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 $mModuleScripts = [];
 157
 158         /** @var array */
 159         protected $mModuleStyles = [];
 160
 161         /** @var ResourceLoader */
 162         protected $mResourceLoader;
 163
 164         /** @var ResourceLoaderClientHtml */
 165         private $rlClient;
 166
 167         /** @var ResourceLoaderContext */
 168         private $rlClientContext;
 169
 170         /** @var array */
 171         private $rlExemptStyleModules;
 172
 173         /** @var array */
 174         protected $mJsConfigVars = [];
 175
 176         /** @var array */
 177         protected $mTemplateIds = [];
 178
 179         /** @var array */
 180         protected $mImageTimeKeys = [];
 181
 182         /** @var string */
 183         public $mRedirectCode = '';
 184
 185         protected $mFeedLinksAppendQuery = null;
 186
 187         /** @var array
 188          * What level of 'untrustworthiness' is allowed in CSS/JS modules loaded on this page?
 189          * @see ResourceLoaderModule::$origin
 190          * ResourceLoaderModule::ORIGIN_ALL is assumed unless overridden;
 191          */
 192         protected $mAllowedModules = [
 193                 ResourceLoaderModule::TYPE_COMBINED => ResourceLoaderModule::ORIGIN_ALL,
 194         ];
 195
 196         /** @var bool Whether output is disabled.  If this is true, the 'output' method will do nothing. */
 197         protected $mDoNothing = false;
 198
 199         // Parser related.
 200
 201         /** @var int */
 202         protected $mContainsNewMagic = 0;
 203
 204         /**
 205          * lazy initialised, use parserOptions()
 206          * @var ParserOptions
 207          */
 208         protected $mParserOptions = null;
 209
 210         /**
 211          * Handles the Atom / RSS links.
 212          * We probably only support Atom in 2011.
 213          * @see $wgAdvertisedFeedTypes
 214          */
 215         private $mFeedLinks = [];
 216
 217         // Gwicke work on squid caching? Roughly from 2003.
 218         protected $mEnableClientCache = true;
 219
 220         /** @var bool Flag if output should only contain the body of the article. */
 221         private $mArticleBodyOnly = false;
 222
 223         /** @var bool */
 224         protected $mNewSectionLink = false;
 225
 226         /** @var bool */
 227         protected $mHideNewSectionLink = false;
 228
 229         /**
 230          * @var bool Comes from the parser. This was probably made to load CSS/JS
 231          * only if we had "<gallery>". Used directly in CategoryPage.php.
 232          * Looks like ResourceLoader can replace this.
 233          */
 234         public $mNoGallery = false;
 235
 236         /** @var int Cache stuff. Looks like mEnableClientCache */
 237         protected $mCdnMaxage = 0;
 238         /** @var int Upper limit on mCdnMaxage */
 239         protected $mCdnMaxageLimit = INF;
 240
 241         /**
 242          * @var bool Controls if anti-clickjacking / frame-breaking headers will
 243          * be sent. This should be done for pages where edit actions are possible.
 244          * Setters: $this->preventClickjacking() and $this->allowClickjacking().
 245          */
 246         protected $mPreventClickjacking = true;
 247
 248         /** @var int To include the variable {{REVISIONID}} */
 249         private $mRevisionId = null;
 250
 251         /** @var string */
 252         private $mRevisionTimestamp = null;
 253
 254         /** @var array */
 255         protected $mFileVersion = null;
 256
 257         /**
 258          * @var array An array of stylesheet filenames (relative from skins path),
 259          * with options for CSS media, IE conditions, and RTL/LTR direction.
 260          * For internal use; add settings in the skin via $this->addStyle()
 261          *
 262          * Style again! This seems like a code duplication since we already have
 263          * mStyles. This is what makes Open Source amazing.
 264          */
 265         protected $styles = [];
 266
 267         private $mIndexPolicy = 'index';
 268         private $mFollowPolicy = 'follow';
 269
 270         /**
 271          * @var array Headers that cause the cache to vary.  Key is header name, value is an array of
 272          * options for the Key header.
 273          */
 274         private $mVaryHeader = [
 275                 'Accept-Encoding' => [ 'match=gzip' ],
 276         ];
 277
 278         /**
 279          * If the current page was reached through a redirect, $mRedirectedFrom contains the Title
 280          * of the redirect.
 281          *
 282          * @var Title
 283          */
 284         private $mRedirectedFrom = null;
 285
 286         /**
 287          * Additional key => value data
 288          */
 289         private $mProperties = [];
 290
 291         /**
 292          * @var string|null ResourceLoader target for load.php links. If null, will be omitted
 293          */
 294         private $mTarget = null;
 295
 296         /**
 297          * @var bool Whether parser output contains a table of contents
 298          */
 299         private $mEnableTOC = false;
 300
 301         /**
 302          * @var string|null The URL to send in a <link> element with rel=license
 303          */
 304         private $copyrightUrl;
 305
 306         /** @var array Profiling data */
 307         private $limitReportJSData = [];
 308
 309         /** @var array Map Title to Content */
 310         private $contentOverrides = [];
 311
 312         /** @var callable[] */
 313         private $contentOverrideCallbacks = [];
 314
 315         /**
 316          * Link: header contents
 317          */
 318         private $mLinkHeader = [];
 319
 320         /**
 321          * @var string The nonce for Content-Security-Policy
 322          */
 323         private $CSPNonce;
 324
 325         /**
 326          * @var array A cache of the names of the cookies that will influence the cache
 327          */
 328         private static $cacheVaryCookies = null;
 329
 330         /**
 331          * Constructor for OutputPage. This should not be called directly.
 332          * Instead a new RequestContext should be created and it will implicitly create
 333          * a OutputPage tied to that context.
 334          * @param IContextSource $context
 335          */
 336         function __construct( IContextSource $context ) {
 337                 $this->setContext( $context );
 338         }
 339
 340         /**
 341          * Redirect to $url rather than displaying the normal page
 342          *
 343          * @param string $url
 344          * @param string $responsecode HTTP status code
 345          */
 346         public function redirect( $url, $responsecode = '302' ) {
 347                 # Strip newlines as a paranoia check for header injection in PHP<5.1.2
 348                 $this->mRedirect = str_replace( "\n", '', $url );
 349                 $this->mRedirectCode = $responsecode;
 350         }
 351
 352         /**
 353          * Get the URL to redirect to, or an empty string if not redirect URL set
 354          *
 355          * @return string
 356          */
 357         public function getRedirect() {
 358                 return $this->mRedirect;
 359         }
 360
 361         /**
 362          * Set the copyright URL to send with the output.
 363          * Empty string to omit, null to reset.
 364          *
 365          * @since 1.26
 366          *
 367          * @param string|null $url
 368          */
 369         public function setCopyrightUrl( $url ) {
 370                 $this->copyrightUrl = $url;
 371         }
 372
 373         /**
 374          * Set the HTTP status code to send with the output.
 375          *
 376          * @param int $statusCode
 377          */
 378         public function setStatusCode( $statusCode ) {
 379                 $this->mStatusCode = $statusCode;
 380         }
 381
 382         /**
 383          * Add a new "<meta>" tag
 384          * To add an http-equiv meta tag, precede the name with "http:"
 385          *
 386          * @param string $name Name of the meta tag
 387          * @param string $val Value of the meta tag
 388          */
 389         function addMeta( $name, $val ) {
 390                 array_push( $this->mMetatags, [ $name, $val ] );
 391         }
 392
 393         /**
 394          * Returns the current <meta> tags
 395          *
 396          * @since 1.25
 397          * @return array
 398          */
 399         public function getMetaTags() {
 400                 return $this->mMetatags;
 401         }
 402
 403         /**
 404          * Add a new \<link\> tag to the page header.
 405          *
 406          * Note: use setCanonicalUrl() for rel=canonical.
 407          *
 408          * @param array $linkarr Associative array of attributes.
 409          */
 410         function addLink( array $linkarr ) {
 411                 array_push( $this->mLinktags, $linkarr );
 412         }
 413
 414         /**
 415          * Returns the current <link> tags
 416          *
 417          * @since 1.25
 418          * @return array
 419          */
 420         public function getLinkTags() {
 421                 return $this->mLinktags;
 422         }
 423
 424         /**
 425          * Set the URL to be used for the <link rel=canonical>. This should be used
 426          * in preference to addLink(), to avoid duplicate link tags.
 427          * @param string $url
 428          */
 429         function setCanonicalUrl( $url ) {
 430                 $this->mCanonicalUrl = $url;
 431         }
 432
 433         /**
 434          * Returns the URL to be used for the <link rel=canonical> if
 435          * one is set.
 436          *
 437          * @since 1.25
 438          * @return bool|string
 439          */
 440         public function getCanonicalUrl() {
 441                 return $this->mCanonicalUrl;
 442         }
 443
 444         /**
 445          * Add raw HTML to the list of scripts (including \<script\> tag, etc.)
 446          * Internal use only. Use OutputPage::addModules() or OutputPage::addJsConfigVars()
 447          * if possible.
 448          *
 449          * @param string $script Raw HTML
 450          */
 451         function addScript( $script ) {
 452                 $this->mScripts .= $script;
 453         }
 454
 455         /**
 456          * Add a JavaScript file to be loaded as `<script>` on this page.
 457          *
 458          * Internal use only. Use OutputPage::addModules() if possible.
 459          *
 460          * @param string $file URL to file (absolute path, protocol-relative, or full url)
 461          * @param string|null $unused Previously used to change the cache-busting query parameter
 462          */
 463         public function addScriptFile( $file, $unused = null ) {
 464                 if ( substr( $file, 0, 1 ) !== '/' && !preg_match( '#^[a-z]*://#i', $file ) ) {
 465                         // This is not an absolute path, protocol-relative url, or full scheme url,
 466                         // presumed to be an old call intended to include a file from /w/skins/common,
 467                         // which doesn't exist anymore as of MediaWiki 1.24 per T71277. Ignore.
 468                         wfDeprecated( __METHOD__, '1.24' );
 469                         return;
 470                 }
 471                 $this->addScript( Html::linkedScript( $file, $this->getCSPNonce() ) );
 472         }
 473
 474         /**
 475          * Add a self-contained script tag with the given contents
 476          * Internal use only. Use OutputPage::addModules() if possible.
 477          *
 478          * @param string $script JavaScript text, no script tags
 479          */
 480         public function addInlineScript( $script ) {
 481                 $this->mScripts .= Html::inlineScript( "\n$script\n", $this->getCSPNonce() ) . "\n";
 482         }
 483
 484         /**
 485          * Filter an array of modules to remove insufficiently trustworthy members, and modules
 486          * which are no longer registered (eg a page is cached before an extension is disabled)
 487          * @param array $modules
 488          * @param string|null $position Unused
 489          * @param string $type
 490          * @return array
 491          */
 492         protected function filterModules( array $modules, $position = null,
 493                 $type = ResourceLoaderModule::TYPE_COMBINED
 494         ) {
 495                 $resourceLoader = $this->getResourceLoader();
 496                 $filteredModules = [];
 497                 foreach ( $modules as $val ) {
 498                         $module = $resourceLoader->getModule( $val );
 499                         if ( $module instanceof ResourceLoaderModule
 500                                 && $module->getOrigin() <= $this->getAllowedModules( $type )
 501                         ) {
 502                                 if ( $this->mTarget && !in_array( $this->mTarget, $module->getTargets() ) ) {
 503                                         $this->warnModuleTargetFilter( $module->getName() );
 504                                         continue;
 505                                 }
 506                                 $filteredModules[] = $val;
 507                         }
 508                 }
 509                 return $filteredModules;
 510         }
 511
 512         private function warnModuleTargetFilter( $moduleName ) {
 513                 static $warnings = [];
 514                 if ( isset( $warnings[$this->mTarget][$moduleName] ) ) {
 515                         return;
 516                 }
 517                 $warnings[$this->mTarget][$moduleName] = true;
 518                 $this->getResourceLoader()->getLogger()->debug(
 519                         'Module "{module}" not loadable on target "{target}".',
 520                         [
 521                                 'module' => $moduleName,
 522                                 'target' => $this->mTarget,
 523                         ]
 524                 );
 525         }
 526
 527         /**
 528          * Get the list of modules to include on this page
 529          *
 530          * @param bool $filter Whether to filter out insufficiently trustworthy modules
 531          * @param string|null $position Unused
 532          * @param string $param
 533          * @param string $type
 534          * @return array Array of module names
 535          */
 536         public function getModules( $filter = false, $position = null, $param = 'mModules',
 537                 $type = ResourceLoaderModule::TYPE_COMBINED
 538         ) {
 539                 $modules = array_values( array_unique( $this->$param ) );
 540                 return $filter
 541                         ? $this->filterModules( $modules, null, $type )
 542                         : $modules;
 543         }
 544
 545         /**
 546          * Load one or more ResourceLoader modules on this page.
 547          *
 548          * @param string|array $modules Module name (string) or array of module names
 549          */
 550         public function addModules( $modules ) {
 551                 $this->mModules = array_merge( $this->mModules, (array)$modules );
 552         }
 553
 554         /**
 555          * Get the list of script-only modules to load on this page.
 556          *
 557          * @param bool $filter
 558          * @param string|null $position Unused
 559          * @return array Array of module names
 560          */
 561         public function getModuleScripts( $filter = false, $position = null ) {
 562                 return $this->getModules( $filter, null, 'mModuleScripts',
 563                         ResourceLoaderModule::TYPE_SCRIPTS
 564                 );
 565         }
 566
 567         /**
 568          * Load the scripts of one or more ResourceLoader modules, on this page.
 569          *
 570          * This method exists purely to provide the legacy behaviour of loading
 571          * a module's scripts in the global scope, and without dependency resolution.
 572          * See <https://phabricator.wikimedia.org/T188689>.
 573          *
 574          * @deprecated since 1.31 Use addModules() instead.
 575          * @param string|array $modules Module name (string) or array of module names
 576          */
 577         public function addModuleScripts( $modules ) {
 578                 $this->mModuleScripts = array_merge( $this->mModuleScripts, (array)$modules );
 579         }
 580
 581         /**
 582          * Get the list of style-only modules to load on this page.
 583          *
 584          * @param bool $filter
 585          * @param string|null $position Unused
 586          * @return array Array of module names
 587          */
 588         public function getModuleStyles( $filter = false, $position = null ) {
 589                 return $this->getModules( $filter, null, 'mModuleStyles',
 590                         ResourceLoaderModule::TYPE_STYLES
 591                 );
 592         }
 593
 594         /**
 595          * Load the styles of one or more ResourceLoader modules on this page.
 596          *
 597          * Module styles added through this function will be loaded as a stylesheet,
 598          * using a standard `<link rel=stylesheet>` HTML tag, rather than as a combined
 599          * Javascript and CSS package. Thus, they will even load when JavaScript is disabled.
 600          *
 601          * @param string|array $modules Module name (string) or array of module names
 602          */
 603         public function addModuleStyles( $modules ) {
 604                 $this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
 605         }
 606
 607         /**
 608          * @return null|string ResourceLoader target
 609          */
 610         public function getTarget() {
 611                 return $this->mTarget;
 612         }
 613
 614         /**
 615          * Sets ResourceLoader target for load.php links. If null, will be omitted
 616          *
 617          * @param string|null $target
 618          */
 619         public function setTarget( $target ) {
 620                 $this->mTarget = $target;
 621         }
 622
 623         /**
 624          * Add a mapping from a LinkTarget to a Content, for things like page preview.
 625          * @see self::addContentOverrideCallback()
 626          * @since 1.32
 627          * @param LinkTarget $target
 628          * @param Content $content
 629          */
 630         public function addContentOverride( LinkTarget $target, Content $content ) {
 631                 if ( !$this->contentOverrides ) {
 632                         // Register a callback for $this->contentOverrides on the first call
 633                         $this->addContentOverrideCallback( function ( LinkTarget $target ) {
 634                                 $key = $target->getNamespace() . ':' . $target->getDBkey();
 635                                 return $this->contentOverrides[$key] ?? null;
 636                         } );
 637                 }
 638
 639                 $key = $target->getNamespace() . ':' . $target->getDBkey();
 640                 $this->contentOverrides[$key] = $content;
 641         }
 642
 643         /**
 644          * Add a callback for mapping from a Title to a Content object, for things
 645          * like page preview.
 646          * @see ResourceLoaderContext::getContentOverrideCallback()
 647          * @since 1.32
 648          * @param callable $callback
 649          */
 650         public function addContentOverrideCallback( callable $callback ) {
 651                 $this->contentOverrideCallbacks[] = $callback;
 652         }
 653
 654         /**
 655          * Get an array of head items
 656          *
 657          * @return array
 658          */
 659         function getHeadItemsArray() {
 660                 return $this->mHeadItems;
 661         }
 662
 663         /**
 664          * Add or replace a head item to the output
 665          *
 666          * Whenever possible, use more specific options like ResourceLoader modules,
 667          * OutputPage::addLink(), OutputPage::addMetaLink() and OutputPage::addFeedLink()
 668          * Fallback options for those are: OutputPage::addStyle, OutputPage::addScript(),
 669          * OutputPage::addInlineScript() and OutputPage::addInlineStyle()
 670          * This would be your very LAST fallback.
 671          *
 672          * @param string $name Item name
 673          * @param string $value Raw HTML
 674          */
 675         public function addHeadItem( $name, $value ) {
 676                 $this->mHeadItems[$name] = $value;
 677         }
 678
 679         /**
 680          * Add one or more head items to the output
 681          *
 682          * @since 1.28
 683          * @param string|string[] $values Raw HTML
 684          */
 685         public function addHeadItems( $values ) {
 686                 $this->mHeadItems = array_merge( $this->mHeadItems, (array)$values );
 687         }
 688
 689         /**
 690          * Check if the header item $name is already set
 691          *
 692          * @param string $name Item name
 693          * @return bool
 694          */
 695         public function hasHeadItem( $name ) {
 696                 return isset( $this->mHeadItems[$name] );
 697         }
 698
 699         /**
 700          * Add a class to the <body> element
 701          *
 702          * @since 1.30
 703          * @param string|string[] $classes One or more classes to add
 704          */
 705         public function addBodyClasses( $classes ) {
 706                 $this->mAdditionalBodyClasses = array_merge( $this->mAdditionalBodyClasses, (array)$classes );
 707         }
 708
 709         /**
 710          * Set whether the output should only contain the body of the article,
 711          * without any skin, sidebar, etc.
 712          * Used e.g. when calling with "action=render".
 713          *
 714          * @param bool $only Whether to output only the body of the article
 715          */
 716         public function setArticleBodyOnly( $only ) {
 717                 $this->mArticleBodyOnly = $only;
 718         }
 719
 720         /**
 721          * Return whether the output will contain only the body of the article
 722          *
 723          * @return bool
 724          */
 725         public function getArticleBodyOnly() {
 726                 return $this->mArticleBodyOnly;
 727         }
 728
 729         /**
 730          * Set an additional output property
 731          * @since 1.21
 732          *
 733          * @param string $name
 734          * @param mixed $value
 735          */
 736         public function setProperty( $name, $value ) {
 737                 $this->mProperties[$name] = $value;
 738         }
 739
 740         /**
 741          * Get an additional output property
 742          * @since 1.21
 743          *
 744          * @param string $name
 745          * @return mixed Property value or null if not found
 746          */
 747         public function getProperty( $name ) {
 748                 return $this->mProperties[$name] ?? null;
 749         }
 750
 751         /**
 752          * checkLastModified tells the client to use the client-cached page if
 753          * possible. If successful, the OutputPage is disabled so that
 754          * any future call to OutputPage->output() have no effect.
 755          *
 756          * Side effect: sets mLastModified for Last-Modified header
 757          *
 758          * @param string $timestamp
 759          *
 760          * @return bool True if cache-ok headers was sent.
