includes/OutputPage.php

   1 <?php
   2 /**
   3  * Preparation for the final page rendering.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 use MediaWiki\Linker\LinkTarget;
  24 use MediaWiki\Logger\LoggerFactory;
  25 use MediaWiki\MediaWikiServices;
  26 use MediaWiki\Session\SessionManager;
  27 use Wikimedia\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 Should be private - has getter and setter. Contains
  58          *   the HTML title */
  59         public $mPagetitle = '';
  60
  61         /**
  62          * @var string Contains all of the "<body>" content. Should be private we
  63          *   got set/get accessors and the append() method.
  64          */
  65         public $mBodytext = '';
  66
  67         /** @var string Stores contents of "<title>" tag */
  68         private $mHTMLtitle = '';
  69
  70         /**
  71          * @var bool Is the displayed content related to the source of the
  72          *   corresponding wiki article.
  73          */
  74         private $mIsarticle = false;
  75
  76         /** @var bool Stores "article flag" toggle. */
  77         private $mIsArticleRelated = true;
  78
  79         /**
  80          * @var bool We have to set isPrintable(). Some pages should
  81          * never be printed (ex: redirections).
  82          */
  83         private $mPrintable = false;
  84
  85         /**
  86          * @var array Contains the page subtitle. Special pages usually have some
  87          *   links here. Don't confuse with site subtitle added by skins.
  88          */
  89         private $mSubtitle = [];
  90
  91         /** @var string */
  92         public $mRedirect = '';
  93
  94         /** @var int */
  95         protected $mStatusCode;
  96
  97         /**
  98          * @var string Used for sending cache control.
  99          *   The whole caching system should probably be moved into its own class.
 100          */
 101         protected $mLastModified = '';
 102
 103         /** @var array */
 104         protected $mCategoryLinks = [];
 105
 106         /** @var array */
 107         protected $mCategories = [
 108                 'hidden' => [],
 109                 'normal' => [],
 110         ];
 111
 112         /** @var array */
 113         protected $mIndicators = [];
 114
 115         /** @var array Array of Interwiki Prefixed (non DB key) Titles (e.g. 'fr:Test page') */
 116         private $mLanguageLinks = [];
 117
 118         /**
 119          * Used for JavaScript (predates ResourceLoader)
 120          * @todo We should split JS / CSS.
 121          * mScripts content is inserted as is in "<head>" by Skin. This might
 122          * contain either a link to a stylesheet or inline CSS.
 123          */
 124         private $mScripts = '';
 125
 126         /** @var string Inline CSS styles. Use addInlineStyle() sparingly */
 127         protected $mInlineStyles = '';
 128
 129         /**
 130          * @var string Used by skin template.
 131          * Example: $tpl->set( 'displaytitle', $out->mPageLinkTitle );
 132          */
 133         public $mPageLinkTitle = '';
 134
 135         /** @var array Array of elements in "<head>". Parser might add its own headers! */
 136         protected $mHeadItems = [];
 137
 138         /** @var array Additional <body> classes; there are also <body> classes from other sources */
 139         protected $mAdditionalBodyClasses = [];
 140
 141         /** @var array */
 142         protected $mModules = [];
 143
 144         /** @var array */
 145         protected $mModuleScripts = [];
 146
 147         /** @var array */
 148         protected $mModuleStyles = [];
 149
 150         /** @var ResourceLoader */
 151         protected $mResourceLoader;
 152
 153         /** @var ResourceLoaderClientHtml */
 154         private $rlClient;
 155
 156         /** @var ResourceLoaderContext */
 157         private $rlClientContext;
 158
 159         /** @var array */
 160         private $rlExemptStyleModules;
 161
 162         /** @var array */
 163         protected $mJsConfigVars = [];
 164
 165         /** @var array */
 166         protected $mTemplateIds = [];
 167
 168         /** @var array */
 169         protected $mImageTimeKeys = [];
 170
 171         /** @var string */
 172         public $mRedirectCode = '';
 173
 174         protected $mFeedLinksAppendQuery = null;
 175
 176         /** @var array
 177          * What level of 'untrustworthiness' is allowed in CSS/JS modules loaded on this page?
 178          * @see ResourceLoaderModule::$origin
 179          * ResourceLoaderModule::ORIGIN_ALL is assumed unless overridden;
 180          */
 181         protected $mAllowedModules = [
 182                 ResourceLoaderModule::TYPE_COMBINED => ResourceLoaderModule::ORIGIN_ALL,
 183         ];
 184
 185         /** @var bool Whether output is disabled.  If this is true, the 'output' method will do nothing. */
 186         protected $mDoNothing = false;
 187
 188         // Parser related.
 189
 190         /** @var int */
 191         protected $mContainsNewMagic = 0;
 192
 193         /**
 194          * lazy initialised, use parserOptions()
 195          * @var ParserOptions
 196          */
 197         protected $mParserOptions = null;
 198
 199         /**
 200          * Handles the Atom / RSS links.
 201          * We probably only support Atom in 2011.
 202          * @see $wgAdvertisedFeedTypes
 203          */
 204         private $mFeedLinks = [];
 205
 206         // Gwicke work on squid caching? Roughly from 2003.
 207         protected $mEnableClientCache = true;
 208
 209         /** @var bool Flag if output should only contain the body of the article. */
 210         private $mArticleBodyOnly = false;
 211
 212         /** @var bool */
 213         protected $mNewSectionLink = false;
 214
 215         /** @var bool */
 216         protected $mHideNewSectionLink = false;
 217
 218         /**
 219          * @var bool Comes from the parser. This was probably made to load CSS/JS
 220          * only if we had "<gallery>". Used directly in CategoryPage.php.
 221          * Looks like ResourceLoader can replace this.
 222          */
 223         public $mNoGallery = false;
 224
 225         /** @var string */
 226         private $mPageTitleActionText = '';
 227
 228         /** @var int Cache stuff. Looks like mEnableClientCache */
 229         protected $mCdnMaxage = 0;
 230         /** @var int Upper limit on mCdnMaxage */
 231         protected $mCdnMaxageLimit = INF;
 232
 233         /**
 234          * @var bool Controls if anti-clickjacking / frame-breaking headers will
 235          * be sent. This should be done for pages where edit actions are possible.
 236          * Setters: $this->preventClickjacking() and $this->allowClickjacking().
 237          */
 238         protected $mPreventClickjacking = true;
 239
 240         /** @var int To include the variable {{REVISIONID}} */
 241         private $mRevisionId = null;
 242
 243         /** @var string */
 244         private $mRevisionTimestamp = null;
 245
 246         /** @var array */
 247         protected $mFileVersion = null;
 248
 249         /**
 250          * @var array An array of stylesheet filenames (relative from skins path),
 251          * with options for CSS media, IE conditions, and RTL/LTR direction.
 252          * For internal use; add settings in the skin via $this->addStyle()
 253          *
 254          * Style again! This seems like a code duplication since we already have
 255          * mStyles. This is what makes Open Source amazing.
 256          */
 257         protected $styles = [];
 258
 259         private $mIndexPolicy = 'index';
 260         private $mFollowPolicy = 'follow';
 261         private $mVaryHeader = [
 262                 'Accept-Encoding' => [ 'match=gzip' ],
 263         ];
 264
 265         /**
 266          * If the current page was reached through a redirect, $mRedirectedFrom contains the Title
 267          * of the redirect.
 268          *
 269          * @var Title
 270          */
 271         private $mRedirectedFrom = null;
 272
 273         /**
 274          * Additional key => value data
 275          */
 276         private $mProperties = [];
 277
 278         /**
 279          * @var string|null ResourceLoader target for load.php links. If null, will be omitted
 280          */
 281         private $mTarget = null;
 282
 283         /**
 284          * @var bool Whether parser output contains a table of contents
 285          */
 286         private $mEnableTOC = false;
 287
 288         /**
 289          * @var string|null The URL to send in a <link> element with rel=license
 290          */
 291         private $copyrightUrl;
 292
 293         /** @var array Profiling data */
 294         private $limitReportJSData = [];
 295
 296         /** @var array Map Title to Content */
 297         private $contentOverrides = [];
 298
 299         /** @var callable[] */
 300         private $contentOverrideCallbacks = [];
 301
 302         /**
 303          * Link: header contents
 304          */
 305         private $mLinkHeader = [];
 306
 307         /**
 308          * @var string The nonce for Content-Security-Policy
 309          */
 310         private $CSPNonce;
 311
 312         /**
 313          * Constructor for OutputPage. This should not be called directly.
 314          * Instead a new RequestContext should be created and it will implicitly create
 315          * a OutputPage tied to that context.
 316          * @param IContextSource $context
 317          */
 318         function __construct( IContextSource $context ) {
 319                 $this->setContext( $context );
 320         }
 321
 322         /**
 323          * Redirect to $url rather than displaying the normal page
 324          *
 325          * @param string $url
 326          * @param string $responsecode HTTP status code
 327          */
 328         public function redirect( $url, $responsecode = '302' ) {
 329                 # Strip newlines as a paranoia check for header injection in PHP<5.1.2
 330                 $this->mRedirect = str_replace( "\n", '', $url );
 331                 $this->mRedirectCode = $responsecode;
 332         }
 333
 334         /**
 335          * Get the URL to redirect to, or an empty string if not redirect URL set
 336          *
 337          * @return string
 338          */
 339         public function getRedirect() {
 340                 return $this->mRedirect;
 341         }
 342
 343         /**
 344          * Set the copyright URL to send with the output.
 345          * Empty string to omit, null to reset.
 346          *
 347          * @since 1.26
 348          *
 349          * @param string|null $url
 350          */
 351         public function setCopyrightUrl( $url ) {
 352                 $this->copyrightUrl = $url;
 353         }
 354
 355         /**
 356          * Set the HTTP status code to send with the output.
 357          *
 358          * @param int $statusCode
 359          */
 360         public function setStatusCode( $statusCode ) {
 361                 $this->mStatusCode = $statusCode;
 362         }
 363
 364         /**
 365          * Add a new "<meta>" tag
 366          * To add an http-equiv meta tag, precede the name with "http:"
 367          *
 368          * @param string $name Name of the meta tag
 369          * @param string $val Value of the meta tag
 370          */
 371         function addMeta( $name, $val ) {
 372                 array_push( $this->mMetatags, [ $name, $val ] );
 373         }
 374
 375         /**
 376          * Returns the current <meta> tags
 377          *
 378          * @since 1.25
 379          * @return array
 380          */
 381         public function getMetaTags() {
 382                 return $this->mMetatags;
 383         }
 384
 385         /**
 386          * Add a new \<link\> tag to the page header.
 387          *
 388          * Note: use setCanonicalUrl() for rel=canonical.
 389          *
 390          * @param array $linkarr Associative array of attributes.
 391          */
 392         function addLink( array $linkarr ) {
 393                 array_push( $this->mLinktags, $linkarr );
 394         }
 395
 396         /**
 397          * Returns the current <link> tags
 398          *
 399          * @since 1.25
 400          * @return array
 401          */
 402         public function getLinkTags() {
 403                 return $this->mLinktags;
 404         }
 405
 406         /**
 407          * Add a new \<link\> with "rel" attribute set to "meta"
 408          *
 409          * @param array $linkarr Associative array mapping attribute names to their
 410          *                 values, both keys and values will be escaped, and the
 411          *                 "rel" attribute will be automatically added
 412          */
 413         function addMetadataLink( array $linkarr ) {
 414                 $linkarr['rel'] = $this->getMetadataAttribute();
 415                 $this->addLink( $linkarr );
 416         }
 417
 418         /**
 419          * Set the URL to be used for the <link rel=canonical>. This should be used
 420          * in preference to addLink(), to avoid duplicate link tags.
 421          * @param string $url
 422          */
 423         function setCanonicalUrl( $url ) {
 424                 $this->mCanonicalUrl = $url;
 425         }
 426
 427         /**
 428          * Returns the URL to be used for the <link rel=canonical> if
 429          * one is set.
 430          *
 431          * @since 1.25
 432          * @return bool|string
 433          */
 434         public function getCanonicalUrl() {
 435                 return $this->mCanonicalUrl;
 436         }
 437
 438         /**
 439          * Get the value of the "rel" attribute for metadata links
 440          *
 441          * @return string
 442          */
 443         public function getMetadataAttribute() {
 444                 # note: buggy CC software only reads first "meta" link
 445                 static $haveMeta = false;
 446                 if ( $haveMeta ) {
 447                         return 'alternate meta';
 448                 } else {
 449                         $haveMeta = true;
 450                         return 'meta';
 451                 }
 452         }
 453
 454         /**
 455          * Add raw HTML to the list of scripts (including \<script\> tag, etc.)
 456          * Internal use only. Use OutputPage::addModules() or OutputPage::addJsConfigVars()
 457          * if possible.
 458          *
 459          * @param string $script Raw HTML
 460          */
 461         function addScript( $script ) {
 462                 $this->mScripts .= $script;
 463         }
 464
 465         /**
 466          * Add a JavaScript file to be loaded as `<script>` on this page.
 467          *
 468          * Internal use only. Use OutputPage::addModules() if possible.
 469          *
 470          * @param string $file URL to file (absolute path, protocol-relative, or full url)
 471          * @param string $unused Previously used to change the cache-busting query parameter
 472          */
 473         public function addScriptFile( $file, $unused = null ) {
 474                 if ( substr( $file, 0, 1 ) !== '/' && !preg_match( '#^[a-z]*://#i', $file ) ) {
 475                         // This is not an absolute path, protocol-relative url, or full scheme url,
 476                         // presumed to be an old call intended to include a file from /w/skins/common,
 477                         // which doesn't exist anymore as of MediaWiki 1.24 per T71277. Ignore.
 478                         wfDeprecated( __METHOD__, '1.24' );
 479                         return;
 480                 }
 481                 $this->addScript( Html::linkedScript( $file, $this->getCSPNonce() ) );
 482         }
 483
 484         /**
 485          * Add a self-contained script tag with the given contents
 486          * Internal use only. Use OutputPage::addModules() if possible.
 487          *
 488          * @param string $script JavaScript text, no script tags
 489          */
 490         public function addInlineScript( $script ) {
 491                 $this->mScripts .= Html::inlineScript( "\n$script\n", $this->getCSPNonce() ) . "\n";
 492         }
 493
 494         /**
 495          * Filter an array of modules to remove insufficiently trustworthy members, and modules
 496          * which are no longer registered (eg a page is cached before an extension is disabled)
 497          * @param array $modules
 498          * @param string|null $position Unused
 499          * @param string $type
 500          * @return array
 501          */
 502         protected function filterModules( array $modules, $position = null,
 503                 $type = ResourceLoaderModule::TYPE_COMBINED
 504         ) {
 505                 $resourceLoader = $this->getResourceLoader();
 506                 $filteredModules = [];
 507                 foreach ( $modules as $val ) {
 508                         $module = $resourceLoader->getModule( $val );
 509                         if ( $module instanceof ResourceLoaderModule
 510                                 && $module->getOrigin() <= $this->getAllowedModules( $type )
 511                         ) {
 512                                 if ( $this->mTarget && !in_array( $this->mTarget, $module->getTargets() ) ) {
 513                                         $this->warnModuleTargetFilter( $module->getName() );
 514                                         continue;
 515                                 }
 516                                 $filteredModules[] = $val;
 517                         }
 518                 }
 519                 return $filteredModules;
 520         }
 521
 522         private function warnModuleTargetFilter( $moduleName ) {
 523                 static $warnings = [];
 524                 if ( isset( $warnings[$this->mTarget][$moduleName] ) ) {
 525                         return;
 526                 }
 527                 $warnings[$this->mTarget][$moduleName] = true;
 528                 $this->getResourceLoader()->getLogger()->debug(
 529                         'Module "{module}" not loadable on target "{target}".',
 530                         [
 531                                 'module' => $moduleName,
 532                                 'target' => $this->mTarget,
 533                         ]
 534                 );
 535         }
 536
 537         /**
 538          * Get the list of modules to include on this page
 539          *
 540          * @param bool $filter Whether to filter out insufficiently trustworthy modules
 541          * @param string|null $position Unused
 542          * @param string $param
 543          * @param string $type
 544          * @return array Array of module names
 545          */
 546         public function getModules( $filter = false, $position = null, $param = 'mModules',
 547                 $type = ResourceLoaderModule::TYPE_COMBINED
 548         ) {
 549                 $modules = array_values( array_unique( $this->$param ) );
 550                 return $filter
 551                         ? $this->filterModules( $modules, null, $type )
 552                         : $modules;
 553         }
 554
 555         /**
 556          * Load one or more ResourceLoader modules on this page.
 557          *
 558          * @param string|array $modules Module name (string) or array of module names
 559          */
 560         public function addModules( $modules ) {
 561                 $this->mModules = array_merge( $this->mModules, (array)$modules );
 562         }
 563
 564         /**
 565          * Get the list of script-only modules to load on this page.
 566          *
 567          * @param bool $filter
 568          * @param string|null $position Unused
 569          * @return array Array of module names
 570          */
 571         public function getModuleScripts( $filter = false, $position = null ) {
 572                 return $this->getModules( $filter, null, 'mModuleScripts',
 573                         ResourceLoaderModule::TYPE_SCRIPTS
 574                 );
 575         }
 576
 577         /**
 578          * Load the scripts of one or more ResourceLoader modules, on this page.
 579          *
 580          * This method exists purely to provide the legacy behaviour of loading
 581          * a module's scripts in the global scope, and without dependency resolution.
 582          * See <https://phabricator.wikimedia.org/T188689>.
 583          *
 584          * @deprecated since 1.31 Use addModules() instead.
 585          * @param string|array $modules Module name (string) or array of module names
 586          */
 587         public function addModuleScripts( $modules ) {
 588                 $this->mModuleScripts = array_merge( $this->mModuleScripts, (array)$modules );
 589         }
 590
 591         /**
 592          * Get the list of style-only modules to load on this page.
 593          *
 594          * @param bool $filter
 595          * @param string|null $position Unused
 596          * @return array Array of module names
 597          */
 598         public function getModuleStyles( $filter = false, $position = null ) {
 599                 return $this->getModules( $filter, null, 'mModuleStyles',
 600                         ResourceLoaderModule::TYPE_STYLES
 601                 );
 602         }
 603
 604         /**
 605          * Load the styles of one or more ResourceLoader modules on this page.
 606          *
 607          * Module styles added through this function will be loaded as a stylesheet,
 608          * using a standard `<link rel=stylesheet>` HTML tag, rather than as a combined
 609          * Javascript and CSS package. Thus, they will even load when JavaScript is disabled.
 610          *
 611          * @param string|array $modules Module name (string) or array of module names
 612          */
 613         public function addModuleStyles( $modules ) {
 614                 $this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
 615         }
 616
 617         /**
 618          * @return null|string ResourceLoader target
 619          */
 620         public function getTarget() {
 621                 return $this->mTarget;
 622         }
 623
 624         /**
 625          * Sets ResourceLoader target for load.php links. If null, will be omitted
 626          *
 627          * @param string|null $target
 628          */
 629         public function setTarget( $target ) {
 630                 $this->mTarget = $target;
 631         }
 632
 633         /**
 634          * Add a mapping from a LinkTarget to a Content, for things like page preview.
