /**
2492          * Get the prevent-clickjacking flag
2493          *
2494          * @since 1.24
2495          * @return bool
2496          */
2497         public function getPreventClickjacking() {
2498                 return $this->mPreventClickjacking;
2499         }
2500
2501         /**
2502          * Get the X-Frame-Options header value (without the name part), or false
2503          * if there isn't one. This is used by Skin to determine whether to enable
2504          * JavaScript frame-breaking, for clients that don't support X-Frame-Options.
2505          *
2506          * @return string|false
2507          */
2508         public function getFrameOptions() {
2509                 $config = $this->getConfig();
2510                 if ( $config->get( 'BreakFrames' ) ) {
2511                         return 'DENY';
2512                 } elseif ( $this->mPreventClickjacking && $config->get( 'EditPageFrameOptions' ) ) {
2513                         return $config->get( 'EditPageFrameOptions' );
2514                 }
2515                 return false;
2516         }
2517
2518         /**
2519          * Get the Origin-Trial header values. This is used to enable Chrome Origin
2520          * Trials: https://github.com/GoogleChrome/OriginTrials
2521          *
2522          * @return array
2523          */
2524         private function getOriginTrials() {
2525                 $config = $this->getConfig();
2526
2527                 return $config->get( 'OriginTrials' );
2528         }
2529
2530         private function getReportTo() {
2531                 $config = $this->getConfig();
2532
2533                 $expiry = $config->get( 'ReportToExpiry' );
2534
2535                 if ( !$expiry ) {
2536                         return false;
2537                 }
2538
2539                 $endpoints = $config->get( 'ReportToEndpoints' );
2540
2541                 if ( !$endpoints ) {
2542                         return false;
2543                 }
2544
2545                 $output = [ 'max_age' => $expiry, 'endpoints' => [] ];
2546
2547                 foreach ( $endpoints as $endpoint ) {
2548                         $output['endpoints'][] = [ 'url' => $endpoint ];
2549                 }
2550
2551                 return json_encode( $output, JSON_UNESCAPED_SLASHES );
2552         }
2553
2554         private function getFeaturePolicyReportOnly() {
2555                 $config = $this->getConfig();
2556
2557                 $features = $config->get( 'FeaturePolicyReportOnly' );
2558                 return implode( ';', $features );
2559         }
2560
2561         /**
2562          * Send cache control HTTP headers
2563          */
2564         public function sendCacheControl() {
2565                 $response = $this->getRequest()->response();
2566                 $config = $this->getConfig();
2567
2568                 $this->addVaryHeader( 'Cookie' );
2569                 $this->addAcceptLanguage();
2570
2571                 # don't serve compressed data to clients who can't handle it
2572                 # maintain different caches for logged-in users and non-logged in ones
2573                 $response->header( $this->getVaryHeader() );
2574
2575                 if ( $config->get( 'UseKeyHeader' ) ) {
2576                         $response->header( $this->getKeyHeader() );
2577                 }
2578
2579                 if ( $this->mEnableClientCache ) {
2580                         if (
2581                                 $config->get( 'UseSquid' ) &&
2582                                 !$response->hasCookies() &&
2583                                 !SessionManager::getGlobalSession()->isPersistent() &&
2584                                 !$this->isPrintable() &&
2585                                 $this->mCdnMaxage != 0 &&
2586                                 !$this->haveCacheVaryCookies()
2587                         ) {
2588                                 if ( $config->get( 'UseESI' ) ) {
2589                                         wfDeprecated( '$wgUseESI = true', '1.33' );
2590                                         # We'll purge the proxy cache explicitly, but require end user agents
2591                                         # to revalidate against the proxy on each visit.
2592                                         # Surrogate-Control controls our CDN, Cache-Control downstream caches
2593                                         wfDebug( __METHOD__ .
2594                                                 ": proxy caching with ESI; {$this->mLastModified} **", 'private' );
2595                                         # start with a shorter timeout for initial testing
2596                                         # header( 'Surrogate-Control: max-age=2678400+2678400, content="ESI/1.0"');
2597                                         $response->header(
2598                                                 "Surrogate-Control: max-age={$config->get( 'SquidMaxage' )}" .
2599                                                 "+{$this->mCdnMaxage}, content=\"ESI/1.0\""
2600                                         );
2601                                         $response->header( 'Cache-Control: s-maxage=0, must-revalidate, max-age=0' );
2602                                 } else {
2603                                         # We'll purge the proxy cache for anons explicitly, but require end user agents
2604                                         # to revalidate against the proxy on each visit.
2605                                         # IMPORTANT! The CDN needs to replace the Cache-Control header with
2606                                         # Cache-Control: s-maxage=0, must-revalidate, max-age=0
2607                                         wfDebug( __METHOD__ .
2608                                                 ": local proxy caching; {$this->mLastModified} **", 'private' );
2609                                         # start with a shorter timeout for initial testing
2610                                         # header( "Cache-Control: s-maxage=2678400, must-revalidate, max-age=0" );
2611                                         $response->header( "Cache-Control: " .
2612                                                 "s-maxage={$this->mCdnMaxage}, must-revalidate, max-age=0" );
2613                                 }
2614                         } else {
2615                                 # We do want clients to cache if they can, but they *must* check for updates
2616                                 # on revisiting the page.
2617                                 wfDebug( __METHOD__ . ": private caching; {$this->mLastModified} **", 'private' );
2618                                 $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2619                                 $response->header( "Cache-Control: private, must-revalidate, max-age=0" );
2620                         }
2621                         if ( $this->mLastModified ) {
2622                                 $response->header( "Last-Modified: {$this->mLastModified}" );
2623                         }
2624                 } else {
2625                         wfDebug( __METHOD__ . ": no caching **", 'private' );
2626
2627                         # In general, the absence of a last modified header should be enough to prevent
2628                         # the client from using its cache. We send a few other things just to make sure.
2629                         $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2630                         $response->header( 'Cache-Control: no-cache, no-store, max-age=0, must-revalidate' );
2631                         $response->header( 'Pragma: no-cache' );
2632                 }
2633         }
2634
2635         /**
2636          * Transfer styles and JavaScript modules from skin.
2637          *
2638          * @param Skin $sk to load modules for
2639          */
2640         public function loadSkinModules( $sk ) {
2641                 foreach ( $sk->getDefaultModules() as $group => $modules ) {
2642                         if ( $group === 'styles' ) {
2643                                 foreach ( $modules as $key => $moduleMembers ) {
2644                                         $this->addModuleStyles( $moduleMembers );
2645                                 }
2646                         } else {
2647                                 $this->addModules( $modules );
2648                         }
2649                 }
2650         }
2651
2652         /**
2653          * Finally, all the text has been munged and accumulated into
2654          * the object, let's actually output it:
2655          *
2656          * @param bool $return Set to true to get the result as a string rather than sending it
2657          * @return string|null
2658          * @throws Exception
2659          * @throws FatalError
2660          * @throws MWException
2661          */
2662         public function output( $return = false ) {
2663                 if ( $this->mDoNothing ) {
2664                         return $return ? '' : null;
2665                 }
2666
2667                 $response = $this->getRequest()->response();
2668                 $config = $this->getConfig();
2669
2670                 if ( $this->mRedirect != '' ) {
2671                         # Standards require redirect URLs to be absolute
2672                         $this->mRedirect = wfExpandUrl( $this->mRedirect, PROTO_CURRENT );
2673
2674                         $redirect = $this->mRedirect;
2675                         $code = $this->mRedirectCode;
2676
2677                         if ( Hooks::run( "BeforePageRedirect", [ $this, &$redirect, &$code ] ) ) {
2678                                 if ( $code == '301' || $code == '303' ) {
2679                                         if ( !$config->get( 'DebugRedirects' ) ) {
2680                                                 $response->statusHeader( $code );
2681                                         }
2682                                         $this->mLastModified = wfTimestamp( TS_RFC2822 );
2683                                 }
2684                                 if ( $config->get( 'VaryOnXFP' ) ) {
2685                                         $this->addVaryHeader( 'X-Forwarded-Proto' );
2686                                 }
2687                                 $this->sendCacheControl();
2688
2689                                 $response->header( "Content-Type: text/html; charset=utf-8" );
2690                                 if ( $config->get( 'DebugRedirects' ) ) {
2691                                         $url = htmlspecialchars( $redirect );
2692                                         print "<!DOCTYPE html>\n<html>\n<head>\n<title>Redirect</title>\n</head>\n<body>\n";
2693                                         print "<p>Location: <a href=\"$url\">$url</a></p>\n";
2694                                         print "</body>\n</html>\n";
2695                                 } else {
2696                                         $response->header( 'Location: ' . $redirect );
2697                                 }
2698                         }
2699
2700                         return $return ? '' : null;
2701                 } elseif ( $this->mStatusCode ) {
2702                         $response->statusHeader( $this->mStatusCode );
2703                 }
2704
2705                 # Buffer output; final headers may depend on later processing
2706                 ob_start();
2707
2708                 $response->header( 'Content-type: ' . $config->get( 'MimeType' ) . '; charset=UTF-8' );
2709                 $response->header( 'Content-language: ' .