 761          */
 762         public function checkLastModified( $timestamp ) {
 763                 if ( !$timestamp || $timestamp == '19700101000000' ) {
 764                         wfDebug( __METHOD__ . ": CACHE DISABLED, NO TIMESTAMP\n" );
 765                         return false;
 766                 }
 767                 $config = $this->getConfig();
 768                 if ( !$config->get( 'CachePages' ) ) {
 769                         wfDebug( __METHOD__ . ": CACHE DISABLED\n" );
 770                         return false;
 771                 }
 772
 773                 $timestamp = wfTimestamp( TS_MW, $timestamp );
 774                 $modifiedTimes = [
 775                         'page' => $timestamp,
 776                         'user' => $this->getUser()->getTouched(),
 777                         'epoch' => $config->get( 'CacheEpoch' )
 778                 ];
 779                 if ( $config->get( 'UseSquid' ) ) {
 780                         $modifiedTimes['sepoch'] = wfTimestamp( TS_MW, $this->getCdnCacheEpoch(
 781                                 time(),
 782                                 $config->get( 'SquidMaxage' )
 783                         ) );
 784                 }
 785                 Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this ] );
 786
 787                 $maxModified = max( $modifiedTimes );
 788                 $this->mLastModified = wfTimestamp( TS_RFC2822, $maxModified );
 789
 790                 $clientHeader = $this->getRequest()->getHeader( 'If-Modified-Since' );
 791                 if ( $clientHeader === false ) {
 792                         wfDebug( __METHOD__ . ": client did not send If-Modified-Since header", 'private' );
 793                         return false;
 794                 }
 795
 796                 # IE sends sizes after the date like this:
 797                 # Wed, 20 Aug 2003 06:51:19 GMT; length=5202
 798                 # this breaks strtotime().
 799                 $clientHeader = preg_replace( '/;.*$/', '', $clientHeader );
 800
 801                 Wikimedia\suppressWarnings(); // E_STRICT system time warnings
 802                 $clientHeaderTime = strtotime( $clientHeader );
 803                 Wikimedia\restoreWarnings();
 804                 if ( !$clientHeaderTime ) {
 805                         wfDebug( __METHOD__
 806                                 . ": unable to parse the client's If-Modified-Since header: $clientHeader\n" );
 807                         return false;
 808                 }
 809                 $clientHeaderTime = wfTimestamp( TS_MW, $clientHeaderTime );
 810
 811                 # Make debug info
 812                 $info = '';
 813                 foreach ( $modifiedTimes as $name => $value ) {
 814                         if ( $info !== '' ) {
 815                                 $info .= ', ';
 816                         }
 817                         $info .= "$name=" . wfTimestamp( TS_ISO_8601, $value );
 818                 }
 819
 820                 wfDebug( __METHOD__ . ": client sent If-Modified-Since: " .
 821                         wfTimestamp( TS_ISO_8601, $clientHeaderTime ), 'private' );
 822                 wfDebug( __METHOD__ . ": effective Last-Modified: " .
 823                         wfTimestamp( TS_ISO_8601, $maxModified ), 'private' );
 824                 if ( $clientHeaderTime < $maxModified ) {
 825                         wfDebug( __METHOD__ . ": STALE, $info", 'private' );
 826                         return false;
 827                 }
 828
 829                 # Not modified
 830                 # Give a 304 Not Modified response code and disable body output
 831                 wfDebug( __METHOD__ . ": NOT MODIFIED, $info", 'private' );
 832                 ini_set( 'zlib.output_compression', 0 );
 833                 $this->getRequest()->response()->statusHeader( 304 );
 834                 $this->sendCacheControl();
 835                 $this->disable();
 836
 837                 // Don't output a compressed blob when using ob_gzhandler;
 838                 // it's technically against HTTP spec and seems to confuse
 839                 // Firefox when the response gets split over two packets.
 840                 wfClearOutputBuffers();
 841
 842                 return true;
 843         }
 844
 845         /**
 846          * @param int $reqTime Time of request (eg. now)
 847          * @param int $maxAge Cache TTL in seconds
 848          * @return int Timestamp
 849          */
 850         private function getCdnCacheEpoch( $reqTime, $maxAge ) {
 851                 // Ensure Last-Modified is never more than (wgSquidMaxage) in the past,
 852                 // because even if the wiki page content hasn't changed since, static
 853                 // resources may have changed (skin HTML, interface messages, urls, etc.)
 854                 // and must roll-over in a timely manner (T46570)
 855                 return $reqTime - $maxAge;
 856         }
 857
 858         /**
 859          * Override the last modified timestamp
 860          *
 861          * @param string $timestamp New timestamp, in a format readable by
 862          *        wfTimestamp()
 863          */
 864         public function setLastModified( $timestamp ) {
 865                 $this->mLastModified = wfTimestamp( TS_RFC2822, $timestamp );
 866         }
 867
 868         /**
 869          * Set the robot policy for the page: <http://www.robotstxt.org/meta.html>
 870          *
 871          * @param string $policy The literal string to output as the contents of
 872          *   the meta tag.  Will be parsed according to the spec and output in
 873          *   standardized form.
 874          * @return null
 875          */
 876         public function setRobotPolicy( $policy ) {
 877                 $policy = Article::formatRobotPolicy( $policy );
 878
 879                 if ( isset( $policy['index'] ) ) {
 880                         $this->setIndexPolicy( $policy['index'] );
 881                 }
 882                 if ( isset( $policy['follow'] ) ) {
 883                         $this->setFollowPolicy( $policy['follow'] );
 884                 }
 885         }
 886
 887         /**
 888          * Set the index policy for the page, but leave the follow policy un-
 889          * touched.
 890          *
 891          * @param string $policy Either 'index' or 'noindex'.
 892          * @return null
 893          */
 894         public function setIndexPolicy( $policy ) {
 895                 $policy = trim( $policy );
 896                 if ( in_array( $policy, [ 'index', 'noindex' ] ) ) {
 897                         $this->mIndexPolicy = $policy;
 898                 }
 899         }
 900
 901         /**
 902          * Set the follow policy for the page, but leave the index policy un-
 903          * touched.
 904          *
 905          * @param string $policy Either 'follow' or 'nofollow'.
 906          * @return null
 907          */
 908         public function setFollowPolicy( $policy ) {
 909                 $policy = trim( $policy );
 910                 if ( in_array( $policy, [ 'follow', 'nofollow' ] ) ) {
 911                         $this->mFollowPolicy = $policy;
 912                 }
 913         }
 914
 915         /**
 916          * "HTML title" means the contents of "<title>".
 917          * It is stored as plain, unescaped text and will be run through htmlspecialchars in the skin file.
 918          *
 919          * @param string|Message $name
 920          */
 921         public function setHTMLTitle( $name ) {
 922                 if ( $name instanceof Message ) {
 923                         $this->mHTMLtitle = $name->setContext( $this->getContext() )->text();
 924                 } else {
 925                         $this->mHTMLtitle = $name;
 926                 }
 927         }
 928
 929         /**
 930          * Return the "HTML title", i.e. the content of the "<title>" tag.
 931          *
 932          * @return string
 933          */
 934         public function getHTMLTitle() {
 935                 return $this->mHTMLtitle;
 936         }
 937
 938         /**
 939          * Set $mRedirectedFrom, the Title of the page which redirected us to the current page.
 940          *
 941          * @param Title $t
 942          */
 943         public function setRedirectedFrom( $t ) {
 944                 $this->mRedirectedFrom = $t;
 945         }
 946
 947         /**
 948          * "Page title" means the contents of \<h1\>. It is stored as a valid HTML
 949          * fragment. This function allows good tags like \<sup\> in the \<h1\> tag,
 950          * but not bad tags like \<script\>. This function automatically sets
 951          * \<title\> to the same content as \<h1\> but with all tags removed. Bad
 952          * tags that were escaped in \<h1\> will still be escaped in \<title\>, and
 953          * good tags like \<i\> will be dropped entirely.
 954          *
 955          * @param string|Message $name
 956          * @param-taint $name tainted
 957          * Phan-taint-check gets very confused by $name being either a string or a Message
 958          */
 959         public function setPageTitle( $name ) {
 960                 if ( $name instanceof Message ) {
 961                         $name = $name->setContext( $this->getContext() )->text();
 962                 }
 963
 964                 # change "<script>foo&bar</script>" to "&lt;script&gt;foo&amp;bar&lt;/script&gt;"
 965                 # but leave "<i>foobar</i>" alone
 966                 $nameWithTags = Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $name ) );
 967                 $this->mPageTitle = $nameWithTags;
 968
 969                 # change "<i>foo&amp;bar</i>" to "foo&bar"
 970                 $this->setHTMLTitle(
 971                         $this->msg( 'pagetitle' )->plaintextParams( Sanitizer::stripAllTags( $nameWithTags ) )
 972                                 ->inContentLanguage()
 973                 );
 974         }
 975
 976         /**
 977          * Return the "page title", i.e. the content of the \<h1\> tag.
 978          *
 979          * @return string
 980          */
 981         public function getPageTitle() {
 982                 return $this->mPageTitle;
 983         }
 984
 985         /**
 986          * Same as page title but only contains name of the page, not any other text.
 987          *
 988          * @since 1.32
 989          * @param string $html Page title text.
 990          * @see OutputPage::setPageTitle
 991          */
 992         public function setDisplayTitle( $html ) {
 993                 $this->displayTitle = $html;
 994         }
 995
 996         /**
 997          * Returns page display title.
 998          *
 999          * Performs some normalization, but this not as strict the magic word.
1000          *
1001          * @since 1.32
1002          * @return string HTML
1003          */
1004         public function getDisplayTitle() {
1005                 $html = $this->displayTitle;
1006                 if ( $html === null ) {
1007                         $html = $this->getTitle()->getPrefixedText();
1008                 }
1009
1010                 return Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $html ) );
1011         }
1012
1013         /**
1014          * Returns page display title without namespace prefix if possible.
1015          *
1016          * @since 1.32
1017          * @return string HTML
1018          */
1019         public function getUnprefixedDisplayTitle() {
1020                 $text = $this->getDisplayTitle();
1021                 $nsPrefix = $this->getTitle()->getNsText() . ':';
1022                 $prefix = preg_quote( $nsPrefix, '/' );
1023
1024                 return preg_replace( "/^$prefix/i", '', $text );
1025         }
1026
1027         /**
1028          * Set the Title object to use
1029          *
1030          * @param Title $t
1031          */
1032         public function setTitle( Title $t ) {
1033                 $this->getContext()->setTitle( $t );
1034         }
1035
1036         /**
1037          * Replace the subtitle with $str
1038          *
1039          * @param string|Message $str New value of the subtitle. String should be safe HTML.
1040          */
1041         public function setSubtitle( $str ) {
1042                 $this->clearSubtitle();
1043                 $this->addSubtitle( $str );
1044         }
1045
1046         /**
1047          * Add $str to the subtitle
1048          *
1049          * @param string|Message $str String or Message to add to the subtitle. String should be safe HTML.
1050          */
1051         public function addSubtitle( $str ) {
1052                 if ( $str instanceof Message ) {
1053                         $this->mSubtitle[] = $str->setContext( $this->getContext() )->parse();
1054                 } else {
1055                         $this->mSubtitle[] = $str;
1056                 }
1057         }
1058
1059         /**
1060          * Build message object for a subtitle containing a backlink to a page
1061          *
1062          * @param Title $title Title to link to
1063          * @param array $query Array of additional parameters to include in the link
1064          * @return Message
1065          * @since 1.25
1066          */
1067         public static function buildBacklinkSubtitle( Title $title, $query = [] ) {
1068                 if ( $title->isRedirect() ) {
1069                         $query['redirect'] = 'no';
1070                 }
1071                 $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1072                 return wfMessage( 'backlinksubtitle' )
1073                         ->rawParams( $linkRenderer->makeLink( $title, null, [], $query ) );
1074         }
1075
1076         /**
1077          * Add a subtitle containing a backlink to a page
1078          *
1079          * @param Title $title Title to link to
1080          * @param array $query Array of additional parameters to include in the link
1081          */
1082         public function addBacklinkSubtitle( Title $title, $query = [] ) {
1083                 $this->addSubtitle( self::buildBacklinkSubtitle( $title, $query ) );
1084         }
1085
1086         /**
1087          * Clear the subtitles
1088          */
1089         public function clearSubtitle() {
1090                 $this->mSubtitle = [];
1091         }
1092
1093         /**
1094          * Get the subtitle
1095          *
1096          * @return string
1097          */
1098         public function getSubtitle() {
1099                 return implode( "<br />\n\t\t\t\t", $this->mSubtitle );
1100         }
1101
1102         /**
1103          * Set the page as printable, i.e. it'll be displayed with all
1104          * print styles included
1105          */
1106         public function setPrintable() {
1107                 $this->mPrintable = true;
1108         }
1109
1110         /**
1111          * Return whether the page is "printable"
1112          *
1113          * @return bool
1114          */
1115         public function isPrintable() {
1116                 return $this->mPrintable;
1117         }
1118
1119         /**
1120          * Disable output completely, i.e. calling output() will have no effect
1121          */
1122         public function disable() {
1123                 $this->mDoNothing = true;
1124         }
1125
1126         /**
1127          * Return whether the output will be completely disabled
1128          *
1129          * @return bool
1130          */
1131         public function isDisabled() {
1132                 return $this->mDoNothing;
1133         }
1134
1135         /**
1136          * Show an "add new section" link?
1137          *
1138          * @return bool
1139          */
1140         public function showNewSectionLink() {
1141                 return $this->mNewSectionLink;
1142         }
1143
1144         /**
1145          * Forcibly hide the new section link?
1146          *
1147          * @return bool
1148          */
1149         public function forceHideNewSectionLink() {
1150                 return $this->mHideNewSectionLink;
1151         }
1152
1153         /**
1154          * Add or remove feed links in the page header
1155          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1156          * for the new version
1157          * @see addFeedLink()
1158          *
1159          * @param bool $show True: add default feeds, false: remove all feeds
1160          */
1161         public function setSyndicated( $show = true ) {
1162                 if ( $show ) {
1163                         $this->setFeedAppendQuery( false );
1164                 } else {
1165                         $this->mFeedLinks = [];
1166                 }
1167         }
1168
1169         /**
1170          * Add default feeds to the page header
1171          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1172          * for the new version
1173          * @see addFeedLink()
1174          *
1175          * @param string $val Query to append to feed links or false to output
1176          *        default links
1177          */
1178         public function setFeedAppendQuery( $val ) {
1179                 $this->mFeedLinks = [];
1180
1181                 foreach ( $this->getConfig()->get( 'AdvertisedFeedTypes' ) as $type ) {
1182                         $query = "feed=$type";
1183                         if ( is_string( $val ) ) {
1184                                 $query .= '&' . $val;
1185                         }
1186                         $this->mFeedLinks[$type] = $this->getTitle()->getLocalURL( $query );
1187                 }
1188         }
1189
1190         /**
1191          * Add a feed link to the page header
1192          *
1193          * @param string $format Feed type, should be a key of $wgFeedClasses
1194          * @param string $href URL
1195          */
1196         public function addFeedLink( $format, $href ) {
1197                 if ( in_array( $format, $this->getConfig()->get( 'AdvertisedFeedTypes' ) ) ) {
1198                         $this->mFeedLinks[$format] = $href;
1199                 }
1200         }
1201
1202         /**
1203          * Should we output feed links for this page?
1204          * @return bool
1205          */
1206         public function isSyndicated() {
1207                 return count( $this->mFeedLinks ) > 0;
1208         }
1209
1210         /**
1211          * Return URLs for each supported syndication format for this page.
1212          * @return array Associating format keys with URLs
1213          */
1214         public function getSyndicationLinks() {
1215                 return $this->mFeedLinks;
1216         }
1217
1218         /**
1219          * Will currently always return null
1220          *
1221          * @return null
1222          */
1223         public function getFeedAppendQuery() {
1224                 return $this->mFeedLinksAppendQuery;
1225         }
1226
1227         /**
1228          * Set whether the displayed content is related to the source of the
1229          * corresponding article on the wiki
1230          * Setting true will cause the change "article related" toggle to true
1231          *
1232          * @param bool $newVal
1233          */
1234         public function setArticleFlag( $newVal ) {
1235                 $this->mIsArticle = $newVal;
1236                 if ( $newVal ) {
1237                         $this->mIsArticleRelated = $newVal;
1238                 }
1239         }
1240
1241         /**
1242          * Return whether the content displayed page is related to the source of
1243          * the corresponding article on the wiki
1244          *
1245          * @return bool
1246          */
1247         public function isArticle() {
1248                 return $this->mIsArticle;
1249         }
1250
1251         /**
1252          * Set whether this page is related an article on the wiki
1253          * Setting false will cause the change of "article flag" toggle to false
1254          *
1255          * @param bool $newVal
1256          */
1257         public function setArticleRelated( $newVal ) {
1258                 $this->mIsArticleRelated = $newVal;
1259                 if ( !$newVal ) {
1260                         $this->mIsArticle = false;
1261                 }
1262         }
1263
1264         /**
1265          * Return whether this page is related an article on the wiki
1266          *
1267          * @return bool
1268          */
1269         public function isArticleRelated() {
1270                 return $this->mIsArticleRelated;
1271         }
1272
1273         /**
1274          * Set whether the standard copyright should be shown for the current page.
1275          *
1276          * @param bool $hasCopyright
1277          */
1278         public function setCopyright( $hasCopyright ) {
1279                 $this->mHasCopyright = $hasCopyright;
1280         }
1281
1282         /**
1283          * Return whether the standard copyright should be shown for the current page.
1284          * By default, it is true for all articles but other pages
1285          * can signal it by using setCopyright( true ).
1286          *
1287          * Used by SkinTemplate to decided whether to show the copyright.
1288          *
1289          * @return bool
1290          */
1291         public function showsCopyright() {
1292                 return $this->isArticle() || $this->mHasCopyright;
1293         }
1294
1295         /**
1296          * Add new language links
1297          *
1298          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1299          *                               (e.g. 'fr:Test page')
1300          */
1301         public function addLanguageLinks( array $newLinkArray ) {
1302                 $this->mLanguageLinks = array_merge( $this->mLanguageLinks, $newLinkArray );
1303         }
1304
1305         /**
1306          * Reset the language links and add new language links
1307          *
1308          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1309          *                               (e.g. 'fr:Test page')
1310          */
1311         public function setLanguageLinks( array $newLinkArray ) {
1312                 $this->mLanguageLinks = $newLinkArray;
1313         }
1314
1315         /**
1316          * Get the list of language links
1317          *
1318          * @return string[] Array of interwiki-prefixed (non DB key) titles (e.g. 'fr:Test page')
1319          */
1320         public function getLanguageLinks() {
1321                 return $this->mLanguageLinks;
1322         }
1323
1324         /**
1325          * Add an array of categories, with names in the keys
1326          *
1327          * @param array $categories Mapping category name => sort key
1328          */
1329         public function addCategoryLinks( array $categories ) {
1330                 if ( !$categories ) {
1331                         return;
1332                 }
1333
1334                 $res = $this->addCategoryLinksToLBAndGetResult( $categories );
1335
1336                 # Set all the values to 'normal'.