 635          * @see self::addContentOverrideCallback()
 636          * @since 1.32
 637          * @param LinkTarget $target
 638          * @param Content $content
 639          */
 640         public function addContentOverride( LinkTarget $target, Content $content ) {
 641                 if ( !$this->contentOverrides ) {
 642                         // Register a callback for $this->contentOverrides on the first call
 643                         $this->addContentOverrideCallback( function ( LinkTarget $target ) {
 644                                 $key = $target->getNamespace() . ':' . $target->getDBkey();
 645                                 return isset( $this->contentOverrides[$key] )
 646                                         ? $this->contentOverrides[$key]
 647                                         : null;
 648                         } );
 649                 }
 650
 651                 $key = $target->getNamespace() . ':' . $target->getDBkey();
 652                 $this->contentOverrides[$key] = $content;
 653         }
 654
 655         /**
 656          * Add a callback for mapping from a Title to a Content object, for things
 657          * like page preview.
 658          * @see ResourceLoaderContext::getContentOverrideCallback()
 659          * @since 1.32
 660          * @param callable $callback
 661          */
 662         public function addContentOverrideCallback( callable $callback ) {
 663                 $this->contentOverrideCallbacks[] = $callback;
 664         }
 665
 666         /**
 667          * Get an array of head items
 668          *
 669          * @return array
 670          */
 671         function getHeadItemsArray() {
 672                 return $this->mHeadItems;
 673         }
 674
 675         /**
 676          * Add or replace a head item to the output
 677          *
 678          * Whenever possible, use more specific options like ResourceLoader modules,
 679          * OutputPage::addLink(), OutputPage::addMetaLink() and OutputPage::addFeedLink()
 680          * Fallback options for those are: OutputPage::addStyle, OutputPage::addScript(),
 681          * OutputPage::addInlineScript() and OutputPage::addInlineStyle()
 682          * This would be your very LAST fallback.
 683          *
 684          * @param string $name Item name
 685          * @param string $value Raw HTML
 686          */
 687         public function addHeadItem( $name, $value ) {
 688                 $this->mHeadItems[$name] = $value;
 689         }
 690
 691         /**
 692          * Add one or more head items to the output
 693          *
 694          * @since 1.28
 695          * @param string|string[] $values Raw HTML
 696          */
 697         public function addHeadItems( $values ) {
 698                 $this->mHeadItems = array_merge( $this->mHeadItems, (array)$values );
 699         }
 700
 701         /**
 702          * Check if the header item $name is already set
 703          *
 704          * @param string $name Item name
 705          * @return bool
 706          */
 707         public function hasHeadItem( $name ) {
 708                 return isset( $this->mHeadItems[$name] );
 709         }
 710
 711         /**
 712          * Add a class to the <body> element
 713          *
 714          * @since 1.30
 715          * @param string|string[] $classes One or more classes to add
 716          */
 717         public function addBodyClasses( $classes ) {
 718                 $this->mAdditionalBodyClasses = array_merge( $this->mAdditionalBodyClasses, (array)$classes );
 719         }
 720
 721         /**
 722          * Set whether the output should only contain the body of the article,
 723          * without any skin, sidebar, etc.
 724          * Used e.g. when calling with "action=render".
 725          *
 726          * @param bool $only Whether to output only the body of the article
 727          */
 728         public function setArticleBodyOnly( $only ) {
 729                 $this->mArticleBodyOnly = $only;
 730         }
 731
 732         /**
 733          * Return whether the output will contain only the body of the article
 734          *
 735          * @return bool
 736          */
 737         public function getArticleBodyOnly() {
 738                 return $this->mArticleBodyOnly;
 739         }
 740
 741         /**
 742          * Set an additional output property
 743          * @since 1.21
 744          *
 745          * @param string $name
 746          * @param mixed $value
 747          */
 748         public function setProperty( $name, $value ) {
 749                 $this->mProperties[$name] = $value;
 750         }
 751
 752         /**
 753          * Get an additional output property
 754          * @since 1.21
 755          *
 756          * @param string $name
 757          * @return mixed Property value or null if not found
 758          */
 759         public function getProperty( $name ) {
 760                 if ( isset( $this->mProperties[$name] ) ) {
 761                         return $this->mProperties[$name];
 762                 } else {
 763                         return null;
 764                 }
 765         }
 766
 767         /**
 768          * checkLastModified tells the client to use the client-cached page if
 769          * possible. If successful, the OutputPage is disabled so that
 770          * any future call to OutputPage->output() have no effect.
 771          *
 772          * Side effect: sets mLastModified for Last-Modified header
 773          *
 774          * @param string $timestamp
 775          *
 776          * @return bool True if cache-ok headers was sent.
 777          */
 778         public function checkLastModified( $timestamp ) {
 779                 if ( !$timestamp || $timestamp == '19700101000000' ) {
 780                         wfDebug( __METHOD__ . ": CACHE DISABLED, NO TIMESTAMP\n" );
 781                         return false;
 782                 }
 783                 $config = $this->getConfig();
 784                 if ( !$config->get( 'CachePages' ) ) {
 785                         wfDebug( __METHOD__ . ": CACHE DISABLED\n" );
 786                         return false;
 787                 }
 788
 789                 $timestamp = wfTimestamp( TS_MW, $timestamp );
 790                 $modifiedTimes = [
 791                         'page' => $timestamp,
 792                         'user' => $this->getUser()->getTouched(),
 793                         'epoch' => $config->get( 'CacheEpoch' )
 794                 ];
 795                 if ( $config->get( 'UseSquid' ) ) {
 796                         $modifiedTimes['sepoch'] = wfTimestamp( TS_MW, $this->getCdnCacheEpoch(
 797                                 time(),
 798                                 $config->get( 'SquidMaxage' )
 799                         ) );
 800                 }
 801                 Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this ] );
 802
 803                 $maxModified = max( $modifiedTimes );
 804                 $this->mLastModified = wfTimestamp( TS_RFC2822, $maxModified );
 805
 806                 $clientHeader = $this->getRequest()->getHeader( 'If-Modified-Since' );
 807                 if ( $clientHeader === false ) {
 808                         wfDebug( __METHOD__ . ": client did not send If-Modified-Since header", 'private' );
 809                         return false;
 810                 }
 811
 812                 # IE sends sizes after the date like this:
 813                 # Wed, 20 Aug 2003 06:51:19 GMT; length=5202
 814                 # this breaks strtotime().
 815                 $clientHeader = preg_replace( '/;.*$/', '', $clientHeader );
 816
 817                 Wikimedia\suppressWarnings(); // E_STRICT system time bitching
 818                 $clientHeaderTime = strtotime( $clientHeader );
 819                 Wikimedia\restoreWarnings();
 820                 if ( !$clientHeaderTime ) {
 821                         wfDebug( __METHOD__
 822                                 . ": unable to parse the client's If-Modified-Since header: $clientHeader\n" );
 823                         return false;
 824                 }
 825                 $clientHeaderTime = wfTimestamp( TS_MW, $clientHeaderTime );
 826
 827                 # Make debug info
 828                 $info = '';
 829                 foreach ( $modifiedTimes as $name => $value ) {
 830                         if ( $info !== '' ) {
 831                                 $info .= ', ';
 832                         }
 833                         $info .= "$name=" . wfTimestamp( TS_ISO_8601, $value );
 834                 }
 835
 836                 wfDebug( __METHOD__ . ": client sent If-Modified-Since: " .
 837                         wfTimestamp( TS_ISO_8601, $clientHeaderTime ), 'private' );
 838                 wfDebug( __METHOD__ . ": effective Last-Modified: " .
 839                         wfTimestamp( TS_ISO_8601, $maxModified ), 'private' );
 840                 if ( $clientHeaderTime < $maxModified ) {
 841                         wfDebug( __METHOD__ . ": STALE, $info", 'private' );
 842                         return false;
 843                 }
 844
 845                 # Not modified
 846                 # Give a 304 Not Modified response code and disable body output
 847                 wfDebug( __METHOD__ . ": NOT MODIFIED, $info", 'private' );
 848                 ini_set( 'zlib.output_compression', 0 );
 849                 $this->getRequest()->response()->statusHeader( 304 );
 850                 $this->sendCacheControl();
 851                 $this->disable();
 852
 853                 // Don't output a compressed blob when using ob_gzhandler;
 854                 // it's technically against HTTP spec and seems to confuse
 855                 // Firefox when the response gets split over two packets.
 856                 wfClearOutputBuffers();
 857
 858                 return true;
 859         }
 860
 861         /**
 862          * @param int $reqTime Time of request (eg. now)
 863          * @param int $maxAge Cache TTL in seconds
 864          * @return int Timestamp
 865          */
 866         private function getCdnCacheEpoch( $reqTime, $maxAge ) {
 867                 // Ensure Last-Modified is never more than (wgSquidMaxage) in the past,
 868                 // because even if the wiki page content hasn't changed since, static
 869                 // resources may have changed (skin HTML, interface messages, urls, etc.)
 870                 // and must roll-over in a timely manner (T46570)
 871                 return $reqTime - $maxAge;
 872         }
 873
 874         /**
 875          * Override the last modified timestamp
 876          *
 877          * @param string $timestamp New timestamp, in a format readable by
 878          *        wfTimestamp()
 879          */
 880         public function setLastModified( $timestamp ) {
 881                 $this->mLastModified = wfTimestamp( TS_RFC2822, $timestamp );
 882         }
 883
 884         /**
 885          * Set the robot policy for the page: <http://www.robotstxt.org/meta.html>
 886          *
 887          * @param string $policy The literal string to output as the contents of
 888          *   the meta tag.  Will be parsed according to the spec and output in
 889          *   standardized form.
 890          * @return null
 891          */
 892         public function setRobotPolicy( $policy ) {
 893                 $policy = Article::formatRobotPolicy( $policy );
 894
 895                 if ( isset( $policy['index'] ) ) {
 896                         $this->setIndexPolicy( $policy['index'] );
 897                 }
 898                 if ( isset( $policy['follow'] ) ) {
 899                         $this->setFollowPolicy( $policy['follow'] );
 900                 }
 901         }
 902
 903         /**
 904          * Set the index policy for the page, but leave the follow policy un-
 905          * touched.
 906          *
 907          * @param string $policy Either 'index' or 'noindex'.
 908          * @return null
 909          */
 910         public function setIndexPolicy( $policy ) {
 911                 $policy = trim( $policy );
 912                 if ( in_array( $policy, [ 'index', 'noindex' ] ) ) {
 913                         $this->mIndexPolicy = $policy;
 914                 }
 915         }
 916
 917         /**
 918          * Set the follow policy for the page, but leave the index policy un-
 919          * touched.
 920          *
 921          * @param string $policy Either 'follow' or 'nofollow'.
 922          * @return null
 923          */
 924         public function setFollowPolicy( $policy ) {
 925                 $policy = trim( $policy );
 926                 if ( in_array( $policy, [ 'follow', 'nofollow' ] ) ) {
 927                         $this->mFollowPolicy = $policy;
 928                 }
 929         }
 930
 931         /**
 932          * Set the new value of the "action text", this will be added to the
 933          * "HTML title", separated from it with " - ".
 934          *
 935          * @param string $text New value of the "action text"
 936          */
 937         public function setPageTitleActionText( $text ) {
 938                 $this->mPageTitleActionText = $text;
 939         }
 940
 941         /**
 942          * Get the value of the "action text"
 943          *
 944          * @return string
 945          */
 946         public function getPageTitleActionText() {
 947                 return $this->mPageTitleActionText;
 948         }
 949
 950         /**
 951          * "HTML title" means the contents of "<title>".
 952          * It is stored as plain, unescaped text and will be run through htmlspecialchars in the skin file.
 953          *
 954          * @param string|Message $name
 955          */
 956         public function setHTMLTitle( $name ) {
 957                 if ( $name instanceof Message ) {
 958                         $this->mHTMLtitle = $name->setContext( $this->getContext() )->text();
 959                 } else {
 960                         $this->mHTMLtitle = $name;
 961                 }
 962         }
 963
 964         /**
 965          * Return the "HTML title", i.e. the content of the "<title>" tag.
 966          *
 967          * @return string
 968          */
 969         public function getHTMLTitle() {
 970                 return $this->mHTMLtitle;
 971         }
 972
 973         /**
 974          * Set $mRedirectedFrom, the Title of the page which redirected us to the current page.
 975          *
 976          * @param Title $t
 977          */
 978         public function setRedirectedFrom( $t ) {
 979                 $this->mRedirectedFrom = $t;
 980         }
 981
 982         /**
 983          * "Page title" means the contents of \<h1\>. It is stored as a valid HTML
 984          * fragment. This function allows good tags like \<sup\> in the \<h1\> tag,
 985          * but not bad tags like \<script\>. This function automatically sets
 986          * \<title\> to the same content as \<h1\> but with all tags removed. Bad
 987          * tags that were escaped in \<h1\> will still be escaped in \<title\>, and
 988          * good tags like \<i\> will be dropped entirely.
 989          *
 990          * @param string|Message $name
 991          */
 992         public function setPageTitle( $name ) {
 993                 if ( $name instanceof Message ) {
 994                         $name = $name->setContext( $this->getContext() )->text();
 995                 }
 996
 997                 # change "<script>foo&bar</script>" to "&lt;script&gt;foo&amp;bar&lt;/script&gt;"
 998                 # but leave "<i>foobar</i>" alone
 999                 $nameWithTags = Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $name ) );
1000                 $this->mPagetitle = $nameWithTags;
1001
1002                 # change "<i>foo&amp;bar</i>" to "foo&bar"
1003                 $this->setHTMLTitle(
1004                         $this->msg( 'pagetitle' )->rawParams( Sanitizer::stripAllTags( $nameWithTags ) )
1005                                 ->inContentLanguage()
1006                 );
1007         }
1008
1009         /**
1010          * Return the "page title", i.e. the content of the \<h1\> tag.
1011          *
1012          * @return string
1013          */
1014         public function getPageTitle() {
1015                 return $this->mPagetitle;
1016         }
1017
1018         /**
1019          * Set the Title object to use
1020          *
1021          * @param Title $t
1022          */
1023         public function setTitle( Title $t ) {
1024                 $this->getContext()->setTitle( $t );
1025         }
1026
1027         /**
1028          * Replace the subtitle with $str
1029          *
1030          * @param string|Message $str New value of the subtitle. String should be safe HTML.
1031          */
1032         public function setSubtitle( $str ) {
1033                 $this->clearSubtitle();
1034                 $this->addSubtitle( $str );
1035         }
1036
1037         /**
1038          * Add $str to the subtitle
1039          *
1040          * @param string|Message $str String or Message to add to the subtitle. String should be safe HTML.
1041          */
1042         public function addSubtitle( $str ) {
1043                 if ( $str instanceof Message ) {
1044                         $this->mSubtitle[] = $str->setContext( $this->getContext() )->parse();
1045                 } else {
1046                         $this->mSubtitle[] = $str;
1047                 }
1048         }
1049
1050         /**
1051          * Build message object for a subtitle containing a backlink to a page
1052          *
1053          * @param Title $title Title to link to
1054          * @param array $query Array of additional parameters to include in the link
1055          * @return Message
1056          * @since 1.25
1057          */
1058         public static function buildBacklinkSubtitle( Title $title, $query = [] ) {
1059                 if ( $title->isRedirect() ) {
1060                         $query['redirect'] = 'no';
1061                 }
1062                 $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1063                 return wfMessage( 'backlinksubtitle' )
1064                         ->rawParams( $linkRenderer->makeLink( $title, null, [], $query ) );
1065         }
1066
1067         /**
1068          * Add a subtitle containing a backlink to a page
1069          *
1070          * @param Title $title Title to link to
1071          * @param array $query Array of additional parameters to include in the link
1072          */
1073         public function addBacklinkSubtitle( Title $title, $query = [] ) {
1074                 $this->addSubtitle( self::buildBacklinkSubtitle( $title, $query ) );
1075         }
1076
1077         /**
1078          * Clear the subtitles
1079          */
1080         public function clearSubtitle() {
1081                 $this->mSubtitle = [];
1082         }
1083
1084         /**
1085          * Get the subtitle
1086          *
1087          * @return string
1088          */
1089         public function getSubtitle() {
1090                 return implode( "<br />\n\t\t\t\t", $this->mSubtitle );
1091         }
1092
1093         /**
1094          * Set the page as printable, i.e. it'll be displayed with all
1095          * print styles included
1096          */
1097         public function setPrintable() {
1098                 $this->mPrintable = true;
1099         }
1100
1101         /**
1102          * Return whether the page is "printable"
1103          *
1104          * @return bool
1105          */
1106         public function isPrintable() {
1107                 return $this->mPrintable;
1108         }
1109
1110         /**
1111          * Disable output completely, i.e. calling output() will have no effect
1112          */
1113         public function disable() {
1114                 $this->mDoNothing = true;
1115         }
1116
1117         /**
1118          * Return whether the output will be completely disabled
1119          *
1120          * @return bool
1121          */
1122         public function isDisabled() {
1123                 return $this->mDoNothing;
1124         }
1125
1126         /**
1127          * Show an "add new section" link?
1128          *
1129          * @return bool
1130          */
1131         public function showNewSectionLink() {
1132                 return $this->mNewSectionLink;
1133         }
1134
1135         /**
1136          * Forcibly hide the new section link?
1137          *
1138          * @return bool
1139          */
1140         public function forceHideNewSectionLink() {
1141                 return $this->mHideNewSectionLink;
1142         }
1143
1144         /**
1145          * Add or remove feed links in the page header
1146          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1147          * for the new version
1148          * @see addFeedLink()
1149          *
1150          * @param bool $show True: add default feeds, false: remove all feeds
1151          */
1152         public function setSyndicated( $show = true ) {
1153                 if ( $show ) {
1154                         $this->setFeedAppendQuery( false );
1155                 } else {
1156                         $this->mFeedLinks = [];
1157                 }
1158         }
1159
1160         /**
1161          * Add default feeds to the page header
1162          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1163          * for the new version
1164          * @see addFeedLink()
1165          *
1166          * @param string $val Query to append to feed links or false to output
1167          *        default links
1168          */
1169         public function setFeedAppendQuery( $val ) {
1170                 $this->mFeedLinks = [];
1171
1172                 foreach ( $this->getConfig()->get( 'AdvertisedFeedTypes' ) as $type ) {
1173                         $query = "feed=$type";
1174                         if ( is_string( $val ) ) {
1175                                 $query .= '&' . $val;
1176                         }
1177                         $this->mFeedLinks[$type] = $this->getTitle()->getLocalURL( $query );
1178                 }
1179         }
1180
1181         /**
1182          * Add a feed link to the page header
1183          *
1184          * @param string $format Feed type, should be a key of $wgFeedClasses
1185          * @param string $href URL
1186          */
1187         public function addFeedLink( $format, $href ) {
1188                 if ( in_array( $format, $this->getConfig()->get( 'AdvertisedFeedTypes' ) ) ) {
1189                         $this->mFeedLinks[$format] = $href;
1190                 }
1191         }
1192
1193         /**
1194          * Should we output feed links for this page?