2710                         MediaWikiServices::getInstance()->getContentLanguage()->getHtmlCode() );
2711
2712                 $linkHeader = $this->getLinkHeader();
2713                 if ( $linkHeader ) {
2714                         $response->header( $linkHeader );
2715                 }
2716
2717                 // Prevent framing, if requested
2718                 $frameOptions = $this->getFrameOptions();
2719                 if ( $frameOptions ) {
2720                         $response->header( "X-Frame-Options: $frameOptions" );
2721                 }
2722
2723                 $originTrials = $this->getOriginTrials();
2724                 foreach ( $originTrials as $originTrial ) {
2725                         $response->header( "Origin-Trial: $originTrial", false );
2726                 }
2727
2728                 $reportTo = $this->getReportTo();
2729                 if ( $reportTo ) {
2730                         $response->header( "Report-To: $reportTo" );
2731                 }
2732
2733                 $featurePolicyReportOnly = $this->getFeaturePolicyReportOnly();
2734                 if ( $featurePolicyReportOnly ) {
2735                         $response->header( "Feature-Policy-Report-Only: $featurePolicyReportOnly" );
2736                 }
2737
2738                 ContentSecurityPolicy::sendHeaders( $this );
2739
2740                 if ( $this->mArticleBodyOnly ) {
2741                         echo $this->mBodytext;
2742                 } else {
2743                         // Enable safe mode if requested (T152169)
2744                         if ( $this->getRequest()->getBool( 'safemode' ) ) {
2745                                 $this->disallowUserJs();
2746                         }
2747
2748                         $sk = $this->getSkin();
2749                         $this->loadSkinModules( $sk );
2750
2751                         MWDebug::addModules( $this );
2752
2753                         // Avoid PHP 7.1 warning of passing $this by reference
2754                         $outputPage = $this;
2755                         // Hook that allows last minute changes to the output page, e.g.
2756                         // adding of CSS or Javascript by extensions.
2757                         Hooks::runWithoutAbort( 'BeforePageDisplay', [ &$outputPage, &$sk ] );
2758
2759                         try {
2760                                 $sk->outputPage();
2761                         } catch ( Exception $e ) {
2762                                 ob_end_clean(); // bug T129657
2763                                 throw $e;
2764                         }
2765                 }
2766
2767                 try {
2768                         // This hook allows last minute changes to final overall output by modifying output buffer
2769                         Hooks::runWithoutAbort( 'AfterFinalPageOutput', [ $this ] );
2770                 } catch ( Exception $e ) {
2771                         ob_end_clean(); // bug T129657
2772                         throw $e;
2773                 }
2774
2775                 $this->sendCacheControl();
2776
2777                 if ( $return ) {
2778                         return ob_get_clean();
2779                 } else {
2780                         ob_end_flush();
2781                         return null;
2782                 }
2783         }
2784
2785         /**
2786          * Prepare this object to display an error page; disable caching and
2787          * indexing, clear the current text and redirect, set the page's title
2788          * and optionally an custom HTML title (content of the "<title>" tag).
2789          *
2790          * @param string|Message $pageTitle Will be passed directly to setPageTitle()
2791          * @param string|Message $htmlTitle Will be passed directly to setHTMLTitle();
2792          *                   optional, if not passed the "<title>" attribute will be
2793          *                   based on $pageTitle
2794          */
2795         public function prepareErrorPage( $pageTitle, $htmlTitle = false ) {
2796                 $this->setPageTitle( $pageTitle );
2797                 if ( $htmlTitle !== false ) {
2798                         $this->setHTMLTitle( $htmlTitle );
2799                 }
2800                 $this->setRobotPolicy( 'noindex,nofollow' );
2801                 $this->setArticleRelated( false );
2802                 $this->enableClientCache( false );
2803                 $this->mRedirect = '';
2804                 $this->clearSubtitle();
2805                 $this->clearHTML();
2806         }
2807
2808         /**
2809          * Output a standard error page
2810          *
2811          * showErrorPage( 'titlemsg', 'pagetextmsg' );
2812          * showErrorPage( 'titlemsg', 'pagetextmsg', [ 'param1', 'param2' ] );
2813          * showErrorPage( 'titlemsg', $messageObject );
2814          * showErrorPage( $titleMessageObject, $messageObject );
2815          *
2816          * @param string|Message $title Message key (string) for page title, or a Message object
2817          * @param string|Message $msg Message key (string) for page text, or a Message object
2818          * @param array $params Message parameters; ignored if $msg is a Message object
2819          */
2820         public function showErrorPage( $title, $msg, $params = [] ) {
2821                 if ( !$title instanceof Message ) {
2822                         $title = $this->msg( $title );
2823                 }
2824
2825                 $this->prepareErrorPage( $title );
2826
2827                 if ( $msg instanceof Message ) {
2828                         if ( $params !== [] ) {
2829                                 trigger_error( 'Argument ignored: $params. The message parameters argument '
2830                                         . 'is discarded when the $msg argument is a Message object instead of '
2831                                         . 'a string.', E_USER_NOTICE );
2832                         }
2833                         $this->addHTML( $msg->parseAsBlock() );
2834                 } else {
2835                         $this->addWikiMsgArray( $msg, $params );
2836                 }
2837
2838                 $this->returnToMain();
2839         }
2840
2841         /**
2842          * Output a standard permission error page
2843          *
2844          * @param array $errors Error message keys or [key, param...] arrays
2845          * @param string|null $action Action that was denied or null if unknown
2846          */
2847         public function showPermissionsErrorPage( array $errors, $action = null ) {
2848                 foreach ( $errors as $key => $error ) {
2849                         $errors[$key] = (array)$error;
2850                 }
2851
2852                 // For some action (read, edit, create and upload), display a "login to do this action"
2853                 // error if all of the following conditions are met:
2854                 // 1. the user is not logged in
2855                 // 2. the only error is insufficient permissions (i.e. no block or something else)
2856                 // 3. the error can be avoided simply by logging in
2857                 if ( in_array( $action, [ 'read', 'edit', 'createpage', 'createtalk', 'upload' ] )
2858                         && $this->getUser()->isAnon() && count( $errors ) == 1 && isset( $errors[0][0] )
2859                         && ( $errors[0][0] == 'badaccess-groups' || $errors[0][0] == 'badaccess-group0' )
2860                         && ( User::groupHasPermission( 'user', $action )
2861                         || User::groupHasPermission( 'autoconfirmed', $action ) )
2862                 ) {
2863                         $displayReturnto = null;
2864
2865                         # Due to T34276, if a user does not have read permissions,
2866                         # $this->getTitle() will just give Special:Badtitle, which is
2867                         # not especially useful as a returnto parameter. Use the title
2868                         # from the request instead, if there was one.
2869                         $request = $this->getRequest();
2870                         $returnto = Title::newFromText( $request->getVal( 'title', '' ) );
2871                         if ( $action == 'edit' ) {
2872                                 $msg = 'whitelistedittext';
2873                                 $displayReturnto = $returnto;
2874                         } elseif ( $action == 'createpage' || $action == 'createtalk' ) {
2875                                 $msg = 'nocreatetext';
2876                         } elseif ( $action == 'upload' ) {
2877                                 $msg = 'uploadnologintext';
2878                         } else { # Read
2879                                 $msg = 'loginreqpagetext';
2880                                 $displayReturnto = Title::newMainPage();
2881                         }
2882
2883                         $query = [];
2884
2885                         if ( $returnto ) {
2886                                 $query['returnto'] = $returnto->getPrefixedText();
2887
2888                                 if ( !$request->wasPosted() ) {
2889                                         $returntoquery = $request->getValues();
2890                                         unset( $returntoquery['title'] );
2891                                         unset( $returntoquery['returnto'] );
2892                                         unset( $returntoquery['returntoquery'] );
2893                                         $query['returntoquery'] = wfArrayToCgi( $returntoquery );
2894                                 }
2895                         }
2896                         $title = SpecialPage::getTitleFor( 'Userlogin' );
2897                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
2898                         $loginUrl = $title->getLinkURL( $query, false, PROTO_RELATIVE );
2899                         $loginLink = $linkRenderer->makeKnownLink(
2900                                 $title,
2901                                 $this->msg( 'loginreqlink' )->text(),
2902                                 [],
2903                                 $query
2904                         );
2905
2906                         $this->prepareErrorPage( $this->msg( 'loginreqtitle' ) );
2907                         $this->addHTML( $this->msg( $msg )->rawParams( $loginLink )->params( $loginUrl )->parse() );
2908
2909                         # Don't return to a page the user can't read otherwise
2910                         # we'll end up in a pointless loop
2911                         if ( $displayReturnto && $displayReturnto->userCan( 'read', $this->getUser() ) ) {
2912                                 $this->returnToMain( null, $displayReturnto );
2913                         }
2914                 } else {
2915                         $this->prepareErrorPage( $this->msg( 'permissionserrors' ) );
2916                         $this->addWikiTextAsInterface( $this->formatPermissionsErrorMessage( $errors, $action ) );
2917                 }
2918         }
2919
2920         /**
2921          * Display an error page indicating that a given version of MediaWiki is
2922          * required to use it
2923          *
2924          * @param mixed $version The version of MediaWiki needed to use the page
2925          */
2926         public function versionRequired( $version ) {
2927                 $this->prepareErrorPage( $this->msg( 'versionrequired', $version ) );
2928
2929                 $this->addWikiMsg( 'versionrequiredtext', $version );
2930                 $this->returnToMain();
2931         }
2932
2933         /**
2934          * Format a list of error messages
2935          *
2936          * @param array $errors Array of arrays returned by Title::getUserPermissionsErrors
2937          * @param string|null $action Action that was denied or null if unknown
2938          * @return string The wikitext error-messages, formatted into a list.