1337                 $categories = array_fill_keys( array_keys( $categories ), 'normal' );
1338
1339                 # Mark hidden categories
1340                 foreach ( $res as $row ) {
1341                         if ( isset( $row->pp_value ) ) {
1342                                 $categories[$row->page_title] = 'hidden';
1343                         }
1344                 }
1345
1346                 // Avoid PHP 7.1 warning of passing $this by reference
1347                 $outputPage = $this;
1348                 # Add the remaining categories to the skin
1349                 if ( Hooks::run(
1350                         'OutputPageMakeCategoryLinks',
1351                         [ &$outputPage, $categories, &$this->mCategoryLinks ] )
1352                 ) {
1353                         $services = MediaWikiServices::getInstance();
1354                         $linkRenderer = $services->getLinkRenderer();
1355                         foreach ( $categories as $category => $type ) {
1356                                 // array keys will cast numeric category names to ints, so cast back to string
1357                                 $category = (string)$category;
1358                                 $origcategory = $category;
1359                                 $title = Title::makeTitleSafe( NS_CATEGORY, $category );
1360                                 if ( !$title ) {
1361                                         continue;
1362                                 }
1363                                 $services->getContentLanguage()->findVariantLink( $category, $title, true );
1364                                 if ( $category != $origcategory && array_key_exists( $category, $categories ) ) {
1365                                         continue;
1366                                 }
1367                                 $text = $services->getContentLanguage()->convertHtml( $title->getText() );
1368                                 $this->mCategories[$type][] = $title->getText();
1369                                 $this->mCategoryLinks[$type][] = $linkRenderer->makeLink( $title, new HtmlArmor( $text ) );
1370                         }
1371                 }
1372         }
1373
1374         /**
1375          * @param array $categories
1376          * @return bool|IResultWrapper
1377          */
1378         protected function addCategoryLinksToLBAndGetResult( array $categories ) {
1379                 # Add the links to a LinkBatch
1380                 $arr = [ NS_CATEGORY => $categories ];
1381                 $lb = new LinkBatch;
1382                 $lb->setArray( $arr );
1383
1384                 # Fetch existence plus the hiddencat property
1385                 $dbr = wfGetDB( DB_REPLICA );
1386                 $fields = array_merge(
1387                         LinkCache::getSelectFields(),
1388                         [ 'page_namespace', 'page_title', 'pp_value' ]
1389                 );
1390
1391                 $res = $dbr->select( [ 'page', 'page_props' ],
1392                         $fields,
1393                         $lb->constructSet( 'page', $dbr ),
1394                         __METHOD__,
1395                         [],
1396                         [ 'page_props' => [ 'LEFT JOIN', [
1397                                 'pp_propname' => 'hiddencat',
1398                                 'pp_page = page_id'
1399                         ] ] ]
1400                 );
1401
1402                 # Add the results to the link cache
1403                 $linkCache = MediaWikiServices::getInstance()->getLinkCache();
1404                 $lb->addResultToCache( $linkCache, $res );
1405
1406                 return $res;
1407         }
1408
1409         /**
1410          * Reset the category links (but not the category list) and add $categories
1411          *
1412          * @param array $categories Mapping category name => sort key
1413          */
1414         public function setCategoryLinks( array $categories ) {
1415                 $this->mCategoryLinks = [];
1416                 $this->addCategoryLinks( $categories );
1417         }
1418
1419         /**
1420          * Get the list of category links, in a 2-D array with the following format:
1421          * $arr[$type][] = $link, where $type is either "normal" or "hidden" (for
1422          * hidden categories) and $link a HTML fragment with a link to the category
1423          * page
1424          *
1425          * @return array
1426          */
1427         public function getCategoryLinks() {
1428                 return $this->mCategoryLinks;
1429         }
1430
1431         /**
1432          * Get the list of category names this page belongs to.
1433          *
1434          * @param string $type The type of categories which should be returned. Possible values:
1435          *  * all: all categories of all types
1436          *  * hidden: only the hidden categories
1437          *  * normal: all categories, except hidden categories
1438          * @return array Array of strings
1439          */
1440         public function getCategories( $type = 'all' ) {
1441                 if ( $type === 'all' ) {
1442                         $allCategories = [];
1443                         foreach ( $this->mCategories as $categories ) {
1444                                 $allCategories = array_merge( $allCategories, $categories );
1445                         }
1446                         return $allCategories;
1447                 }
1448                 if ( !isset( $this->mCategories[$type] ) ) {
1449                         throw new InvalidArgumentException( 'Invalid category type given: ' . $type );
1450                 }
1451                 return $this->mCategories[$type];
1452         }
1453
1454         /**
1455          * Add an array of indicators, with their identifiers as array
1456          * keys and HTML contents as values.
1457          *
1458          * In case of duplicate keys, existing values are overwritten.
1459          *
1460          * @param array $indicators
1461          * @since 1.25
1462          */
1463         public function setIndicators( array $indicators ) {
1464                 $this->mIndicators = $indicators + $this->mIndicators;
1465                 // Keep ordered by key
1466                 ksort( $this->mIndicators );
1467         }
1468
1469         /**
1470          * Get the indicators associated with this page.
1471          *
1472          * The array will be internally ordered by item keys.
1473          *
1474          * @return array Keys: identifiers, values: HTML contents
1475          * @since 1.25
1476          */
1477         public function getIndicators() {
1478                 return $this->mIndicators;
1479         }
1480
1481         /**
1482          * Adds help link with an icon via page indicators.
1483          * Link target can be overridden by a local message containing a wikilink:
1484          * the message key is: lowercase action or special page name + '-helppage'.
1485          * @param string $to Target MediaWiki.org page title or encoded URL.
1486          * @param bool $overrideBaseUrl Whether $url is a full URL, to avoid MW.o.
1487          * @since 1.25
1488          */
1489         public function addHelpLink( $to, $overrideBaseUrl = false ) {
1490                 $this->addModuleStyles( 'mediawiki.helplink' );
1491                 $text = $this->msg( 'helppage-top-gethelp' )->escaped();
1492
1493                 if ( $overrideBaseUrl ) {
1494                         $helpUrl = $to;
1495                 } else {
1496                         $toUrlencoded = wfUrlencode( str_replace( ' ', '_', $to ) );
1497                         $helpUrl = "//www.mediawiki.org/wiki/Special:MyLanguage/$toUrlencoded";
1498                 }
1499
1500                 $link = Html::rawElement(
1501                         'a',
1502                         [
1503                                 'href' => $helpUrl,
1504                                 'target' => '_blank',
1505                                 'class' => 'mw-helplink',
1506                         ],
1507                         $text
1508                 );
1509
1510                 $this->setIndicators( [ 'mw-helplink' => $link ] );
1511         }
1512
1513         /**
1514          * Do not allow scripts which can be modified by wiki users to load on this page;
1515          * only allow scripts bundled with, or generated by, the software.
1516          * Site-wide styles are controlled by a config setting, since they can be
1517          * used to create a custom skin/theme, but not user-specific ones.
1518          *
1519          * @todo this should be given a more accurate name
1520          */
1521         public function disallowUserJs() {
1522                 $this->reduceAllowedModules(
1523                         ResourceLoaderModule::TYPE_SCRIPTS,
1524                         ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
1525                 );
1526
1527                 // Site-wide styles are controlled by a config setting, see T73621
1528                 // for background on why. User styles are never allowed.
1529                 if ( $this->getConfig()->get( 'AllowSiteCSSOnRestrictedPages' ) ) {
1530                         $styleOrigin = ResourceLoaderModule::ORIGIN_USER_SITEWIDE;
1531                 } else {
1532                         $styleOrigin = ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL;
1533                 }
1534                 $this->reduceAllowedModules(
1535                         ResourceLoaderModule::TYPE_STYLES,
1536                         $styleOrigin
1537                 );
1538         }
1539
1540         /**
1541          * Show what level of JavaScript / CSS untrustworthiness is allowed on this page
1542          * @see ResourceLoaderModule::$origin
1543          * @param string $type ResourceLoaderModule TYPE_ constant
1544          * @return int ResourceLoaderModule ORIGIN_ class constant
1545          */
1546         public function getAllowedModules( $type ) {
1547                 if ( $type == ResourceLoaderModule::TYPE_COMBINED ) {
1548                         return min( array_values( $this->mAllowedModules ) );
1549                 } else {
1550                         return $this->mAllowedModules[$type] ?? ResourceLoaderModule::ORIGIN_ALL;
1551                 }
1552         }
1553
1554         /**
1555          * Limit the highest level of CSS/JS untrustworthiness allowed.
1556          *
1557          * If passed the same or a higher level than the current level of untrustworthiness set, the
1558          * level will remain unchanged.
1559          *
1560          * @param string $type
1561          * @param int $level ResourceLoaderModule class constant
1562          */
1563         public function reduceAllowedModules( $type, $level ) {
1564                 $this->mAllowedModules[$type] = min( $this->getAllowedModules( $type ), $level );
1565         }
1566
1567         /**
1568          * Prepend $text to the body HTML
1569          *
1570          * @param string $text HTML
1571          */
1572         public function prependHTML( $text ) {
1573                 $this->mBodytext = $text . $this->mBodytext;
1574         }
1575
1576         /**
1577          * Append $text to the body HTML
1578          *
1579          * @param string $text HTML
1580          */
1581         public function addHTML( $text ) {
1582                 $this->mBodytext .= $text;
1583         }
1584
1585         /**
1586          * Shortcut for adding an Html::element via addHTML.
1587          *
1588          * @since 1.19
1589          *
1590          * @param string $element
1591          * @param array $attribs
1592          * @param string $contents
1593          */
1594         public function addElement( $element, array $attribs = [], $contents = '' ) {
1595                 $this->addHTML( Html::element( $element, $attribs, $contents ) );
1596         }
1597
1598         /**
1599          * Clear the body HTML
1600          */
1601         public function clearHTML() {
1602                 $this->mBodytext = '';
1603         }
1604
1605         /**
1606          * Get the body HTML
1607          *
1608          * @return string HTML
1609          */
1610         public function getHTML() {
1611                 return $this->mBodytext;
1612         }
1613
1614         /**
1615          * Get/set the ParserOptions object to use for wikitext parsing
1616          *
1617          * @param ParserOptions|null $options Either the ParserOption to use or null to only get the
1618          *   current ParserOption object. This parameter is deprecated since 1.31.
1619          * @return ParserOptions
1620          */
1621         public function parserOptions( $options = null ) {
1622                 if ( $options !== null ) {
1623                         wfDeprecated( __METHOD__ . ' with non-null $options', '1.31' );
1624                 }
1625
1626                 if ( $options !== null && !empty( $options->isBogus ) ) {
1627                         // Someone is trying to set a bogus pre-$wgUser PO. Check if it has
1628                         // been changed somehow, and keep it if so.
1629                         $anonPO = ParserOptions::newFromAnon();
1630                         $anonPO->setAllowUnsafeRawHtml( false );
1631                         if ( !$options->matches( $anonPO ) ) {
1632                                 wfLogWarning( __METHOD__ . ': Setting a changed bogus ParserOptions: ' . wfGetAllCallers( 5 ) );
1633                                 $options->isBogus = false;
1634                         }
1635                 }
1636
1637                 if ( !$this->mParserOptions ) {
1638                         if ( !$this->getContext()->getUser()->isSafeToLoad() ) {
1639                                 // $wgUser isn't unstubbable yet, so don't try to get a
1640                                 // ParserOptions for it. And don't cache this ParserOptions
1641                                 // either.
1642                                 $po = ParserOptions::newFromAnon();
1643                                 $po->setAllowUnsafeRawHtml( false );
1644                                 $po->isBogus = true;
1645                                 if ( $options !== null ) {
1646                                         $this->mParserOptions = empty( $options->isBogus ) ? $options : null;
1647                                 }
1648                                 return $po;
1649                         }
1650
1651                         $this->mParserOptions = ParserOptions::newFromContext( $this->getContext() );
1652                         $this->mParserOptions->setAllowUnsafeRawHtml( false );
1653                 }
1654
1655                 if ( $options !== null && !empty( $options->isBogus ) ) {
1656                         // They're trying to restore the bogus pre-$wgUser PO. Do the right
1657                         // thing.
1658                         return wfSetVar( $this->mParserOptions, null, true );
1659                 } else {
1660                         return wfSetVar( $this->mParserOptions, $options );
1661                 }
1662         }
1663
1664         /**
1665          * Set the revision ID which will be seen by the wiki text parser
1666          * for things such as embedded {{REVISIONID}} variable use.
1667          *
1668          * @param int|null $revid A positive integer, or null
1669          * @return mixed Previous value
1670          */
1671         public function setRevisionId( $revid ) {
1672                 $val = is_null( $revid ) ? null : intval( $revid );
1673                 return wfSetVar( $this->mRevisionId, $val, true );
1674         }
1675
1676         /**
1677          * Get the displayed revision ID
1678          *
1679          * @return int
1680          */
1681         public function getRevisionId() {
1682                 return $this->mRevisionId;
1683         }
1684
1685         /**
1686          * Set the timestamp of the revision which will be displayed. This is used
1687          * to avoid a extra DB call in Skin::lastModified().
1688          *
1689          * @param string|null $timestamp
1690          * @return mixed Previous value
1691          */
1692         public function setRevisionTimestamp( $timestamp ) {
1693                 return wfSetVar( $this->mRevisionTimestamp, $timestamp, true );
1694         }
1695
1696         /**
1697          * Get the timestamp of displayed revision.
1698          * This will be null if not filled by setRevisionTimestamp().
1699          *
1700          * @return string|null
1701          */
1702         public function getRevisionTimestamp() {
1703                 return $this->mRevisionTimestamp;
1704         }
1705
1706         /**
1707          * Set the displayed file version
1708          *
1709          * @param File|null $file
1710          * @return mixed Previous value
1711          */
1712         public function setFileVersion( $file ) {
1713                 $val = null;
1714                 if ( $file instanceof File && $file->exists() ) {
1715                         $val = [ 'time' => $file->getTimestamp(), 'sha1' => $file->getSha1() ];
1716                 }
1717                 return wfSetVar( $this->mFileVersion, $val, true );
1718         }
1719
1720         /**
1721          * Get the displayed file version
1722          *
1723          * @return array|null ('time' => MW timestamp, 'sha1' => sha1)
1724          */
1725         public function getFileVersion() {
1726                 return $this->mFileVersion;
1727         }
1728
1729         /**
1730          * Get the templates used on this page
1731          *
1732          * @return array (namespace => dbKey => revId)
1733          * @since 1.18
1734          */
1735         public function getTemplateIds() {
1736                 return $this->mTemplateIds;
1737         }
1738
1739         /**
1740          * Get the files used on this page
1741          *
1742          * @return array (dbKey => array('time' => MW timestamp or null, 'sha1' => sha1 or ''))
1743          * @since 1.18
1744          */
1745         public function getFileSearchOptions() {
1746                 return $this->mImageTimeKeys;
1747         }
1748
1749         /**
1750          * Convert wikitext to HTML and add it to the buffer
1751          * Default assumes that the current page title will be used.
1752          *
1753          * @param string $text
1754          * @param bool $linestart Is this the start of a line?
1755          * @param bool $interface Is this text in the user interface language?
1756          * @throws MWException
1757          * @deprecated since 1.32 due to untidy output; use
1758          *    addWikiTextAsInterface() if $interface is default value or true,
1759          *    or else addWikiTextAsContent() if $interface is false.
1760          */
1761         public function addWikiText( $text, $linestart = true, $interface = true ) {
1762                 wfDeprecated( __METHOD__, '1.32' );
1763                 $title = $this->getTitle();
1764                 if ( !$title ) {
1765                         throw new MWException( 'Title is null' );
1766                 }
1767                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/false, $interface );
1768         }
1769
1770         /**
1771          * Convert wikitext *in the user interface language* to HTML and
1772          * add it to the buffer. The result will not be
1773          * language-converted, as user interface messages are already
1774          * localized into a specific variant.  Assumes that the current
1775          * page title will be used if optional $title is not
1776          * provided. Output will be tidy.
1777          *
1778          * @param string $text Wikitext in the user interface language
1779          * @param bool $linestart Is this the start of a line? (Defaults to true)
1780          * @param Title|null $title Optional title to use; default of `null`
1781          *   means use current page title.
1782          * @throws MWException if $title is not provided and OutputPage::getTitle()
1783          *   is null
1784          * @since 1.32
1785          */
1786         public function addWikiTextAsInterface(
1787                 $text, $linestart = true, Title $title = null
1788         ) {
1789                 if ( $title === null ) {
1790                         $title = $this->getTitle();
1791                 }
1792                 if ( !$title ) {
1793                         throw new MWException( 'Title is null' );
1794                 }
1795                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/true, /*interface*/true );
1796         }
1797
1798         /**
1799          * Convert wikitext *in the user interface language* to HTML and
1800          * add it to the buffer with a `<div class="$wrapperClass">`
1801          * wrapper.  The result will not be language-converted, as user
1802          * interface messages as already localized into a specific
1803          * variant.  The $text will be parsed in start-of-line context.
1804          * Output will be tidy.
1805          *
1806          * @param string $wrapperClass The class attribute value for the <div>
1807          *   wrapper in the output HTML
1808          * @param string $text Wikitext in the user interface language
1809          * @since 1.32
1810          */
1811         public function wrapWikiTextAsInterface(
1812                 $wrapperClass, $text
1813         ) {
1814                 $this->addWikiTextTitleInternal(
1815                         $text, $this->getTitle(),
1816                         /*linestart*/true, /*tidy*/true, /*interface*/true,
1817                         $wrapperClass
1818                 );
1819         }
1820
1821         /**
1822          * Convert wikitext *in the page content language* to HTML and add
1823          * it to the buffer.  The result with be language-converted to the
1824          * user's preferred variant.  Assumes that the current page title
1825          * will be used if optional $title is not provided. Output will be
1826          * tidy.
1827          *
1828          * @param string $text Wikitext in the page content language
1829          * @param bool $linestart Is this the start of a line? (Defaults to true)
1830          * @param Title|null $title Optional title to use; default of `null`
1831          *   means use current page title.
1832          * @throws MWException if $title is not provided and OutputPage::getTitle()
1833          *   is null
1834          * @since 1.32
1835          */
1836         public function addWikiTextAsContent(
1837                 $text, $linestart = true, Title $title = null
1838         ) {
1839                 if ( $title === null ) {
1840                         $title = $this->getTitle();
1841                 }
1842                 if ( !$title ) {
1843                         throw new MWException( 'Title is null' );
1844                 }
1845                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/true, /*interface*/false );
1846         }
1847
1848         /**
1849          * Add wikitext with a custom Title object
1850          *
1851          * @param string $text Wikitext
1852          * @param Title $title
1853          * @param bool $linestart Is this the start of a line?
1854          * @deprecated since 1.32 due to untidy output; use
1855          *   addWikiTextAsInterface()
1856          */
1857         public function addWikiTextWithTitle( $text, Title $title, $linestart = true ) {
1858                 wfDeprecated( __METHOD__, '1.32' );
1859                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/false, /*interface*/false );
1860         }
1861
1862         /**
1863          * Add wikitext *in content language* with a custom Title object.
1864          * Output will be tidy.
1865          *
1866          * @param string $text Wikitext in content language
1867          * @param Title $title
1868          * @param bool $linestart Is this the start of a line?
1869          * @deprecated since 1.32 to rename methods consistently; use
1870          *   addWikiTextAsContent()
1871          */
1872         function addWikiTextTitleTidy( $text, Title $title, $linestart = true ) {
1873                 wfDeprecated( __METHOD__, '1.32' );
1874                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/true, /*interface*/false );
1875         }
1876
1877         /**
1878          * Add wikitext *in content language*. Output will be tidy.
1879          *
1880          * @param string $text Wikitext in content language
1881          * @param bool $linestart Is this the start of a line?
1882          * @deprecated since 1.32 to rename methods consistently; use
1883          *   addWikiTextAsContent()
1884          */
1885         public function addWikiTextTidy( $text, $linestart = true ) {
1886                 wfDeprecated( __METHOD__, '1.32' );
1887                 $title = $this->getTitle();
1888                 if ( !$title ) {
1889                         throw new MWException( 'Title is null' );
1890                 }
1891                 $this->addWikiTextTitleInternal( $text, $title, $linestart, /*tidy*/true, /*interface*/false );
1892         }
1893
1894         /**
1895          * Add wikitext with a custom Title object.
1896          * Output is unwrapped.
1897          *
1898          * @param string $text Wikitext
1899          * @param Title $title
1900          * @param bool $linestart Is this the start of a line?
1901          * @param bool $tidy Whether to use tidy.