1195          * @return bool
1196          */
1197         public function isSyndicated() {
1198                 return count( $this->mFeedLinks ) > 0;
1199         }
1200
1201         /**
1202          * Return URLs for each supported syndication format for this page.
1203          * @return array Associating format keys with URLs
1204          */
1205         public function getSyndicationLinks() {
1206                 return $this->mFeedLinks;
1207         }
1208
1209         /**
1210          * Will currently always return null
1211          *
1212          * @return null
1213          */
1214         public function getFeedAppendQuery() {
1215                 return $this->mFeedLinksAppendQuery;
1216         }
1217
1218         /**
1219          * Set whether the displayed content is related to the source of the
1220          * corresponding article on the wiki
1221          * Setting true will cause the change "article related" toggle to true
1222          *
1223          * @param bool $v
1224          */
1225         public function setArticleFlag( $v ) {
1226                 $this->mIsarticle = $v;
1227                 if ( $v ) {
1228                         $this->mIsArticleRelated = $v;
1229                 }
1230         }
1231
1232         /**
1233          * Return whether the content displayed page is related to the source of
1234          * the corresponding article on the wiki
1235          *
1236          * @return bool
1237          */
1238         public function isArticle() {
1239                 return $this->mIsarticle;
1240         }
1241
1242         /**
1243          * Set whether this page is related an article on the wiki
1244          * Setting false will cause the change of "article flag" toggle to false
1245          *
1246          * @param bool $v
1247          */
1248         public function setArticleRelated( $v ) {
1249                 $this->mIsArticleRelated = $v;
1250                 if ( !$v ) {
1251                         $this->mIsarticle = false;
1252                 }
1253         }
1254
1255         /**
1256          * Return whether this page is related an article on the wiki
1257          *
1258          * @return bool
1259          */
1260         public function isArticleRelated() {
1261                 return $this->mIsArticleRelated;
1262         }
1263
1264         /**
1265          * Add new language links
1266          *
1267          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1268          *                               (e.g. 'fr:Test page')
1269          */
1270         public function addLanguageLinks( array $newLinkArray ) {
1271                 $this->mLanguageLinks += $newLinkArray;
1272         }
1273
1274         /**
1275          * Reset the language links and add new language links
1276          *
1277          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1278          *                               (e.g. 'fr:Test page')
1279          */
1280         public function setLanguageLinks( array $newLinkArray ) {
1281                 $this->mLanguageLinks = $newLinkArray;
1282         }
1283
1284         /**
1285          * Get the list of language links
1286          *
1287          * @return string[] Array of interwiki-prefixed (non DB key) titles (e.g. 'fr:Test page')
1288          */
1289         public function getLanguageLinks() {
1290                 return $this->mLanguageLinks;
1291         }
1292
1293         /**
1294          * Add an array of categories, with names in the keys
1295          *
1296          * @param array $categories Mapping category name => sort key
1297          */
1298         public function addCategoryLinks( array $categories ) {
1299                 global $wgContLang;
1300
1301                 if ( !is_array( $categories ) || count( $categories ) == 0 ) {
1302                         return;
1303                 }
1304
1305                 $res = $this->addCategoryLinksToLBAndGetResult( $categories );
1306
1307                 # Set all the values to 'normal'.
1308                 $categories = array_fill_keys( array_keys( $categories ), 'normal' );
1309
1310                 # Mark hidden categories
1311                 foreach ( $res as $row ) {
1312                         if ( isset( $row->pp_value ) ) {
1313                                 $categories[$row->page_title] = 'hidden';
1314                         }
1315                 }
1316
1317                 // Avoid PHP 7.1 warning of passing $this by reference
1318                 $outputPage = $this;
1319                 # Add the remaining categories to the skin
1320                 if ( Hooks::run(
1321                         'OutputPageMakeCategoryLinks',
1322                         [ &$outputPage, $categories, &$this->mCategoryLinks ] )
1323                 ) {
1324                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1325                         foreach ( $categories as $category => $type ) {
1326                                 // array keys will cast numeric category names to ints, so cast back to string
1327                                 $category = (string)$category;
1328                                 $origcategory = $category;
1329                                 $title = Title::makeTitleSafe( NS_CATEGORY, $category );
1330                                 if ( !$title ) {
1331                                         continue;
1332                                 }
1333                                 $wgContLang->findVariantLink( $category, $title, true );
1334                                 if ( $category != $origcategory && array_key_exists( $category, $categories ) ) {
1335                                         continue;
1336                                 }
1337                                 $text = $wgContLang->convertHtml( $title->getText() );
1338                                 $this->mCategories[$type][] = $title->getText();
1339                                 $this->mCategoryLinks[$type][] = $linkRenderer->makeLink( $title, new HtmlArmor( $text ) );
1340                         }
1341                 }
1342         }
1343
1344         /**
1345          * @param array $categories
1346          * @return bool|ResultWrapper
1347          */
1348         protected function addCategoryLinksToLBAndGetResult( array $categories ) {
1349                 # Add the links to a LinkBatch
1350                 $arr = [ NS_CATEGORY => $categories ];
1351                 $lb = new LinkBatch;
1352                 $lb->setArray( $arr );
1353
1354                 # Fetch existence plus the hiddencat property
1355                 $dbr = wfGetDB( DB_REPLICA );
1356                 $fields = array_merge(
1357                         LinkCache::getSelectFields(),
1358                         [ 'page_namespace', 'page_title', 'pp_value' ]
1359                 );
1360
1361                 $res = $dbr->select( [ 'page', 'page_props' ],
1362                         $fields,
1363                         $lb->constructSet( 'page', $dbr ),
1364                         __METHOD__,
1365                         [],
1366                         [ 'page_props' => [ 'LEFT JOIN', [
1367                                 'pp_propname' => 'hiddencat',
1368                                 'pp_page = page_id'
1369                         ] ] ]
1370                 );
1371
1372                 # Add the results to the link cache
1373                 $lb->addResultToCache( LinkCache::singleton(), $res );
1374
1375                 return $res;
1376         }
1377
1378         /**
1379          * Reset the category links (but not the category list) and add $categories
1380          *
1381          * @param array $categories Mapping category name => sort key
1382          */
1383         public function setCategoryLinks( array $categories ) {
1384                 $this->mCategoryLinks = [];
1385                 $this->addCategoryLinks( $categories );
1386         }
1387
1388         /**
1389          * Get the list of category links, in a 2-D array with the following format:
1390          * $arr[$type][] = $link, where $type is either "normal" or "hidden" (for
1391          * hidden categories) and $link a HTML fragment with a link to the category
1392          * page
1393          *
1394          * @return array
1395          */
1396         public function getCategoryLinks() {
1397                 return $this->mCategoryLinks;
1398         }
1399
1400         /**
1401          * Get the list of category names this page belongs to.
1402          *
1403          * @param string $type The type of categories which should be returned. Possible values:
1404          *  * all: all categories of all types
1405          *  * hidden: only the hidden categories
1406          *  * normal: all categories, except hidden categories
1407          * @return array Array of strings
1408          */
1409         public function getCategories( $type = 'all' ) {
1410                 if ( $type === 'all' ) {
1411                         $allCategories = [];
1412                         foreach ( $this->mCategories as $categories ) {
1413                                 $allCategories = array_merge( $allCategories, $categories );
1414                         }
1415                         return $allCategories;
1416                 }
1417                 if ( !isset( $this->mCategories[$type] ) ) {
1418                         throw new InvalidArgumentException( 'Invalid category type given: ' . $type );
1419                 }
1420                 return $this->mCategories[$type];
1421         }
1422
1423         /**
1424          * Add an array of indicators, with their identifiers as array
1425          * keys and HTML contents as values.
1426          *
1427          * In case of duplicate keys, existing values are overwritten.
1428          *
1429          * @param array $indicators
1430          * @since 1.25
1431          */
1432         public function setIndicators( array $indicators ) {
1433                 $this->mIndicators = $indicators + $this->mIndicators;
1434                 // Keep ordered by key
1435                 ksort( $this->mIndicators );
1436         }
1437
1438         /**
1439          * Get the indicators associated with this page.
1440          *
1441          * The array will be internally ordered by item keys.
1442          *
1443          * @return array Keys: identifiers, values: HTML contents
1444          * @since 1.25
1445          */
1446         public function getIndicators() {
1447                 return $this->mIndicators;
1448         }
1449
1450         /**
1451          * Adds help link with an icon via page indicators.
1452          * Link target can be overridden by a local message containing a wikilink:
1453          * the message key is: lowercase action or special page name + '-helppage'.
1454          * @param string $to Target MediaWiki.org page title or encoded URL.
1455          * @param bool $overrideBaseUrl Whether $url is a full URL, to avoid MW.o.
1456          * @since 1.25
1457          */
1458         public function addHelpLink( $to, $overrideBaseUrl = false ) {
1459                 $this->addModuleStyles( 'mediawiki.helplink' );
1460                 $text = $this->msg( 'helppage-top-gethelp' )->escaped();
1461
1462                 if ( $overrideBaseUrl ) {
1463                         $helpUrl = $to;
1464                 } else {
1465                         $toUrlencoded = wfUrlencode( str_replace( ' ', '_', $to ) );
1466                         $helpUrl = "//www.mediawiki.org/wiki/Special:MyLanguage/$toUrlencoded";
1467                 }
1468
1469                 $link = Html::rawElement(
1470                         'a',
1471                         [
1472                                 'href' => $helpUrl,
1473                                 'target' => '_blank',
1474                                 'class' => 'mw-helplink',
1475                         ],
1476                         $text
1477                 );
1478
1479                 $this->setIndicators( [ 'mw-helplink' => $link ] );
1480         }
1481
1482         /**
1483          * Do not allow scripts which can be modified by wiki users to load on this page;
1484          * only allow scripts bundled with, or generated by, the software.
1485          * Site-wide styles are controlled by a config setting, since they can be
1486          * used to create a custom skin/theme, but not user-specific ones.
1487          *
1488          * @todo this should be given a more accurate name
1489          */
1490         public function disallowUserJs() {
1491                 $this->reduceAllowedModules(
1492                         ResourceLoaderModule::TYPE_SCRIPTS,
1493                         ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
1494                 );
1495
1496                 // Site-wide styles are controlled by a config setting, see T73621
1497                 // for background on why. User styles are never allowed.
1498                 if ( $this->getConfig()->get( 'AllowSiteCSSOnRestrictedPages' ) ) {
1499                         $styleOrigin = ResourceLoaderModule::ORIGIN_USER_SITEWIDE;
1500                 } else {
1501                         $styleOrigin = ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL;
1502                 }
1503                 $this->reduceAllowedModules(
1504                         ResourceLoaderModule::TYPE_STYLES,
1505                         $styleOrigin
1506                 );
1507         }
1508
1509         /**
1510          * Show what level of JavaScript / CSS untrustworthiness is allowed on this page
1511          * @see ResourceLoaderModule::$origin
1512          * @param string $type ResourceLoaderModule TYPE_ constant
1513          * @return int ResourceLoaderModule ORIGIN_ class constant
1514          */
1515         public function getAllowedModules( $type ) {
1516                 if ( $type == ResourceLoaderModule::TYPE_COMBINED ) {
1517                         return min( array_values( $this->mAllowedModules ) );
1518                 } else {
1519                         return isset( $this->mAllowedModules[$type] )
1520                                 ? $this->mAllowedModules[$type]
1521                                 : ResourceLoaderModule::ORIGIN_ALL;
1522                 }
1523         }
1524
1525         /**
1526          * Limit the highest level of CSS/JS untrustworthiness allowed.
1527          *
1528          * If passed the same or a higher level than the current level of untrustworthiness set, the
1529          * level will remain unchanged.
1530          *
1531          * @param string $type
1532          * @param int $level ResourceLoaderModule class constant
1533          */
1534         public function reduceAllowedModules( $type, $level ) {
1535                 $this->mAllowedModules[$type] = min( $this->getAllowedModules( $type ), $level );
1536         }
1537
1538         /**
1539          * Prepend $text to the body HTML
1540          *
1541          * @param string $text HTML
1542          */
1543         public function prependHTML( $text ) {
1544                 $this->mBodytext = $text . $this->mBodytext;
1545         }
1546
1547         /**
1548          * Append $text to the body HTML
1549          *
1550          * @param string $text HTML
1551          */
1552         public function addHTML( $text ) {
1553                 $this->mBodytext .= $text;
1554         }
1555
1556         /**
1557          * Shortcut for adding an Html::element via addHTML.
1558          *
1559          * @since 1.19
1560          *
1561          * @param string $element
1562          * @param array $attribs
1563          * @param string $contents
1564          */
1565         public function addElement( $element, array $attribs = [], $contents = '' ) {
1566                 $this->addHTML( Html::element( $element, $attribs, $contents ) );
1567         }
1568
1569         /**
1570          * Clear the body HTML
1571          */
1572         public function clearHTML() {
1573                 $this->mBodytext = '';
1574         }
1575
1576         /**
1577          * Get the body HTML
1578          *
1579          * @return string HTML
1580          */
1581         public function getHTML() {
1582                 return $this->mBodytext;
1583         }
1584
1585         /**
1586          * Get/set the ParserOptions object to use for wikitext parsing
1587          *
1588          * @param ParserOptions|null $options Either the ParserOption to use or null to only get the
1589          *   current ParserOption object. This parameter is deprecated since 1.31.
1590          * @return ParserOptions
1591          */
1592         public function parserOptions( $options = null ) {
1593                 if ( $options !== null ) {
1594                         wfDeprecated( __METHOD__ . ' with non-null $options', '1.31' );
1595                 }
1596
1597                 if ( $options !== null && !empty( $options->isBogus ) ) {
1598                         // Someone is trying to set a bogus pre-$wgUser PO. Check if it has
1599                         // been changed somehow, and keep it if so.
1600                         $anonPO = ParserOptions::newFromAnon();
1601                         $anonPO->setAllowUnsafeRawHtml( false );
1602                         if ( !$options->matches( $anonPO ) ) {
1603                                 wfLogWarning( __METHOD__ . ': Setting a changed bogus ParserOptions: ' . wfGetAllCallers( 5 ) );
1604                                 $options->isBogus = false;
1605                         }
1606                 }
1607
1608                 if ( !$this->mParserOptions ) {
1609                         if ( !$this->getContext()->getUser()->isSafeToLoad() ) {
1610                                 // $wgUser isn't unstubbable yet, so don't try to get a
1611                                 // ParserOptions for it. And don't cache this ParserOptions
1612                                 // either.
1613                                 $po = ParserOptions::newFromAnon();
1614                                 $po->setAllowUnsafeRawHtml( false );
1615                                 $po->isBogus = true;
1616                                 if ( $options !== null ) {
1617                                         $this->mParserOptions = empty( $options->isBogus ) ? $options : null;
1618                                 }
1619                                 return $po;
1620                         }
1621
1622                         $this->mParserOptions = ParserOptions::newFromContext( $this->getContext() );
1623                         $this->mParserOptions->setAllowUnsafeRawHtml( false );
1624                 }
1625
1626                 if ( $options !== null && !empty( $options->isBogus ) ) {
1627                         // They're trying to restore the bogus pre-$wgUser PO. Do the right
1628                         // thing.
1629                         return wfSetVar( $this->mParserOptions, null, true );
1630                 } else {
1631                         return wfSetVar( $this->mParserOptions, $options );
1632                 }
1633         }
1634
1635         /**
1636          * Set the revision ID which will be seen by the wiki text parser
1637          * for things such as embedded {{REVISIONID}} variable use.
1638          *
1639          * @param int|null $revid An positive integer, or null
1640          * @return mixed Previous value
1641          */
1642         public function setRevisionId( $revid ) {
1643                 $val = is_null( $revid ) ? null : intval( $revid );
1644                 return wfSetVar( $this->mRevisionId, $val );
1645         }
1646
1647         /**
1648          * Get the displayed revision ID
1649          *
1650          * @return int
1651          */
1652         public function getRevisionId() {
1653                 return $this->mRevisionId;
1654         }
1655
1656         /**
1657          * Set the timestamp of the revision which will be displayed. This is used
1658          * to avoid a extra DB call in Skin::lastModified().
1659          *
1660          * @param string|null $timestamp
1661          * @return mixed Previous value
1662          */
1663         public function setRevisionTimestamp( $timestamp ) {
1664                 return wfSetVar( $this->mRevisionTimestamp, $timestamp );
1665         }
1666
1667         /**
1668          * Get the timestamp of displayed revision.
1669          * This will be null if not filled by setRevisionTimestamp().
1670          *
1671          * @return string|null
1672          */
1673         public function getRevisionTimestamp() {
1674                 return $this->mRevisionTimestamp;
1675         }
1676
1677         /**
1678          * Set the displayed file version
1679          *
1680          * @param File|bool $file
1681          * @return mixed Previous value
1682          */
1683         public function setFileVersion( $file ) {
1684                 $val = null;
1685                 if ( $file instanceof File && $file->exists() ) {
1686                         $val = [ 'time' => $file->getTimestamp(), 'sha1' => $file->getSha1() ];
1687                 }
1688                 return wfSetVar( $this->mFileVersion, $val, true );
1689         }
1690
1691         /**
1692          * Get the displayed file version
1693          *
1694          * @return array|null ('time' => MW timestamp, 'sha1' => sha1)
1695          */
1696         public function getFileVersion() {
1697                 return $this->mFileVersion;
1698         }
1699
1700         /**
1701          * Get the templates used on this page
1702          *
1703          * @return array (namespace => dbKey => revId)
1704          * @since 1.18
1705          */
1706         public function getTemplateIds() {
1707                 return $this->mTemplateIds;
1708         }
1709
1710         /**
1711          * Get the files used on this page
1712          *
1713          * @return array (dbKey => array('time' => MW timestamp or null, 'sha1' => sha1 or ''))
1714          * @since 1.18
1715          */
1716         public function getFileSearchOptions() {
1717                 return $this->mImageTimeKeys;
1718         }
1719
1720         /**
1721          * Convert wikitext to HTML and add it to the buffer
1722          * Default assumes that the current page title will be used.
1723          *
1724          * @param string $text
1725          * @param bool $linestart Is this the start of a line?
1726          * @param bool $interface Is this text in the user interface language?
1727          * @throws MWException
1728          */
1729         public function addWikiText( $text, $linestart = true, $interface = true ) {
1730                 $title = $this->getTitle(); // Work around E_STRICT
1731                 if ( !$title ) {
1732                         throw new MWException( 'Title is null' );
1733                 }
1734                 $this->addWikiTextTitle( $text, $title, $linestart, /*tidy*/false, $interface );
1735         }
1736
1737         /**
1738          * Add wikitext with a custom Title object
1739          *
1740          * @param string $text Wikitext
1741          * @param Title &$title
1742          * @param bool $linestart Is this the start of a line?