2939          */
2940         public function formatPermissionsErrorMessage( array $errors, $action = null ) {
2941                 if ( $action == null ) {
2942                         $text = $this->msg( 'permissionserrorstext', count( $errors ) )->plain() . "\n\n";
2943                 } else {
2944                         $action_desc = $this->msg( "action-$action" )->plain();
2945                         $text = $this->msg(
2946                                 'permissionserrorstext-withaction',
2947                                 count( $errors ),
2948                                 $action_desc
2949                         )->plain() . "\n\n";
2950                 }
2951
2952                 if ( count( $errors ) > 1 ) {
2953                         $text .= '<ul class="permissions-errors">' . "\n";
2954
2955                         foreach ( $errors as $error ) {
2956                                 $text .= '<li>';
2957                                 $text .= $this->msg( ...$error )->plain();
2958                                 $text .= "</li>\n";
2959                         }
2960                         $text .= '</ul>';
2961                 } else {
2962                         $text .= "<div class=\"permissions-errors\">\n" .
2963                                         $this->msg( ...reset( $errors ) )->plain() .
2964                                         "\n</div>";
2965                 }
2966
2967                 return $text;
2968         }
2969
2970         /**
2971          * Show a warning about replica DB lag
2972          *
2973          * If the lag is higher than $wgSlaveLagCritical seconds,
2974          * then the warning is a bit more obvious. If the lag is
2975          * lower than $wgSlaveLagWarning, then no warning is shown.
2976          *
2977          * @param int $lag Replica lag
2978          */
2979         public function showLagWarning( $lag ) {
2980                 $config = $this->getConfig();
2981                 if ( $lag >= $config->get( 'SlaveLagWarning' ) ) {
2982                         $lag = floor( $lag ); // floor to avoid nano seconds to display
2983                         $message = $lag < $config->get( 'SlaveLagCritical' )
2984                                 ? 'lag-warn-normal'
2985                                 : 'lag-warn-high';
2986                         $wrap = Html::rawElement( 'div', [ 'class' => "mw-{$message}" ], "\n$1\n" );
2987                         $this->wrapWikiMsg( "$wrap\n", [ $message, $this->getLanguage()->formatNum( $lag ) ] );
2988                 }
2989         }
2990
2991         /**
2992          * Output an error page
2993          *
2994          * @note FatalError exception class provides an alternative.
2995          * @param string $message Error to output. Must be escaped for HTML.
2996          */
2997         public function showFatalError( $message ) {
2998                 $this->prepareErrorPage( $this->msg( 'internalerror' ) );
2999
3000                 $this->addHTML( $message );
3001         }
3002
3003         /**
3004          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
3005          */
3006         public function showUnexpectedValueError( $name, $val ) {
3007                 wfDeprecated( __METHOD__, '1.32' );
3008                 $this->showFatalError( $this->msg( 'unexpected', $name, $val )->escaped() );
3009         }
3010
3011         /**
3012          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
3013          */
3014         public function showFileCopyError( $old, $new ) {
3015                 wfDeprecated( __METHOD__, '1.32' );
3016                 $this->showFatalError( $this->msg( 'filecopyerror', $old, $new )->escaped() );
3017         }
3018
3019         /**
3020          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
3021          */
3022         public function showFileRenameError( $old, $new ) {
3023                 wfDeprecated( __METHOD__, '1.32' );
3024                 $this->showFatalError( $this->msg( 'filerenameerror', $old, $new )->escaped() );
3025         }
3026
3027         /**
3028          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
3029          */
3030         public function showFileDeleteError( $name ) {
3031                 wfDeprecated( __METHOD__, '1.32' );
3032                 $this->showFatalError( $this->msg( 'filedeleteerror', $name )->escaped() );
3033         }
3034
3035         /**
3036          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
3037          */
3038         public function showFileNotFoundError( $name ) {
3039                 wfDeprecated( __METHOD__, '1.32' );
3040                 $this->showFatalError( $this->msg( 'filenotfound', $name )->escaped() );
3041         }
3042
3043         /**
3044          * Add a "return to" link pointing to a specified title
3045          *
3046          * @param Title $title Title to link
3047          * @param array $query Query string parameters
3048          * @param string|null $text Text of the link (input is not escaped)
3049          * @param array $options Options array to pass to Linker
3050          */
3051         public function addReturnTo( $title, array $query = [], $text = null, $options = [] ) {
3052                 $linkRenderer = MediaWikiServices::getInstance()
3053                         ->getLinkRendererFactory()->createFromLegacyOptions( $options );
3054                 $link = $this->msg( 'returnto' )->rawParams(
3055                         $linkRenderer->makeLink( $title, $text, [], $query ) )->escaped();
3056                 $this->addHTML( "<p id=\"mw-returnto\">{$link}</p>\n" );
3057         }
3058
3059         /**
3060          * Add a "return to" link pointing to a specified title,
3061          * or the title indicated in the request, or else the main page
3062          *
3063          * @param mixed|null $unused
3064          * @param Title|string|null $returnto Title or String to return to
3065          * @param string|null $returntoquery Query string for the return to link
3066          */
3067         public function returnToMain( $unused = null, $returnto = null, $returntoquery = null ) {
3068                 if ( $returnto == null ) {
3069                         $returnto = $this->getRequest()->getText( 'returnto' );
3070                 }
3071
3072                 if ( $returntoquery == null ) {
3073                         $returntoquery = $this->getRequest()->getText( 'returntoquery' );
3074                 }
3075
3076                 if ( $returnto === '' ) {
3077                         $returnto = Title::newMainPage();
3078                 }
3079
3080                 if ( is_object( $returnto ) ) {
3081                         $titleObj = $returnto;
3082                 } else {
3083                         $titleObj = Title::newFromText( $returnto );
3084                 }
3085                 // We don't want people to return to external interwiki. That
3086                 // might potentially be used as part of a phishing scheme
3087                 if ( !is_object( $titleObj ) || $titleObj->isExternal() ) {
3088                         $titleObj = Title::newMainPage();
3089                 }
3090
3091                 $this->addReturnTo( $titleObj, wfCgiToArray( $returntoquery ) );
3092         }
3093
3094         private function getRlClientContext() {
3095                 if ( !$this->rlClientContext ) {
3096                         $query = ResourceLoader::makeLoaderQuery(
3097                                 [], // modules; not relevant
3098                                 $this->getLanguage()->getCode(),
3099                                 $this->getSkin()->getSkinName(),
3100                                 $this->getUser()->isLoggedIn() ? $this->getUser()->getName() : null,
3101                                 null, // version; not relevant
3102                                 ResourceLoader::inDebugMode(),
3103                                 null, // only; not relevant
3104                                 $this->isPrintable(),
3105                                 $this->getRequest()->getBool( 'handheld' )
3106                         );
3107                         $this->rlClientContext = new ResourceLoaderContext(
3108                                 $this->getResourceLoader(),
3109                                 new FauxRequest( $query )
3110                         );
3111                         if ( $this->contentOverrideCallbacks ) {
3112                                 $this->rlClientContext = new DerivativeResourceLoaderContext( $this->rlClientContext );
3113                                 $this->rlClientContext->setContentOverrideCallback( function ( Title $title ) {
3114                                         foreach ( $this->contentOverrideCallbacks as $callback ) {
3115                                                 $content = $callback( $title );
3116                                                 if ( $content !== null ) {
3117                                                         $text = ContentHandler::getContentText( $content );
3118                                                         if ( strpos( $text, '</script>' ) !== false ) {
3119                                                                 // Proactively replace this so that we can display a message
3120                                                                 // to the user, instead of letting it go to Html::inlineScript(),
3121                                                                 // where it would be considered a server-side issue.
3122                                                                 $titleFormatted = $title->getPrefixedText();
3123                                                                 $content = new JavaScriptContent(
3124                                                                         Xml::encodeJsCall( 'mw.log.error', [
3125                                                                                 "Cannot preview $titleFormatted due to script-closing tag."
3126                                                                         ] )
3127                                                                 );
3128                                                         }
3129                                                         return $content;
3130                                                 }
3131                                         }
3132                                         return null;
3133                                 } );
3134                         }
3135                 }
3136                 return $this->rlClientContext;
3137         }
3138
3139         /**
3140          * Call this to freeze the module queue and JS config and create a formatter.
3141          *
3142          * Depending on the Skin, this may get lazy-initialised in either headElement() or
3143          * getBottomScripts(). See SkinTemplate::prepareQuickTemplate(). Calling this too early may
3144          * cause unexpected side-effects since disallowUserJs() may be called at any time to change
3145          * the module filters retroactively. Skins and extension hooks may also add modules until very
3146          * late in the request lifecycle.
3147          *
3148          * @return ResourceLoaderClientHtml
3149          */
3150         public function getRlClient() {
3151                 if ( !$this->rlClient ) {
3152                         $context = $this->getRlClientContext();
3153                         $rl = $this->getResourceLoader();
3154                         $this->addModules( [
3155                                 'user',
3156                                 'user.options',
3157                                 'user.tokens',
3158                         ] );
3159                         $this->addModuleStyles( [
3160                                 'site.styles',
3161                                 'noscript',
3162                                 'user.styles',
3163                         ] );
3164                         $this->getSkin()->setupSkinUserCss( $this );
3165
3166                         // Prepare exempt modules for buildExemptModules()
3167                         $exemptGroups = [ 'site' => [], 'noscript' => [], 'private' => [], 'user' => [] ];
3168                         $exemptStates = [];
3169                         $moduleStyles = $this->getModuleStyles( /*filter*/ true );
3170
3171                         // Preload getTitleInfo for isKnownEmpty calls below and in ResourceLoaderClientHtml
3172                         // Separate user-specific batch for improved cache-hit ratio.