1902          *             Setting this to false (or omitting it) is deprecated
1903          *             since 1.32; all wikitext should be tidied.
1904          *             For backwards-compatibility with prior MW releases,
1905          *             you may wish to invoke this method but set $tidy=true;
1906          *             this will result in equivalent output to the non-deprecated
1907          *             addWikiTextAsContent()/addWikiTextAsInterface() methods.
1908          * @param bool $interface Whether it is an interface message
1909          *   (for example disables conversion)
1910          * @deprecated since 1.32, use addWikiTextAsContent() or
1911          *   addWikiTextAsInterface() (depending on $interface)
1912          */
1913         public function addWikiTextTitle( $text, Title $title, $linestart,
1914                 $tidy = false, $interface = false
1915         ) {
1916                 wfDeprecated( __METHOD__, '1.32' );
1917                 return $this->addWikiTextTitleInternal( $text, $title, $linestart, $tidy, $interface );
1918         }
1919
1920         /**
1921          * Add wikitext with a custom Title object.
1922          * Output is unwrapped.
1923          *
1924          * @param string $text Wikitext
1925          * @param Title $title
1926          * @param bool $linestart Is this the start of a line?
1927          * @param bool $tidy Whether to use tidy.
1928          *             Setting this to false (or omitting it) is deprecated
1929          *             since 1.32; all wikitext should be tidied.
1930          * @param bool $interface Whether it is an interface message
1931          *   (for example disables conversion)
1932          * @param string $wrapperClass if not empty, wraps the output in
1933          *   a `<div class="$wrapperClass">`
1934          * @private
1935          */
1936         private function addWikiTextTitleInternal(
1937                 $text, Title $title, $linestart, $tidy, $interface, $wrapperClass = null
1938         ) {
1939                 if ( !$tidy ) {
1940                         wfDeprecated( 'disabling tidy', '1.32' );
1941                 }
1942
1943                 $parserOutput = $this->parseInternal(
1944                         $text, $title, $linestart, $tidy, $interface, /*language*/null
1945                 );
1946
1947                 $this->addParserOutput( $parserOutput, [
1948                         'enableSectionEditLinks' => false,
1949                         'wrapperDivClass' => $wrapperClass ?? '',
1950                 ] );
1951         }
1952
1953         /**
1954          * Add all metadata associated with a ParserOutput object, but without the actual HTML. This
1955          * includes categories, language links, ResourceLoader modules, effects of certain magic words,
1956          * and so on.
1957          *
1958          * @since 1.24
1959          * @param ParserOutput $parserOutput
1960          */
1961         public function addParserOutputMetadata( ParserOutput $parserOutput ) {
1962                 $this->mLanguageLinks =
1963                         array_merge( $this->mLanguageLinks, $parserOutput->getLanguageLinks() );
1964                 $this->addCategoryLinks( $parserOutput->getCategories() );
1965                 $this->setIndicators( $parserOutput->getIndicators() );
1966                 $this->mNewSectionLink = $parserOutput->getNewSection();
1967                 $this->mHideNewSectionLink = $parserOutput->getHideNewSection();
1968
1969                 if ( !$parserOutput->isCacheable() ) {
1970                         $this->enableClientCache( false );
1971                 }
1972                 $this->mNoGallery = $parserOutput->getNoGallery();
1973                 $this->mHeadItems = array_merge( $this->mHeadItems, $parserOutput->getHeadItems() );
1974                 $this->addModules( $parserOutput->getModules() );
1975                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1976                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1977                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1978                 $this->mPreventClickjacking = $this->mPreventClickjacking
1979                         || $parserOutput->preventClickjacking();
1980
1981                 // Template versioning...
1982                 foreach ( (array)$parserOutput->getTemplateIds() as $ns => $dbks ) {
1983                         if ( isset( $this->mTemplateIds[$ns] ) ) {
1984                                 $this->mTemplateIds[$ns] = $dbks + $this->mTemplateIds[$ns];
1985                         } else {
1986                                 $this->mTemplateIds[$ns] = $dbks;
1987                         }
1988                 }
1989                 // File versioning...
1990                 foreach ( (array)$parserOutput->getFileSearchOptions() as $dbk => $data ) {
1991                         $this->mImageTimeKeys[$dbk] = $data;
1992                 }
1993
1994                 // Hooks registered in the object
1995                 $parserOutputHooks = $this->getConfig()->get( 'ParserOutputHooks' );
1996                 foreach ( $parserOutput->getOutputHooks() as $hookInfo ) {
1997                         list( $hookName, $data ) = $hookInfo;
1998                         if ( isset( $parserOutputHooks[$hookName] ) ) {
1999                                 $parserOutputHooks[$hookName]( $this, $parserOutput, $data );
2000                         }
2001                 }
2002
2003                 // Enable OOUI if requested via ParserOutput
2004                 if ( $parserOutput->getEnableOOUI() ) {
2005                         $this->enableOOUI();
2006                 }
2007
2008                 // Include parser limit report
2009                 if ( !$this->limitReportJSData ) {
2010                         $this->limitReportJSData = $parserOutput->getLimitReportJSData();
2011                 }
2012
2013                 // Link flags are ignored for now, but may in the future be
2014                 // used to mark individual language links.
2015                 $linkFlags = [];
2016                 // Avoid PHP 7.1 warning of passing $this by reference
2017                 $outputPage = $this;
2018                 Hooks::run( 'LanguageLinks', [ $this->getTitle(), &$this->mLanguageLinks, &$linkFlags ] );
2019                 Hooks::runWithoutAbort( 'OutputPageParserOutput', [ &$outputPage, $parserOutput ] );
2020
2021                 // This check must be after 'OutputPageParserOutput' runs in addParserOutputMetadata
2022                 // so that extensions may modify ParserOutput to toggle TOC.
2023                 // This cannot be moved to addParserOutputText because that is not
2024                 // called by EditPage for Preview.
2025                 if ( $parserOutput->getTOCHTML() ) {
2026                         $this->mEnableTOC = true;
2027                 }
2028         }
2029
2030         /**
2031          * Add the HTML and enhancements for it (like ResourceLoader modules) associated with a
2032          * ParserOutput object, without any other metadata.
2033          *
2034          * @since 1.24
2035          * @param ParserOutput $parserOutput
2036          * @param array $poOptions Options to ParserOutput::getText()
2037          */
2038         public function addParserOutputContent( ParserOutput $parserOutput, $poOptions = [] ) {
2039                 $this->addParserOutputText( $parserOutput, $poOptions );
2040
2041                 $this->addModules( $parserOutput->getModules() );
2042                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
2043                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
2044
2045                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
2046         }
2047
2048         /**
2049          * Add the HTML associated with a ParserOutput object, without any metadata.
2050          *
2051          * @since 1.24
2052          * @param ParserOutput $parserOutput
2053          * @param array $poOptions Options to ParserOutput::getText()
2054          */
2055         public function addParserOutputText( ParserOutput $parserOutput, $poOptions = [] ) {
2056                 $text = $parserOutput->getText( $poOptions );
2057                 // Avoid PHP 7.1 warning of passing $this by reference
2058                 $outputPage = $this;
2059                 Hooks::runWithoutAbort( 'OutputPageBeforeHTML', [ &$outputPage, &$text ] );
2060                 $this->addHTML( $text );
2061         }
2062
2063         /**
2064          * Add everything from a ParserOutput object.
2065          *
2066          * @param ParserOutput $parserOutput
2067          * @param array $poOptions Options to ParserOutput::getText()
2068          */
2069         function addParserOutput( ParserOutput $parserOutput, $poOptions = [] ) {
2070                 $this->addParserOutputMetadata( $parserOutput );
2071                 $this->addParserOutputText( $parserOutput, $poOptions );
2072         }
2073
2074         /**
2075          * Add the output of a QuickTemplate to the output buffer
2076          *
2077          * @param QuickTemplate &$template
2078          */
2079         public function addTemplate( &$template ) {
2080                 $this->addHTML( $template->getHTML() );
2081         }
2082
2083         /**
2084          * Parse wikitext and return the HTML.
2085          *
2086          * @todo The output is wrapped in a <div> iff $interface is false; it's
2087          * probably best to always strip the wrapper.
2088          *
2089          * @param string $text
2090          * @param bool $linestart Is this the start of a line?
2091          * @param bool $interface Use interface language (instead of content language) while parsing
2092          *   language sensitive magic words like GRAMMAR and PLURAL.  This also disables
2093          *   LanguageConverter.
2094          * @param Language|null $language Target language object, will override $interface
2095          * @throws MWException
2096          * @return string HTML
2097          * @deprecated since 1.32, due to untidy output and inconsistent wrapper;
2098          *  use parseAsContent() if $interface is default value or false, or else
2099          *  parseAsInterface() if $interface is true.
2100          */
2101         public function parse( $text, $linestart = true, $interface = false, $language = null ) {
2102                 wfDeprecated( __METHOD__, '1.33' );
2103                 return $this->parseInternal(
2104                         $text, $this->getTitle(), $linestart, /*tidy*/false, $interface, $language
2105                 )->getText( [
2106                         'enableSectionEditLinks' => false,
2107                 ] );
2108         }
2109
2110         /**
2111          * Parse wikitext *in the page content language* and return the HTML.
2112          * The result will be language-converted to the user's preferred variant.
2113          * Output will be tidy.
2114          *
2115          * @param string $text Wikitext in the page content language
2116          * @param bool $linestart Is this the start of a line? (Defaults to true)
2117          * @throws MWException
2118          * @return string HTML
2119          * @since 1.32
2120          */
2121         public function parseAsContent( $text, $linestart = true ) {
2122                 return $this->parseInternal(
2123                         $text, $this->getTitle(), $linestart, /*tidy*/true, /*interface*/false, /*language*/null
2124                 )->getText( [
2125                         'enableSectionEditLinks' => false,
2126                         'wrapperDivClass' => ''
2127                 ] );
2128         }
2129
2130         /**
2131          * Parse wikitext *in the user interface language* and return the HTML.
2132          * The result will not be language-converted, as user interface messages
2133          * are already localized into a specific variant.
2134          * Output will be tidy.
2135          *
2136          * @param string $text Wikitext in the user interface language
2137          * @param bool $linestart Is this the start of a line? (Defaults to true)
2138          * @throws MWException
2139          * @return string HTML
2140          * @since 1.32
2141          */
2142         public function parseAsInterface( $text, $linestart = true ) {
2143                 return $this->parseInternal(
2144                         $text, $this->getTitle(), $linestart, /*tidy*/true, /*interface*/true, /*language*/null
2145                 )->getText( [
2146                         'enableSectionEditLinks' => false,
2147                         'wrapperDivClass' => ''
2148                 ] );
2149         }
2150
2151         /**
2152          * Parse wikitext *in the user interface language*, strip
2153          * paragraph wrapper, and return the HTML.
2154          * The result will not be language-converted, as user interface messages
2155          * are already localized into a specific variant.
2156          * Output will be tidy.  Outer paragraph wrapper will only be stripped
2157          * if the result is a single paragraph.
2158          *
2159          * @param string $text Wikitext in the user interface language
2160          * @param bool $linestart Is this the start of a line? (Defaults to true)
2161          * @throws MWException
2162          * @return string HTML
2163          * @since 1.32
2164          */
2165         public function parseInlineAsInterface( $text, $linestart = true ) {
2166                 return Parser::stripOuterParagraph(
2167                         $this->parseAsInterface( $text, $linestart )
2168                 );
2169         }
2170
2171         /**
2172          * Parse wikitext, strip paragraph wrapper, and return the HTML.
2173          *
2174          * @param string $text
2175          * @param bool $linestart Is this the start of a line?
2176          * @param bool $interface Use interface language (instead of content language) while parsing
2177          *   language sensitive magic words like GRAMMAR and PLURAL
2178          * @return string HTML
2179          * @deprecated since 1.32, due to untidy output and confusing default
2180          *   for $interface.  Use parseInlineAsInterface() if $interface is
2181          *   the default value or false, or else use
2182          *   Parser::stripOuterParagraph($outputPage->parseAsContent(...)).
2183          */
2184         public function parseInline( $text, $linestart = true, $interface = false ) {
2185                 wfDeprecated( __METHOD__, '1.33' );
2186                 $parsed = $this->parseInternal(
2187                         $text, $this->getTitle(), $linestart, /*tidy*/false, $interface, /*language*/null
2188                 )->getText( [
2189                         'enableSectionEditLinks' => false,
2190                         'wrapperDivClass' => '', /* no wrapper div */
2191                 ] );
2192                 return Parser::stripOuterParagraph( $parsed );
2193         }
2194
2195         /**
2196          * Parse wikitext and return the HTML (internal implementation helper)
2197          *
2198          * @param string $text
2199          * @param Title The title to use
2200          * @param bool $linestart Is this the start of a line?
2201          * @param bool $tidy Whether the output should be tidied
2202          * @param bool $interface Use interface language (instead of content language) while parsing
2203          *   language sensitive magic words like GRAMMAR and PLURAL.  This also disables
2204          *   LanguageConverter.
2205          * @param Language|null $language Target language object, will override $interface
2206          * @throws MWException
2207          * @return ParserOutput
2208          */
2209         private function parseInternal( $text, $title, $linestart, $tidy, $interface, $language ) {
2210                 global $wgParser;
2211
2212                 if ( is_null( $title ) ) {
2213                         throw new MWException( 'Empty $mTitle in ' . __METHOD__ );
2214                 }
2215
2216                 $popts = $this->parserOptions();
2217                 $oldTidy = $popts->setTidy( $tidy );
2218                 $oldInterface = $popts->setInterfaceMessage( (bool)$interface );
2219
2220                 if ( $language !== null ) {
2221                         $oldLang = $popts->setTargetLanguage( $language );
2222                 }
2223
2224                 $parserOutput = $wgParser->getFreshParser()->parse(
2225                         $text, $title, $popts,
2226                         $linestart, true, $this->mRevisionId
2227                 );
2228
2229                 $popts->setTidy( $oldTidy );
2230                 $popts->setInterfaceMessage( $oldInterface );
2231
2232                 if ( $language !== null ) {
2233                         $popts->setTargetLanguage( $oldLang );
2234                 }
2235
2236                 return $parserOutput;
2237         }
2238
2239         /**
2240          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header
2241          *
2242          * @param int $maxage Maximum cache time on the CDN, in seconds.
2243          */
2244         public function setCdnMaxage( $maxage ) {
2245                 $this->mCdnMaxage = min( $maxage, $this->mCdnMaxageLimit );
2246         }
2247
2248         /**
2249          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header to $maxage if that is
2250          * lower than the current s-maxage.  Either way, $maxage is now an upper limit on s-maxage, so
2251          * that future calls to setCdnMaxage() will no longer be able to raise the s-maxage above
2252          * $maxage.
2253          *
2254          * @param int $maxage Maximum cache time on the CDN, in seconds
2255          * @since 1.27
2256          */
2257         public function lowerCdnMaxage( $maxage ) {
2258                 $this->mCdnMaxageLimit = min( $maxage, $this->mCdnMaxageLimit );
2259                 $this->setCdnMaxage( $this->mCdnMaxage );
2260         }
2261
2262         /**
2263          * Get TTL in [$minTTL,$maxTTL] in pass it to lowerCdnMaxage()
2264          *
2265          * This sets and returns $minTTL if $mtime is false or null. Otherwise,
2266          * the TTL is higher the older the $mtime timestamp is. Essentially, the
2267          * TTL is 90% of the age of the object, subject to the min and max.
2268          *
2269          * @param string|int|float|bool|null $mtime Last-Modified timestamp
2270          * @param int $minTTL Minimum TTL in seconds [default: 1 minute]
2271          * @param int $maxTTL Maximum TTL in seconds [default: $wgSquidMaxage]
2272          * @since 1.28
2273          */
2274         public function adaptCdnTTL( $mtime, $minTTL = 0, $maxTTL = 0 ) {
2275                 $minTTL = $minTTL ?: IExpiringStore::TTL_MINUTE;
2276                 $maxTTL = $maxTTL ?: $this->getConfig()->get( 'SquidMaxage' );
2277
2278                 if ( $mtime === null || $mtime === false ) {
2279                         return $minTTL; // entity does not exist
2280                 }
2281
2282                 $age = MWTimestamp::time() - wfTimestamp( TS_UNIX, $mtime );
2283                 $adaptiveTTL = max( 0.9 * $age, $minTTL );
2284                 $adaptiveTTL = min( $adaptiveTTL, $maxTTL );
2285
2286                 $this->lowerCdnMaxage( (int)$adaptiveTTL );
2287         }
2288
2289         /**
2290          * Use enableClientCache(false) to force it to send nocache headers
2291          *
2292          * @param bool|null $state New value, or null to not set the value
2293          *
2294          * @return bool Old value
2295          */
2296         public function enableClientCache( $state ) {
2297                 return wfSetVar( $this->mEnableClientCache, $state );
2298         }
2299
2300         /**
2301          * Get the list of cookie names that will influence the cache
2302          *
2303          * @return array
2304          */
2305         function getCacheVaryCookies() {
2306                 if ( self::$cacheVaryCookies === null ) {
2307                         $config = $this->getConfig();
2308                         self::$cacheVaryCookies = array_values( array_unique( array_merge(
2309                                 SessionManager::singleton()->getVaryCookies(),
2310                                 [
2311                                         'forceHTTPS',
2312                                 ],
2313                                 $config->get( 'CacheVaryCookies' )
2314                         ) ) );
2315                         Hooks::run( 'GetCacheVaryCookies', [ $this, &self::$cacheVaryCookies ] );
2316                 }
2317                 return self::$cacheVaryCookies;
2318         }
2319
2320         /**
2321          * Check if the request has a cache-varying cookie header
2322          * If it does, it's very important that we don't allow public caching
2323          *
2324          * @return bool
2325          */
2326         function haveCacheVaryCookies() {
2327                 $request = $this->getRequest();
2328                 foreach ( $this->getCacheVaryCookies() as $cookieName ) {
2329                         if ( $request->getCookie( $cookieName, '', '' ) !== '' ) {
2330                                 wfDebug( __METHOD__ . ": found $cookieName\n" );
2331                                 return true;
2332                         }
2333                 }
2334                 wfDebug( __METHOD__ . ": no cache-varying cookies found\n" );
2335                 return false;
2336         }
2337
2338         /**
2339          * Add an HTTP header that will influence on the cache
2340          *
2341          * @param string $header Header name
2342          * @param string[]|null $option Options for the Key header. See
2343          * https://datatracker.ietf.org/doc/draft-fielding-http-key/
2344          * for the list of valid options.
2345          */
2346         public function addVaryHeader( $header, array $option = null ) {
2347                 if ( !array_key_exists( $header, $this->mVaryHeader ) ) {
2348                         $this->mVaryHeader[$header] = [];
2349                 }
2350                 if ( !is_array( $option ) ) {
2351                         $option = [];
2352                 }
2353                 $this->mVaryHeader[$header] =
2354                         array_unique( array_merge( $this->mVaryHeader[$header], $option ) );
2355         }
2356
2357         /**
2358          * Return a Vary: header on which to vary caches. Based on the keys of $mVaryHeader,
2359          * such as Accept-Encoding or Cookie
2360          *
2361          * @return string
2362          */
2363         public function getVaryHeader() {
2364                 // If we vary on cookies, let's make sure it's always included here too.
2365                 if ( $this->getCacheVaryCookies() ) {
2366                         $this->addVaryHeader( 'Cookie' );
2367                 }
2368
2369                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2370                         $this->addVaryHeader( $header, $options );
2371                 }
2372                 return 'Vary: ' . implode( ', ', array_keys( $this->mVaryHeader ) );
2373         }
2374
2375         /**
2376          * Add an HTTP Link: header
2377          *
2378          * @param string $header Header value
2379          */
2380         public function addLinkHeader( $header ) {
2381                 $this->mLinkHeader[] = $header;
2382         }
2383
2384         /**
2385          * Return a Link: header. Based on the values of $mLinkHeader.