1743          */
1744         public function addWikiTextWithTitle( $text, &$title, $linestart = true ) {
1745                 $this->addWikiTextTitle( $text, $title, $linestart );
1746         }
1747
1748         /**
1749          * Add wikitext with a custom Title object and tidy enabled.
1750          *
1751          * @param string $text Wikitext
1752          * @param Title &$title
1753          * @param bool $linestart Is this the start of a line?
1754          */
1755         function addWikiTextTitleTidy( $text, &$title, $linestart = true ) {
1756                 $this->addWikiTextTitle( $text, $title, $linestart, true );
1757         }
1758
1759         /**
1760          * Add wikitext with tidy enabled
1761          *
1762          * @param string $text Wikitext
1763          * @param bool $linestart Is this the start of a line?
1764          */
1765         public function addWikiTextTidy( $text, $linestart = true ) {
1766                 $title = $this->getTitle();
1767                 $this->addWikiTextTitleTidy( $text, $title, $linestart );
1768         }
1769
1770         /**
1771          * Add wikitext with a custom Title object
1772          *
1773          * @param string $text Wikitext
1774          * @param Title $title
1775          * @param bool $linestart Is this the start of a line?
1776          * @param bool $tidy Whether to use tidy
1777          * @param bool $interface Whether it is an interface message
1778          *   (for example disables conversion)
1779          */
1780         public function addWikiTextTitle( $text, Title $title, $linestart,
1781                 $tidy = false, $interface = false
1782         ) {
1783                 global $wgParser;
1784
1785                 $popts = $this->parserOptions();
1786                 $oldTidy = $popts->setTidy( $tidy );
1787                 $popts->setInterfaceMessage( (bool)$interface );
1788
1789                 $parserOutput = $wgParser->getFreshParser()->parse(
1790                         $text, $title, $popts,
1791                         $linestart, true, $this->mRevisionId
1792                 );
1793
1794                 $popts->setTidy( $oldTidy );
1795
1796                 $this->addParserOutput( $parserOutput, [
1797                         'enableSectionEditLinks' => false,
1798                 ] );
1799         }
1800
1801         /**
1802          * Add all metadata associated with a ParserOutput object, but without the actual HTML. This
1803          * includes categories, language links, ResourceLoader modules, effects of certain magic words,
1804          * and so on.
1805          *
1806          * @since 1.24
1807          * @param ParserOutput $parserOutput
1808          */
1809         public function addParserOutputMetadata( $parserOutput ) {
1810                 $this->mLanguageLinks += $parserOutput->getLanguageLinks();
1811                 $this->addCategoryLinks( $parserOutput->getCategories() );
1812                 $this->setIndicators( $parserOutput->getIndicators() );
1813                 $this->mNewSectionLink = $parserOutput->getNewSection();
1814                 $this->mHideNewSectionLink = $parserOutput->getHideNewSection();
1815
1816                 if ( !$parserOutput->isCacheable() ) {
1817                         $this->enableClientCache( false );
1818                 }
1819                 $this->mNoGallery = $parserOutput->getNoGallery();
1820                 $this->mHeadItems = array_merge( $this->mHeadItems, $parserOutput->getHeadItems() );
1821                 $this->addModules( $parserOutput->getModules() );
1822                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1823                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1824                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1825                 $this->mPreventClickjacking = $this->mPreventClickjacking
1826                         || $parserOutput->preventClickjacking();
1827
1828                 // Template versioning...
1829                 foreach ( (array)$parserOutput->getTemplateIds() as $ns => $dbks ) {
1830                         if ( isset( $this->mTemplateIds[$ns] ) ) {
1831                                 $this->mTemplateIds[$ns] = $dbks + $this->mTemplateIds[$ns];
1832                         } else {
1833                                 $this->mTemplateIds[$ns] = $dbks;
1834                         }
1835                 }
1836                 // File versioning...
1837                 foreach ( (array)$parserOutput->getFileSearchOptions() as $dbk => $data ) {
1838                         $this->mImageTimeKeys[$dbk] = $data;
1839                 }
1840
1841                 // Hooks registered in the object
1842                 $parserOutputHooks = $this->getConfig()->get( 'ParserOutputHooks' );
1843                 foreach ( $parserOutput->getOutputHooks() as $hookInfo ) {
1844                         list( $hookName, $data ) = $hookInfo;
1845                         if ( isset( $parserOutputHooks[$hookName] ) ) {
1846                                 call_user_func( $parserOutputHooks[$hookName], $this, $parserOutput, $data );
1847                         }
1848                 }
1849
1850                 // Enable OOUI if requested via ParserOutput
1851                 if ( $parserOutput->getEnableOOUI() ) {
1852                         $this->enableOOUI();
1853                 }
1854
1855                 // Include parser limit report
1856                 if ( !$this->limitReportJSData ) {
1857                         $this->limitReportJSData = $parserOutput->getLimitReportJSData();
1858                 }
1859
1860                 // Link flags are ignored for now, but may in the future be
1861                 // used to mark individual language links.
1862                 $linkFlags = [];
1863                 // Avoid PHP 7.1 warning of passing $this by reference
1864                 $outputPage = $this;
1865                 Hooks::run( 'LanguageLinks', [ $this->getTitle(), &$this->mLanguageLinks, &$linkFlags ] );
1866                 Hooks::runWithoutAbort( 'OutputPageParserOutput', [ &$outputPage, $parserOutput ] );
1867
1868                 // This check must be after 'OutputPageParserOutput' runs in addParserOutputMetadata
1869                 // so that extensions may modify ParserOutput to toggle TOC.
1870                 // This cannot be moved to addParserOutputText because that is not
1871                 // called by EditPage for Preview.
1872                 if ( $parserOutput->getTOCHTML() ) {
1873                         $this->mEnableTOC = true;
1874                 }
1875         }
1876
1877         /**
1878          * Add the HTML and enhancements for it (like ResourceLoader modules) associated with a
1879          * ParserOutput object, without any other metadata.
1880          *
1881          * @since 1.24
1882          * @param ParserOutput $parserOutput
1883          * @param array $poOptions Options to ParserOutput::getText()
1884          */
1885         public function addParserOutputContent( $parserOutput, $poOptions = [] ) {
1886                 $this->addParserOutputText( $parserOutput, $poOptions );
1887
1888                 $this->addModules( $parserOutput->getModules() );
1889                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1890                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1891
1892                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1893         }
1894
1895         /**
1896          * Add the HTML associated with a ParserOutput object, without any metadata.
1897          *
1898          * @since 1.24
1899          * @param ParserOutput $parserOutput
1900          * @param array $poOptions Options to ParserOutput::getText()
1901          */
1902         public function addParserOutputText( $parserOutput, $poOptions = [] ) {
1903                 $text = $parserOutput->getText( $poOptions );
1904                 // Avoid PHP 7.1 warning of passing $this by reference
1905                 $outputPage = $this;
1906                 Hooks::runWithoutAbort( 'OutputPageBeforeHTML', [ &$outputPage, &$text ] );
1907                 $this->addHTML( $text );
1908         }
1909
1910         /**
1911          * Add everything from a ParserOutput object.
1912          *
1913          * @param ParserOutput $parserOutput
1914          * @param array $poOptions Options to ParserOutput::getText()
1915          */
1916         function addParserOutput( $parserOutput, $poOptions = [] ) {
1917                 $this->addParserOutputMetadata( $parserOutput );
1918                 $this->addParserOutputText( $parserOutput, $poOptions );
1919         }
1920
1921         /**
1922          * Add the output of a QuickTemplate to the output buffer
1923          *
1924          * @param QuickTemplate &$template
1925          */
1926         public function addTemplate( &$template ) {
1927                 $this->addHTML( $template->getHTML() );
1928         }
1929
1930         /**
1931          * Parse wikitext and return the HTML.
1932          *
1933          * @param string $text
1934          * @param bool $linestart Is this the start of a line?
1935          * @param bool $interface Use interface language ($wgLang instead of
1936          *   $wgContLang) while parsing language sensitive magic words like GRAMMAR and PLURAL.
1937          *   This also disables LanguageConverter.
1938          * @param Language $language Target language object, will override $interface
1939          * @throws MWException
1940          * @return string HTML
1941          */
1942         public function parse( $text, $linestart = true, $interface = false, $language = null ) {
1943                 global $wgParser;
1944
1945                 if ( is_null( $this->getTitle() ) ) {
1946                         throw new MWException( 'Empty $mTitle in ' . __METHOD__ );
1947                 }
1948
1949                 $popts = $this->parserOptions();
1950                 if ( $interface ) {
1951                         $popts->setInterfaceMessage( true );
1952                 }
1953                 if ( $language !== null ) {
1954                         $oldLang = $popts->setTargetLanguage( $language );
1955                 }
1956
1957                 $parserOutput = $wgParser->getFreshParser()->parse(
1958                         $text, $this->getTitle(), $popts,
1959                         $linestart, true, $this->mRevisionId
1960                 );
1961
1962                 if ( $interface ) {
1963                         $popts->setInterfaceMessage( false );
1964                 }
1965                 if ( $language !== null ) {
1966                         $popts->setTargetLanguage( $oldLang );
1967                 }
1968
1969                 return $parserOutput->getText( [
1970                         'enableSectionEditLinks' => false,
1971                 ] );
1972         }
1973
1974         /**
1975          * Parse wikitext, strip paragraphs, and return the HTML.
1976          *
1977          * @param string $text
1978          * @param bool $linestart Is this the start of a line?
1979          * @param bool $interface Use interface language ($wgLang instead of
1980          *   $wgContLang) while parsing language sensitive magic
1981          *   words like GRAMMAR and PLURAL
1982          * @return string HTML
1983          */
1984         public function parseInline( $text, $linestart = true, $interface = false ) {
1985                 $parsed = $this->parse( $text, $linestart, $interface );
1986                 return Parser::stripOuterParagraph( $parsed );
1987         }
1988
1989         /**
1990          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header
1991          *
1992          * @param int $maxage Maximum cache time on the CDN, in seconds.
1993          */
1994         public function setCdnMaxage( $maxage ) {
1995                 $this->mCdnMaxage = min( $maxage, $this->mCdnMaxageLimit );
1996         }
1997
1998         /**
1999          * Lower the value of the "s-maxage" part of the "Cache-control" HTTP header
2000          *
2001          * @param int $maxage Maximum cache time on the CDN, in seconds
2002          * @since 1.27
2003          */
2004         public function lowerCdnMaxage( $maxage ) {
2005                 $this->mCdnMaxageLimit = min( $maxage, $this->mCdnMaxageLimit );
2006                 $this->setCdnMaxage( $this->mCdnMaxage );
2007         }
2008
2009         /**
2010          * Get TTL in [$minTTL,$maxTTL] in pass it to lowerCdnMaxage()
2011          *
2012          * This sets and returns $minTTL if $mtime is false or null. Otherwise,
2013          * the TTL is higher the older the $mtime timestamp is. Essentially, the
2014          * TTL is 90% of the age of the object, subject to the min and max.
2015          *
2016          * @param string|int|float|bool|null $mtime Last-Modified timestamp
2017          * @param int $minTTL Mimimum TTL in seconds [default: 1 minute]
2018          * @param int $maxTTL Maximum TTL in seconds [default: $wgSquidMaxage]
2019          * @return int TTL in seconds
2020          * @since 1.28
2021          */
2022         public function adaptCdnTTL( $mtime, $minTTL = 0, $maxTTL = 0 ) {
2023                 $minTTL = $minTTL ?: IExpiringStore::TTL_MINUTE;
2024                 $maxTTL = $maxTTL ?: $this->getConfig()->get( 'SquidMaxage' );
2025
2026                 if ( $mtime === null || $mtime === false ) {
2027                         return $minTTL; // entity does not exist
2028                 }
2029
2030                 $age = time() - wfTimestamp( TS_UNIX, $mtime );
2031                 $adaptiveTTL = max( 0.9 * $age, $minTTL );
2032                 $adaptiveTTL = min( $adaptiveTTL, $maxTTL );
2033
2034                 $this->lowerCdnMaxage( (int)$adaptiveTTL );
2035
2036                 return $adaptiveTTL;
2037         }
2038
2039         /**
2040          * Use enableClientCache(false) to force it to send nocache headers
2041          *
2042          * @param bool $state
2043          *
2044          * @return bool
2045          */
2046         public function enableClientCache( $state ) {
2047                 return wfSetVar( $this->mEnableClientCache, $state );
2048         }
2049
2050         /**
2051          * Get the list of cookies that will influence on the cache
2052          *
2053          * @return array
2054          */
2055         function getCacheVaryCookies() {
2056                 static $cookies;
2057                 if ( $cookies === null ) {
2058                         $config = $this->getConfig();
2059                         $cookies = array_merge(
2060                                 SessionManager::singleton()->getVaryCookies(),
2061                                 [
2062                                         'forceHTTPS',
2063                                 ],
2064                                 $config->get( 'CacheVaryCookies' )
2065                         );
2066                         Hooks::run( 'GetCacheVaryCookies', [ $this, &$cookies ] );
2067                 }
2068                 return $cookies;
2069         }
2070
2071         /**
2072          * Check if the request has a cache-varying cookie header
2073          * If it does, it's very important that we don't allow public caching
2074          *
2075          * @return bool
2076          */
2077         function haveCacheVaryCookies() {
2078                 $request = $this->getRequest();
2079                 foreach ( $this->getCacheVaryCookies() as $cookieName ) {
2080                         if ( $request->getCookie( $cookieName, '', '' ) !== '' ) {
2081                                 wfDebug( __METHOD__ . ": found $cookieName\n" );
2082                                 return true;
2083                         }
2084                 }
2085                 wfDebug( __METHOD__ . ": no cache-varying cookies found\n" );
2086                 return false;
2087         }
2088
2089         /**
2090          * Add an HTTP header that will influence on the cache
2091          *
2092          * @param string $header Header name
2093          * @param string[]|null $option Options for the Key header. See
2094          * https://datatracker.ietf.org/doc/draft-fielding-http-key/
2095          * for the list of valid options.
2096          */
2097         public function addVaryHeader( $header, array $option = null ) {
2098                 if ( !array_key_exists( $header, $this->mVaryHeader ) ) {
2099                         $this->mVaryHeader[$header] = [];
2100                 }
2101                 if ( !is_array( $option ) ) {
2102                         $option = [];
2103                 }
2104                 $this->mVaryHeader[$header] = array_unique( array_merge( $this->mVaryHeader[$header], $option ) );
2105         }
2106
2107         /**
2108          * Return a Vary: header on which to vary caches. Based on the keys of $mVaryHeader,
2109          * such as Accept-Encoding or Cookie
2110          *
2111          * @return string
2112          */
2113         public function getVaryHeader() {
2114                 // If we vary on cookies, let's make sure it's always included here too.
2115                 if ( $this->getCacheVaryCookies() ) {
2116                         $this->addVaryHeader( 'Cookie' );
2117                 }
2118
2119                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2120                         $this->addVaryHeader( $header, $options );
2121                 }
2122                 return 'Vary: ' . implode( ', ', array_keys( $this->mVaryHeader ) );
2123         }
2124
2125         /**
2126          * Add an HTTP Link: header
2127          *
2128          * @param string $header Header value
2129          */
2130         public function addLinkHeader( $header ) {
2131                 $this->mLinkHeader[] = $header;
2132         }
2133
2134         /**
2135          * Return a Link: header. Based on the values of $mLinkHeader.
2136          *
2137          * @return string
2138          */
2139         public function getLinkHeader() {
2140                 if ( !$this->mLinkHeader ) {
2141                         return false;
2142                 }
2143
2144                 return 'Link: ' . implode( ',', $this->mLinkHeader );
2145         }
2146
2147         /**
2148          * Get a complete Key header
2149          *
2150          * @return string
2151          */
2152         public function getKeyHeader() {
2153                 $cvCookies = $this->getCacheVaryCookies();
2154
2155                 $cookiesOption = [];
2156                 foreach ( $cvCookies as $cookieName ) {
2157                         $cookiesOption[] = 'param=' . $cookieName;
2158                 }
2159                 $this->addVaryHeader( 'Cookie', $cookiesOption );
2160
2161                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2162                         $this->addVaryHeader( $header, $options );
2163                 }
2164
2165                 $headers = [];
2166                 foreach ( $this->mVaryHeader as $header => $option ) {
2167                         $newheader = $header;
2168                         if ( is_array( $option ) && count( $option ) > 0 ) {
2169                                 $newheader .= ';' . implode( ';', $option );
2170                         }
2171                         $headers[] = $newheader;
2172                 }
2173                 $key = 'Key: ' . implode( ',', $headers );
2174
2175                 return $key;
2176         }
2177
2178         /**
2179          * T23672: Add Accept-Language to Vary and Key headers
2180          * if there's no 'variant' parameter existed in GET.
2181          *
2182          * For example:
2183          *   /w/index.php?title=Main_page should always be served; but
2184          *   /w/index.php?title=Main_page&variant=zh-cn should never be served.
2185          */
2186         function addAcceptLanguage() {
2187                 $title = $this->getTitle();
2188                 if ( !$title instanceof Title ) {
2189                         return;
2190                 }
2191
2192                 $lang = $title->getPageLanguage();
2193                 if ( !$this->getRequest()->getCheck( 'variant' ) && $lang->hasVariants() ) {
2194                         $variants = $lang->getVariants();
2195                         $aloption = [];
2196                         foreach ( $variants as $variant ) {
2197                                 if ( $variant === $lang->getCode() ) {
2198                                         continue;
2199                                 } else {
2200                                         $aloption[] = 'substr=' . $variant;
2201
2202                                         // IE and some other browsers use BCP 47 standards in
2203                                         // their Accept-Language header, like "zh-CN" or "zh-Hant".
2204                                         // We should handle these too.
2205                                         $variantBCP47 = LanguageCode::bcp47( $variant );
2206                                         if ( $variantBCP47 !== $variant ) {
2207                                                 $aloption[] = 'substr=' . $variantBCP47;
2208                                         }
2209                                 }
2210                         }
2211                         $this->addVaryHeader( 'Accept-Language', $aloption );
2212                 }
2213         }
2214
2215         /**
2216          * Set a flag which will cause an X-Frame-Options header appropriate for
2217          * edit pages to be sent. The header value is controlled by
2218          * $wgEditPageFrameOptions.
2219          *
2220          * This is the default for special pages. If you display a CSRF-protected
2221          * form on an ordinary view page, then you need to call this function.
2222          *
2223          * @param bool $enable
2224          */
2225         public function preventClickjacking( $enable = true ) {
2226                 $this->mPreventClickjacking = $enable;
2227         }
2228
2229         /**
2230          * Turn off frame-breaking. Alias for $this->preventClickjacking(false).