3173                         $userBatch = [ 'user.styles', 'user' ];
3174                         $siteBatch = array_diff( $moduleStyles, $userBatch );
3175                         $dbr = wfGetDB( DB_REPLICA );
3176                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $siteBatch );
3177                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $userBatch );
3178
3179                         // Filter out modules handled by buildExemptModules()
3180                         $moduleStyles = array_filter( $moduleStyles,
3181                                 function ( $name ) use ( $rl, $context, &$exemptGroups, &$exemptStates ) {
3182                                         $module = $rl->getModule( $name );
3183                                         if ( $module ) {
3184                                                 $group = $module->getGroup();
3185                                                 if ( isset( $exemptGroups[$group] ) ) {
3186                                                         $exemptStates[$name] = 'ready';
3187                                                         if ( !$module->isKnownEmpty( $context ) ) {
3188                                                                 // E.g. Don't output empty <styles>
3189                                                                 $exemptGroups[$group][] = $name;
3190                                                         }
3191                                                         return false;
3192                                                 }
3193                                         }
3194                                         return true;
3195                                 }
3196                         );
3197                         $this->rlExemptStyleModules = $exemptGroups;
3198
3199                         $rlClient = new ResourceLoaderClientHtml( $context, [
3200                                 'target' => $this->getTarget(),
3201                                 'nonce' => $this->getCSPNonce(),
3202                                 // When 'safemode', disallowUserJs(), or reduceAllowedModules() is used
3203                                 // to only restrict modules to ORIGIN_CORE (ie. disallow ORIGIN_USER), the list of
3204                                 // modules enqueud for loading on this page is filtered to just those.
3205                                 // However, to make sure we also apply the restriction to dynamic dependencies and
3206                                 // lazy-loaded modules at run-time on the client-side, pass 'safemode' down to the
3207                                 // StartupModule so that the client-side registry will not contain any restricted
3208                                 // modules either. (T152169, T185303)
3209                                 'safemode' => ( $this->getAllowedModules( ResourceLoaderModule::TYPE_COMBINED )
3210                                         <= ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
3211                                 ) ? '1' : null,
3212                         ] );
3213                         $rlClient->setConfig( $this->getJSVars() );
3214                         $rlClient->setModules( $this->getModules( /*filter*/ true ) );
3215                         $rlClient->setModuleStyles( $moduleStyles );
3216                         $rlClient->setExemptStates( $exemptStates );
3217                         $this->rlClient = $rlClient;
3218                 }
3219                 return $this->rlClient;
3220         }
3221
3222         /**
3223          * @param Skin $sk The given Skin
3224          * @param bool $includeStyle Unused
3225          * @return string The doctype, opening "<html>", and head element.
3226          */
3227         public function headElement( Skin $sk, $includeStyle = true ) {
3228                 $userdir = $this->getLanguage()->getDir();
3229                 $sitedir = MediaWikiServices::getInstance()->getContentLanguage()->getDir();
3230
3231                 $pieces = [];
3232                 $pieces[] = Html::htmlHeader( Sanitizer::mergeAttributes(
3233                         $this->getRlClient()->getDocumentAttributes(),
3234                         $sk->getHtmlElementAttributes()
3235                 ) );
3236                 $pieces[] = Html::openElement( 'head' );
3237
3238                 if ( $this->getHTMLTitle() == '' ) {
3239                         $this->setHTMLTitle( $this->msg( 'pagetitle', $this->getPageTitle() )->inContentLanguage() );
3240                 }
3241
3242                 if ( !Html::isXmlMimeType( $this->getConfig()->get( 'MimeType' ) ) ) {
3243                         // Add <meta charset="UTF-8">
3244                         // This should be before <title> since it defines the charset used by
3245                         // text including the text inside <title>.
3246                         // The spec recommends defining XHTML5's charset using the XML declaration
3247                         // instead of meta.
3248                         // Our XML declaration is output by Html::htmlHeader.
3249                         // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-content-type
3250                         // https://html.spec.whatwg.org/multipage/semantics.html#charset
3251                         $pieces[] = Html::element( 'meta', [ 'charset' => 'UTF-8' ] );
3252                 }
3253
3254                 $pieces[] = Html::element( 'title', null, $this->getHTMLTitle() );
3255                 $pieces[] = $this->getRlClient()->getHeadHtml();
3256                 $pieces[] = $this->buildExemptModules();
3257                 $pieces = array_merge( $pieces, array_values( $this->getHeadLinksArray() ) );
3258                 $pieces = array_merge( $pieces, array_values( $this->mHeadItems ) );
3259
3260                 // Use an IE conditional comment to serve the script only to old IE
3261                 $pieces[] = '<!--[if lt IE 9]>' .
3262                         ResourceLoaderClientHtml::makeLoad(
3263                                 new ResourceLoaderContext(
3264                                         $this->getResourceLoader(),
3265                                         new FauxRequest( [] )
3266                                 ),
3267                                 [ 'html5shiv' ],
3268                                 ResourceLoaderModule::TYPE_SCRIPTS,
3269                                 [ 'sync' => true ],
3270                                 $this->getCSPNonce()
3271                         ) .
3272                         '<![endif]-->';
3273
3274                 $pieces[] = Html::closeElement( 'head' );
3275
3276                 $bodyClasses = $this->mAdditionalBodyClasses;
3277                 $bodyClasses[] = 'mediawiki';
3278
3279                 # Classes for LTR/RTL directionality support
3280                 $bodyClasses[] = $userdir;
3281                 $bodyClasses[] = "sitedir-$sitedir";
3282
3283                 $underline = $this->getUser()->getOption( 'underline' );
3284                 if ( $underline < 2 ) {
3285                         // The following classes can be used here:
3286                         // * mw-underline-always
3287                         // * mw-underline-never
3288                         $bodyClasses[] = 'mw-underline-' . ( $underline ? 'always' : 'never' );
3289                 }
3290
3291                 if ( $this->getLanguage()->capitalizeAllNouns() ) {
3292                         # A <body> class is probably not the best way to do this . . .
3293                         $bodyClasses[] = 'capitalize-all-nouns';
3294                 }
3295
3296                 // Parser feature migration class
3297                 // The idea is that this will eventually be removed, after the wikitext
3298                 // which requires it is cleaned up.
3299                 $bodyClasses[] = 'mw-hide-empty-elt';
3300
3301                 $bodyClasses[] = $sk->getPageClasses( $this->getTitle() );
3302                 $bodyClasses[] = 'skin-' . Sanitizer::escapeClass( $sk->getSkinName() );
3303                 $bodyClasses[] =
3304                         'action-' . Sanitizer::escapeClass( Action::getActionName( $this->getContext() ) );
3305
3306                 $bodyAttrs = [];
3307                 // While the implode() is not strictly needed, it's used for backwards compatibility
3308                 // (this used to be built as a string and hooks likely still expect that).
3309                 $bodyAttrs['class'] = implode( ' ', $bodyClasses );
3310
3311                 // Allow skins and extensions to add body attributes they need
3312                 $sk->addToBodyAttributes( $this, $bodyAttrs );
3313                 Hooks::run( 'OutputPageBodyAttributes', [ $this, $sk, &$bodyAttrs ] );
3314
3315                 $pieces[] = Html::openElement( 'body', $bodyAttrs );
3316
3317                 return self::combineWrappedStrings( $pieces );
3318         }
3319
3320         /**
3321          * Get a ResourceLoader object associated with this OutputPage
3322          *
3323          * @return ResourceLoader
3324          */
3325         public function getResourceLoader() {
3326                 if ( is_null( $this->mResourceLoader ) ) {
3327                         // Lazy-initialise as needed
3328                         $this->mResourceLoader = MediaWikiServices::getInstance()->getResourceLoader();
3329                 }
3330                 return $this->mResourceLoader;
3331         }
3332
3333         /**
3334          * Explicily load or embed modules on a page.
3335          *
3336          * @param array|string $modules One or more module names
3337          * @param string $only ResourceLoaderModule TYPE_ class constant
3338          * @param array $extraQuery [optional] Array with extra query parameters for the request
3339          * @return string|WrappedStringList HTML
3340          */
3341         public function makeResourceLoaderLink( $modules, $only, array $extraQuery = [] ) {
3342                 // Apply 'target' and 'origin' filters
3343                 $modules = $this->filterModules( (array)$modules, null, $only );
3344
3345                 return ResourceLoaderClientHtml::makeLoad(
3346                         $this->getRlClientContext(),
3347                         $modules,
3348                         $only,
3349                         $extraQuery,
3350                         $this->getCSPNonce()
3351                 );
3352         }
3353
3354         /**
3355          * Combine WrappedString chunks and filter out empty ones
3356          *
3357          * @param array $chunks
3358          * @return string|WrappedStringList HTML
3359          */
3360         protected static function combineWrappedStrings( array $chunks ) {
3361                 // Filter out empty values
3362                 $chunks = array_filter( $chunks, 'strlen' );
3363                 return WrappedString::join( "\n", $chunks );
3364         }
3365
3366         /**
3367          * JS stuff to put at the bottom of the `<body>`.
3368          * These are legacy scripts ($this->mScripts), and user JS.
3369          *
3370          * @return string|WrappedStringList HTML
3371          */
3372         public function getBottomScripts() {
3373                 $chunks = [];
3374                 $chunks[] = $this->getRlClient()->getBodyHtml();
3375
3376                 // Legacy non-ResourceLoader scripts
3377                 $chunks[] = $this->mScripts;
3378
3379                 if ( $this->limitReportJSData ) {
3380                         $chunks[] = ResourceLoader::makeInlineScript(
3381                                 ResourceLoader::makeConfigSetScript(
3382                                         [ 'wgPageParseReport' => $this->limitReportJSData ]
3383                                 ),
3384                                 $this->getCSPNonce()
3385                         );
3386                 }
3387
3388                 return self::combineWrappedStrings( $chunks );
3389         }
3390
3391         /**
3392          * Get the javascript config vars to include on this page
3393          *
3394          * @return array Array of javascript config vars
3395          * @since 1.23
3396          */
3397         public function getJsConfigVars() {
3398                 return $this->mJsConfigVars;
3399         }
3400
3401         /**
3402          * Add one or more variables to be set in mw.config in JavaScript
3403          *
3404          * @param string|array $keys Key or array of key/value pairs
3405          * @param mixed|null $value [optional] Value of the configuration variable
3406          */
3407         public function addJsConfigVars( $keys, $value = null ) {
3408                 if ( is_array( $keys ) ) {
3409                         foreach ( $keys as $key => $value ) {
3410                                 $this->mJsConfigVars[$key] = $value;
3411                         }
3412                         return;
3413                 }
3414
3415                 $this->mJsConfigVars[$keys] = $value;
3416         }
3417
3418         /**
3419          * Get an array containing the variables to be set in mw.config in JavaScript.