2386          *
2387          * @return string
2388          */
2389         public function getLinkHeader() {
2390                 if ( !$this->mLinkHeader ) {
2391                         return false;
2392                 }
2393
2394                 return 'Link: ' . implode( ',', $this->mLinkHeader );
2395         }
2396
2397         /**
2398          * Get a complete Key header
2399          *
2400          * @return string
2401          * @deprecated in 1.32; the IETF spec for this header expired w/o becoming
2402          *   a standard.
2403          */
2404         public function getKeyHeader() {
2405                 wfDeprecated( '$wgUseKeyHeader', '1.32' );
2406
2407                 $cvCookies = $this->getCacheVaryCookies();
2408
2409                 $cookiesOption = [];
2410                 foreach ( $cvCookies as $cookieName ) {
2411                         $cookiesOption[] = 'param=' . $cookieName;
2412                 }
2413                 $this->addVaryHeader( 'Cookie', $cookiesOption );
2414
2415                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2416                         $this->addVaryHeader( $header, $options );
2417                 }
2418
2419                 $headers = [];
2420                 foreach ( $this->mVaryHeader as $header => $option ) {
2421                         $newheader = $header;
2422                         if ( is_array( $option ) && count( $option ) > 0 ) {
2423                                 $newheader .= ';' . implode( ';', $option );
2424                         }
2425                         $headers[] = $newheader;
2426                 }
2427                 $key = 'Key: ' . implode( ',', $headers );
2428
2429                 return $key;
2430         }
2431
2432         /**
2433          * T23672: Add Accept-Language to Vary and Key headers if there's no 'variant' parameter in GET.
2434          *
2435          * For example:
2436          *   /w/index.php?title=Main_page will vary based on Accept-Language; but
2437          *   /w/index.php?title=Main_page&variant=zh-cn will not.
2438          */
2439         private function addAcceptLanguage() {
2440                 $title = $this->getTitle();
2441                 if ( !$title instanceof Title ) {
2442                         return;
2443                 }
2444
2445                 $lang = $title->getPageLanguage();
2446                 if ( !$this->getRequest()->getCheck( 'variant' ) && $lang->hasVariants() ) {
2447                         $variants = $lang->getVariants();
2448                         $aloption = [];
2449                         foreach ( $variants as $variant ) {
2450                                 if ( $variant === $lang->getCode() ) {
2451                                         continue;
2452                                 }
2453
2454                                 // XXX Note that this code is not strictly correct: we
2455                                 // do a case-insensitive match in
2456                                 // LanguageConverter::getHeaderVariant() while the
2457                                 // (abandoned, draft) spec for the `Key` header only
2458                                 // allows case-sensitive matches.  To match the logic
2459                                 // in LanguageConverter::getHeaderVariant() we should
2460                                 // also be looking at fallback variants and deprecated
2461                                 // mediawiki-internal codes, as well as BCP 47
2462                                 // normalized forms.
2463
2464                                 $aloption[] = "substr=$variant";
2465
2466                                 // IE and some other browsers use BCP 47 standards in their Accept-Language header,
2467                                 // like "zh-CN" or "zh-Hant".  We should handle these too.
2468                                 $variantBCP47 = LanguageCode::bcp47( $variant );
2469                                 if ( $variantBCP47 !== $variant ) {
2470                                         $aloption[] = "substr=$variantBCP47";
2471                                 }
2472                         }
2473                         $this->addVaryHeader( 'Accept-Language', $aloption );
2474                 }
2475         }
2476
2477         /**
2478          * Set a flag which will cause an X-Frame-Options header appropriate for
2479          * edit pages to be sent. The header value is controlled by
2480          * $wgEditPageFrameOptions.
2481          *
2482          * This is the default for special pages. If you display a CSRF-protected
2483          * form on an ordinary view page, then you need to call this function.
2484          *
2485          * @param bool $enable
2486          */
2487         public function preventClickjacking( $enable = true ) {
2488                 $this->mPreventClickjacking = $enable;
2489         }
2490
2491         /**
2492          * Turn off frame-breaking. Alias for $this->preventClickjacking(false).
2493          * This can be called from pages which do not contain any CSRF-protected
2494          * HTML form.
2495          */
2496         public function allowClickjacking() {
2497                 $this->mPreventClickjacking = false;
2498         }
2499
2500         /**
2501          * Get the prevent-clickjacking flag
2502          *
2503          * @since 1.24
2504          * @return bool
2505          */
2506         public function getPreventClickjacking() {
2507                 return $this->mPreventClickjacking;
2508         }
2509
2510         /**
2511          * Get the X-Frame-Options header value (without the name part), or false
2512          * if there isn't one. This is used by Skin to determine whether to enable
2513          * JavaScript frame-breaking, for clients that don't support X-Frame-Options.
2514          *
2515          * @return string|false
2516          */
2517         public function getFrameOptions() {
2518                 $config = $this->getConfig();
2519                 if ( $config->get( 'BreakFrames' ) ) {
2520                         return 'DENY';
2521                 } elseif ( $this->mPreventClickjacking && $config->get( 'EditPageFrameOptions' ) ) {
2522                         return $config->get( 'EditPageFrameOptions' );
2523                 }
2524                 return false;
2525         }
2526
2527         /**
2528          * Get the Origin-Trial header values. This is used to enable Chrome Origin
2529          * Trials: https://github.com/GoogleChrome/OriginTrials
2530          *
2531          * @return array
2532          */
2533         private function getOriginTrials() {
2534                 $config = $this->getConfig();
2535
2536                 return $config->get( 'OriginTrials' );
2537         }
2538
2539         /**
2540          * Send cache control HTTP headers
2541          */
2542         public function sendCacheControl() {
2543                 $response = $this->getRequest()->response();
2544                 $config = $this->getConfig();
2545
2546                 $this->addVaryHeader( 'Cookie' );
2547                 $this->addAcceptLanguage();
2548
2549                 # don't serve compressed data to clients who can't handle it
2550                 # maintain different caches for logged-in users and non-logged in ones
2551                 $response->header( $this->getVaryHeader() );
2552
2553                 if ( $config->get( 'UseKeyHeader' ) ) {
2554                         $response->header( $this->getKeyHeader() );
2555                 }
2556
2557                 if ( $this->mEnableClientCache ) {
2558                         if (
2559                                 $config->get( 'UseSquid' ) &&
2560                                 !$response->hasCookies() &&
2561                                 !SessionManager::getGlobalSession()->isPersistent() &&
2562                                 !$this->isPrintable() &&
2563                                 $this->mCdnMaxage != 0 &&
2564                                 !$this->haveCacheVaryCookies()
2565                         ) {
2566                                 if ( $config->get( 'UseESI' ) ) {
2567                                         wfDeprecated( '$wgUseESI = true', '1.33' );
2568                                         # We'll purge the proxy cache explicitly, but require end user agents
2569                                         # to revalidate against the proxy on each visit.
2570                                         # Surrogate-Control controls our CDN, Cache-Control downstream caches
2571                                         wfDebug( __METHOD__ .
2572                                                 ": proxy caching with ESI; {$this->mLastModified} **", 'private' );
2573                                         # start with a shorter timeout for initial testing
2574                                         # header( 'Surrogate-Control: max-age=2678400+2678400, content="ESI/1.0"');
2575                                         $response->header(
2576                                                 "Surrogate-Control: max-age={$config->get( 'SquidMaxage' )}" .
2577                                                 "+{$this->mCdnMaxage}, content=\"ESI/1.0\""
2578                                         );
2579                                         $response->header( 'Cache-Control: s-maxage=0, must-revalidate, max-age=0' );
2580                                 } else {
2581                                         # We'll purge the proxy cache for anons explicitly, but require end user agents
2582                                         # to revalidate against the proxy on each visit.
2583                                         # IMPORTANT! The CDN needs to replace the Cache-Control header with
2584                                         # Cache-Control: s-maxage=0, must-revalidate, max-age=0
2585                                         wfDebug( __METHOD__ .
2586                                                 ": local proxy caching; {$this->mLastModified} **", 'private' );
2587                                         # start with a shorter timeout for initial testing
2588                                         # header( "Cache-Control: s-maxage=2678400, must-revalidate, max-age=0" );
2589                                         $response->header( "Cache-Control: " .
2590                                                 "s-maxage={$this->mCdnMaxage}, must-revalidate, max-age=0" );
2591                                 }
2592                         } else {
2593                                 # We do want clients to cache if they can, but they *must* check for updates
2594                                 # on revisiting the page.
2595                                 wfDebug( __METHOD__ . ": private caching; {$this->mLastModified} **", 'private' );
2596                                 $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2597                                 $response->header( "Cache-Control: private, must-revalidate, max-age=0" );
2598                         }
2599                         if ( $this->mLastModified ) {
2600                                 $response->header( "Last-Modified: {$this->mLastModified}" );
2601                         }
2602                 } else {
2603                         wfDebug( __METHOD__ . ": no caching **", 'private' );
2604
2605                         # In general, the absence of a last modified header should be enough to prevent
2606                         # the client from using its cache. We send a few other things just to make sure.
2607                         $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2608                         $response->header( 'Cache-Control: no-cache, no-store, max-age=0, must-revalidate' );
2609                         $response->header( 'Pragma: no-cache' );
2610                 }
2611         }
2612
2613         /**
2614          * Transfer styles and JavaScript modules from skin.
2615          *
2616          * @param Skin $sk to load modules for
2617          */
2618         public function loadSkinModules( $sk ) {
2619                 foreach ( $sk->getDefaultModules() as $group => $modules ) {
2620                         if ( $group === 'styles' ) {
2621                                 foreach ( $modules as $key => $moduleMembers ) {
2622                                         $this->addModuleStyles( $moduleMembers );
2623                                 }
2624                         } else {
2625                                 $this->addModules( $modules );
2626                         }
2627                 }
2628         }
2629
2630         /**
2631          * Finally, all the text has been munged and accumulated into
2632          * the object, let's actually output it:
2633          *
2634          * @param bool $return Set to true to get the result as a string rather than sending it
2635          * @return string|null
2636          * @throws Exception
2637          * @throws FatalError
2638          * @throws MWException
2639          */
2640         public function output( $return = false ) {
2641                 if ( $this->mDoNothing ) {
2642                         return $return ? '' : null;
2643                 }
2644
2645                 $response = $this->getRequest()->response();
2646                 $config = $this->getConfig();
2647
2648                 if ( $this->mRedirect != '' ) {
2649                         # Standards require redirect URLs to be absolute
2650                         $this->mRedirect = wfExpandUrl( $this->mRedirect, PROTO_CURRENT );
2651
2652                         $redirect = $this->mRedirect;
2653                         $code = $this->mRedirectCode;
2654
2655                         if ( Hooks::run( "BeforePageRedirect", [ $this, &$redirect, &$code ] ) ) {
2656                                 if ( $code == '301' || $code == '303' ) {
2657                                         if ( !$config->get( 'DebugRedirects' ) ) {
2658                                                 $response->statusHeader( $code );
2659                                         }
2660                                         $this->mLastModified = wfTimestamp( TS_RFC2822 );
2661                                 }
2662                                 if ( $config->get( 'VaryOnXFP' ) ) {
2663                                         $this->addVaryHeader( 'X-Forwarded-Proto' );
2664                                 }
2665                                 $this->sendCacheControl();
2666
2667                                 $response->header( "Content-Type: text/html; charset=utf-8" );
2668                                 if ( $config->get( 'DebugRedirects' ) ) {
2669                                         $url = htmlspecialchars( $redirect );
2670                                         print "<!DOCTYPE html>\n<html>\n<head>\n<title>Redirect</title>\n</head>\n<body>\n";
2671                                         print "<p>Location: <a href=\"$url\">$url</a></p>\n";
2672                                         print "</body>\n</html>\n";
2673                                 } else {
2674                                         $response->header( 'Location: ' . $redirect );
2675                                 }
2676                         }
2677
2678                         return $return ? '' : null;
2679                 } elseif ( $this->mStatusCode ) {
2680                         $response->statusHeader( $this->mStatusCode );
2681                 }
2682
2683                 # Buffer output; final headers may depend on later processing
2684                 ob_start();
2685
2686                 $response->header( 'Content-type: ' . $config->get( 'MimeType' ) . '; charset=UTF-8' );
2687                 $response->header( 'Content-language: ' .
2688                         MediaWikiServices::getInstance()->getContentLanguage()->getHtmlCode() );
2689
2690                 if ( !$this->mArticleBodyOnly ) {
2691                         $sk = $this->getSkin();
2692                 }
2693
2694                 $linkHeader = $this->getLinkHeader();
2695                 if ( $linkHeader ) {
2696                         $response->header( $linkHeader );
2697                 }
2698
2699                 // Prevent framing, if requested
2700                 $frameOptions = $this->getFrameOptions();
2701                 if ( $frameOptions ) {
2702                         $response->header( "X-Frame-Options: $frameOptions" );
2703                 }
2704
2705                 $originTrials = $this->getOriginTrials();
2706                 foreach ( $originTrials as $originTrial ) {
2707                         $response->header( "Origin-Trial: $originTrial", false );
2708                 }
2709
2710                 ContentSecurityPolicy::sendHeaders( $this );
2711
2712                 if ( $this->mArticleBodyOnly ) {
2713                         echo $this->mBodytext;
2714                 } else {
2715                         // Enable safe mode if requested (T152169)
2716                         if ( $this->getRequest()->getBool( 'safemode' ) ) {
2717                                 $this->disallowUserJs();
2718                         }
2719
2720                         $sk = $this->getSkin();
2721                         $this->loadSkinModules( $sk );
2722
2723                         MWDebug::addModules( $this );
2724
2725                         // Avoid PHP 7.1 warning of passing $this by reference
2726                         $outputPage = $this;
2727                         // Hook that allows last minute changes to the output page, e.g.
2728                         // adding of CSS or Javascript by extensions.
2729                         Hooks::runWithoutAbort( 'BeforePageDisplay', [ &$outputPage, &$sk ] );
2730
2731                         try {
2732                                 $sk->outputPage();
2733                         } catch ( Exception $e ) {
2734                                 ob_end_clean(); // bug T129657
2735                                 throw $e;
2736                         }
2737                 }
2738
2739                 try {
2740                         // This hook allows last minute changes to final overall output by modifying output buffer
2741                         Hooks::runWithoutAbort( 'AfterFinalPageOutput', [ $this ] );
2742                 } catch ( Exception $e ) {
2743                         ob_end_clean(); // bug T129657
2744                         throw $e;
2745                 }
2746
2747                 $this->sendCacheControl();
2748
2749                 if ( $return ) {
2750                         return ob_get_clean();
2751                 } else {
2752                         ob_end_flush();
2753                         return null;
2754                 }
2755         }
2756
2757         /**
2758          * Prepare this object to display an error page; disable caching and
2759          * indexing, clear the current text and redirect, set the page's title
2760          * and optionally an custom HTML title (content of the "<title>" tag).
2761          *
2762          * @param string|Message $pageTitle Will be passed directly to setPageTitle()
2763          * @param string|Message $htmlTitle Will be passed directly to setHTMLTitle();
2764          *                   optional, if not passed the "<title>" attribute will be
2765          *                   based on $pageTitle
2766          */
2767         public function prepareErrorPage( $pageTitle, $htmlTitle = false ) {
2768                 $this->setPageTitle( $pageTitle );
2769                 if ( $htmlTitle !== false ) {
2770                         $this->setHTMLTitle( $htmlTitle );
2771                 }
2772                 $this->setRobotPolicy( 'noindex,nofollow' );
2773                 $this->setArticleRelated( false );
2774                 $this->enableClientCache( false );
2775                 $this->mRedirect = '';
2776                 $this->clearSubtitle();
2777                 $this->clearHTML();
2778         }
2779
2780         /**
2781          * Output a standard error page
2782          *
2783          * showErrorPage( 'titlemsg', 'pagetextmsg' );
2784          * showErrorPage( 'titlemsg', 'pagetextmsg', [ 'param1', 'param2' ] );
2785          * showErrorPage( 'titlemsg', $messageObject );
2786          * showErrorPage( $titleMessageObject, $messageObject );
2787          *
2788          * @param string|Message $title Message key (string) for page title, or a Message object
2789          * @param string|Message $msg Message key (string) for page text, or a Message object
2790          * @param array $params Message parameters; ignored if $msg is a Message object
2791          */
2792         public function showErrorPage( $title, $msg, $params = [] ) {
2793                 if ( !$title instanceof Message ) {
2794                         $title = $this->msg( $title );
2795                 }
2796
2797                 $this->prepareErrorPage( $title );
2798
2799                 if ( $msg instanceof Message ) {
2800                         if ( $params !== [] ) {
2801                                 trigger_error( 'Argument ignored: $params. The message parameters argument '
2802                                         . 'is discarded when the $msg argument is a Message object instead of '
2803                                         . 'a string.', E_USER_NOTICE );
2804                         }
2805                         $this->addHTML( $msg->parseAsBlock() );
2806                 } else {
2807                         $this->addWikiMsgArray( $msg, $params );
2808                 }
2809
2810                 $this->returnToMain();
2811         }
2812
2813         /**
2814          * Output a standard permission error page
2815          *
2816          * @param array $errors Error message keys or [key, param...] arrays
2817          * @param string|null $action Action that was denied or null if unknown
2818          */
2819         public function showPermissionsErrorPage( array $errors, $action = null ) {
2820                 foreach ( $errors as $key => $error ) {
2821                         $errors[$key] = (array)$error;
2822                 }
2823
2824                 // For some action (read, edit, create and upload), display a "login to do this action"
2825                 // error if all of the following conditions are met:
2826                 // 1. the user is not logged in
2827                 // 2. the only error is insufficient permissions (i.e. no block or something else)
2828                 // 3. the error can be avoided simply by logging in
2829                 if ( in_array( $action, [ 'read', 'edit', 'createpage', 'createtalk', 'upload' ] )
2830                         && $this->getUser()->isAnon() && count( $errors ) == 1 && isset( $errors[0][0] )
2831                         && ( $errors[0][0] == 'badaccess-groups' || $errors[0][0] == 'badaccess-group0' )
2832                         && ( User::groupHasPermission( 'user', $action )
2833                         || User::groupHasPermission( 'autoconfirmed', $action ) )
2834                 ) {
2835                         $displayReturnto = null;
2836
2837                         # Due to T34276, if a user does not have read permissions,
2838                         # $this->getTitle() will just give Special:Badtitle, which is
2839                         # not especially useful as a returnto parameter. Use the title
2840                         # from the request instead, if there was one.