2231          * This can be called from pages which do not contain any CSRF-protected
2232          * HTML form.
2233          */
2234         public function allowClickjacking() {
2235                 $this->mPreventClickjacking = false;
2236         }
2237
2238         /**
2239          * Get the prevent-clickjacking flag
2240          *
2241          * @since 1.24
2242          * @return bool
2243          */
2244         public function getPreventClickjacking() {
2245                 return $this->mPreventClickjacking;
2246         }
2247
2248         /**
2249          * Get the X-Frame-Options header value (without the name part), or false
2250          * if there isn't one. This is used by Skin to determine whether to enable
2251          * JavaScript frame-breaking, for clients that don't support X-Frame-Options.
2252          *
2253          * @return string|false
2254          */
2255         public function getFrameOptions() {
2256                 $config = $this->getConfig();
2257                 if ( $config->get( 'BreakFrames' ) ) {
2258                         return 'DENY';
2259                 } elseif ( $this->mPreventClickjacking && $config->get( 'EditPageFrameOptions' ) ) {
2260                         return $config->get( 'EditPageFrameOptions' );
2261                 }
2262                 return false;
2263         }
2264
2265         /**
2266          * Send cache control HTTP headers
2267          */
2268         public function sendCacheControl() {
2269                 $response = $this->getRequest()->response();
2270                 $config = $this->getConfig();
2271
2272                 $this->addVaryHeader( 'Cookie' );
2273                 $this->addAcceptLanguage();
2274
2275                 # don't serve compressed data to clients who can't handle it
2276                 # maintain different caches for logged-in users and non-logged in ones
2277                 $response->header( $this->getVaryHeader() );
2278
2279                 if ( $config->get( 'UseKeyHeader' ) ) {
2280                         $response->header( $this->getKeyHeader() );
2281                 }
2282
2283                 if ( $this->mEnableClientCache ) {
2284                         if (
2285                                 $config->get( 'UseSquid' ) &&
2286                                 !$response->hasCookies() &&
2287                                 !SessionManager::getGlobalSession()->isPersistent() &&
2288                                 !$this->isPrintable() &&
2289                                 $this->mCdnMaxage != 0 &&
2290                                 !$this->haveCacheVaryCookies()
2291                         ) {
2292                                 if ( $config->get( 'UseESI' ) ) {
2293                                         # We'll purge the proxy cache explicitly, but require end user agents
2294                                         # to revalidate against the proxy on each visit.
2295                                         # Surrogate-Control controls our CDN, Cache-Control downstream caches
2296                                         wfDebug( __METHOD__ .
2297                                                 ": proxy caching with ESI; {$this->mLastModified} **", 'private' );
2298                                         # start with a shorter timeout for initial testing
2299                                         # header( 'Surrogate-Control: max-age=2678400+2678400, content="ESI/1.0"');
2300                                         $response->header(
2301                                                 "Surrogate-Control: max-age={$config->get( 'SquidMaxage' )}" .
2302                                                 "+{$this->mCdnMaxage}, content=\"ESI/1.0\""
2303                                         );
2304                                         $response->header( 'Cache-Control: s-maxage=0, must-revalidate, max-age=0' );
2305                                 } else {
2306                                         # We'll purge the proxy cache for anons explicitly, but require end user agents
2307                                         # to revalidate against the proxy on each visit.
2308                                         # IMPORTANT! The CDN needs to replace the Cache-Control header with
2309                                         # Cache-Control: s-maxage=0, must-revalidate, max-age=0
2310                                         wfDebug( __METHOD__ .
2311                                                 ": local proxy caching; {$this->mLastModified} **", 'private' );
2312                                         # start with a shorter timeout for initial testing
2313                                         # header( "Cache-Control: s-maxage=2678400, must-revalidate, max-age=0" );
2314                                         $response->header( "Cache-Control: " .
2315                                                 "s-maxage={$this->mCdnMaxage}, must-revalidate, max-age=0" );
2316                                 }
2317                         } else {
2318                                 # We do want clients to cache if they can, but they *must* check for updates
2319                                 # on revisiting the page.
2320                                 wfDebug( __METHOD__ . ": private caching; {$this->mLastModified} **", 'private' );
2321                                 $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2322                                 $response->header( "Cache-Control: private, must-revalidate, max-age=0" );
2323                         }
2324                         if ( $this->mLastModified ) {
2325                                 $response->header( "Last-Modified: {$this->mLastModified}" );
2326                         }
2327                 } else {
2328                         wfDebug( __METHOD__ . ": no caching **", 'private' );
2329
2330                         # In general, the absence of a last modified header should be enough to prevent
2331                         # the client from using its cache. We send a few other things just to make sure.
2332                         $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2333                         $response->header( 'Cache-Control: no-cache, no-store, max-age=0, must-revalidate' );
2334                         $response->header( 'Pragma: no-cache' );
2335                 }
2336         }
2337
2338         /**
2339          * Transfer styles and JavaScript modules from skin.
2340          *
2341          * @param Skin $sk to load modules for
2342          */
2343         public function loadSkinModules( $sk ) {
2344                 foreach ( $sk->getDefaultModules() as $group => $modules ) {
2345                         if ( $group === 'styles' ) {
2346                                 foreach ( $modules as $key => $moduleMembers ) {
2347                                         $this->addModuleStyles( $moduleMembers );
2348                                 }
2349                         } else {
2350                                 $this->addModules( $modules );
2351                         }
2352                 }
2353         }
2354
2355         /**
2356          * Finally, all the text has been munged and accumulated into
2357          * the object, let's actually output it:
2358          *
2359          * @param bool $return Set to true to get the result as a string rather than sending it
2360          * @return string|null
2361          * @throws Exception
2362          * @throws FatalError
2363          * @throws MWException
2364          */
2365         public function output( $return = false ) {
2366                 global $wgContLang;
2367
2368                 if ( $this->mDoNothing ) {
2369                         return $return ? '' : null;
2370                 }
2371
2372                 $response = $this->getRequest()->response();
2373                 $config = $this->getConfig();
2374
2375                 if ( $this->mRedirect != '' ) {
2376                         # Standards require redirect URLs to be absolute
2377                         $this->mRedirect = wfExpandUrl( $this->mRedirect, PROTO_CURRENT );
2378
2379                         $redirect = $this->mRedirect;
2380                         $code = $this->mRedirectCode;
2381
2382                         if ( Hooks::run( "BeforePageRedirect", [ $this, &$redirect, &$code ] ) ) {
2383                                 if ( $code == '301' || $code == '303' ) {
2384                                         if ( !$config->get( 'DebugRedirects' ) ) {
2385                                                 $response->statusHeader( $code );
2386                                         }
2387                                         $this->mLastModified = wfTimestamp( TS_RFC2822 );
2388                                 }
2389                                 if ( $config->get( 'VaryOnXFP' ) ) {
2390                                         $this->addVaryHeader( 'X-Forwarded-Proto' );
2391                                 }
2392                                 $this->sendCacheControl();
2393
2394                                 $response->header( "Content-Type: text/html; charset=utf-8" );
2395                                 if ( $config->get( 'DebugRedirects' ) ) {
2396                                         $url = htmlspecialchars( $redirect );
2397                                         print "<!DOCTYPE html>\n<html>\n<head>\n<title>Redirect</title>\n</head>\n<body>\n";
2398                                         print "<p>Location: <a href=\"$url\">$url</a></p>\n";
2399                                         print "</body>\n</html>\n";
2400                                 } else {
2401                                         $response->header( 'Location: ' . $redirect );
2402                                 }
2403                         }
2404
2405                         return $return ? '' : null;
2406                 } elseif ( $this->mStatusCode ) {
2407                         $response->statusHeader( $this->mStatusCode );
2408                 }
2409
2410                 # Buffer output; final headers may depend on later processing
2411                 ob_start();
2412
2413                 $response->header( 'Content-type: ' . $config->get( 'MimeType' ) . '; charset=UTF-8' );
2414                 $response->header( 'Content-language: ' . $wgContLang->getHtmlCode() );
2415
2416                 // Avoid Internet Explorer "compatibility view" in IE 8-10, so that
2417                 // jQuery etc. can work correctly.
2418                 $response->header( 'X-UA-Compatible: IE=Edge' );
2419
2420                 if ( !$this->mArticleBodyOnly ) {
2421                         $sk = $this->getSkin();
2422
2423                         if ( $sk->shouldPreloadLogo() ) {
2424                                 $this->addLogoPreloadLinkHeaders();
2425                         }
2426                 }
2427
2428                 $linkHeader = $this->getLinkHeader();
2429                 if ( $linkHeader ) {
2430                         $response->header( $linkHeader );
2431                 }
2432
2433                 // Prevent framing, if requested
2434                 $frameOptions = $this->getFrameOptions();
2435                 if ( $frameOptions ) {
2436                         $response->header( "X-Frame-Options: $frameOptions" );
2437                 }
2438
2439                 ContentSecurityPolicy::sendHeaders( $this );
2440
2441                 if ( $this->mArticleBodyOnly ) {
2442                         echo $this->mBodytext;
2443                 } else {
2444                         // Enable safe mode if requested (T152169)
2445                         if ( $this->getRequest()->getBool( 'safemode' ) ) {
2446                                 $this->disallowUserJs();
2447                         }
2448
2449                         $sk = $this->getSkin();
2450                         $this->loadSkinModules( $sk );
2451
2452                         MWDebug::addModules( $this );
2453
2454                         // Avoid PHP 7.1 warning of passing $this by reference
2455                         $outputPage = $this;
2456                         // Hook that allows last minute changes to the output page, e.g.
2457                         // adding of CSS or Javascript by extensions.
2458                         Hooks::runWithoutAbort( 'BeforePageDisplay', [ &$outputPage, &$sk ] );
2459
2460                         try {
2461                                 $sk->outputPage();
2462                         } catch ( Exception $e ) {
2463                                 ob_end_clean(); // bug T129657
2464                                 throw $e;
2465                         }
2466                 }
2467
2468                 try {
2469                         // This hook allows last minute changes to final overall output by modifying output buffer
2470                         Hooks::runWithoutAbort( 'AfterFinalPageOutput', [ $this ] );
2471                 } catch ( Exception $e ) {
2472                         ob_end_clean(); // bug T129657
2473                         throw $e;
2474                 }
2475
2476                 $this->sendCacheControl();
2477
2478                 if ( $return ) {
2479                         return ob_get_clean();
2480                 } else {
2481                         ob_end_flush();
2482                         return null;
2483                 }
2484         }
2485
2486         /**
2487          * Prepare this object to display an error page; disable caching and
2488          * indexing, clear the current text and redirect, set the page's title
2489          * and optionally an custom HTML title (content of the "<title>" tag).
2490          *
2491          * @param string|Message $pageTitle Will be passed directly to setPageTitle()
2492          * @param string|Message $htmlTitle Will be passed directly to setHTMLTitle();
2493          *                   optional, if not passed the "<title>" attribute will be
2494          *                   based on $pageTitle
2495          */
2496         public function prepareErrorPage( $pageTitle, $htmlTitle = false ) {
2497                 $this->setPageTitle( $pageTitle );
2498                 if ( $htmlTitle !== false ) {
2499                         $this->setHTMLTitle( $htmlTitle );
2500                 }
2501                 $this->setRobotPolicy( 'noindex,nofollow' );
2502                 $this->setArticleRelated( false );
2503                 $this->enableClientCache( false );
2504                 $this->mRedirect = '';
2505                 $this->clearSubtitle();
2506                 $this->clearHTML();
2507         }
2508
2509         /**
2510          * Output a standard error page
2511          *
2512          * showErrorPage( 'titlemsg', 'pagetextmsg' );
2513          * showErrorPage( 'titlemsg', 'pagetextmsg', [ 'param1', 'param2' ] );
2514          * showErrorPage( 'titlemsg', $messageObject );
2515          * showErrorPage( $titleMessageObject, $messageObject );
2516          *
2517          * @param string|Message $title Message key (string) for page title, or a Message object
2518          * @param string|Message $msg Message key (string) for page text, or a Message object
2519          * @param array $params Message parameters; ignored if $msg is a Message object
2520          */
2521         public function showErrorPage( $title, $msg, $params = [] ) {
2522                 if ( !$title instanceof Message ) {
2523                         $title = $this->msg( $title );
2524                 }
2525
2526                 $this->prepareErrorPage( $title );
2527
2528                 if ( $msg instanceof Message ) {
2529                         if ( $params !== [] ) {
2530                                 trigger_error( 'Argument ignored: $params. The message parameters argument '
2531                                         . 'is discarded when the $msg argument is a Message object instead of '
2532                                         . 'a string.', E_USER_NOTICE );
2533                         }
2534                         $this->addHTML( $msg->parseAsBlock() );
2535                 } else {
2536                         $this->addWikiMsgArray( $msg, $params );
2537                 }
2538
2539                 $this->returnToMain();
2540         }
2541
2542         /**
2543          * Output a standard permission error page
2544          *
2545          * @param array $errors Error message keys or [key, param...] arrays
2546          * @param string $action Action that was denied or null if unknown
2547          */
2548         public function showPermissionsErrorPage( array $errors, $action = null ) {
2549                 foreach ( $errors as $key => $error ) {
2550                         $errors[$key] = (array)$error;
2551                 }
2552
2553                 // For some action (read, edit, create and upload), display a "login to do this action"
2554                 // error if all of the following conditions are met:
2555                 // 1. the user is not logged in
2556                 // 2. the only error is insufficient permissions (i.e. no block or something else)
2557                 // 3. the error can be avoided simply by logging in
2558                 if ( in_array( $action, [ 'read', 'edit', 'createpage', 'createtalk', 'upload' ] )
2559                         && $this->getUser()->isAnon() && count( $errors ) == 1 && isset( $errors[0][0] )
2560                         && ( $errors[0][0] == 'badaccess-groups' || $errors[0][0] == 'badaccess-group0' )
2561                         && ( User::groupHasPermission( 'user', $action )
2562                         || User::groupHasPermission( 'autoconfirmed', $action ) )
2563                 ) {
2564                         $displayReturnto = null;
2565
2566                         # Due to T34276, if a user does not have read permissions,
2567                         # $this->getTitle() will just give Special:Badtitle, which is
2568                         # not especially useful as a returnto parameter. Use the title
2569                         # from the request instead, if there was one.
2570                         $request = $this->getRequest();
2571                         $returnto = Title::newFromText( $request->getVal( 'title', '' ) );
2572                         if ( $action == 'edit' ) {
2573                                 $msg = 'whitelistedittext';
2574                                 $displayReturnto = $returnto;
2575                         } elseif ( $action == 'createpage' || $action == 'createtalk' ) {
2576                                 $msg = 'nocreatetext';
2577                         } elseif ( $action == 'upload' ) {
2578                                 $msg = 'uploadnologintext';
2579                         } else { # Read
2580                                 $msg = 'loginreqpagetext';
2581                                 $displayReturnto = Title::newMainPage();
2582                         }
2583
2584                         $query = [];
2585
2586                         if ( $returnto ) {
2587                                 $query['returnto'] = $returnto->getPrefixedText();
2588
2589                                 if ( !$request->wasPosted() ) {
2590                                         $returntoquery = $request->getValues();
2591                                         unset( $returntoquery['title'] );
2592                                         unset( $returntoquery['returnto'] );
2593                                         unset( $returntoquery['returntoquery'] );
2594                                         $query['returntoquery'] = wfArrayToCgi( $returntoquery );
2595                                 }
2596                         }
2597                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
2598                         $loginLink = $linkRenderer->makeKnownLink(
2599                                 SpecialPage::getTitleFor( 'Userlogin' ),
2600                                 $this->msg( 'loginreqlink' )->text(),
2601                                 [],
2602                                 $query
2603                         );
2604
2605                         $this->prepareErrorPage( $this->msg( 'loginreqtitle' ) );
2606                         $this->addHTML( $this->msg( $msg )->rawParams( $loginLink )->parse() );
2607
2608                         # Don't return to a page the user can't read otherwise
2609                         # we'll end up in a pointless loop
2610                         if ( $displayReturnto && $displayReturnto->userCan( 'read', $this->getUser() ) ) {
2611                                 $this->returnToMain( null, $displayReturnto );
2612                         }
2613                 } else {
2614                         $this->prepareErrorPage( $this->msg( 'permissionserrors' ) );
2615                         $this->addWikiText( $this->formatPermissionsErrorMessage( $errors, $action ) );
2616                 }
2617         }
2618
2619         /**
2620          * Display an error page indicating that a given version of MediaWiki is
2621          * required to use it
2622          *
2623          * @param mixed $version The version of MediaWiki needed to use the page
2624          */
2625         public function versionRequired( $version ) {
2626                 $this->prepareErrorPage( $this->msg( 'versionrequired', $version ) );
2627
2628                 $this->addWikiMsg( 'versionrequiredtext', $version );
2629                 $this->returnToMain();
2630         }
2631
2632         /**
2633          * Format a list of error messages
2634          *
2635          * @param array $errors Array of arrays returned by Title::getUserPermissionsErrors
2636          * @param string $action Action that was denied or null if unknown
2637          * @return string The wikitext error-messages, formatted into a list.
2638          */
2639         public function formatPermissionsErrorMessage( array $errors, $action = null ) {
2640                 if ( $action == null ) {
2641                         $text = $this->msg( 'permissionserrorstext', count( $errors ) )->plain() . "\n\n";
2642                 } else {
2643                         $action_desc = $this->msg( "action-$action" )->plain();
2644                         $text = $this->msg(
2645                                 'permissionserrorstext-withaction',
2646                                 count( $errors ),
2647                                 $action_desc
2648                         )->plain() . "\n\n";
2649                 }
2650
2651                 if ( count( $errors ) > 1 ) {
2652                         $text .= '<ul class="permissions-errors">' . "\n";
2653
2654                         foreach ( $errors as $error ) {
2655                                 $text .= '<li>';
2656                                 $text .= call_user_func_array( [ $this, 'msg' ], $error )->plain();
2657                                 $text .= "</li>\n";
2658                         }
2659                         $text .= '</ul>';
2660                 } else {
2661                         $text .= "<div class=\"permissions-errors\">\n" .
2662                                         call_user_func_array( [ $this, 'msg' ], reset( $errors ) )->plain() .
2663                                         "\n</div>";
2664                 }
2665
2666                 return $text;
2667         }
2668
2669         /**
2670          * Show a warning about replica DB lag
2671          *
2672          * If the lag is higher than $wgSlaveLagCritical seconds,
2673          * then the warning is a bit more obvious. If the lag is
2674          * lower than $wgSlaveLagWarning, then no warning is shown.