3420          *
3421          * Do not add things here which can be evaluated in ResourceLoaderStartUpModule
3422          * - in other words, page-independent/site-wide variables (without state).
3423          * You will only be adding bloat to the html page and causing page caches to
3424          * have to be purged on configuration changes.
3425          * @return array
3426          */
3427         public function getJSVars() {
3428                 $curRevisionId = 0;
3429                 $articleId = 0;
3430                 $canonicalSpecialPageName = false; # T23115
3431                 $services = MediaWikiServices::getInstance();
3432
3433                 $title = $this->getTitle();
3434                 $ns = $title->getNamespace();
3435                 $canonicalNamespace = MWNamespace::exists( $ns )
3436                         ? MWNamespace::getCanonicalName( $ns )
3437                         : $title->getNsText();
3438
3439                 $sk = $this->getSkin();
3440                 // Get the relevant title so that AJAX features can use the correct page name
3441                 // when making API requests from certain special pages (T36972).
3442                 $relevantTitle = $sk->getRelevantTitle();
3443                 $relevantUser = $sk->getRelevantUser();
3444
3445                 if ( $ns == NS_SPECIAL ) {
3446                         list( $canonicalSpecialPageName, /*...*/ ) =
3447                                 $services->getSpecialPageFactory()->
3448                                         resolveAlias( $title->getDBkey() );
3449                 } elseif ( $this->canUseWikiPage() ) {
3450                         $wikiPage = $this->getWikiPage();
3451                         $curRevisionId = $wikiPage->getLatest();
3452                         $articleId = $wikiPage->getId();
3453                 }
3454
3455                 $lang = $title->getPageViewLanguage();
3456
3457                 // Pre-process information
3458                 $separatorTransTable = $lang->separatorTransformTable();
3459                 $separatorTransTable = $separatorTransTable ?: [];
3460                 $compactSeparatorTransTable = [
3461                         implode( "\t", array_keys( $separatorTransTable ) ),
3462                         implode( "\t", $separatorTransTable ),
3463                 ];
3464                 $digitTransTable = $lang->digitTransformTable();
3465                 $digitTransTable = $digitTransTable ?: [];
3466                 $compactDigitTransTable = [
3467                         implode( "\t", array_keys( $digitTransTable ) ),
3468                         implode( "\t", $digitTransTable ),
3469                 ];
3470
3471                 $user = $this->getUser();
3472
3473                 $vars = [
3474                         'wgCanonicalNamespace' => $canonicalNamespace,
3475                         'wgCanonicalSpecialPageName' => $canonicalSpecialPageName,
3476                         'wgNamespaceNumber' => $title->getNamespace(),
3477                         'wgPageName' => $title->getPrefixedDBkey(),
3478                         'wgTitle' => $title->getText(),
3479                         'wgCurRevisionId' => $curRevisionId,
3480                         'wgRevisionId' => (int)$this->getRevisionId(),
3481                         'wgArticleId' => $articleId,
3482                         'wgIsArticle' => $this->isArticle(),
3483                         'wgIsRedirect' => $title->isRedirect(),
3484                         'wgAction' => Action::getActionName( $this->getContext() ),
3485                         'wgUserName' => $user->isAnon() ? null : $user->getName(),
3486                         'wgUserGroups' => $user->getEffectiveGroups(),
3487                         'wgCategories' => $this->getCategories(),
3488                         'wgBreakFrames' => $this->getFrameOptions() == 'DENY',
3489                         'wgPageContentLanguage' => $lang->getCode(),
3490                         'wgPageContentModel' => $title->getContentModel(),
3491                         'wgSeparatorTransformTable' => $compactSeparatorTransTable,
3492                         'wgDigitTransformTable' => $compactDigitTransTable,
3493                         'wgDefaultDateFormat' => $lang->getDefaultDateFormat(),
3494                         'wgMonthNames' => $lang->getMonthNamesArray(),
3495                         'wgMonthNamesShort' => $lang->getMonthAbbreviationsArray(),
3496                         'wgRelevantPageName' => $relevantTitle->getPrefixedDBkey(),
3497                         'wgRelevantArticleId' => $relevantTitle->getArticleID(),
3498                         'wgRequestId' => WebRequest::getRequestId(),
3499                         'wgCSPNonce' => $this->getCSPNonce(),
3500                 ];
3501
3502                 if ( $user->isLoggedIn() ) {
3503                         $vars['wgUserId'] = $user->getId();
3504                         $vars['wgUserEditCount'] = $user->getEditCount();
3505                         $userReg = $user->getRegistration();
3506                         $vars['wgUserRegistration'] = $userReg ? wfTimestamp( TS_UNIX, $userReg ) * 1000 : null;
3507                         // Get the revision ID of the oldest new message on the user's talk
3508                         // page. This can be used for constructing new message alerts on
3509                         // the client side.
3510                         $vars['wgUserNewMsgRevisionId'] = $user->getNewMessageRevisionId();
3511                 }
3512
3513                 $contLang = $services->getContentLanguage();
3514                 if ( $contLang->hasVariants() ) {
3515                         $vars['wgUserVariant'] = $contLang->getPreferredVariant();
3516                 }
3517                 // Same test as SkinTemplate
3518                 $vars['wgIsProbablyEditable'] = $title->quickUserCan( 'edit', $user )
3519                         && ( $title->exists() || $title->quickUserCan( 'create', $user ) );
3520
3521                 $vars['wgRelevantPageIsProbablyEditable'] = $relevantTitle
3522                         && $relevantTitle->quickUserCan( 'edit', $user )
3523                         && ( $relevantTitle->exists() || $relevantTitle->quickUserCan( 'create', $user ) );
3524
3525                 foreach ( $title->getRestrictionTypes() as $type ) {
3526                         // Following keys are set in $vars:
3527                         // wgRestrictionCreate, wgRestrictionEdit, wgRestrictionMove, wgRestrictionUpload
3528                         $vars['wgRestriction' . ucfirst( $type )] = $title->getRestrictions( $type );
3529                 }
3530
3531                 if ( $title->isMainPage() ) {
3532                         $vars['wgIsMainPage'] = true;
3533                 }
3534
3535                 if ( $this->mRedirectedFrom ) {
3536                         $vars['wgRedirectedFrom'] = $this->mRedirectedFrom->getPrefixedDBkey();
3537                 }
3538
3539                 if ( $relevantUser ) {
3540                         $vars['wgRelevantUserName'] = $relevantUser->getName();
3541                 }
3542
3543                 // Allow extensions to add their custom variables to the mw.config map.
3544                 // Use the 'ResourceLoaderGetConfigVars' hook if the variable is not
3545                 // page-dependant but site-wide (without state).
3546                 // Alternatively, you may want to use OutputPage->addJsConfigVars() instead.
3547                 Hooks::run( 'MakeGlobalVariablesScript', [ &$vars, $this ] );
3548
3549                 // Merge in variables from addJsConfigVars last
3550                 return array_merge( $vars, $this->getJsConfigVars() );
3551         }
3552
3553         /**
3554          * To make it harder for someone to slip a user a fake
3555          * JavaScript or CSS preview, a random token
3556          * is associated with the login session. If it's not
3557          * passed back with the preview request, we won't render
3558          * the code.
3559          *
3560          * @return bool
3561          */
3562         public function userCanPreview() {
3563                 $request = $this->getRequest();
3564                 if (
3565                         $request->getVal( 'action' ) !== 'submit' ||
3566                         !$request->wasPosted()
3567                 ) {
3568                         return false;
3569                 }
3570
3571                 $user = $this->getUser();
3572
3573                 if ( !$user->isLoggedIn() ) {
3574                         // Anons have predictable edit tokens
3575                         return false;
3576                 }
3577                 if ( !$user->matchEditToken( $request->getVal( 'wpEditToken' ) ) ) {
3578                         return false;
3579                 }
3580
3581                 $title = $this->getTitle();
3582                 $errors = $title->getUserPermissionsErrors( 'edit', $user );
3583                 if ( count( $errors ) !== 0 ) {
3584                         return false;
3585                 }
3586
3587                 return true;
3588         }
3589
3590         /**
3591          * @return array Array in format "link name or number => 'link html'".
3592          */
3593         public function getHeadLinksArray() {
3594                 global $wgVersion;
3595
3596                 $tags = [];
3597                 $config = $this->getConfig();
3598
3599                 $canonicalUrl = $this->mCanonicalUrl;
3600
3601                 $tags['meta-generator'] = Html::element( 'meta', [
3602                         'name' => 'generator',
3603                         'content' => "MediaWiki $wgVersion",
3604                 ] );
3605
3606                 if ( $config->get( 'ReferrerPolicy' ) !== false ) {
3607                         // Per https://w3c.github.io/webappsec-referrer-policy/#unknown-policy-values
3608                         // fallbacks should come before the primary value so we need to reverse the array.