2841                         $request = $this->getRequest();
2842                         $returnto = Title::newFromText( $request->getVal( 'title', '' ) );
2843                         if ( $action == 'edit' ) {
2844                                 $msg = 'whitelistedittext';
2845                                 $displayReturnto = $returnto;
2846                         } elseif ( $action == 'createpage' || $action == 'createtalk' ) {
2847                                 $msg = 'nocreatetext';
2848                         } elseif ( $action == 'upload' ) {
2849                                 $msg = 'uploadnologintext';
2850                         } else { # Read
2851                                 $msg = 'loginreqpagetext';
2852                                 $displayReturnto = Title::newMainPage();
2853                         }
2854
2855                         $query = [];
2856
2857                         if ( $returnto ) {
2858                                 $query['returnto'] = $returnto->getPrefixedText();
2859
2860                                 if ( !$request->wasPosted() ) {
2861                                         $returntoquery = $request->getValues();
2862                                         unset( $returntoquery['title'] );
2863                                         unset( $returntoquery['returnto'] );
2864                                         unset( $returntoquery['returntoquery'] );
2865                                         $query['returntoquery'] = wfArrayToCgi( $returntoquery );
2866                                 }
2867                         }
2868                         $title = SpecialPage::getTitleFor( 'Userlogin' );
2869                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
2870                         $loginUrl = $title->getLinkURL( $query, false, PROTO_RELATIVE );
2871                         $loginLink = $linkRenderer->makeKnownLink(
2872                                 $title,
2873                                 $this->msg( 'loginreqlink' )->text(),
2874                                 [],
2875                                 $query
2876                         );
2877
2878                         $this->prepareErrorPage( $this->msg( 'loginreqtitle' ) );
2879                         $this->addHTML( $this->msg( $msg )->rawParams( $loginLink )->params( $loginUrl )->parse() );
2880
2881                         # Don't return to a page the user can't read otherwise
2882                         # we'll end up in a pointless loop
2883                         if ( $displayReturnto && $displayReturnto->userCan( 'read', $this->getUser() ) ) {
2884                                 $this->returnToMain( null, $displayReturnto );
2885                         }
2886                 } else {
2887                         $this->prepareErrorPage( $this->msg( 'permissionserrors' ) );
2888                         $this->addWikiTextAsInterface( $this->formatPermissionsErrorMessage( $errors, $action ) );
2889                 }
2890         }
2891
2892         /**
2893          * Display an error page indicating that a given version of MediaWiki is
2894          * required to use it
2895          *
2896          * @param mixed $version The version of MediaWiki needed to use the page
2897          */
2898         public function versionRequired( $version ) {
2899                 $this->prepareErrorPage( $this->msg( 'versionrequired', $version ) );
2900
2901                 $this->addWikiMsg( 'versionrequiredtext', $version );
2902                 $this->returnToMain();
2903         }
2904
2905         /**
2906          * Format a list of error messages
2907          *
2908          * @param array $errors Array of arrays returned by Title::getUserPermissionsErrors
2909          * @param string|null $action Action that was denied or null if unknown
2910          * @return string The wikitext error-messages, formatted into a list.
2911          */
2912         public function formatPermissionsErrorMessage( array $errors, $action = null ) {
2913                 if ( $action == null ) {
2914                         $text = $this->msg( 'permissionserrorstext', count( $errors ) )->plain() . "\n\n";
2915                 } else {
2916                         $action_desc = $this->msg( "action-$action" )->plain();
2917                         $text = $this->msg(
2918                                 'permissionserrorstext-withaction',
2919                                 count( $errors ),
2920                                 $action_desc
2921                         )->plain() . "\n\n";
2922                 }
2923
2924                 if ( count( $errors ) > 1 ) {
2925                         $text .= '<ul class="permissions-errors">' . "\n";
2926
2927                         foreach ( $errors as $error ) {
2928                                 $text .= '<li>';
2929                                 $text .= $this->msg( ...$error )->plain();
2930                                 $text .= "</li>\n";
2931                         }
2932                         $text .= '</ul>';
2933                 } else {
2934                         $text .= "<div class=\"permissions-errors\">\n" .
2935                                         $this->msg( ...reset( $errors ) )->plain() .
2936                                         "\n</div>";
2937                 }
2938
2939                 return $text;
2940         }
2941
2942         /**
2943          * Show a warning about replica DB lag
2944          *
2945          * If the lag is higher than $wgSlaveLagCritical seconds,
2946          * then the warning is a bit more obvious. If the lag is
2947          * lower than $wgSlaveLagWarning, then no warning is shown.
2948          *
2949          * @param int $lag Replica lag
2950          */
2951         public function showLagWarning( $lag ) {
2952                 $config = $this->getConfig();
2953                 if ( $lag >= $config->get( 'SlaveLagWarning' ) ) {
2954                         $lag = floor( $lag ); // floor to avoid nano seconds to display
2955                         $message = $lag < $config->get( 'SlaveLagCritical' )
2956                                 ? 'lag-warn-normal'
2957                                 : 'lag-warn-high';
2958                         $wrap = Html::rawElement( 'div', [ 'class' => "mw-{$message}" ], "\n$1\n" );
2959                         $this->wrapWikiMsg( "$wrap\n", [ $message, $this->getLanguage()->formatNum( $lag ) ] );
2960                 }
2961         }
2962
2963         /**
2964          * Output an error page
2965          *
2966          * @note FatalError exception class provides an alternative.
2967          * @param string $message Error to output. Must be escaped for HTML.
2968          */
2969         public function showFatalError( $message ) {
2970                 $this->prepareErrorPage( $this->msg( 'internalerror' ) );
2971
2972                 $this->addHTML( $message );
2973         }
2974
2975         /**
2976          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
2977          */
2978         public function showUnexpectedValueError( $name, $val ) {
2979                 wfDeprecated( __METHOD__, '1.32' );
2980                 $this->showFatalError( $this->msg( 'unexpected', $name, $val )->escaped() );
2981         }
2982
2983         /**
2984          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
2985          */
2986         public function showFileCopyError( $old, $new ) {
2987                 wfDeprecated( __METHOD__, '1.32' );
2988                 $this->showFatalError( $this->msg( 'filecopyerror', $old, $new )->escaped() );
2989         }
2990
2991         /**
2992          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
2993          */
2994         public function showFileRenameError( $old, $new ) {
2995                 wfDeprecated( __METHOD__, '1.32' );
2996                 $this->showFatalError( $this->msg( 'filerenameerror', $old, $new )->escpaed() );
2997         }
2998
2999         /**
3000          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
3001          */
3002         public function showFileDeleteError( $name ) {
3003                 wfDeprecated( __METHOD__, '1.32' );
3004                 $this->showFatalError( $this->msg( 'filedeleteerror', $name )->escaped() );
3005         }
3006
3007         /**
3008          * @deprecated 1.32 Use OutputPage::showFatalError or throw FatalError instead.
3009          */
3010         public function showFileNotFoundError( $name ) {
3011                 wfDeprecated( __METHOD__, '1.32' );
3012                 $this->showFatalError( $this->msg( 'filenotfound', $name )->escaped() );
3013         }
3014
3015         /**
3016          * Add a "return to" link pointing to a specified title
3017          *
3018          * @param Title $title Title to link
3019          * @param array $query Query string parameters
3020          * @param string|null $text Text of the link (input is not escaped)
3021          * @param array $options Options array to pass to Linker
3022          */
3023         public function addReturnTo( $title, array $query = [], $text = null, $options = [] ) {
3024                 $linkRenderer = MediaWikiServices::getInstance()
3025                         ->getLinkRendererFactory()->createFromLegacyOptions( $options );
3026                 $link = $this->msg( 'returnto' )->rawParams(
3027                         $linkRenderer->makeLink( $title, $text, [], $query ) )->escaped();
3028                 $this->addHTML( "<p id=\"mw-returnto\">{$link}</p>\n" );
3029         }
3030
3031         /**
3032          * Add a "return to" link pointing to a specified title,
3033          * or the title indicated in the request, or else the main page
3034          *
3035          * @param mixed|null $unused
3036          * @param Title|string|null $returnto Title or String to return to
3037          * @param string|null $returntoquery Query string for the return to link
3038          */
3039         public function returnToMain( $unused = null, $returnto = null, $returntoquery = null ) {
3040                 if ( $returnto == null ) {
3041                         $returnto = $this->getRequest()->getText( 'returnto' );
3042                 }
3043
3044                 if ( $returntoquery == null ) {
3045                         $returntoquery = $this->getRequest()->getText( 'returntoquery' );
3046                 }
3047
3048                 if ( $returnto === '' ) {
3049                         $returnto = Title::newMainPage();
3050                 }
3051
3052                 if ( is_object( $returnto ) ) {
3053                         $titleObj = $returnto;
3054                 } else {
3055                         $titleObj = Title::newFromText( $returnto );
3056                 }
3057                 // We don't want people to return to external interwiki. That
3058                 // might potentially be used as part of a phishing scheme
3059                 if ( !is_object( $titleObj ) || $titleObj->isExternal() ) {
3060                         $titleObj = Title::newMainPage();
3061                 }
3062
3063                 $this->addReturnTo( $titleObj, wfCgiToArray( $returntoquery ) );
3064         }
3065
3066         private function getRlClientContext() {
3067                 if ( !$this->rlClientContext ) {
3068                         $query = ResourceLoader::makeLoaderQuery(
3069                                 [], // modules; not relevant
3070                                 $this->getLanguage()->getCode(),
3071                                 $this->getSkin()->getSkinName(),
3072                                 $this->getUser()->isLoggedIn() ? $this->getUser()->getName() : null,
3073                                 null, // version; not relevant
3074                                 ResourceLoader::inDebugMode(),
3075                                 null, // only; not relevant
3076                                 $this->isPrintable(),
3077                                 $this->getRequest()->getBool( 'handheld' )
3078                         );
3079                         $this->rlClientContext = new ResourceLoaderContext(
3080                                 $this->getResourceLoader(),
3081                                 new FauxRequest( $query )
3082                         );
3083                         if ( $this->contentOverrideCallbacks ) {
3084                                 $this->rlClientContext = new DerivativeResourceLoaderContext( $this->rlClientContext );
3085                                 $this->rlClientContext->setContentOverrideCallback( function ( Title $title ) {
3086                                         foreach ( $this->contentOverrideCallbacks as $callback ) {
3087                                                 $content = $callback( $title );
3088                                                 if ( $content !== null ) {
3089                                                         $text = ContentHandler::getContentText( $content );
3090                                                         if ( strpos( $text, '</script>' ) !== false ) {
3091                                                                 // Proactively replace this so that we can display a message
3092                                                                 // to the user, instead of letting it go to Html::inlineScript(),
3093                                                                 // where it would be considered a server-side issue.
3094                                                                 $titleFormatted = $title->getPrefixedText();
3095                                                                 $content = new JavaScriptContent(
3096                                                                         Xml::encodeJsCall( 'mw.log.error', [
3097                                                                                 "Cannot preview $titleFormatted due to script-closing tag."
3098                                                                         ] )
3099                                                                 );
3100                                                         }
3101                                                         return $content;
3102                                                 }
3103                                         }
3104                                         return null;
3105                                 } );
3106                         }
3107                 }
3108                 return $this->rlClientContext;
3109         }
3110
3111         /**
3112          * Call this to freeze the module queue and JS config and create a formatter.
3113          *
3114          * Depending on the Skin, this may get lazy-initialised in either headElement() or
3115          * getBottomScripts(). See SkinTemplate::prepareQuickTemplate(). Calling this too early may
3116          * cause unexpected side-effects since disallowUserJs() may be called at any time to change
3117          * the module filters retroactively. Skins and extension hooks may also add modules until very
3118          * late in the request lifecycle.
3119          *
3120          * @return ResourceLoaderClientHtml
3121          */
3122         public function getRlClient() {
3123                 if ( !$this->rlClient ) {
3124                         $context = $this->getRlClientContext();
3125                         $rl = $this->getResourceLoader();
3126                         $this->addModules( [
3127                                 'user',
3128                                 'user.options',
3129                                 'user.tokens',
3130                         ] );
3131                         $this->addModuleStyles( [
3132                                 'site.styles',
3133                                 'noscript',
3134                                 'user.styles',
3135                         ] );
3136                         $this->getSkin()->setupSkinUserCss( $this );
3137
3138                         // Prepare exempt modules for buildExemptModules()
3139                         $exemptGroups = [ 'site' => [], 'noscript' => [], 'private' => [], 'user' => [] ];
3140                         $exemptStates = [];
3141                         $moduleStyles = $this->getModuleStyles( /*filter*/ true );
3142
3143                         // Preload getTitleInfo for isKnownEmpty calls below and in ResourceLoaderClientHtml
3144                         // Separate user-specific batch for improved cache-hit ratio.
3145                         $userBatch = [ 'user.styles', 'user' ];
3146                         $siteBatch = array_diff( $moduleStyles, $userBatch );
3147                         $dbr = wfGetDB( DB_REPLICA );
3148                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $siteBatch );
3149                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $userBatch );
3150
3151                         // Filter out modules handled by buildExemptModules()
3152                         $moduleStyles = array_filter( $moduleStyles,
3153                                 function ( $name ) use ( $rl, $context, &$exemptGroups, &$exemptStates ) {
3154                                         $module = $rl->getModule( $name );
3155                                         if ( $module ) {
3156                                                 $group = $module->getGroup();
3157                                                 if ( isset( $exemptGroups[$group] ) ) {
3158                                                         $exemptStates[$name] = 'ready';
3159                                                         if ( !$module->isKnownEmpty( $context ) ) {
3160                                                                 // E.g. Don't output empty <styles>
3161                                                                 $exemptGroups[$group][] = $name;
3162                                                         }
3163                                                         return false;
3164                                                 }
3165                                         }
3166                                         return true;
3167                                 }
3168                         );
3169                         $this->rlExemptStyleModules = $exemptGroups;
3170
3171                         $rlClient = new ResourceLoaderClientHtml( $context, [
3172                                 'target' => $this->getTarget(),
3173                                 'nonce' => $this->getCSPNonce(),
3174                                 // When 'safemode', disallowUserJs(), or reduceAllowedModules() is used
3175                                 // to only restrict modules to ORIGIN_CORE (ie. disallow ORIGIN_USER), the list of
3176                                 // modules enqueud for loading on this page is filtered to just those.
3177                                 // However, to make sure we also apply the restriction to dynamic dependencies and
3178                                 // lazy-loaded modules at run-time on the client-side, pass 'safemode' down to the
3179                                 // StartupModule so that the client-side registry will not contain any restricted
3180                                 // modules either. (T152169, T185303)
3181                                 'safemode' => ( $this->getAllowedModules( ResourceLoaderModule::TYPE_COMBINED )
3182                                         <= ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
3183                                 ) ? '1' : null,
3184                         ] );
3185                         $rlClient->setConfig( $this->getJSVars() );
3186                         $rlClient->setModules( $this->getModules( /*filter*/ true ) );
3187                         $rlClient->setModuleStyles( $moduleStyles );
3188                         $rlClient->setModuleScripts( $this->getModuleScripts( /*filter*/ true ) );
3189                         $rlClient->setExemptStates( $exemptStates );
3190                         $this->rlClient = $rlClient;
3191                 }
3192                 return $this->rlClient;
3193         }
3194
3195         /**
3196          * @param Skin $sk The given Skin
3197          * @param bool $includeStyle Unused
3198          * @return string The doctype, opening "<html>", and head element.
3199          */
3200         public function headElement( Skin $sk, $includeStyle = true ) {
3201                 $userdir = $this->getLanguage()->getDir();
3202                 $sitedir = MediaWikiServices::getInstance()->getContentLanguage()->getDir();
3203
3204                 $pieces = [];
3205                 $pieces[] = Html::htmlHeader( Sanitizer::mergeAttributes(
3206                         $this->getRlClient()->getDocumentAttributes(),
3207                         $sk->getHtmlElementAttributes()
3208                 ) );
3209                 $pieces[] = Html::openElement( 'head' );
3210
3211                 if ( $this->getHTMLTitle() == '' ) {
3212                         $this->setHTMLTitle( $this->msg( 'pagetitle', $this->getPageTitle() )->inContentLanguage() );
3213                 }
3214
3215                 if ( !Html::isXmlMimeType( $this->getConfig()->get( 'MimeType' ) ) ) {
3216                         // Add <meta charset="UTF-8">
3217                         // This should be before <title> since it defines the charset used by
3218                         // text including the text inside <title>.
3219                         // The spec recommends defining XHTML5's charset using the XML declaration
3220                         // instead of meta.
3221                         // Our XML declaration is output by Html::htmlHeader.
3222                         // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-content-type
3223                         // https://html.spec.whatwg.org/multipage/semantics.html#charset
3224                         $pieces[] = Html::element( 'meta', [ 'charset' => 'UTF-8' ] );
3225                 }
3226
3227                 $pieces[] = Html::element( 'title', null, $this->getHTMLTitle() );
3228                 $pieces[] = $this->getRlClient()->getHeadHtml();
3229                 $pieces[] = $this->buildExemptModules();
3230                 $pieces = array_merge( $pieces, array_values( $this->getHeadLinksArray() ) );
3231                 $pieces = array_merge( $pieces, array_values( $this->mHeadItems ) );
3232
3233                 // Use an IE conditional comment to serve the script only to old IE
3234                 $pieces[] = '<!--[if lt IE 9]>' .
3235                         ResourceLoaderClientHtml::makeLoad(
3236                                 ResourceLoaderContext::newDummyContext(),
3237                                 [ 'html5shiv' ],
3238                                 ResourceLoaderModule::TYPE_SCRIPTS,
3239                                 [ 'sync' => true ],
3240                                 $this->getCSPNonce()
3241                         ) .
3242                         '<![endif]-->';
3243
3244                 $pieces[] = Html::closeElement( 'head' );
3245
3246                 $bodyClasses = $this->mAdditionalBodyClasses;
3247                 $bodyClasses[] = 'mediawiki';
3248
3249                 # Classes for LTR/RTL directionality support
3250                 $bodyClasses[] = $userdir;
3251                 $bodyClasses[] = "sitedir-$sitedir";
3252
3253                 $underline = $this->getUser()->getOption( 'underline' );
3254                 if ( $underline < 2 ) {
3255                         // The following classes can be used here:
3256                         // * mw-underline-always
3257                         // * mw-underline-never
3258                         $bodyClasses[] = 'mw-underline-' . ( $underline ? 'always' : 'never' );
3259                 }
3260
3261                 if ( $this->getLanguage()->capitalizeAllNouns() ) {
3262                         # A <body> class is probably not the best way to do this . . .
3263                         $bodyClasses[] = 'capitalize-all-nouns';
3264                 }
3265
3266                 // Parser feature migration class
3267                 // The idea is that this will eventually be removed, after the wikitext
3268                 // which requires it is cleaned up.
3269                 $bodyClasses[] = 'mw-hide-empty-elt';
3270
3271                 $bodyClasses[] = $sk->getPageClasses( $this->getTitle() );
3272                 $bodyClasses[] = 'skin-' . Sanitizer::escapeClass( $sk->getSkinName() );
3273                 $bodyClasses[] =
3274                         'action-' . Sanitizer::escapeClass( Action::getActionName( $this->getContext() ) );
3275
3276                 $bodyAttrs = [];
3277                 // While the implode() is not strictly needed, it's used for backwards compatibility
3278                 // (this used to be built as a string and hooks likely still expect that).
3279                 $bodyAttrs['class'] = implode( ' ', $bodyClasses );
3280
3281                 // Allow skins and extensions to add body attributes they need
3282                 $sk->addToBodyAttributes( $this, $bodyAttrs );
3283                 Hooks::run( 'OutputPageBodyAttributes', [ $this, $sk, &$bodyAttrs ] );
3284
3285                 $pieces[] = Html::openElement( 'body', $bodyAttrs );
3286
3287                 return self::combineWrappedStrings( $pieces );
3288         }
3289
3290         /**
3291          * Get a ResourceLoader object associated with this OutputPage
3292          *
3293          * @return ResourceLoader
3294          */
3295         public function getResourceLoader() {
3296                 if ( is_null( $this->mResourceLoader ) ) {
3297                         // Lazy-initialise as needed
3298                         $this->mResourceLoader = MediaWikiServices::getInstance()->getResourceLoader();
3299                 }
3300                 return $this->mResourceLoader;
3301         }
3302
3303         /**
3304          * Explicily load or embed modules on a page.
3305          *
3306          * @param array|string $modules One or more module names
3307          * @param string $only ResourceLoaderModule TYPE_ class constant
3308          * @param array $extraQuery [optional] Array with extra query parameters for the request
3309          * @return string|WrappedStringList HTML
3310          */
3311         public function makeResourceLoaderLink( $modules, $only, array $extraQuery = [] ) {
3312                 // Apply 'target' and 'origin' filters
3313                 $modules = $this->filterModules( (array)$modules, null, $only );
3314
3315                 return ResourceLoaderClientHtml::makeLoad(
3316                         $this->getRlClientContext(),
3317                         $modules,
3318                         $only,
3319                         $extraQuery,
3320                         $this->getCSPNonce()
3321                 );
3322         }
3323
3324         /**
3325          * Combine WrappedString chunks and filter out empty ones
3326          *
3327          * @param array $chunks
3328          * @return string|WrappedStringList HTML
3329          */
3330         protected static function combineWrappedStrings( array $chunks ) {
3331                 // Filter out empty values
3332                 $chunks = array_filter( $chunks, 'strlen' );
3333                 return WrappedString::join( "\n", $chunks );
3334         }
3335
3336         /**
3337          * JS stuff to put at the bottom of the `<body>`.