2675          *
2676          * @param int $lag Slave lag
2677          */
2678         public function showLagWarning( $lag ) {
2679                 $config = $this->getConfig();
2680                 if ( $lag >= $config->get( 'SlaveLagWarning' ) ) {
2681                         $lag = floor( $lag ); // floor to avoid nano seconds to display
2682                         $message = $lag < $config->get( 'SlaveLagCritical' )
2683                                 ? 'lag-warn-normal'
2684                                 : 'lag-warn-high';
2685                         $wrap = Html::rawElement( 'div', [ 'class' => "mw-{$message}" ], "\n$1\n" );
2686                         $this->wrapWikiMsg( "$wrap\n", [ $message, $this->getLanguage()->formatNum( $lag ) ] );
2687                 }
2688         }
2689
2690         public function showFatalError( $message ) {
2691                 $this->prepareErrorPage( $this->msg( 'internalerror' ) );
2692
2693                 $this->addHTML( $message );
2694         }
2695
2696         public function showUnexpectedValueError( $name, $val ) {
2697                 $this->showFatalError( $this->msg( 'unexpected', $name, $val )->text() );
2698         }
2699
2700         public function showFileCopyError( $old, $new ) {
2701                 $this->showFatalError( $this->msg( 'filecopyerror', $old, $new )->text() );
2702         }
2703
2704         public function showFileRenameError( $old, $new ) {
2705                 $this->showFatalError( $this->msg( 'filerenameerror', $old, $new )->text() );
2706         }
2707
2708         public function showFileDeleteError( $name ) {
2709                 $this->showFatalError( $this->msg( 'filedeleteerror', $name )->text() );
2710         }
2711
2712         public function showFileNotFoundError( $name ) {
2713                 $this->showFatalError( $this->msg( 'filenotfound', $name )->text() );
2714         }
2715
2716         /**
2717          * Add a "return to" link pointing to a specified title
2718          *
2719          * @param Title $title Title to link
2720          * @param array $query Query string parameters
2721          * @param string $text Text of the link (input is not escaped)
2722          * @param array $options Options array to pass to Linker
2723          */
2724         public function addReturnTo( $title, array $query = [], $text = null, $options = [] ) {
2725                 $linkRenderer = MediaWikiServices::getInstance()
2726                         ->getLinkRendererFactory()->createFromLegacyOptions( $options );
2727                 $link = $this->msg( 'returnto' )->rawParams(
2728                         $linkRenderer->makeLink( $title, $text, [], $query ) )->escaped();
2729                 $this->addHTML( "<p id=\"mw-returnto\">{$link}</p>\n" );
2730         }
2731
2732         /**
2733          * Add a "return to" link pointing to a specified title,
2734          * or the title indicated in the request, or else the main page
2735          *
2736          * @param mixed $unused
2737          * @param Title|string $returnto Title or String to return to
2738          * @param string $returntoquery Query string for the return to link
2739          */
2740         public function returnToMain( $unused = null, $returnto = null, $returntoquery = null ) {
2741                 if ( $returnto == null ) {
2742                         $returnto = $this->getRequest()->getText( 'returnto' );
2743                 }
2744
2745                 if ( $returntoquery == null ) {
2746                         $returntoquery = $this->getRequest()->getText( 'returntoquery' );
2747                 }
2748
2749                 if ( $returnto === '' ) {
2750                         $returnto = Title::newMainPage();
2751                 }
2752
2753                 if ( is_object( $returnto ) ) {
2754                         $titleObj = $returnto;
2755                 } else {
2756                         $titleObj = Title::newFromText( $returnto );
2757                 }
2758                 // We don't want people to return to external interwiki. That
2759                 // might potentially be used as part of a phishing scheme
2760                 if ( !is_object( $titleObj ) || $titleObj->isExternal() ) {
2761                         $titleObj = Title::newMainPage();
2762                 }
2763
2764                 $this->addReturnTo( $titleObj, wfCgiToArray( $returntoquery ) );
2765         }
2766
2767         private function getRlClientContext() {
2768                 if ( !$this->rlClientContext ) {
2769                         $query = ResourceLoader::makeLoaderQuery(
2770                                 [], // modules; not relevant
2771                                 $this->getLanguage()->getCode(),
2772                                 $this->getSkin()->getSkinName(),
2773                                 $this->getUser()->isLoggedIn() ? $this->getUser()->getName() : null,
2774                                 null, // version; not relevant
2775                                 ResourceLoader::inDebugMode(),
2776                                 null, // only; not relevant
2777                                 $this->isPrintable(),
2778                                 $this->getRequest()->getBool( 'handheld' )
2779                         );
2780                         $this->rlClientContext = new ResourceLoaderContext(
2781                                 $this->getResourceLoader(),
2782                                 new FauxRequest( $query )
2783                         );
2784                         if ( $this->contentOverrideCallbacks ) {
2785                                 $this->rlClientContext = new DerivativeResourceLoaderContext( $this->rlClientContext );
2786                                 $this->rlClientContext->setContentOverrideCallback( function ( Title $title ) {
2787                                         foreach ( $this->contentOverrideCallbacks as $callback ) {
2788                                                 $content = call_user_func( $callback, $title );
2789                                                 if ( $content !== null ) {
2790                                                         return $content;
2791                                                 }
2792                                         }
2793                                         return null;
2794                                 } );
2795                         }
2796                 }
2797                 return $this->rlClientContext;
2798         }
2799
2800         /**
2801          * Call this to freeze the module queue and JS config and create a formatter.
2802          *
2803          * Depending on the Skin, this may get lazy-initialised in either headElement() or
2804          * getBottomScripts(). See SkinTemplate::prepareQuickTemplate(). Calling this too early may
2805          * cause unexpected side-effects since disallowUserJs() may be called at any time to change
2806          * the module filters retroactively. Skins and extension hooks may also add modules until very
2807          * late in the request lifecycle.
2808          *
2809          * @return ResourceLoaderClientHtml
2810          */
2811         public function getRlClient() {
2812                 if ( !$this->rlClient ) {
2813                         $context = $this->getRlClientContext();
2814                         $rl = $this->getResourceLoader();
2815                         $this->addModules( [
2816                                 'user',
2817                                 'user.options',
2818                                 'user.tokens',
2819                         ] );
2820                         $this->addModuleStyles( [
2821                                 'site.styles',
2822                                 'noscript',
2823                                 'user.styles',
2824                         ] );
2825                         $this->getSkin()->setupSkinUserCss( $this );
2826
2827                         // Prepare exempt modules for buildExemptModules()
2828                         $exemptGroups = [ 'site' => [], 'noscript' => [], 'private' => [], 'user' => [] ];
2829                         $exemptStates = [];
2830                         $moduleStyles = $this->getModuleStyles( /*filter*/ true );
2831
2832                         // Preload getTitleInfo for isKnownEmpty calls below and in ResourceLoaderClientHtml
2833                         // Separate user-specific batch for improved cache-hit ratio.
2834                         $userBatch = [ 'user.styles', 'user' ];
2835                         $siteBatch = array_diff( $moduleStyles, $userBatch );
2836                         $dbr = wfGetDB( DB_REPLICA );
2837                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $siteBatch );
2838                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $userBatch );
2839
2840                         // Filter out modules handled by buildExemptModules()
2841                         $moduleStyles = array_filter( $moduleStyles,
2842                                 function ( $name ) use ( $rl, $context, &$exemptGroups, &$exemptStates ) {
2843                                         $module = $rl->getModule( $name );
2844                                         if ( $module ) {
2845                                                 $group = $module->getGroup();
2846                                                 if ( isset( $exemptGroups[$group] ) ) {
2847                                                         $exemptStates[$name] = 'ready';
2848                                                         if ( !$module->isKnownEmpty( $context ) ) {
2849                                                                 // E.g. Don't output empty <styles>
2850                                                                 $exemptGroups[$group][] = $name;
2851                                                         }
2852                                                         return false;
2853                                                 }
2854                                         }
2855                                         return true;
2856                                 }
2857                         );
2858                         $this->rlExemptStyleModules = $exemptGroups;
2859
2860                         $rlClient = new ResourceLoaderClientHtml( $context, [
2861                                 'target' => $this->getTarget(),
2862                                 'nonce' => $this->getCSPNonce(),
2863                                 // When 'safemode', disallowUserJs(), or reduceAllowedModules() is used
2864                                 // to only restrict modules to ORIGIN_CORE (ie. disallow ORIGIN_USER), the list of
2865                                 // modules enqueud for loading on this page is filtered to just those.
2866                                 // However, to make sure we also apply the restriction to dynamic dependencies and
2867                                 // lazy-loaded modules at run-time on the client-side, pass 'safemode' down to the
2868                                 // StartupModule so that the client-side registry will not contain any restricted
2869                                 // modules either. (T152169, T185303)
2870                                 'safemode' => ( $this->getAllowedModules( ResourceLoaderModule::TYPE_COMBINED )
2871                                         <= ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
2872                                 ) ? '1' : null,
2873                         ] );
2874                         $rlClient->setConfig( $this->getJSVars() );
2875                         $rlClient->setModules( $this->getModules( /*filter*/ true ) );
2876                         $rlClient->setModuleStyles( $moduleStyles );
2877                         $rlClient->setModuleScripts( $this->getModuleScripts( /*filter*/ true ) );
2878                         $rlClient->setExemptStates( $exemptStates );
2879                         $this->rlClient = $rlClient;
2880                 }
2881                 return $this->rlClient;
2882         }
2883
2884         /**
2885          * @param Skin $sk The given Skin
2886          * @param bool $includeStyle Unused
2887          * @return string The doctype, opening "<html>", and head element.
2888          */
2889         public function headElement( Skin $sk, $includeStyle = true ) {
2890                 global $wgContLang;
2891
2892                 $userdir = $this->getLanguage()->getDir();
2893                 $sitedir = $wgContLang->getDir();
2894
2895                 $pieces = [];
2896                 $pieces[] = Html::htmlHeader( Sanitizer::mergeAttributes(
2897                         $this->getRlClient()->getDocumentAttributes(),
2898                         $sk->getHtmlElementAttributes()
2899                 ) );
2900                 $pieces[] = Html::openElement( 'head' );
2901
2902                 if ( $this->getHTMLTitle() == '' ) {
2903                         $this->setHTMLTitle( $this->msg( 'pagetitle', $this->getPageTitle() )->inContentLanguage() );
2904                 }
2905
2906                 if ( !Html::isXmlMimeType( $this->getConfig()->get( 'MimeType' ) ) ) {
2907                         // Add <meta charset="UTF-8">
2908                         // This should be before <title> since it defines the charset used by
2909                         // text including the text inside <title>.
2910                         // The spec recommends defining XHTML5's charset using the XML declaration
2911                         // instead of meta.
2912                         // Our XML declaration is output by Html::htmlHeader.
2913                         // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-content-type
2914                         // https://html.spec.whatwg.org/multipage/semantics.html#charset
2915                         $pieces[] = Html::element( 'meta', [ 'charset' => 'UTF-8' ] );
2916                 }
2917
2918                 $pieces[] = Html::element( 'title', null, $this->getHTMLTitle() );
2919                 $pieces[] = $this->getRlClient()->getHeadHtml();
2920                 $pieces[] = $this->buildExemptModules();
2921                 $pieces = array_merge( $pieces, array_values( $this->getHeadLinksArray() ) );
2922                 $pieces = array_merge( $pieces, array_values( $this->mHeadItems ) );
2923
2924                 // Use an IE conditional comment to serve the script only to old IE
2925                 $pieces[] = '<!--[if lt IE 9]>' .
2926                         ResourceLoaderClientHtml::makeLoad(
2927                                 ResourceLoaderContext::newDummyContext(),
2928                                 [ 'html5shiv' ],
2929                                 ResourceLoaderModule::TYPE_SCRIPTS,
2930                                 [ 'sync' => true ],
2931                                 $this->getCSPNonce()
2932                         ) .
2933                         '<![endif]-->';
2934
2935                 $pieces[] = Html::closeElement( 'head' );
2936
2937                 $bodyClasses = $this->mAdditionalBodyClasses;
2938                 $bodyClasses[] = 'mediawiki';
2939
2940                 # Classes for LTR/RTL directionality support
2941                 $bodyClasses[] = $userdir;
2942                 $bodyClasses[] = "sitedir-$sitedir";
2943
2944                 $underline = $this->getUser()->getOption( 'underline' );
2945                 if ( $underline < 2 ) {
2946                         // The following classes can be used here:
2947                         // * mw-underline-always
2948                         // * mw-underline-never
2949                         $bodyClasses[] = 'mw-underline-' . ( $underline ? 'always' : 'never' );
2950                 }
2951
2952                 if ( $this->getLanguage()->capitalizeAllNouns() ) {
2953                         # A <body> class is probably not the best way to do this . . .
2954                         $bodyClasses[] = 'capitalize-all-nouns';
2955                 }
2956
2957                 // Parser feature migration class
2958                 // The idea is that this will eventually be removed, after the wikitext
2959                 // which requires it is cleaned up.
2960                 $bodyClasses[] = 'mw-hide-empty-elt';
2961
2962                 $bodyClasses[] = $sk->getPageClasses( $this->getTitle() );
2963                 $bodyClasses[] = 'skin-' . Sanitizer::escapeClass( $sk->getSkinName() );
2964                 $bodyClasses[] =
2965                         'action-' . Sanitizer::escapeClass( Action::getActionName( $this->getContext() ) );
2966
2967                 $bodyAttrs = [];
2968                 // While the implode() is not strictly needed, it's used for backwards compatibility
2969                 // (this used to be built as a string and hooks likely still expect that).
2970                 $bodyAttrs['class'] = implode( ' ', $bodyClasses );
2971
2972                 // Allow skins and extensions to add body attributes they need
2973                 $sk->addToBodyAttributes( $this, $bodyAttrs );
2974                 Hooks::run( 'OutputPageBodyAttributes', [ $this, $sk, &$bodyAttrs ] );
2975
2976                 $pieces[] = Html::openElement( 'body', $bodyAttrs );
2977
2978                 return self::combineWrappedStrings( $pieces );
2979         }
2980
2981         /**
2982          * Get a ResourceLoader object associated with this OutputPage
2983          *
2984          * @return ResourceLoader
2985          */
2986         public function getResourceLoader() {
2987                 if ( is_null( $this->mResourceLoader ) ) {
2988                         $this->mResourceLoader = new ResourceLoader(
2989                                 $this->getConfig(),
2990                                 LoggerFactory::getInstance( 'resourceloader' )
2991                         );
2992                 }
2993                 return $this->mResourceLoader;
2994         }
2995
2996         /**
2997          * Explicily load or embed modules on a page.
2998          *
2999          * @param array|string $modules One or more module names
3000          * @param string $only ResourceLoaderModule TYPE_ class constant
3001          * @param array $extraQuery [optional] Array with extra query parameters for the request
3002          * @return string|WrappedStringList HTML
3003          */
3004         public function makeResourceLoaderLink( $modules, $only, array $extraQuery = [] ) {
3005                 // Apply 'target' and 'origin' filters
3006                 $modules = $this->filterModules( (array)$modules, null, $only );
3007
3008                 return ResourceLoaderClientHtml::makeLoad(
3009                         $this->getRlClientContext(),
3010                         $modules,
3011                         $only,
3012                         $extraQuery,
3013                         $this->getCSPNonce()
3014                 );
3015         }
3016
3017         /**
3018          * Combine WrappedString chunks and filter out empty ones
3019          *
3020          * @param array $chunks
3021          * @return string|WrappedStringList HTML
3022          */
3023         protected static function combineWrappedStrings( array $chunks ) {
3024                 // Filter out empty values
3025                 $chunks = array_filter( $chunks, 'strlen' );
3026                 return WrappedString::join( "\n", $chunks );
3027         }
3028
3029         /**
3030          * JS stuff to put at the bottom of the `<body>`.
3031          * These are legacy scripts ($this->mScripts), and user JS.
3032          *
3033          * @return string|WrappedStringList HTML
3034          */
3035         public function getBottomScripts() {
3036                 $chunks = [];
3037                 $chunks[] = $this->getRlClient()->getBodyHtml();
3038
3039                 // Legacy non-ResourceLoader scripts
3040                 $chunks[] = $this->mScripts;
3041
3042                 if ( $this->limitReportJSData ) {
3043                         $chunks[] = ResourceLoader::makeInlineScript(
3044                                 ResourceLoader::makeConfigSetScript(
3045                                         [ 'wgPageParseReport' => $this->limitReportJSData ]
3046                                 ),
3047                                 $this->getCSPNonce()
3048                         );
3049                 }
3050
3051                 return self::combineWrappedStrings( $chunks );
3052         }
3053
3054         /**
3055          * Get the javascript config vars to include on this page
3056          *
3057          * @return array Array of javascript config vars
3058          * @since 1.23
3059          */
3060         public function getJsConfigVars() {
3061                 return $this->mJsConfigVars;
3062         }
3063
3064         /**
3065          * Add one or more variables to be set in mw.config in JavaScript
3066          *
3067          * @param string|array $keys Key or array of key/value pairs
3068          * @param mixed $value [optional] Value of the configuration variable
3069          */
3070         public function addJsConfigVars( $keys, $value = null ) {
3071                 if ( is_array( $keys ) ) {
3072                         foreach ( $keys as $key => $value ) {
3073                                 $this->mJsConfigVars[$key] = $value;
3074                         }
3075                         return;
3076                 }
3077
3078                 $this->mJsConfigVars[$keys] = $value;
3079         }
3080
3081         /**
3082          * Get an array containing the variables to be set in mw.config in JavaScript.
3083          *
3084          * Do not add things here which can be evaluated in ResourceLoaderStartUpModule
3085          * - in other words, page-independent/site-wide variables (without state).
3086          * You will only be adding bloat to the html page and causing page caches to
3087          * have to be purged on configuration changes.
3088          * @return array
3089          */
3090         public function getJSVars() {
3091                 global $wgContLang;
3092
3093                 $curRevisionId = 0;
3094                 $articleId = 0;
3095                 $canonicalSpecialPageName = false; # T23115
3096
3097                 $title = $this->getTitle();
3098                 $ns = $title->getNamespace();
3099                 $canonicalNamespace = MWNamespace::exists( $ns )
3100                         ? MWNamespace::getCanonicalName( $ns )
3101                         : $title->getNsText();
3102
3103                 $sk = $this->getSkin();
3104                 // Get the relevant title so that AJAX features can use the correct page name
3105                 // when making API requests from certain special pages (T36972).