3609                         foreach ( array_reverse( (array)$config->get( 'ReferrerPolicy' ) ) as $i => $policy ) {
3610                                 $tags["meta-referrer-$i"] = Html::element( 'meta', [
3611                                         'name' => 'referrer',
3612                                         'content' => $policy,
3613                                 ] );
3614                         }
3615                 }
3616
3617                 $p = "{$this->mIndexPolicy},{$this->mFollowPolicy}";
3618                 if ( $p !== 'index,follow' ) {
3619                         // http://www.robotstxt.org/wc/meta-user.html
3620                         // Only show if it's different from the default robots policy
3621                         $tags['meta-robots'] = Html::element( 'meta', [
3622                                 'name' => 'robots',
3623                                 'content' => $p,
3624                         ] );
3625                 }
3626
3627                 foreach ( $this->mMetatags as $tag ) {
3628                         if ( strncasecmp( $tag[0], 'http:', 5 ) === 0 ) {
3629                                 $a = 'http-equiv';
3630                                 $tag[0] = substr( $tag[0], 5 );
3631                         } elseif ( strncasecmp( $tag[0], 'og:', 3 ) === 0 ) {
3632                                 $a = 'property';
3633                         } else {
3634                                 $a = 'name';
3635                         }
3636                         $tagName = "meta-{$tag[0]}";
3637                         if ( isset( $tags[$tagName] ) ) {
3638                                 $tagName .= $tag[1];
3639                         }
3640                         $tags[$tagName] = Html::element( 'meta',
3641                                 [
3642                                         $a => $tag[0],
3643                                         'content' => $tag[1]
3644                                 ]
3645                         );
3646                 }
3647
3648                 foreach ( $this->mLinktags as $tag ) {
3649                         $tags[] = Html::element( 'link', $tag );
3650                 }
3651
3652                 # Universal edit button
3653                 if ( $config->get( 'UniversalEditButton' ) && $this->isArticleRelated() ) {
3654                         $user = $this->getUser();
3655                         if ( $this->getTitle()->quickUserCan( 'edit', $user )
3656                                 && ( $this->getTitle()->exists() ||
3657                                         $this->getTitle()->quickUserCan( 'create', $user ) )
3658                         ) {
3659                                 // Original UniversalEditButton
3660                                 $msg = $this->msg( 'edit' )->text();
3661                                 $tags['universal-edit-button'] = Html::element( 'link', [
3662                                         'rel' => 'alternate',
3663                                         'type' => 'application/x-wiki',
3664                                         'title' => $msg,
3665                                         'href' => $this->getTitle()->getEditURL(),
3666                                 ] );
3667                                 // Alternate edit link
3668                                 $tags['alternative-edit'] = Html::element( 'link', [
3669                                         'rel' => 'edit',
3670                                         'title' => $msg,
3671                                         'href' => $this->getTitle()->getEditURL(),
3672                                 ] );
3673                         }
3674                 }
3675
3676                 # Generally the order of the favicon and apple-touch-icon links
3677                 # should not matter, but Konqueror (3.5.9 at least) incorrectly
3678                 # uses whichever one appears later in the HTML source. Make sure
3679                 # apple-touch-icon is specified first to avoid this.
3680                 if ( $config->get( 'AppleTouchIcon' ) !== false ) {
3681                         $tags['apple-touch-icon'] = Html::element( 'link', [
3682                                 'rel' => 'apple-touch-icon',
3683                                 'href' => $config->get( 'AppleTouchIcon' )
3684                         ] );
3685                 }
3686
3687                 if ( $config->get( 'Favicon' ) !== false ) {
3688                         $tags['favicon'] = Html::element( 'link', [
3689                                 'rel' => 'shortcut icon',
3690                                 'href' => $config->get( 'Favicon' )
3691                         ] );
3692                 }
3693
3694                 # OpenSearch description link
3695                 $tags['opensearch'] = Html::element( 'link', [
3696                         'rel' => 'search',
3697                         'type' => 'application/opensearchdescription+xml',
3698                         'href' => wfScript( 'opensearch_desc' ),
3699                         'title' => $this->msg( 'opensearch-desc' )->inContentLanguage()->text(),
3700                 ] );
3701
3702                 # Real Simple Discovery link, provides auto-discovery information
3703                 # for the MediaWiki API (and potentially additional custom API
3704                 # support such as WordPress or Twitter-compatible APIs for a
3705                 # blogging extension, etc)
3706                 $tags['rsd'] = Html::element( 'link', [
3707                         'rel' => 'EditURI',
3708                         'type' => 'application/rsd+xml',
3709                         // Output a protocol-relative URL here if $wgServer is protocol-relative.
3710                         // Whether RSD accepts relative or protocol-relative URLs is completely
3711                         // undocumented, though.
3712                         'href' => wfExpandUrl( wfAppendQuery(
3713                                 wfScript( 'api' ),
3714                                 [ 'action' => 'rsd' ] ),
3715                                 PROTO_RELATIVE
3716                         ),
3717                 ] );
3718
3719                 # Language variants
3720                 if ( !$config->get( 'DisableLangConversion' ) ) {
3721                         $lang = $this->getTitle()->getPageLanguage();
3722                         if ( $lang->hasVariants() ) {
3723                                 $variants = $lang->getVariants();
3724                                 foreach ( $variants as $variant ) {
3725                                         $tags["variant-$variant"] = Html::element( 'link', [
3726                                                 'rel' => 'alternate',
3727                                                 'hreflang' => LanguageCode::bcp47( $variant ),
3728                                                 'href' => $this->getTitle()->getLocalURL(
3729                                                         [ 'variant' => $variant ] )
3730                                                 ]
3731                                         );
3732                                 }
3733                                 # x-default link per https://support.google.com/webmasters/answer/189077?hl=en
3734                                 $tags["variant-x-default"] = Html::element( 'link', [
3735                                         'rel' => 'alternate',
3736                                         'hreflang' => 'x-default',
3737                                         'href' => $this->getTitle()->getLocalURL() ] );
3738                         }
3739                 }
3740
3741                 # Copyright
3742                 if ( $this->copyrightUrl !== null ) {
3743                         $copyright = $this->copyrightUrl;
3744                 } else {
3745                         $copyright = '';
3746                         if ( $config->get( 'RightsPage' ) ) {
3747                                 $copy = Title::newFromText( $config->get( 'RightsPage' ) );
3748
3749                                 if ( $copy ) {
3750                                         $copyright = $copy->getLocalURL();
3751                                 }
3752                         }
3753
3754                         if ( !$copyright && $config->get( 'RightsUrl' ) ) {
3755                                 $copyright = $config->get( 'RightsUrl' );
3756                         }
3757                 }
3758
3759                 if ( $copyright ) {
3760                         $tags['copyright'] = Html::element( 'link', [
3761                                 'rel' => 'license',
3762                                 'href' => $copyright ]
3763                         );
3764                 }
3765
3766                 # Feeds
3767                 if ( $config->get( 'Feed' ) ) {
3768                         $feedLinks = [];
3769
3770                         foreach ( $this->getSyndicationLinks() as $format => $link ) {
3771                                 # Use the page name for the title.  In principle, this could
3772                                 # lead to issues with having the same name for different feeds
3773                                 # corresponding to the same page, but we can't avoid that at
3774                                 # this low a level.
3775
3776                                 $feedLinks[] = $this->feedLink(
3777                                         $format,
3778                                         $link,
3779                                         # Used messages: 'page-rss-feed' and 'page-atom-feed' (for an easier grep)
3780                                         $this->msg(
3781                                                 "page-{$format}-feed", $this->getTitle()->getPrefixedText()
3782                                         )->text()
3783                                 );
3784                         }
3785
3786                         # Recent changes feed should appear on every page (except recentchanges,
3787                         # that would be redundant). Put it after the per-page feed to avoid
3788                         # changing existing behavior. It's still available, probably via a
3789                         # menu in your browser. Some sites might have a different feed they'd
3790                         # like to promote instead of the RC feed (maybe like a "Recent New Articles"
3791                         # or "Breaking news" one). For this, we see if $wgOverrideSiteFeed is defined.
3792                         # If so, use it instead.
3793                         $sitename = $config->get( 'Sitename' );
3794                         $overrideSiteFeed = $config->get( 'OverrideSiteFeed' );
3795                         if ( $overrideSiteFeed ) {
3796                                 foreach ( $overrideSiteFeed as $type => $feedUrl ) {
3797                                         // Note, this->feedLink escapes the url.
3798                                         $feedLinks[] = $this->feedLink(
3799                                                 $type,
3800                                                 $feedUrl,
3801                                                 $this->msg( "site-{$type}-feed", $sitename )->text()
3802                                         );
3803                                 }
3804                         } elseif ( !$this->getTitle()->isSpecial( 'Recentchanges' ) ) {
3805                                 $rctitle = SpecialPage::getTitleFor( 'Recentchanges' );
3806                                 foreach ( $this->getAdvertisedFeedTypes() as $format ) {
3807                                         $feedLinks[] = $this->feedLink(
3808                                                 $format,
3809                                                 $rctitle->getLocalURL( [ 'feed' => $format ] ),
3810                                                 # For grep: 'site-rss-feed', 'site-atom-feed'
3811                                                 $this->msg( "site-{$format}-feed", $sitename )->text()
3812                                         );
3813                                 }
3814                         }
3815
3816                         # Allow extensions to change the list pf feeds. This hook is primarily for changing,
3817                         # manipulating or removing existing feed tags. If you want to add new feeds, you should
3818                         # use OutputPage::addFeedLink() instead.