3338          * These are legacy scripts ($this->mScripts), and user JS.
3339          *
3340          * @return string|WrappedStringList HTML
3341          */
3342         public function getBottomScripts() {
3343                 $chunks = [];
3344                 $chunks[] = $this->getRlClient()->getBodyHtml();
3345
3346                 // Legacy non-ResourceLoader scripts
3347                 $chunks[] = $this->mScripts;
3348
3349                 if ( $this->limitReportJSData ) {
3350                         $chunks[] = ResourceLoader::makeInlineScript(
3351                                 ResourceLoader::makeConfigSetScript(
3352                                         [ 'wgPageParseReport' => $this->limitReportJSData ]
3353                                 ),
3354                                 $this->getCSPNonce()
3355                         );
3356                 }
3357
3358                 return self::combineWrappedStrings( $chunks );
3359         }
3360
3361         /**
3362          * Get the javascript config vars to include on this page
3363          *
3364          * @return array Array of javascript config vars
3365          * @since 1.23
3366          */
3367         public function getJsConfigVars() {
3368                 return $this->mJsConfigVars;
3369         }
3370
3371         /**
3372          * Add one or more variables to be set in mw.config in JavaScript
3373          *
3374          * @param string|array $keys Key or array of key/value pairs
3375          * @param mixed|null $value [optional] Value of the configuration variable
3376          */
3377         public function addJsConfigVars( $keys, $value = null ) {
3378                 if ( is_array( $keys ) ) {
3379                         foreach ( $keys as $key => $value ) {
3380                                 $this->mJsConfigVars[$key] = $value;
3381                         }
3382                         return;
3383                 }
3384
3385                 $this->mJsConfigVars[$keys] = $value;
3386         }
3387
3388         /**
3389          * Get an array containing the variables to be set in mw.config in JavaScript.
3390          *
3391          * Do not add things here which can be evaluated in ResourceLoaderStartUpModule
3392          * - in other words, page-independent/site-wide variables (without state).
3393          * You will only be adding bloat to the html page and causing page caches to
3394          * have to be purged on configuration changes.
3395          * @return array
3396          */
3397         public function getJSVars() {
3398                 $curRevisionId = 0;
3399                 $articleId = 0;
3400                 $canonicalSpecialPageName = false; # T23115
3401                 $services = MediaWikiServices::getInstance();
3402
3403                 $title = $this->getTitle();
3404                 $ns = $title->getNamespace();
3405                 $canonicalNamespace = MWNamespace::exists( $ns )
3406                         ? MWNamespace::getCanonicalName( $ns )
3407                         : $title->getNsText();
3408
3409                 $sk = $this->getSkin();
3410                 // Get the relevant title so that AJAX features can use the correct page name
3411                 // when making API requests from certain special pages (T36972).
3412                 $relevantTitle = $sk->getRelevantTitle();
3413                 $relevantUser = $sk->getRelevantUser();
3414
3415                 if ( $ns == NS_SPECIAL ) {
3416                         list( $canonicalSpecialPageName, /*...*/ ) =
3417                                 $services->getSpecialPageFactory()->
3418                                         resolveAlias( $title->getDBkey() );
3419                 } elseif ( $this->canUseWikiPage() ) {
3420                         $wikiPage = $this->getWikiPage();
3421                         $curRevisionId = $wikiPage->getLatest();
3422                         $articleId = $wikiPage->getId();
3423                 }
3424
3425                 $lang = $title->getPageViewLanguage();
3426
3427                 // Pre-process information
3428                 $separatorTransTable = $lang->separatorTransformTable();
3429                 $separatorTransTable = $separatorTransTable ?: [];
3430                 $compactSeparatorTransTable = [
3431                         implode( "\t", array_keys( $separatorTransTable ) ),
3432                         implode( "\t", $separatorTransTable ),
3433                 ];
3434                 $digitTransTable = $lang->digitTransformTable();
3435                 $digitTransTable = $digitTransTable ?: [];
3436                 $compactDigitTransTable = [
3437                         implode( "\t", array_keys( $digitTransTable ) ),
3438                         implode( "\t", $digitTransTable ),
3439                 ];
3440
3441                 $user = $this->getUser();
3442
3443                 $vars = [
3444                         'wgCanonicalNamespace' => $canonicalNamespace,
3445                         'wgCanonicalSpecialPageName' => $canonicalSpecialPageName,
3446                         'wgNamespaceNumber' => $title->getNamespace(),
3447                         'wgPageName' => $title->getPrefixedDBkey(),
3448                         'wgTitle' => $title->getText(),
3449                         'wgCurRevisionId' => $curRevisionId,
3450                         'wgRevisionId' => (int)$this->getRevisionId(),
3451                         'wgArticleId' => $articleId,
3452                         'wgIsArticle' => $this->isArticle(),
3453                         'wgIsRedirect' => $title->isRedirect(),
3454                         'wgAction' => Action::getActionName( $this->getContext() ),
3455                         'wgUserName' => $user->isAnon() ? null : $user->getName(),
3456                         'wgUserGroups' => $user->getEffectiveGroups(),
3457                         'wgCategories' => $this->getCategories(),
3458                         'wgBreakFrames' => $this->getFrameOptions() == 'DENY',
3459                         'wgPageContentLanguage' => $lang->getCode(),
3460                         'wgPageContentModel' => $title->getContentModel(),
3461                         'wgSeparatorTransformTable' => $compactSeparatorTransTable,
3462                         'wgDigitTransformTable' => $compactDigitTransTable,
3463                         'wgDefaultDateFormat' => $lang->getDefaultDateFormat(),
3464                         'wgMonthNames' => $lang->getMonthNamesArray(),
3465                         'wgMonthNamesShort' => $lang->getMonthAbbreviationsArray(),
3466                         'wgRelevantPageName' => $relevantTitle->getPrefixedDBkey(),
3467                         'wgRelevantArticleId' => $relevantTitle->getArticleID(),
3468                         'wgRequestId' => WebRequest::getRequestId(),
3469                         'wgCSPNonce' => $this->getCSPNonce(),
3470                 ];
3471
3472                 if ( $user->isLoggedIn() ) {
3473                         $vars['wgUserId'] = $user->getId();
3474                         $vars['wgUserEditCount'] = $user->getEditCount();
3475                         $userReg = $user->getRegistration();
3476                         $vars['wgUserRegistration'] = $userReg ? wfTimestamp( TS_UNIX, $userReg ) * 1000 : null;
3477                         // Get the revision ID of the oldest new message on the user's talk
3478                         // page. This can be used for constructing new message alerts on
3479                         // the client side.
3480                         $vars['wgUserNewMsgRevisionId'] = $user->getNewMessageRevisionId();
3481                 }
3482
3483                 $contLang = $services->getContentLanguage();
3484                 if ( $contLang->hasVariants() ) {
3485                         $vars['wgUserVariant'] = $contLang->getPreferredVariant();
3486                 }
3487                 // Same test as SkinTemplate
3488                 $vars['wgIsProbablyEditable'] = $title->quickUserCan( 'edit', $user )
3489                         && ( $title->exists() || $title->quickUserCan( 'create', $user ) );
3490
3491                 $vars['wgRelevantPageIsProbablyEditable'] = $relevantTitle
3492                         && $relevantTitle->quickUserCan( 'edit', $user )
3493                         && ( $relevantTitle->exists() || $relevantTitle->quickUserCan( 'create', $user ) );
3494
3495                 foreach ( $title->getRestrictionTypes() as $type ) {
3496                         // Following keys are set in $vars:
3497                         // wgRestrictionCreate, wgRestrictionEdit, wgRestrictionMove, wgRestrictionUpload
3498                         $vars['wgRestriction' . ucfirst( $type )] = $title->getRestrictions( $type );
3499                 }
3500
3501                 if ( $title->isMainPage() ) {
3502                         $vars['wgIsMainPage'] = true;
3503                 }
3504
3505                 if ( $this->mRedirectedFrom ) {
3506                         $vars['wgRedirectedFrom'] = $this->mRedirectedFrom->getPrefixedDBkey();
3507                 }
3508
3509                 if ( $relevantUser ) {
3510                         $vars['wgRelevantUserName'] = $relevantUser->getName();
3511                 }
3512
3513                 // Allow extensions to add their custom variables to the mw.config map.
3514                 // Use the 'ResourceLoaderGetConfigVars' hook if the variable is not
3515                 // page-dependant but site-wide (without state).
3516                 // Alternatively, you may want to use OutputPage->addJsConfigVars() instead.
3517                 Hooks::run( 'MakeGlobalVariablesScript', [ &$vars, $this ] );
3518
3519                 // Merge in variables from addJsConfigVars last
3520                 return array_merge( $vars, $this->getJsConfigVars() );
3521         }
3522
3523         /**
3524          * To make it harder for someone to slip a user a fake
3525          * JavaScript or CSS preview, a random token
3526          * is associated with the login session. If it's not
3527          * passed back with the preview request, we won't render
3528          * the code.
3529          *
3530          * @return bool
3531          */
3532         public function userCanPreview() {
3533                 $request = $this->getRequest();
3534                 if (
3535                         $request->getVal( 'action' ) !== 'submit' ||
3536                         !$request->wasPosted()
3537                 ) {
3538                         return false;
3539                 }
3540
3541                 $user = $this->getUser();
3542
3543                 if ( !$user->isLoggedIn() ) {
3544                         // Anons have predictable edit tokens
3545                         return false;
3546                 }
3547                 if ( !$user->matchEditToken( $request->getVal( 'wpEditToken' ) ) ) {
3548                         return false;
3549                 }
3550
3551                 $title = $this->getTitle();
3552                 $errors = $title->getUserPermissionsErrors( 'edit', $user );
3553                 if ( count( $errors ) !== 0 ) {
3554                         return false;
3555                 }
3556
3557                 return true;
3558         }
3559
3560         /**
3561          * @return array Array in format "link name or number => 'link html'".
3562          */
3563         public function getHeadLinksArray() {
3564                 global $wgVersion;
3565
3566                 $tags = [];
3567                 $config = $this->getConfig();
3568
3569                 $canonicalUrl = $this->mCanonicalUrl;
3570
3571                 $tags['meta-generator'] = Html::element( 'meta', [
3572                         'name' => 'generator',
3573                         'content' => "MediaWiki $wgVersion",
3574                 ] );
3575
3576                 if ( $config->get( 'ReferrerPolicy' ) !== false ) {
3577                         // Per https://w3c.github.io/webappsec-referrer-policy/#unknown-policy-values
3578                         // fallbacks should come before the primary value so we need to reverse the array.
3579                         foreach ( array_reverse( (array)$config->get( 'ReferrerPolicy' ) ) as $i => $policy ) {
3580                                 $tags["meta-referrer-$i"] = Html::element( 'meta', [
3581                                         'name' => 'referrer',
3582                                         'content' => $policy,
3583                                 ] );
3584                         }
3585                 }
3586
3587                 $p = "{$this->mIndexPolicy},{$this->mFollowPolicy}";
3588                 if ( $p !== 'index,follow' ) {
3589                         // http://www.robotstxt.org/wc/meta-user.html
3590                         // Only show if it's different from the default robots policy
3591                         $tags['meta-robots'] = Html::element( 'meta', [
3592                                 'name' => 'robots',
3593                                 'content' => $p,
3594                         ] );
3595                 }
3596
3597                 foreach ( $this->mMetatags as $tag ) {
3598                         if ( strncasecmp( $tag[0], 'http:', 5 ) === 0 ) {
3599                                 $a = 'http-equiv';
3600                                 $tag[0] = substr( $tag[0], 5 );
3601                         } elseif ( strncasecmp( $tag[0], 'og:', 3 ) === 0 ) {
3602                                 $a = 'property';
3603                         } else {
3604                                 $a = 'name';
3605                         }
3606                         $tagName = "meta-{$tag[0]}";
3607                         if ( isset( $tags[$tagName] ) ) {
3608                                 $tagName .= $tag[1];
3609                         }
3610                         $tags[$tagName] = Html::element( 'meta',
3611                                 [
3612                                         $a => $tag[0],
3613                                         'content' => $tag[1]
3614                                 ]
3615                         );
3616                 }
3617
3618                 foreach ( $this->mLinktags as $tag ) {
3619                         $tags[] = Html::element( 'link', $tag );
3620                 }
3621
3622                 # Universal edit button
3623                 if ( $config->get( 'UniversalEditButton' ) && $this->isArticleRelated() ) {
3624                         $user = $this->getUser();
3625                         if ( $this->getTitle()->quickUserCan( 'edit', $user )
3626                                 && ( $this->getTitle()->exists() ||
3627                                         $this->getTitle()->quickUserCan( 'create', $user ) )
3628                         ) {
3629                                 // Original UniversalEditButton
3630                                 $msg = $this->msg( 'edit' )->text();
3631                                 $tags['universal-edit-button'] = Html::element( 'link', [
3632                                         'rel' => 'alternate',
3633                                         'type' => 'application/x-wiki',
3634                                         'title' => $msg,
3635                                         'href' => $this->getTitle()->getEditURL(),
3636                                 ] );
3637                                 // Alternate edit link
3638                                 $tags['alternative-edit'] = Html::element( 'link', [
3639                                         'rel' => 'edit',
3640                                         'title' => $msg,
3641                                         'href' => $this->getTitle()->getEditURL(),
3642                                 ] );
3643                         }
3644                 }
3645
3646                 # Generally the order of the favicon and apple-touch-icon links
3647                 # should not matter, but Konqueror (3.5.9 at least) incorrectly
3648                 # uses whichever one appears later in the HTML source. Make sure
3649                 # apple-touch-icon is specified first to avoid this.
3650                 if ( $config->get( 'AppleTouchIcon' ) !== false ) {
3651                         $tags['apple-touch-icon'] = Html::element( 'link', [
3652                                 'rel' => 'apple-touch-icon',
3653                                 'href' => $config->get( 'AppleTouchIcon' )
3654                         ] );
3655                 }
3656
3657                 if ( $config->get( 'Favicon' ) !== false ) {
3658                         $tags['favicon'] = Html::element( 'link', [
3659                                 'rel' => 'shortcut icon',
3660                                 'href' => $config->get( 'Favicon' )
3661                         ] );
3662                 }
3663
3664                 # OpenSearch description link
3665                 $tags['opensearch'] = Html::element( 'link', [
3666                         'rel' => 'search',
3667                         'type' => 'application/opensearchdescription+xml',
3668                         'href' => wfScript( 'opensearch_desc' ),
3669                         'title' => $this->msg( 'opensearch-desc' )->inContentLanguage()->text(),
3670                 ] );
3671
3672                 # Real Simple Discovery link, provides auto-discovery information
3673                 # for the MediaWiki API (and potentially additional custom API
3674                 # support such as WordPress or Twitter-compatible APIs for a
3675                 # blogging extension, etc)
3676                 $tags['rsd'] = Html::element( 'link', [
3677                         'rel' => 'EditURI',
3678                         'type' => 'application/rsd+xml',
3679                         // Output a protocol-relative URL here if $wgServer is protocol-relative.
3680                         // Whether RSD accepts relative or protocol-relative URLs is completely
3681                         // undocumented, though.
3682                         'href' => wfExpandUrl( wfAppendQuery(
3683                                 wfScript( 'api' ),
3684                                 [ 'action' => 'rsd' ] ),
3685                                 PROTO_RELATIVE
3686                         ),
3687                 ] );
3688
3689                 # Language variants
3690                 if ( !$config->get( 'DisableLangConversion' ) ) {
3691                         $lang = $this->getTitle()->getPageLanguage();
3692                         if ( $lang->hasVariants() ) {
3693                                 $variants = $lang->getVariants();
3694                                 foreach ( $variants as $variant ) {
3695                                         $tags["variant-$variant"] = Html::element( 'link', [
3696                                                 'rel' => 'alternate',
3697                                                 'hreflang' => LanguageCode::bcp47( $variant ),
3698                                                 'href' => $this->getTitle()->getLocalURL(
3699                                                         [ 'variant' => $variant ] )
3700                                                 ]
3701                                         );
3702                                 }
3703                                 # x-default link per https://support.google.com/webmasters/answer/189077?hl=en
3704                                 $tags["variant-x-default"] = Html::element( 'link', [
3705                                         'rel' => 'alternate',
3706                                         'hreflang' => 'x-default',
3707                                         'href' => $this->getTitle()->getLocalURL() ] );
3708                         }
3709                 }
3710
3711                 # Copyright
3712                 if ( $this->copyrightUrl !== null ) {
3713                         $copyright = $this->copyrightUrl;
3714                 } else {
3715                         $copyright = '';
3716                         if ( $config->get( 'RightsPage' ) ) {
3717                                 $copy = Title::newFromText( $config->get( 'RightsPage' ) );
3718
3719                                 if ( $copy ) {
3720                                         $copyright = $copy->getLocalURL();
3721                                 }
3722                         }
3723
3724                         if ( !$copyright && $config->get( 'RightsUrl' ) ) {
3725                                 $copyright = $config->get( 'RightsUrl' );
3726                         }
3727                 }
3728
3729                 if ( $copyright ) {
3730                         $tags['copyright'] = Html::element( 'link', [
3731                                 'rel' => 'license',
3732                                 'href' => $copyright ]
3733                         );
3734                 }
3735
3736                 # Feeds
3737                 if ( $config->get( 'Feed' ) ) {
3738                         $feedLinks = [];
3739
3740                         foreach ( $this->getSyndicationLinks() as $format => $link ) {
3741                                 # Use the page name for the title.  In principle, this could
3742                                 # lead to issues with having the same name for different feeds
3743                                 # corresponding to the same page, but we can't avoid that at
3744                                 # this low a level.
3745
3746                                 $feedLinks[] = $this->feedLink(
3747                                         $format,
3748                                         $link,
3749                                         # Used messages: 'page-rss-feed' and 'page-atom-feed' (for an easier grep)
3750                                         $this->msg(
3751                                                 "page-{$format}-feed", $this->getTitle()->getPrefixedText()
3752                                         )->text()
3753                                 );
3754                         }
3755
3756                         # Recent changes feed should appear on every page (except recentchanges,
3757                         # that would be redundant). Put it after the per-page feed to avoid
3758                         # changing existing behavior. It's still available, probably via a
3759                         # menu in your browser. Some sites might have a different feed they'd
3760                         # like to promote instead of the RC feed (maybe like a "Recent New Articles"
3761                         # or "Breaking news" one). For this, we see if $wgOverrideSiteFeed is defined.
3762                         # If so, use it instead.
3763                         $sitename = $config->get( 'Sitename' );
3764                         if ( $config->get( 'OverrideSiteFeed' ) ) {
3765                                 foreach ( $config->get( 'OverrideSiteFeed' ) as $type => $feedUrl ) {
3766                                         // Note, this->feedLink escapes the url.
3767                                         $feedLinks[] = $this->feedLink(
3768                                                 $type,
3769                                                 $feedUrl,
3770                                                 $this->msg( "site-{$type}-feed", $sitename )->text()
3771                                         );
3772                                 }
3773                         } elseif ( !$this->getTitle()->isSpecial( 'Recentchanges' ) ) {
3774                                 $rctitle = SpecialPage::getTitleFor( 'Recentchanges' );
3775                                 foreach ( $config->get( 'AdvertisedFeedTypes' ) as $format ) {
3776                                         $feedLinks[] = $this->feedLink(
3777                                                 $format,
3778                                                 $rctitle->getLocalURL( [ 'feed' => $format ] ),
3779                                                 # For grep: 'site-rss-feed', 'site-atom-feed'
3780                                                 $this->msg( "site-{$format}-feed", $sitename )->text()
3781                                         );
3782                                 }
3783                         }
3784
3785                         # Allow extensions to change the list pf feeds. This hook is primarily for changing,
3786                         # manipulating or removing existing feed tags. If you want to add new feeds, you should
3787                         # use OutputPage::addFeedLink() instead.