3106                 $relevantTitle = $sk->getRelevantTitle();
3107                 $relevantUser = $sk->getRelevantUser();
3108
3109                 if ( $ns == NS_SPECIAL ) {
3110                         list( $canonicalSpecialPageName, /*...*/ ) =
3111                                 SpecialPageFactory::resolveAlias( $title->getDBkey() );
3112                 } elseif ( $this->canUseWikiPage() ) {
3113                         $wikiPage = $this->getWikiPage();
3114                         $curRevisionId = $wikiPage->getLatest();
3115                         $articleId = $wikiPage->getId();
3116                 }
3117
3118                 $lang = $title->getPageViewLanguage();
3119
3120                 // Pre-process information
3121                 $separatorTransTable = $lang->separatorTransformTable();
3122                 $separatorTransTable = $separatorTransTable ? $separatorTransTable : [];
3123                 $compactSeparatorTransTable = [
3124                         implode( "\t", array_keys( $separatorTransTable ) ),
3125                         implode( "\t", $separatorTransTable ),
3126                 ];
3127                 $digitTransTable = $lang->digitTransformTable();
3128                 $digitTransTable = $digitTransTable ? $digitTransTable : [];
3129                 $compactDigitTransTable = [
3130                         implode( "\t", array_keys( $digitTransTable ) ),
3131                         implode( "\t", $digitTransTable ),
3132                 ];
3133
3134                 $user = $this->getUser();
3135
3136                 $vars = [
3137                         'wgCanonicalNamespace' => $canonicalNamespace,
3138                         'wgCanonicalSpecialPageName' => $canonicalSpecialPageName,
3139                         'wgNamespaceNumber' => $title->getNamespace(),
3140                         'wgPageName' => $title->getPrefixedDBkey(),
3141                         'wgTitle' => $title->getText(),
3142                         'wgCurRevisionId' => $curRevisionId,
3143                         'wgRevisionId' => (int)$this->getRevisionId(),
3144                         'wgArticleId' => $articleId,
3145                         'wgIsArticle' => $this->isArticle(),
3146                         'wgIsRedirect' => $title->isRedirect(),
3147                         'wgAction' => Action::getActionName( $this->getContext() ),
3148                         'wgUserName' => $user->isAnon() ? null : $user->getName(),
3149                         'wgUserGroups' => $user->getEffectiveGroups(),
3150                         'wgCategories' => $this->getCategories(),
3151                         'wgBreakFrames' => $this->getFrameOptions() == 'DENY',
3152                         'wgPageContentLanguage' => $lang->getCode(),
3153                         'wgPageContentModel' => $title->getContentModel(),
3154                         'wgSeparatorTransformTable' => $compactSeparatorTransTable,
3155                         'wgDigitTransformTable' => $compactDigitTransTable,
3156                         'wgDefaultDateFormat' => $lang->getDefaultDateFormat(),
3157                         'wgMonthNames' => $lang->getMonthNamesArray(),
3158                         'wgMonthNamesShort' => $lang->getMonthAbbreviationsArray(),
3159                         'wgRelevantPageName' => $relevantTitle->getPrefixedDBkey(),
3160                         'wgRelevantArticleId' => $relevantTitle->getArticleID(),
3161                         'wgRequestId' => WebRequest::getRequestId(),
3162                 ];
3163
3164                 if ( $user->isLoggedIn() ) {
3165                         $vars['wgUserId'] = $user->getId();
3166                         $vars['wgUserEditCount'] = $user->getEditCount();
3167                         $userReg = $user->getRegistration();
3168                         $vars['wgUserRegistration'] = $userReg ? wfTimestamp( TS_UNIX, $userReg ) * 1000 : null;
3169                         // Get the revision ID of the oldest new message on the user's talk
3170                         // page. This can be used for constructing new message alerts on
3171                         // the client side.
3172                         $vars['wgUserNewMsgRevisionId'] = $user->getNewMessageRevisionId();
3173                 }
3174
3175                 if ( $wgContLang->hasVariants() ) {
3176                         $vars['wgUserVariant'] = $wgContLang->getPreferredVariant();
3177                 }
3178                 // Same test as SkinTemplate
3179                 $vars['wgIsProbablyEditable'] = $title->quickUserCan( 'edit', $user )
3180                         && ( $title->exists() || $title->quickUserCan( 'create', $user ) );
3181
3182                 $vars['wgRelevantPageIsProbablyEditable'] = $relevantTitle
3183                         && $relevantTitle->quickUserCan( 'edit', $user )
3184                         && ( $relevantTitle->exists() || $relevantTitle->quickUserCan( 'create', $user ) );
3185
3186                 foreach ( $title->getRestrictionTypes() as $type ) {
3187                         // Following keys are set in $vars:
3188                         // wgRestrictionCreate, wgRestrictionEdit, wgRestrictionMove, wgRestrictionUpload
3189                         $vars['wgRestriction' . ucfirst( $type )] = $title->getRestrictions( $type );
3190                 }
3191
3192                 if ( $title->isMainPage() ) {
3193                         $vars['wgIsMainPage'] = true;
3194                 }
3195
3196                 if ( $this->mRedirectedFrom ) {
3197                         $vars['wgRedirectedFrom'] = $this->mRedirectedFrom->getPrefixedDBkey();
3198                 }
3199
3200                 if ( $relevantUser ) {
3201                         $vars['wgRelevantUserName'] = $relevantUser->getName();
3202                 }
3203
3204                 // Allow extensions to add their custom variables to the mw.config map.
3205                 // Use the 'ResourceLoaderGetConfigVars' hook if the variable is not
3206                 // page-dependant but site-wide (without state).
3207                 // Alternatively, you may want to use OutputPage->addJsConfigVars() instead.
3208                 Hooks::run( 'MakeGlobalVariablesScript', [ &$vars, $this ] );
3209
3210                 // Merge in variables from addJsConfigVars last
3211                 return array_merge( $vars, $this->getJsConfigVars() );
3212         }
3213
3214         /**
3215          * To make it harder for someone to slip a user a fake
3216          * JavaScript or CSS preview, a random token
3217          * is associated with the login session. If it's not
3218          * passed back with the preview request, we won't render
3219          * the code.
3220          *
3221          * @return bool
3222          */
3223         public function userCanPreview() {
3224                 $request = $this->getRequest();
3225                 if (
3226                         $request->getVal( 'action' ) !== 'submit' ||
3227                         !$request->wasPosted()
3228                 ) {
3229                         return false;
3230                 }
3231
3232                 $user = $this->getUser();
3233
3234                 if ( !$user->isLoggedIn() ) {
3235                         // Anons have predictable edit tokens
3236                         return false;
3237                 }
3238                 if ( !$user->matchEditToken( $request->getVal( 'wpEditToken' ) ) ) {
3239                         return false;
3240                 }
3241
3242                 $title = $this->getTitle();
3243                 $errors = $title->getUserPermissionsErrors( 'edit', $user );
3244                 if ( count( $errors ) !== 0 ) {
3245                         return false;
3246                 }
3247
3248                 return true;
3249         }
3250
3251         /**
3252          * @return array Array in format "link name or number => 'link html'".
3253          */
3254         public function getHeadLinksArray() {
3255                 global $wgVersion;
3256
3257                 $tags = [];
3258                 $config = $this->getConfig();
3259
3260                 $canonicalUrl = $this->mCanonicalUrl;
3261
3262                 $tags['meta-generator'] = Html::element( 'meta', [
3263                         'name' => 'generator',
3264                         'content' => "MediaWiki $wgVersion",
3265                 ] );
3266
3267                 if ( $config->get( 'ReferrerPolicy' ) !== false ) {
3268                         // Per https://w3c.github.io/webappsec-referrer-policy/#unknown-policy-values
3269                         // fallbacks should come before the primary value so we need to reverse the array.
3270                         foreach ( array_reverse( (array)$config->get( 'ReferrerPolicy' ) ) as $i => $policy ) {
3271                                 $tags["meta-referrer-$i"] = Html::element( 'meta', [
3272                                         'name' => 'referrer',
3273                                         'content' => $policy,
3274                                 ] );
3275                         }
3276                 }
3277
3278                 $p = "{$this->mIndexPolicy},{$this->mFollowPolicy}";
3279                 if ( $p !== 'index,follow' ) {
3280                         // http://www.robotstxt.org/wc/meta-user.html
3281                         // Only show if it's different from the default robots policy
3282                         $tags['meta-robots'] = Html::element( 'meta', [
3283                                 'name' => 'robots',
3284                                 'content' => $p,
3285                         ] );
3286                 }
3287
3288                 foreach ( $this->mMetatags as $tag ) {
3289                         if ( strncasecmp( $tag[0], 'http:', 5 ) === 0 ) {
3290                                 $a = 'http-equiv';
3291                                 $tag[0] = substr( $tag[0], 5 );
3292                         } elseif ( strncasecmp( $tag[0], 'og:', 3 ) === 0 ) {
3293                                 $a = 'property';
3294                         } else {
3295                                 $a = 'name';
3296                         }
3297                         $tagName = "meta-{$tag[0]}";
3298                         if ( isset( $tags[$tagName] ) ) {
3299                                 $tagName .= $tag[1];
3300                         }
3301                         $tags[$tagName] = Html::element( 'meta',
3302                                 [
3303                                         $a => $tag[0],
3304                                         'content' => $tag[1]
3305                                 ]
3306                         );
3307                 }
3308
3309                 foreach ( $this->mLinktags as $tag ) {
3310                         $tags[] = Html::element( 'link', $tag );
3311                 }
3312
3313                 # Universal edit button
3314                 if ( $config->get( 'UniversalEditButton' ) && $this->isArticleRelated() ) {
3315                         $user = $this->getUser();
3316                         if ( $this->getTitle()->quickUserCan( 'edit', $user )
3317                                 && ( $this->getTitle()->exists() ||
3318                                         $this->getTitle()->quickUserCan( 'create', $user ) )
3319                         ) {
3320                                 // Original UniversalEditButton
3321                                 $msg = $this->msg( 'edit' )->text();
3322                                 $tags['universal-edit-button'] = Html::element( 'link', [
3323                                         'rel' => 'alternate',
3324                                         'type' => 'application/x-wiki',
3325                                         'title' => $msg,
3326                                         'href' => $this->getTitle()->getEditURL(),
3327                                 ] );
3328                                 // Alternate edit link
3329                                 $tags['alternative-edit'] = Html::element( 'link', [
3330                                         'rel' => 'edit',
3331                                         'title' => $msg,
3332                                         'href' => $this->getTitle()->getEditURL(),
3333                                 ] );
3334                         }
3335                 }
3336
3337                 # Generally the order of the favicon and apple-touch-icon links
3338                 # should not matter, but Konqueror (3.5.9 at least) incorrectly
3339                 # uses whichever one appears later in the HTML source. Make sure
3340                 # apple-touch-icon is specified first to avoid this.
3341                 if ( $config->get( 'AppleTouchIcon' ) !== false ) {
3342                         $tags['apple-touch-icon'] = Html::element( 'link', [
3343                                 'rel' => 'apple-touch-icon',
3344                                 'href' => $config->get( 'AppleTouchIcon' )
3345                         ] );
3346                 }
3347
3348                 if ( $config->get( 'Favicon' ) !== false ) {
3349                         $tags['favicon'] = Html::element( 'link', [
3350                                 'rel' => 'shortcut icon',
3351                                 'href' => $config->get( 'Favicon' )
3352                         ] );
3353                 }
3354
3355                 # OpenSearch description link
3356                 $tags['opensearch'] = Html::element( 'link', [
3357                         'rel' => 'search',
3358                         'type' => 'application/opensearchdescription+xml',
3359                         'href' => wfScript( 'opensearch_desc' ),
3360                         'title' => $this->msg( 'opensearch-desc' )->inContentLanguage()->text(),
3361                 ] );
3362
3363                 # Real Simple Discovery link, provides auto-discovery information
3364                 # for the MediaWiki API (and potentially additional custom API
3365                 # support such as WordPress or Twitter-compatible APIs for a
3366                 # blogging extension, etc)
3367                 $tags['rsd'] = Html::element( 'link', [
3368                         'rel' => 'EditURI',
3369                         'type' => 'application/rsd+xml',
3370                         // Output a protocol-relative URL here if $wgServer is protocol-relative.
3371                         // Whether RSD accepts relative or protocol-relative URLs is completely
3372                         // undocumented, though.
3373                         'href' => wfExpandUrl( wfAppendQuery(
3374                                 wfScript( 'api' ),
3375                                 [ 'action' => 'rsd' ] ),
3376                                 PROTO_RELATIVE
3377                         ),
3378                 ] );
3379
3380                 # Language variants
3381                 if ( !$config->get( 'DisableLangConversion' ) ) {
3382                         $lang = $this->getTitle()->getPageLanguage();
3383                         if ( $lang->hasVariants() ) {
3384                                 $variants = $lang->getVariants();
3385                                 foreach ( $variants as $variant ) {
3386                                         $tags["variant-$variant"] = Html::element( 'link', [
3387                                                 'rel' => 'alternate',
3388                                                 'hreflang' => LanguageCode::bcp47( $variant ),
3389                                                 'href' => $this->getTitle()->getLocalURL(
3390                                                         [ 'variant' => $variant ] )
3391                                                 ]
3392                                         );
3393                                 }
3394                                 # x-default link per https://support.google.com/webmasters/answer/189077?hl=en
3395                                 $tags["variant-x-default"] = Html::element( 'link', [
3396                                         'rel' => 'alternate',
3397                                         'hreflang' => 'x-default',
3398                                         'href' => $this->getTitle()->getLocalURL() ] );
3399                         }
3400                 }
3401
3402                 # Copyright
3403                 if ( $this->copyrightUrl !== null ) {
3404                         $copyright = $this->copyrightUrl;
3405                 } else {
3406                         $copyright = '';
3407                         if ( $config->get( 'RightsPage' ) ) {
3408                                 $copy = Title::newFromText( $config->get( 'RightsPage' ) );
3409
3410                                 if ( $copy ) {
3411                                         $copyright = $copy->getLocalURL();
3412                                 }
3413                         }
3414
3415                         if ( !$copyright && $config->get( 'RightsUrl' ) ) {
3416                                 $copyright = $config->get( 'RightsUrl' );
3417                         }
3418                 }
3419
3420                 if ( $copyright ) {
3421                         $tags['copyright'] = Html::element( 'link', [
3422                                 'rel' => 'license',
3423                                 'href' => $copyright ]
3424                         );
3425                 }
3426
3427                 # Feeds
3428                 if ( $config->get( 'Feed' ) ) {
3429                         $feedLinks = [];
3430
3431                         foreach ( $this->getSyndicationLinks() as $format => $link ) {
3432                                 # Use the page name for the title.  In principle, this could
3433                                 # lead to issues with having the same name for different feeds
3434                                 # corresponding to the same page, but we can't avoid that at
3435                                 # this low a level.
3436
3437                                 $feedLinks[] = $this->feedLink(
3438                                         $format,
3439                                         $link,
3440                                         # Used messages: 'page-rss-feed' and 'page-atom-feed' (for an easier grep)
3441                                         $this->msg(
3442                                                 "page-{$format}-feed", $this->getTitle()->getPrefixedText()
3443                                         )->text()
3444                                 );
3445                         }
3446
3447                         # Recent changes feed should appear on every page (except recentchanges,
3448                         # that would be redundant). Put it after the per-page feed to avoid
3449                         # changing existing behavior. It's still available, probably via a
3450                         # menu in your browser. Some sites might have a different feed they'd
3451                         # like to promote instead of the RC feed (maybe like a "Recent New Articles"
3452                         # or "Breaking news" one). For this, we see if $wgOverrideSiteFeed is defined.
3453                         # If so, use it instead.
3454                         $sitename = $config->get( 'Sitename' );
3455                         if ( $config->get( 'OverrideSiteFeed' ) ) {
3456                                 foreach ( $config->get( 'OverrideSiteFeed' ) as $type => $feedUrl ) {
3457                                         // Note, this->feedLink escapes the url.
3458                                         $feedLinks[] = $this->feedLink(
3459                                                 $type,
3460                                                 $feedUrl,
3461                                                 $this->msg( "site-{$type}-feed", $sitename )->text()
3462                                         );
3463                                 }
3464                         } elseif ( !$this->getTitle()->isSpecial( 'Recentchanges' ) ) {
3465                                 $rctitle = SpecialPage::getTitleFor( 'Recentchanges' );
3466                                 foreach ( $config->get( 'AdvertisedFeedTypes' ) as $format ) {
3467                                         $feedLinks[] = $this->feedLink(
3468                                                 $format,
3469                                                 $rctitle->getLocalURL( [ 'feed' => $format ] ),
3470                                                 # For grep: 'site-rss-feed', 'site-atom-feed'
3471                                                 $this->msg( "site-{$format}-feed", $sitename )->text()
3472                                         );
3473                                 }
3474                         }
3475
3476                         # Allow extensions to change the list pf feeds. This hook is primarily for changing,
3477                         # manipulating or removing existing feed tags. If you want to add new feeds, you should
3478                         # use OutputPage::addFeedLink() instead.
3479                         Hooks::run( 'AfterBuildFeedLinks', [ &$feedLinks ] );
3480
3481                         $tags += $feedLinks;
3482                 }
3483
3484                 # Canonical URL
3485                 if ( $config->get( 'EnableCanonicalServerLink' ) ) {
3486                         if ( $canonicalUrl !== false ) {
3487                                 $canonicalUrl = wfExpandUrl( $canonicalUrl, PROTO_CANONICAL );
3488                         } else {
3489                                 if ( $this->isArticleRelated() ) {
3490                                         // This affects all requests where "setArticleRelated" is true. This is
3491                                         // typically all requests that show content (query title, curid, oldid, diff),
3492                                         // and all wikipage actions (edit, delete, purge, info, history etc.).
3493                                         // It does not apply to File pages and Special pages.
3494                                         // 'history' and 'info' actions address page metadata rather than the page
3495                                         // content itself, so they may not be canonicalized to the view page url.
3496                                         // TODO: this ought to be better encapsulated in the Action class.
3497                                         $action = Action::getActionName( $this->getContext() );
3498                                         if ( in_array( $action, [ 'history', 'info' ] ) ) {
3499                                                 $query = "action={$action}";
3500                                         } else {
3501                                                 $query = '';
3502                                         }
3503                                         $canonicalUrl = $this->getTitle()->getCanonicalURL( $query );
3504                                 } else {
3505                                         $reqUrl = $this->getRequest()->getRequestURL();
3506                                         $canonicalUrl = wfExpandUrl( $reqUrl, PROTO_CANONICAL );
3507                                 }
3508                         }
3509                 }
3510                 if ( $canonicalUrl !== false ) {
3511                         $tags[] = Html::element( 'link', [
3512                                 'rel' => 'canonical',
3513                                 'href' => $canonicalUrl
3514                         ] );
3515                 }
3516
3517                 return $tags;
3518         }
3519
3520         /**
3521          * Generate a "<link rel/>" for a feed.
3522          *
3523          * @param string $type Feed type
3524          * @param string $url URL to the feed
3525          * @param string $text Value of the "title" attribute
3526          * @return string HTML fragment
3527          */
3528         private function feedLink( $type, $url, $text ) {
3529                 return Html::element( 'link', [
3530                         'rel' => 'alternate',
3531                         'type' => "application/$type+xml",
3532                         'title' => $text,
3533                         'href' => $url ]
3534                 );
3535         }
3536
3537         /**
3538          * Add a local or specified stylesheet, with the given media options.
3539          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3540          *
3541          * @param string $style URL to the file
3542          * @param string $media To specify a media type, 'screen', 'printable', 'handheld' or any.