3819                         Hooks::run( 'AfterBuildFeedLinks', [ &$feedLinks ] );
3820
3821                         $tags += $feedLinks;
3822                 }
3823
3824                 # Canonical URL
3825                 if ( $config->get( 'EnableCanonicalServerLink' ) ) {
3826                         if ( $canonicalUrl !== false ) {
3827                                 $canonicalUrl = wfExpandUrl( $canonicalUrl, PROTO_CANONICAL );
3828                         } elseif ( $this->isArticleRelated() ) {
3829                                 // This affects all requests where "setArticleRelated" is true. This is
3830                                 // typically all requests that show content (query title, curid, oldid, diff),
3831                                 // and all wikipage actions (edit, delete, purge, info, history etc.).
3832                                 // It does not apply to File pages and Special pages.
3833                                 // 'history' and 'info' actions address page metadata rather than the page
3834                                 // content itself, so they may not be canonicalized to the view page url.
3835                                 // TODO: this ought to be better encapsulated in the Action class.
3836                                 $action = Action::getActionName( $this->getContext() );
3837                                 if ( in_array( $action, [ 'history', 'info' ] ) ) {
3838                                         $query = "action={$action}";
3839                                 } else {
3840                                         $query = '';
3841                                 }
3842                                 $canonicalUrl = $this->getTitle()->getCanonicalURL( $query );
3843                         } else {
3844                                 $reqUrl = $this->getRequest()->getRequestURL();
3845                                 $canonicalUrl = wfExpandUrl( $reqUrl, PROTO_CANONICAL );
3846                         }
3847                 }
3848                 if ( $canonicalUrl !== false ) {
3849                         $tags[] = Html::element( 'link', [
3850                                 'rel' => 'canonical',
3851                                 'href' => $canonicalUrl
3852                         ] );
3853                 }
3854
3855                 // Allow extensions to add, remove and/or otherwise manipulate these links
3856                 // If you want only to *add* <head> links, please use the addHeadItem()
3857                 // (or addHeadItems() for multiple items) method instead.
3858                 // This hook is provided as a last resort for extensions to modify these
3859                 // links before the output is sent to client.
3860                 Hooks::run( 'OutputPageAfterGetHeadLinksArray', [ &$tags, $this ] );
3861
3862                 return $tags;
3863         }
3864
3865         /**
3866          * Generate a "<link rel/>" for a feed.
3867          *
3868          * @param string $type Feed type
3869          * @param string $url URL to the feed
3870          * @param string $text Value of the "title" attribute
3871          * @return string HTML fragment
3872          */
3873         private function feedLink( $type, $url, $text ) {
3874                 return Html::element( 'link', [
3875                         'rel' => 'alternate',
3876                         'type' => "application/$type+xml",
3877                         'title' => $text,
3878                         'href' => $url ]
3879                 );
3880         }
3881
3882         /**
3883          * Add a local or specified stylesheet, with the given media options.
3884          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3885          *
3886          * @param string $style URL to the file
3887          * @param string $media To specify a media type, 'screen', 'printable', 'handheld' or any.
3888          * @param string $condition For IE conditional comments, specifying an IE version
3889          * @param string $dir Set to 'rtl' or 'ltr' for direction-specific sheets
3890          */
3891         public function addStyle( $style, $media = '', $condition = '', $dir = '' ) {
3892                 $options = [];
3893                 if ( $media ) {
3894                         $options['media'] = $media;
3895                 }
3896                 if ( $condition ) {
3897                         $options['condition'] = $condition;
3898                 }
3899                 if ( $dir ) {
3900                         $options['dir'] = $dir;
3901                 }
3902                 $this->styles[$style] = $options;
3903         }
3904
3905         /**
3906          * Adds inline CSS styles
3907          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3908          *
3909          * @param mixed $style_css Inline CSS
3910          * @param string $flip Set to 'flip' to flip the CSS if needed
3911          */
3912         public function addInlineStyle( $style_css, $flip = 'noflip' ) {
3913                 if ( $flip === 'flip' && $this->getLanguage()->isRTL() ) {
3914                         # If wanted, and the interface is right-to-left, flip the CSS
3915                         $style_css = CSSJanus::transform( $style_css, true, false );
3916                 }
3917                 $this->mInlineStyles .= Html::inlineStyle( $style_css );
3918         }
3919
3920         /**
3921          * Build exempt modules and legacy non-ResourceLoader styles.
3922          *
3923          * @return string|WrappedStringList HTML
3924          */
3925         protected function buildExemptModules() {
3926                 $chunks = [];
3927                 // Things that go after the ResourceLoaderDynamicStyles marker
3928                 $append = [];
3929
3930                 // We want site, private and user styles to override dynamically added styles from
3931                 // general modules, but we want dynamically added styles to override statically added
3932                 // style modules. So the order has to be:
3933                 // - page style modules (formatted by ResourceLoaderClientHtml::getHeadHtml())
3934                 // - dynamically loaded styles (added by mw.loader before ResourceLoaderDynamicStyles)
3935                 // - ResourceLoaderDynamicStyles marker
3936                 // - site/private/user styles
3937
3938                 // Add legacy styles added through addStyle()/addInlineStyle() here
3939                 $chunks[] = implode( '', $this->buildCssLinksArray() ) . $this->mInlineStyles;
3940
3941                 $chunks[] = Html::element(
3942                         'meta',
3943                         [ 'name' => 'ResourceLoaderDynamicStyles', 'content' => '' ]
3944                 );
3945
3946                 $separateReq = [ 'site.styles', 'user.styles' ];
3947                 foreach ( $this->rlExemptStyleModules as $group => $moduleNames ) {
3948                         // Combinable modules
3949                         $chunks[] = $this->makeResourceLoaderLink(
3950                                 array_diff( $moduleNames, $separateReq ),
3951                                 ResourceLoaderModule::TYPE_STYLES
3952                         );
3953
3954                         foreach ( array_intersect( $moduleNames, $separateReq ) as $name ) {
3955                                 // These require their own dedicated request in order to support "@import"
3956                                 // syntax, which is incompatible with concatenation. (T147667, T37562)
3957                                 $chunks[] = $this->makeResourceLoaderLink( $name,
3958                                         ResourceLoaderModule::TYPE_STYLES
3959                                 );
3960                         }
3961                 }
3962
3963                 return self::combineWrappedStrings( array_merge( $chunks, $append ) );
3964         }
3965
3966         /**
3967          * @return array
3968          */
3969         public function buildCssLinksArray() {
3970                 $links = [];
3971
3972                 foreach ( $this->styles as $file => $options ) {
3973                         $link = $this->styleLink( $file, $options );
3974                         if ( $link ) {
3975                                 $links[$file] = $link;
3976                         }
3977                 }
3978                 return $links;
3979         }
3980
3981         /**
3982          * Generate \<link\> tags for stylesheets
3983          *
3984          * @param string $style URL to the file
3985          * @param array $options Option, can contain 'condition', 'dir', 'media' keys
3986          * @return string HTML fragment
3987          */
3988         protected function styleLink( $style, array $options ) {
3989                 if ( isset( $options['dir'] ) && $this->getLanguage()->getDir() != $options['dir'] ) {
3990                         return '';
3991                 }
3992
3993                 if ( isset( $options['media'] ) ) {
3994                         $media = self::transformCssMedia( $options['media'] );
3995                         if ( is_null( $media ) ) {
3996                                 return '';
3997                         }
3998                 } else {
3999                         $media = 'all';
4000                 }
4001
4002                 if ( substr( $style, 0, 1 ) == '/' ||
4003                         substr( $style, 0, 5 ) == 'http:' ||
4004                         substr( $style, 0, 6 ) == 'https:' ) {
4005                         $url = $style;
4006                 } else {
4007                         $config = $this->getConfig();
4008                         // Append file hash as query parameter
4009                         $url = self::transformResourcePath(
4010                                 $config,
4011                                 $config->get( 'StylePath' ) . '/' . $style
4012                         );
4013                 }
4014
4015                 $link = Html::linkedStyle( $url, $media );
4016
4017                 if ( isset( $options['condition'] ) ) {
4018                         $condition = htmlspecialchars( $options['condition'] );
4019                         $link = "<!--[if $condition]>$link<![endif]-->";
4020                 }
4021                 return $link;
4022         }
4023
4024         /**
4025          * Transform path to web-accessible static resource.
4026          *
4027          * This is used to add a validation hash as query string.
4028          * This aids various behaviors:
4029          *
4030          * - Put long Cache-Control max-age headers on responses for improved
4031          *   cache performance.
4032          * - Get the correct version of a file as expected by the current page.
4033          * - Instantly get the updated version of a file after deployment.
4034          *
4035          * Avoid using this for urls included in HTML as otherwise clients may get different
4036          * versions of a resource when navigating the site depending on when the page was cached.
4037          * If changes to the url propagate, this is not a problem (e.g. if the url is in
4038          * an external stylesheet).
4039          *
4040          * @since 1.27
4041          * @param Config $config
4042          * @param string $path Path-absolute URL to file (from document root, must start with "/")
4043          * @return string URL
4044          */
4045         public static function transformResourcePath( Config $config, $path ) {
4046                 global $IP;
4047
4048                 $localDir = $IP;
4049                 $remotePathPrefix = $config->get( 'ResourceBasePath' );
4050                 if ( $remotePathPrefix === '' ) {
4051                         // The configured base path is required to be empty string for
4052                         // wikis in the domain root
4053                         $remotePath = '/';
4054                 } else {
4055                         $remotePath = $remotePathPrefix;
4056                 }
4057                 if ( strpos( $path, $remotePath ) !== 0 || substr( $path, 0, 2 ) === '//' ) {
4058                         // - Path is outside wgResourceBasePath, ignore.
4059                         // - Path is protocol-relative. Fixes T155310. Not supported by RelPath lib.