3788                         Hooks::run( 'AfterBuildFeedLinks', [ &$feedLinks ] );
3789
3790                         $tags += $feedLinks;
3791                 }
3792
3793                 # Canonical URL
3794                 if ( $config->get( 'EnableCanonicalServerLink' ) ) {
3795                         if ( $canonicalUrl !== false ) {
3796                                 $canonicalUrl = wfExpandUrl( $canonicalUrl, PROTO_CANONICAL );
3797                         } else {
3798                                 if ( $this->isArticleRelated() ) {
3799                                         // This affects all requests where "setArticleRelated" is true. This is
3800                                         // typically all requests that show content (query title, curid, oldid, diff),
3801                                         // and all wikipage actions (edit, delete, purge, info, history etc.).
3802                                         // It does not apply to File pages and Special pages.
3803                                         // 'history' and 'info' actions address page metadata rather than the page
3804                                         // content itself, so they may not be canonicalized to the view page url.
3805                                         // TODO: this ought to be better encapsulated in the Action class.
3806                                         $action = Action::getActionName( $this->getContext() );
3807                                         if ( in_array( $action, [ 'history', 'info' ] ) ) {
3808                                                 $query = "action={$action}";
3809                                         } else {
3810                                                 $query = '';
3811                                         }
3812                                         $canonicalUrl = $this->getTitle()->getCanonicalURL( $query );
3813                                 } else {
3814                                         $reqUrl = $this->getRequest()->getRequestURL();
3815                                         $canonicalUrl = wfExpandUrl( $reqUrl, PROTO_CANONICAL );
3816                                 }
3817                         }
3818                 }
3819                 if ( $canonicalUrl !== false ) {
3820                         $tags[] = Html::element( 'link', [
3821                                 'rel' => 'canonical',
3822                                 'href' => $canonicalUrl
3823                         ] );
3824                 }
3825
3826                 // Allow extensions to add, remove and/or otherwise manipulate these links
3827                 // If you want only to *add* <head> links, please use the addHeadItem()
3828                 // (or addHeadItems() for multiple items) method instead.
3829                 // This hook is provided as a last resort for extensions to modify these
3830                 // links before the output is sent to client.
3831                 Hooks::run( 'OutputPageAfterGetHeadLinksArray', [ &$tags, $this ] );
3832
3833                 return $tags;
3834         }
3835
3836         /**
3837          * Generate a "<link rel/>" for a feed.
3838          *
3839          * @param string $type Feed type
3840          * @param string $url URL to the feed
3841          * @param string $text Value of the "title" attribute
3842          * @return string HTML fragment
3843          */
3844         private function feedLink( $type, $url, $text ) {
3845                 return Html::element( 'link', [
3846                         'rel' => 'alternate',
3847                         'type' => "application/$type+xml",
3848                         'title' => $text,
3849                         'href' => $url ]
3850                 );
3851         }
3852
3853         /**
3854          * Add a local or specified stylesheet, with the given media options.
3855          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3856          *
3857          * @param string $style URL to the file
3858          * @param string $media To specify a media type, 'screen', 'printable', 'handheld' or any.
3859          * @param string $condition For IE conditional comments, specifying an IE version
3860          * @param string $dir Set to 'rtl' or 'ltr' for direction-specific sheets
3861          */
3862         public function addStyle( $style, $media = '', $condition = '', $dir = '' ) {
3863                 $options = [];
3864                 if ( $media ) {
3865                         $options['media'] = $media;
3866                 }
3867                 if ( $condition ) {
3868                         $options['condition'] = $condition;
3869                 }
3870                 if ( $dir ) {
3871                         $options['dir'] = $dir;
3872                 }
3873                 $this->styles[$style] = $options;
3874         }
3875
3876         /**
3877          * Adds inline CSS styles
3878          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3879          *
3880          * @param mixed $style_css Inline CSS
3881          * @param string $flip Set to 'flip' to flip the CSS if needed
3882          */
3883         public function addInlineStyle( $style_css, $flip = 'noflip' ) {
3884                 if ( $flip === 'flip' && $this->getLanguage()->isRTL() ) {
3885                         # If wanted, and the interface is right-to-left, flip the CSS
3886                         $style_css = CSSJanus::transform( $style_css, true, false );
3887                 }
3888                 $this->mInlineStyles .= Html::inlineStyle( $style_css );
3889         }
3890
3891         /**
3892          * Build exempt modules and legacy non-ResourceLoader styles.
3893          *
3894          * @return string|WrappedStringList HTML
3895          */
3896         protected function buildExemptModules() {
3897                 $chunks = [];
3898                 // Things that go after the ResourceLoaderDynamicStyles marker
3899                 $append = [];
3900
3901                 // We want site, private and user styles to override dynamically added styles from
3902                 // general modules, but we want dynamically added styles to override statically added
3903                 // style modules. So the order has to be:
3904                 // - page style modules (formatted by ResourceLoaderClientHtml::getHeadHtml())
3905                 // - dynamically loaded styles (added by mw.loader before ResourceLoaderDynamicStyles)
3906                 // - ResourceLoaderDynamicStyles marker
3907                 // - site/private/user styles
3908
3909                 // Add legacy styles added through addStyle()/addInlineStyle() here
3910                 $chunks[] = implode( '', $this->buildCssLinksArray() ) . $this->mInlineStyles;
3911
3912                 $chunks[] = Html::element(
3913                         'meta',
3914                         [ 'name' => 'ResourceLoaderDynamicStyles', 'content' => '' ]
3915                 );
3916
3917                 $separateReq = [ 'site.styles', 'user.styles' ];
3918                 foreach ( $this->rlExemptStyleModules as $group => $moduleNames ) {
3919                         // Combinable modules
3920                         $chunks[] = $this->makeResourceLoaderLink(
3921                                 array_diff( $moduleNames, $separateReq ),
3922                                 ResourceLoaderModule::TYPE_STYLES
3923                         );
3924
3925                         foreach ( array_intersect( $moduleNames, $separateReq ) as $name ) {
3926                                 // These require their own dedicated request in order to support "@import"
3927                                 // syntax, which is incompatible with concatenation. (T147667, T37562)
3928                                 $chunks[] = $this->makeResourceLoaderLink( $name,
3929                                         ResourceLoaderModule::TYPE_STYLES
3930                                 );
3931                         }
3932                 }
3933
3934                 return self::combineWrappedStrings( array_merge( $chunks, $append ) );
3935         }
3936
3937         /**
3938          * @return array
3939          */
3940         public function buildCssLinksArray() {
3941                 $links = [];
3942
3943                 foreach ( $this->styles as $file => $options ) {
3944                         $link = $this->styleLink( $file, $options );
3945                         if ( $link ) {
3946                                 $links[$file] = $link;
3947                         }
3948                 }
3949                 return $links;
3950         }
3951
3952         /**
3953          * Generate \<link\> tags for stylesheets
3954          *
3955          * @param string $style URL to the file
3956          * @param array $options Option, can contain 'condition', 'dir', 'media' keys
3957          * @return string HTML fragment
3958          */
3959         protected function styleLink( $style, array $options ) {
3960                 if ( isset( $options['dir'] ) ) {
3961                         if ( $this->getLanguage()->getDir() != $options['dir'] ) {
3962                                 return '';
3963                         }
3964                 }
3965
3966                 if ( isset( $options['media'] ) ) {
3967                         $media = self::transformCssMedia( $options['media'] );
3968                         if ( is_null( $media ) ) {
3969                                 return '';
3970                         }
3971                 } else {
3972                         $media = 'all';
3973                 }
3974
3975                 if ( substr( $style, 0, 1 ) == '/' ||
3976                         substr( $style, 0, 5 ) == 'http:' ||
3977                         substr( $style, 0, 6 ) == 'https:' ) {
3978                         $url = $style;
3979                 } else {
3980                         $config = $this->getConfig();
3981                         // Append file hash as query parameter
3982                         $url = self::transformResourcePath(
3983                                 $config,
3984                                 $config->get( 'StylePath' ) . '/' . $style
3985                         );
3986                 }
3987
3988                 $link = Html::linkedStyle( $url, $media );
3989
3990                 if ( isset( $options['condition'] ) ) {
3991                         $condition = htmlspecialchars( $options['condition'] );
3992                         $link = "<!--[if $condition]>$link<![endif]-->";
3993                 }
3994                 return $link;
3995         }
3996
3997         /**
3998          * Transform path to web-accessible static resource.
3999          *
4000          * This is used to add a validation hash as query string.
4001          * This aids various behaviors:
4002          *
4003          * - Put long Cache-Control max-age headers on responses for improved
4004          *   cache performance.
4005          * - Get the correct version of a file as expected by the current page.
4006          * - Instantly get the updated version of a file after deployment.
4007          *
4008          * Avoid using this for urls included in HTML as otherwise clients may get different
4009          * versions of a resource when navigating the site depending on when the page was cached.
4010          * If changes to the url propagate, this is not a problem (e.g. if the url is in
4011          * an external stylesheet).
4012          *
4013          * @since 1.27
4014          * @param Config $config
4015          * @param string $path Path-absolute URL to file (from document root, must start with "/")
4016          * @return string URL
4017          */
4018         public static function transformResourcePath( Config $config, $path ) {
4019                 global $IP;
4020
4021                 $localDir = $IP;
4022                 $remotePathPrefix = $config->get( 'ResourceBasePath' );
4023                 if ( $remotePathPrefix === '' ) {
4024                         // The configured base path is required to be empty string for
4025                         // wikis in the domain root
4026                         $remotePath = '/';
4027                 } else {
4028                         $remotePath = $remotePathPrefix;
4029                 }
4030                 if ( strpos( $path, $remotePath ) !== 0 || substr( $path, 0, 2 ) === '//' ) {
4031                         // - Path is outside wgResourceBasePath, ignore.
4032                         // - Path is protocol-relative. Fixes T155310. Not supported by RelPath lib.
4033                         return $path;
4034                 }
4035                 // For files in resources, extensions/ or skins/, ResourceBasePath is preferred here.
4036                 // For other misc files in $IP, we'll fallback to that as well. There is, however, a fourth
4037                 // supported dir/path pair in the configuration (wgUploadDirectory, wgUploadPath)
4038                 // which is not expected to be in wgResourceBasePath on CDNs. (T155146)
4039                 $uploadPath = $config->get( 'UploadPath' );
4040                 if ( strpos( $path, $uploadPath ) === 0 ) {
4041                         $localDir = $config->get( 'UploadDirectory' );
4042                         $remotePathPrefix = $remotePath = $uploadPath;
4043                 }
4044
4045                 $path = RelPath::getRelativePath( $path, $remotePath );
4046                 return self::transformFilePath( $remotePathPrefix, $localDir, $path );
4047         }
4048
4049         /**
4050          * Utility method for transformResourceFilePath().
4051          *
4052          * Caller is responsible for ensuring the file exists. Emits a PHP warning otherwise.
4053          *
4054          * @since 1.27
4055          * @param string $remotePathPrefix URL path prefix that points to $localPath
4056          * @param string $localPath File directory exposed at $remotePath
4057          * @param string $file Path to target file relative to $localPath
4058          * @return string URL
4059          */
4060         public static function transformFilePath( $remotePathPrefix, $localPath, $file ) {
4061                 $hash = md5_file( "$localPath/$file" );
4062                 if ( $hash === false ) {
4063                         wfLogWarning( __METHOD__ . ": Failed to hash $localPath/$file" );
4064                         $hash = '';
4065                 }
4066                 return "$remotePathPrefix/$file?" . substr( $hash, 0, 5 );
4067         }
4068
4069         /**
4070          * Transform "media" attribute based on request parameters
4071          *
4072          * @param string $media Current value of the "media" attribute
4073          * @return string Modified value of the "media" attribute, or null to skip
4074          * this stylesheet
4075          */
4076         public static function transformCssMedia( $media ) {
4077                 global $wgRequest;
4078
4079                 // https://www.w3.org/TR/css3-mediaqueries/#syntax
4080                 $screenMediaQueryRegex = '/^(?:only\s+)?screen\b/i';
4081
4082                 // Switch in on-screen display for media testing
4083                 $switches = [
4084                         'printable' => 'print',
4085                         'handheld' => 'handheld',
4086                 ];
4087                 foreach ( $switches as $switch => $targetMedia ) {
4088                         if ( $wgRequest->getBool( $switch ) ) {
4089                                 if ( $media == $targetMedia ) {
4090                                         $media = '';
4091                                 } elseif ( preg_match( $screenMediaQueryRegex, $media ) === 1 ) {
4092                                         /* This regex will not attempt to understand a comma-separated media_query_list
4093                                          *
4094                                          * Example supported values for $media:
4095                                          * 'screen', 'only screen', 'screen and (min-width: 982px)' ),
4096                                          * Example NOT supported value for $media:
4097                                          * '3d-glasses, screen, print and resolution > 90dpi'
4098                                          *
4099                                          * If it's a print request, we never want any kind of screen stylesheets
4100                                          * If it's a handheld request (currently the only other choice with a switch),
4101                                          * we don't want simple 'screen' but we might want screen queries that
4102                                          * have a max-width or something, so we'll pass all others on and let the
4103                                          * client do the query.
4104                                          */
4105                                         if ( $targetMedia == 'print' || $media == 'screen' ) {
4106                                                 return null;
4107                                         }
4108                                 }
4109                         }
4110                 }
4111
4112                 return $media;
4113         }
4114
4115         /**
4116          * Add a wikitext-formatted message to the output.
4117          * This is equivalent to:
4118          *
4119          *    $wgOut->addWikiText( wfMessage( ... )->plain() )
4120          */
4121         public function addWikiMsg( /*...*/ ) {
4122                 $args = func_get_args();
4123                 $name = array_shift( $args );
4124                 $this->addWikiMsgArray( $name, $args );
4125         }
4126
4127         /**
4128          * Add a wikitext-formatted message to the output.
4129          * Like addWikiMsg() except the parameters are taken as an array
4130          * instead of a variable argument list.
4131          *
4132          * @param string $name
4133          * @param array $args
4134          */
4135         public function addWikiMsgArray( $name, $args ) {
4136                 $this->addHTML( $this->msg( $name, $args )->parseAsBlock() );
4137         }
4138
4139         /**
4140          * This function takes a number of message/argument specifications, wraps them in
4141          * some overall structure, and then parses the result and adds it to the output.
4142          *
4143          * In the $wrap, $1 is replaced with the first message, $2 with the second,
4144          * and so on. The subsequent arguments may be either
4145          * 1) strings, in which case they are message names, or
4146          * 2) arrays, in which case, within each array, the first element is the message
4147          *    name, and subsequent elements are the parameters to that message.
4148          *
4149          * Don't use this for messages that are not in the user's interface language.
4150          *
4151          * For example:
4152          *
4153          *     $wgOut->wrapWikiMsg( "<div class='error'>\n$1\n</div>", 'some-error' );
4154          *
4155          * Is equivalent to:
4156          *
4157          *     $wgOut->addWikiTextAsInterface( "<div class='error'>\n"
4158          *         . wfMessage( 'some-error' )->plain() . "\n</div>" );
4159          *
4160          * The newline after the opening div is needed in some wikitext. See T21226.
4161          *
4162          * @param string $wrap
4163          */
4164         public function wrapWikiMsg( $wrap /*, ...*/ ) {
4165                 $msgSpecs = func_get_args();
4166                 array_shift( $msgSpecs );
4167                 $msgSpecs = array_values( $msgSpecs );
4168                 $s = $wrap;
4169                 foreach ( $msgSpecs as $n => $spec ) {
4170                         if ( is_array( $spec ) ) {
4171                                 $args = $spec;
4172                                 $name = array_shift( $args );
4173                                 if ( isset( $args['options'] ) ) {
4174                                         unset( $args['options'] );
4175                                         wfDeprecated(
4176                                                 'Adding "options" to ' . __METHOD__ . ' is no longer supported',
4177                                                 '1.20'
4178                                         );
4179                                 }
4180                         } else {
4181                                 $args = [];
4182                                 $name = $spec;
4183                         }
4184                         $s = str_replace( '$' . ( $n + 1 ), $this->msg( $name, $args )->plain(), $s );
4185                 }
4186                 $this->addWikiTextAsInterface( $s );
4187         }
4188
4189         /**
4190          * Whether the output has a table of contents
4191          * @return bool
4192          * @since 1.22
4193          */
4194         public function isTOCEnabled() {
4195                 return $this->mEnableTOC;
4196         }
4197
4198         /**
4199          * Enables/disables section edit links, doesn't override __NOEDITSECTION__
4200          * @param bool $flag
4201          * @since 1.23
4202          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
4203          */
4204         public function enableSectionEditLinks( $flag = true ) {
4205                 wfDeprecated( __METHOD__, '1.31' );
4206         }
4207
4208         /**
4209          * @return bool
4210          * @since 1.23
4211          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
4212          */
4213         public function sectionEditLinksEnabled() {
4214                 wfDeprecated( __METHOD__, '1.31' );
4215                 return true;
4216         }
4217
4218         /**
4219          * Helper function to setup the PHP implementation of OOUI to use in this request.
4220          *
4221          * @since 1.26
4222          * @param string $skinName The Skin name to determine the correct OOUI theme
4223          * @param string $dir Language direction
4224          */
4225         public static function setupOOUI( $skinName = 'default', $dir = 'ltr' ) {
4226                 $themes = ResourceLoaderOOUIModule::getSkinThemeMap();
4227                 $theme = $themes[$skinName] ?? $themes['default'];
4228                 // For example, 'OOUI\WikimediaUITheme'.
4229                 $themeClass = "OOUI\\{$theme}Theme";
4230                 OOUI\Theme::setSingleton( new $themeClass() );
4231                 OOUI\Element::setDefaultDir( $dir );
4232         }
4233
4234         /**
4235          * Add ResourceLoader module styles for OOUI and set up the PHP implementation of it for use with
4236          * MediaWiki and this OutputPage instance.
4237          *
4238          * @since 1.25
4239          */
4240         public function enableOOUI() {
4241                 self::setupOOUI(
4242                         strtolower( $this->getSkin()->getSkinName() ),
4243                         $this->getLanguage()->getDir()
4244                 );
4245                 $this->addModuleStyles( [
4246                         'oojs-ui-core.styles',
4247                         'oojs-ui.styles.indicators',
4248                         'oojs-ui.styles.textures',
4249                         'mediawiki.widgets.styles',
4250                         'oojs-ui.styles.icons-content',
4251                         'oojs-ui.styles.icons-alerts',
4252                         'oojs-ui.styles.icons-interactions',
4253                 ] );
4254         }
4255
4256         /**
4257          * Get (and set if not yet set) the CSP nonce.
4258          *
4259          * This value needs to be included in any <script> tags on the
4260          * page.
4261          *
4262          * @return string|bool Nonce or false to mean don't output nonce
4263          * @since 1.32
4264          */
4265         public function getCSPNonce() {
4266                 if ( !ContentSecurityPolicy::isNonceRequired( $this->getConfig() ) ) {
4267                         return false;
4268                 }
4269                 if ( $this->CSPNonce === null ) {
4270                         // XXX It might be expensive to generate randomness
4271                         // on every request, on Windows.
4272                         $rand = random_bytes( 15 );
4273                         $this->CSPNonce = base64_encode( $rand );
4274                 }
4275                 return $this->CSPNonce;
4276         }
4277
4278 }