4060                         return $path;
4061                 }
4062                 // For files in resources, extensions/ or skins/, ResourceBasePath is preferred here.
4063                 // For other misc files in $IP, we'll fallback to that as well. There is, however, a fourth
4064                 // supported dir/path pair in the configuration (wgUploadDirectory, wgUploadPath)
4065                 // which is not expected to be in wgResourceBasePath on CDNs. (T155146)
4066                 $uploadPath = $config->get( 'UploadPath' );
4067                 if ( strpos( $path, $uploadPath ) === 0 ) {
4068                         $localDir = $config->get( 'UploadDirectory' );
4069                         $remotePathPrefix = $remotePath = $uploadPath;
4070                 }
4071
4072                 $path = RelPath::getRelativePath( $path, $remotePath );
4073                 return self::transformFilePath( $remotePathPrefix, $localDir, $path );
4074         }
4075
4076         /**
4077          * Utility method for transformResourceFilePath().
4078          *
4079          * Caller is responsible for ensuring the file exists. Emits a PHP warning otherwise.
4080          *
4081          * @since 1.27
4082          * @param string $remotePathPrefix URL path prefix that points to $localPath
4083          * @param string $localPath File directory exposed at $remotePath
4084          * @param string $file Path to target file relative to $localPath
4085          * @return string URL
4086          */
4087         public static function transformFilePath( $remotePathPrefix, $localPath, $file ) {
4088                 $hash = md5_file( "$localPath/$file" );
4089                 if ( $hash === false ) {
4090                         wfLogWarning( __METHOD__ . ": Failed to hash $localPath/$file" );
4091                         $hash = '';
4092                 }
4093                 return "$remotePathPrefix/$file?" . substr( $hash, 0, 5 );
4094         }
4095
4096         /**
4097          * Transform "media" attribute based on request parameters
4098          *
4099          * @param string $media Current value of the "media" attribute
4100          * @return string Modified value of the "media" attribute, or null to skip
4101          * this stylesheet
4102          */
4103         public static function transformCssMedia( $media ) {
4104                 global $wgRequest;
4105
4106                 // https://www.w3.org/TR/css3-mediaqueries/#syntax
4107                 $screenMediaQueryRegex = '/^(?:only\s+)?screen\b/i';
4108
4109                 // Switch in on-screen display for media testing
4110                 $switches = [
4111                         'printable' => 'print',
4112                         'handheld' => 'handheld',
4113                 ];
4114                 foreach ( $switches as $switch => $targetMedia ) {
4115                         if ( $wgRequest->getBool( $switch ) ) {
4116                                 if ( $media == $targetMedia ) {
4117                                         $media = '';
4118                                 } elseif ( preg_match( $screenMediaQueryRegex, $media ) === 1 ) {
4119                                         /* This regex will not attempt to understand a comma-separated media_query_list
4120                                          *
4121                                          * Example supported values for $media:
4122                                          * 'screen', 'only screen', 'screen and (min-width: 982px)' ),
4123                                          * Example NOT supported value for $media:
4124                                          * '3d-glasses, screen, print and resolution > 90dpi'
4125                                          *
4126                                          * If it's a print request, we never want any kind of screen stylesheets
4127                                          * If it's a handheld request (currently the only other choice with a switch),
4128                                          * we don't want simple 'screen' but we might want screen queries that
4129                                          * have a max-width or something, so we'll pass all others on and let the
4130                                          * client do the query.
4131                                          */
4132                                         if ( $targetMedia == 'print' || $media == 'screen' ) {
4133                                                 return null;
4134                                         }
4135                                 }
4136                         }
4137                 }
4138
4139                 return $media;
4140         }
4141
4142         /**
4143          * Add a wikitext-formatted message to the output.
4144          * This is equivalent to:
4145          *
4146          *    $wgOut->addWikiText( wfMessage( ... )->plain() )
4147          */
4148         public function addWikiMsg( /*...*/ ) {
4149                 $args = func_get_args();
4150                 $name = array_shift( $args );
4151                 $this->addWikiMsgArray( $name, $args );
4152         }
4153
4154         /**
4155          * Add a wikitext-formatted message to the output.
4156          * Like addWikiMsg() except the parameters are taken as an array
4157          * instead of a variable argument list.
4158          *
4159          * @param string $name
4160          * @param array $args
4161          */
4162         public function addWikiMsgArray( $name, $args ) {
4163                 $this->addHTML( $this->msg( $name, $args )->parseAsBlock() );
4164         }
4165
4166         /**
4167          * This function takes a number of message/argument specifications, wraps them in
4168          * some overall structure, and then parses the result and adds it to the output.
4169          *
4170          * In the $wrap, $1 is replaced with the first message, $2 with the second,
4171          * and so on. The subsequent arguments may be either
4172          * 1) strings, in which case they are message names, or
4173          * 2) arrays, in which case, within each array, the first element is the message
4174          *    name, and subsequent elements are the parameters to that message.
4175          *
4176          * Don't use this for messages that are not in the user's interface language.
4177          *
4178          * For example:
4179          *
4180          *     $wgOut->wrapWikiMsg( "<div class='error'>\n$1\n</div>", 'some-error' );
4181          *
4182          * Is equivalent to:
4183          *
4184          *     $wgOut->addWikiTextAsInterface( "<div class='error'>\n"
4185          *         . wfMessage( 'some-error' )->plain() . "\n</div>" );
4186          *
4187          * The newline after the opening div is needed in some wikitext. See T21226.
4188          *
4189          * @param string $wrap
4190          */
4191         public function wrapWikiMsg( $wrap /*, ...*/ ) {
4192                 $msgSpecs = func_get_args();
4193                 array_shift( $msgSpecs );
4194                 $msgSpecs = array_values( $msgSpecs );
4195                 $s = $wrap;
4196                 foreach ( $msgSpecs as $n => $spec ) {
4197                         if ( is_array( $spec ) ) {
4198                                 $args = $spec;
4199                                 $name = array_shift( $args );
4200                                 if ( isset( $args['options'] ) ) {
4201                                         unset( $args['options'] );
4202                                         wfDeprecated(
4203                                                 'Adding "options" to ' . __METHOD__ . ' is no longer supported',
4204                                                 '1.20'
4205                                         );
4206                                 }
4207                         } else {
4208                                 $args = [];
4209                                 $name = $spec;
4210                         }
4211                         $s = str_replace( '$' . ( $n + 1 ), $this->msg( $name, $args )->plain(), $s );
4212                 }
4213                 $this->addWikiTextAsInterface( $s );
4214         }
4215
4216         /**
4217          * Whether the output has a table of contents
4218          * @return bool
4219          * @since 1.22
4220          */
4221         public function isTOCEnabled() {
4222                 return $this->mEnableTOC;
4223         }
4224
4225         /**
4226          * Enables/disables section edit links, doesn't override __NOEDITSECTION__
4227          * @param bool $flag
4228          * @since 1.23
4229          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
4230          */
4231         public function enableSectionEditLinks( $flag = true ) {
4232                 wfDeprecated( __METHOD__, '1.31' );
4233         }
4234
4235         /**
4236          * @return bool
4237          * @since 1.23
4238          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
4239          */
4240         public function sectionEditLinksEnabled() {
4241                 wfDeprecated( __METHOD__, '1.31' );
4242                 return true;
4243         }
4244
4245         /**
4246          * Helper function to setup the PHP implementation of OOUI to use in this request.
4247          *
4248          * @since 1.26
4249          * @param string $skinName The Skin name to determine the correct OOUI theme
4250          * @param string $dir Language direction
4251          */
4252         public static function setupOOUI( $skinName = 'default', $dir = 'ltr' ) {
4253                 $themes = ResourceLoaderOOUIModule::getSkinThemeMap();
4254                 $theme = $themes[$skinName] ?? $themes['default'];
4255                 // For example, 'OOUI\WikimediaUITheme'.
4256                 $themeClass = "OOUI\\{$theme}Theme";
4257                 OOUI\Theme::setSingleton( new $themeClass() );
4258                 OOUI\Element::setDefaultDir( $dir );
4259         }
4260
4261         /**
4262          * Add ResourceLoader module styles for OOUI and set up the PHP implementation of it for use with
4263          * MediaWiki and this OutputPage instance.
4264          *
4265          * @since 1.25
4266          */
4267         public function enableOOUI() {
4268                 self::setupOOUI(
4269                         strtolower( $this->getSkin()->getSkinName() ),
4270                         $this->getLanguage()->getDir()
4271                 );
4272                 $this->addModuleStyles( [
4273                         'oojs-ui-core.styles',
4274                         'oojs-ui.styles.indicators',
4275                         'oojs-ui.styles.textures',
4276                         'mediawiki.widgets.styles',
4277                         'oojs-ui.styles.icons-content',
4278                         'oojs-ui.styles.icons-alerts',
4279                         'oojs-ui.styles.icons-interactions',
4280                 ] );
4281         }
4282
4283         /**
4284          * Get (and set if not yet set) the CSP nonce.
4285          *
4286          * This value needs to be included in any <script> tags on the
4287          * page.
4288          *
4289          * @return string|bool Nonce or false to mean don't output nonce
4290          * @since 1.32
4291          */
4292         public function getCSPNonce() {
4293                 if ( !ContentSecurityPolicy::isNonceRequired( $this->getConfig() ) ) {
4294                         return false;
4295                 }
4296                 if ( $this->CSPNonce === null ) {
4297                         // XXX It might be expensive to generate randomness
4298                         // on every request, on Windows.
4299                         $rand = random_bytes( 15 );
4300                         $this->CSPNonce = base64_encode( $rand );
4301                 }
4302                 return $this->CSPNonce;
4303         }
4304
4305 }