3543          * @param string $condition For IE conditional comments, specifying an IE version
3544          * @param string $dir Set to 'rtl' or 'ltr' for direction-specific sheets
3545          */
3546         public function addStyle( $style, $media = '', $condition = '', $dir = '' ) {
3547                 $options = [];
3548                 if ( $media ) {
3549                         $options['media'] = $media;
3550                 }
3551                 if ( $condition ) {
3552                         $options['condition'] = $condition;
3553                 }
3554                 if ( $dir ) {
3555                         $options['dir'] = $dir;
3556                 }
3557                 $this->styles[$style] = $options;
3558         }
3559
3560         /**
3561          * Adds inline CSS styles
3562          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3563          *
3564          * @param mixed $style_css Inline CSS
3565          * @param string $flip Set to 'flip' to flip the CSS if needed
3566          */
3567         public function addInlineStyle( $style_css, $flip = 'noflip' ) {
3568                 if ( $flip === 'flip' && $this->getLanguage()->isRTL() ) {
3569                         # If wanted, and the interface is right-to-left, flip the CSS
3570                         $style_css = CSSJanus::transform( $style_css, true, false );
3571                 }
3572                 $this->mInlineStyles .= Html::inlineStyle( $style_css );
3573         }
3574
3575         /**
3576          * Build exempt modules and legacy non-ResourceLoader styles.
3577          *
3578          * @return string|WrappedStringList HTML
3579          */
3580         protected function buildExemptModules() {
3581                 $chunks = [];
3582                 // Things that go after the ResourceLoaderDynamicStyles marker
3583                 $append = [];
3584
3585                 // We want site, private and user styles to override dynamically added styles from
3586                 // general modules, but we want dynamically added styles to override statically added
3587                 // style modules. So the order has to be:
3588                 // - page style modules (formatted by ResourceLoaderClientHtml::getHeadHtml())
3589                 // - dynamically loaded styles (added by mw.loader before ResourceLoaderDynamicStyles)
3590                 // - ResourceLoaderDynamicStyles marker
3591                 // - site/private/user styles
3592
3593                 // Add legacy styles added through addStyle()/addInlineStyle() here
3594                 $chunks[] = implode( '', $this->buildCssLinksArray() ) . $this->mInlineStyles;
3595
3596                 $chunks[] = Html::element(
3597                         'meta',
3598                         [ 'name' => 'ResourceLoaderDynamicStyles', 'content' => '' ]
3599                 );
3600
3601                 $separateReq = [ 'site.styles', 'user.styles' ];
3602                 foreach ( $this->rlExemptStyleModules as $group => $moduleNames ) {
3603                         // Combinable modules
3604                         $chunks[] = $this->makeResourceLoaderLink(
3605                                 array_diff( $moduleNames, $separateReq ),
3606                                 ResourceLoaderModule::TYPE_STYLES
3607                         );
3608
3609                         foreach ( array_intersect( $moduleNames, $separateReq ) as $name ) {
3610                                 // These require their own dedicated request in order to support "@import"
3611                                 // syntax, which is incompatible with concatenation. (T147667, T37562)
3612                                 $chunks[] = $this->makeResourceLoaderLink( $name,
3613                                         ResourceLoaderModule::TYPE_STYLES
3614                                 );
3615                         }
3616                 }
3617
3618                 return self::combineWrappedStrings( array_merge( $chunks, $append ) );
3619         }
3620
3621         /**
3622          * @return array
3623          */
3624         public function buildCssLinksArray() {
3625                 $links = [];
3626
3627                 foreach ( $this->styles as $file => $options ) {
3628                         $link = $this->styleLink( $file, $options );
3629                         if ( $link ) {
3630                                 $links[$file] = $link;
3631                         }
3632                 }
3633                 return $links;
3634         }
3635
3636         /**
3637          * Generate \<link\> tags for stylesheets
3638          *
3639          * @param string $style URL to the file
3640          * @param array $options Option, can contain 'condition', 'dir', 'media' keys
3641          * @return string HTML fragment
3642          */
3643         protected function styleLink( $style, array $options ) {
3644                 if ( isset( $options['dir'] ) ) {
3645                         if ( $this->getLanguage()->getDir() != $options['dir'] ) {
3646                                 return '';
3647                         }
3648                 }
3649
3650                 if ( isset( $options['media'] ) ) {
3651                         $media = self::transformCssMedia( $options['media'] );
3652                         if ( is_null( $media ) ) {
3653                                 return '';
3654                         }
3655                 } else {
3656                         $media = 'all';
3657                 }
3658
3659                 if ( substr( $style, 0, 1 ) == '/' ||
3660                         substr( $style, 0, 5 ) == 'http:' ||
3661                         substr( $style, 0, 6 ) == 'https:' ) {
3662                         $url = $style;
3663                 } else {
3664                         $config = $this->getConfig();
3665                         // Append file hash as query parameter
3666                         $url = self::transformResourcePath(
3667                                 $config,
3668                                 $config->get( 'StylePath' ) . '/' . $style
3669                         );
3670                 }
3671
3672                 $link = Html::linkedStyle( $url, $media );
3673
3674                 if ( isset( $options['condition'] ) ) {
3675                         $condition = htmlspecialchars( $options['condition'] );
3676                         $link = "<!--[if $condition]>$link<![endif]-->";
3677                 }
3678                 return $link;
3679         }
3680
3681         /**
3682          * Transform path to web-accessible static resource.
3683          *
3684          * This is used to add a validation hash as query string.
3685          * This aids various behaviors:
3686          *
3687          * - Put long Cache-Control max-age headers on responses for improved
3688          *   cache performance.
3689          * - Get the correct version of a file as expected by the current page.
3690          * - Instantly get the updated version of a file after deployment.
3691          *
3692          * Avoid using this for urls included in HTML as otherwise clients may get different
3693          * versions of a resource when navigating the site depending on when the page was cached.
3694          * If changes to the url propagate, this is not a problem (e.g. if the url is in
3695          * an external stylesheet).
3696          *
3697          * @since 1.27
3698          * @param Config $config
3699          * @param string $path Path-absolute URL to file (from document root, must start with "/")
3700          * @return string URL
3701          */
3702         public static function transformResourcePath( Config $config, $path ) {
3703                 global $IP;
3704
3705                 $localDir = $IP;
3706                 $remotePathPrefix = $config->get( 'ResourceBasePath' );
3707                 if ( $remotePathPrefix === '' ) {
3708                         // The configured base path is required to be empty string for
3709                         // wikis in the domain root
3710                         $remotePath = '/';
3711                 } else {
3712                         $remotePath = $remotePathPrefix;
3713                 }
3714                 if ( strpos( $path, $remotePath ) !== 0 || substr( $path, 0, 2 ) === '//' ) {
3715                         // - Path is outside wgResourceBasePath, ignore.
3716                         // - Path is protocol-relative. Fixes T155310. Not supported by RelPath lib.
3717                         return $path;
3718                 }
3719                 // For files in resources, extensions/ or skins/, ResourceBasePath is preferred here.
3720                 // For other misc files in $IP, we'll fallback to that as well. There is, however, a fourth
3721                 // supported dir/path pair in the configuration (wgUploadDirectory, wgUploadPath)
3722                 // which is not expected to be in wgResourceBasePath on CDNs. (T155146)
3723                 $uploadPath = $config->get( 'UploadPath' );
3724                 if ( strpos( $path, $uploadPath ) === 0 ) {
3725                         $localDir = $config->get( 'UploadDirectory' );
3726                         $remotePathPrefix = $remotePath = $uploadPath;
3727                 }
3728
3729                 $path = RelPath::getRelativePath( $path, $remotePath );
3730                 return self::transformFilePath( $remotePathPrefix, $localDir, $path );
3731         }
3732
3733         /**
3734          * Utility method for transformResourceFilePath().
3735          *
3736          * Caller is responsible for ensuring the file exists. Emits a PHP warning otherwise.
3737          *
3738          * @since 1.27
3739          * @param string $remotePathPrefix URL path prefix that points to $localPath
3740          * @param string $localPath File directory exposed at $remotePath
3741          * @param string $file Path to target file relative to $localPath
3742          * @return string URL
3743          */
3744         public static function transformFilePath( $remotePathPrefix, $localPath, $file ) {
3745                 $hash = md5_file( "$localPath/$file" );
3746                 if ( $hash === false ) {
3747                         wfLogWarning( __METHOD__ . ": Failed to hash $localPath/$file" );
3748                         $hash = '';
3749                 }
3750                 return "$remotePathPrefix/$file?" . substr( $hash, 0, 5 );
3751         }
3752
3753         /**
3754          * Transform "media" attribute based on request parameters
3755          *
3756          * @param string $media Current value of the "media" attribute
3757          * @return string Modified value of the "media" attribute, or null to skip
3758          * this stylesheet
3759          */
3760         public static function transformCssMedia( $media ) {
3761                 global $wgRequest;
3762
3763                 // https://www.w3.org/TR/css3-mediaqueries/#syntax
3764                 $screenMediaQueryRegex = '/^(?:only\s+)?screen\b/i';
3765
3766                 // Switch in on-screen display for media testing
3767                 $switches = [
3768                         'printable' => 'print',
3769                         'handheld' => 'handheld',
3770                 ];
3771                 foreach ( $switches as $switch => $targetMedia ) {
3772                         if ( $wgRequest->getBool( $switch ) ) {
3773                                 if ( $media == $targetMedia ) {
3774                                         $media = '';
3775                                 } elseif ( preg_match( $screenMediaQueryRegex, $media ) === 1 ) {
3776                                         /* This regex will not attempt to understand a comma-separated media_query_list
3777                                          *
3778                                          * Example supported values for $media:
3779                                          * 'screen', 'only screen', 'screen and (min-width: 982px)' ),
3780                                          * Example NOT supported value for $media:
3781                                          * '3d-glasses, screen, print and resolution > 90dpi'
3782                                          *
3783                                          * If it's a print request, we never want any kind of screen stylesheets
3784                                          * If it's a handheld request (currently the only other choice with a switch),
3785                                          * we don't want simple 'screen' but we might want screen queries that
3786                                          * have a max-width or something, so we'll pass all others on and let the
3787                                          * client do the query.
3788                                          */
3789                                         if ( $targetMedia == 'print' || $media == 'screen' ) {
3790                                                 return null;
3791                                         }
3792                                 }
3793                         }
3794                 }
3795
3796                 return $media;
3797         }
3798
3799         /**
3800          * Add a wikitext-formatted message to the output.
3801          * This is equivalent to:
3802          *
3803          *    $wgOut->addWikiText( wfMessage( ... )->plain() )
3804          */
3805         public function addWikiMsg( /*...*/ ) {
3806                 $args = func_get_args();
3807                 $name = array_shift( $args );
3808                 $this->addWikiMsgArray( $name, $args );
3809         }
3810
3811         /**
3812          * Add a wikitext-formatted message to the output.
3813          * Like addWikiMsg() except the parameters are taken as an array
3814          * instead of a variable argument list.
3815          *
3816          * @param string $name
3817          * @param array $args
3818          */
3819         public function addWikiMsgArray( $name, $args ) {
3820                 $this->addHTML( $this->msg( $name, $args )->parseAsBlock() );
3821         }
3822
3823         /**
3824          * This function takes a number of message/argument specifications, wraps them in
3825          * some overall structure, and then parses the result and adds it to the output.
3826          *
3827          * In the $wrap, $1 is replaced with the first message, $2 with the second,
3828          * and so on. The subsequent arguments may be either
3829          * 1) strings, in which case they are message names, or
3830          * 2) arrays, in which case, within each array, the first element is the message
3831          *    name, and subsequent elements are the parameters to that message.
3832          *
3833          * Don't use this for messages that are not in the user's interface language.
3834          *
3835          * For example:
3836          *
3837          *    $wgOut->wrapWikiMsg( "<div class='error'>\n$1\n</div>", 'some-error' );
3838          *
3839          * Is equivalent to:
3840          *
3841          *    $wgOut->addWikiText( "<div class='error'>\n"
3842          *        . wfMessage( 'some-error' )->plain() . "\n</div>" );
3843          *
3844          * The newline after the opening div is needed in some wikitext. See T21226.
3845          *
3846          * @param string $wrap
3847          */
3848         public function wrapWikiMsg( $wrap /*, ...*/ ) {
3849                 $msgSpecs = func_get_args();
3850                 array_shift( $msgSpecs );
3851                 $msgSpecs = array_values( $msgSpecs );
3852                 $s = $wrap;
3853                 foreach ( $msgSpecs as $n => $spec ) {
3854                         if ( is_array( $spec ) ) {
3855                                 $args = $spec;
3856                                 $name = array_shift( $args );
3857                                 if ( isset( $args['options'] ) ) {
3858                                         unset( $args['options'] );
3859                                         wfDeprecated(
3860                                                 'Adding "options" to ' . __METHOD__ . ' is no longer supported',
3861                                                 '1.20'
3862                                         );
3863                                 }
3864                         } else {
3865                                 $args = [];
3866                                 $name = $spec;
3867                         }
3868                         $s = str_replace( '$' . ( $n + 1 ), $this->msg( $name, $args )->plain(), $s );
3869                 }
3870                 $this->addWikiText( $s );
3871         }
3872
3873         /**
3874          * Whether the output has a table of contents
3875          * @return bool
3876          * @since 1.22
3877          */
3878         public function isTOCEnabled() {
3879                 return $this->mEnableTOC;
3880         }
3881
3882         /**
3883          * Enables/disables section edit links, doesn't override __NOEDITSECTION__
3884          * @param bool $flag
3885          * @since 1.23
3886          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
3887          */
3888         public function enableSectionEditLinks( $flag = true ) {
3889                 wfDeprecated( __METHOD__, '1.31' );
3890         }
3891
3892         /**
3893          * @return bool
3894          * @since 1.23
3895          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
3896          */
3897         public function sectionEditLinksEnabled() {
3898                 wfDeprecated( __METHOD__, '1.31' );
3899                 return true;
3900         }
3901
3902         /**
3903          * Helper function to setup the PHP implementation of OOUI to use in this request.
3904          *
3905          * @since 1.26
3906          * @param String $skinName The Skin name to determine the correct OOUI theme
3907          * @param String $dir Language direction
3908          */
3909         public static function setupOOUI( $skinName = 'default', $dir = 'ltr' ) {
3910                 $themes = ResourceLoaderOOUIModule::getSkinThemeMap();
3911                 $theme = isset( $themes[$skinName] ) ? $themes[$skinName] : $themes['default'];
3912                 // For example, 'OOUI\WikimediaUITheme'.
3913                 $themeClass = "OOUI\\{$theme}Theme";
3914                 OOUI\Theme::setSingleton( new $themeClass() );
3915                 OOUI\Element::setDefaultDir( $dir );
3916         }
3917
3918         /**
3919          * Add ResourceLoader module styles for OOUI and set up the PHP implementation of it for use with
3920          * MediaWiki and this OutputPage instance.
3921          *
3922          * @since 1.25
3923          */
3924         public function enableOOUI() {
3925                 self::setupOOUI(
3926                         strtolower( $this->getSkin()->getSkinName() ),
3927                         $this->getLanguage()->getDir()
3928                 );
3929                 $this->addModuleStyles( [
3930                         'oojs-ui-core.styles',
3931                         'oojs-ui.styles.indicators',
3932                         'oojs-ui.styles.textures',
3933                         'mediawiki.widgets.styles',
3934                         'oojs-ui.styles.icons-content',
3935                         'oojs-ui.styles.icons-alerts',
3936                         'oojs-ui.styles.icons-interactions',
3937                 ] );
3938         }
3939
3940         /**
3941          * Add Link headers for preloading the wiki's logo.
3942          *
3943          * @since 1.26
3944          */
3945         protected function addLogoPreloadLinkHeaders() {
3946                 $logo = ResourceLoaderSkinModule::getLogo( $this->getConfig() );
3947
3948                 $tags = [];
3949                 $logosPerDppx = [];
3950                 $logos = [];
3951
3952                 if ( !is_array( $logo ) ) {
3953                         // No media queries required if we only have one variant
3954                         $this->addLinkHeader( '<' . $logo . '>;rel=preload;as=image' );
3955                         return;
3956                 }
3957
3958                 if ( isset( $logo['svg'] ) ) {
3959                         // No media queries required if we only have a 1x and svg variant
3960                         // because all preload-capable browsers support SVGs
3961                         $this->addLinkHeader( '<' . $logo['svg'] . '>;rel=preload;as=image' );
3962                         return;
3963                 }
3964
3965                 foreach ( $logo as $dppx => $src ) {
3966                         // Keys are in this format: "1.5x"
3967                         $dppx = substr( $dppx, 0, -1 );
3968                         $logosPerDppx[$dppx] = $src;
3969                 }
3970
3971                 // Because PHP can't have floats as array keys
3972                 uksort( $logosPerDppx, function ( $a , $b ) {
3973                         $a = floatval( $a );
3974                         $b = floatval( $b );
3975
3976                         if ( $a == $b ) {
3977                                 return 0;
3978                         }
3979                         // Sort from smallest to largest (e.g. 1x, 1.5x, 2x)
3980                         return ( $a < $b ) ? -1 : 1;
3981                 } );
3982
3983                 foreach ( $logosPerDppx as $dppx => $src ) {
3984                         $logos[] = [ 'dppx' => $dppx, 'src' => $src ];
3985                 }
3986
3987                 $logosCount = count( $logos );
3988                 // Logic must match ResourceLoaderSkinModule:
3989                 // - 1x applies to resolution < 1.5dppx
3990                 // - 1.5x applies to resolution >= 1.5dppx && < 2dppx
3991                 // - 2x applies to resolution >= 2dppx
3992                 // Note that min-resolution and max-resolution are both inclusive.
3993                 for ( $i = 0; $i < $logosCount; $i++ ) {
3994                         if ( $i === 0 ) {
3995                                 // Smallest dppx
3996                                 // min-resolution is ">=" (larger than or equal to)
3997                                 // "not min-resolution" is essentially "<"
3998                                 $media_query = 'not all and (min-resolution: ' . $logos[ 1 ]['dppx'] . 'dppx)';
3999                         } elseif ( $i !== $logosCount - 1 ) {
4000                                 // In between
4001                                 // Media query expressions can only apply "not" to the entire expression
4002                                 // (e.g. can't express ">= 1.5 and not >= 2).
4003                                 // Workaround: Use <= 1.9999 in place of < 2.
4004                                 $upper_bound = floatval( $logos[ $i + 1 ]['dppx'] ) - 0.000001;
4005                                 $media_query = '(min-resolution: ' . $logos[ $i ]['dppx'] .
4006                                         'dppx) and (max-resolution: ' . $upper_bound . 'dppx)';
4007                         } else {
4008                                 // Largest dppx
4009                                 $media_query = '(min-resolution: ' . $logos[ $i ]['dppx'] . 'dppx)';
4010                         }
4011
4012                         $this->addLinkHeader(
4013                                 '<' . $logos[$i]['src'] . '>;rel=preload;as=image;media=' . $media_query
4014                         );
4015                 }
4016         }
4017
4018         /**
4019          * Get (and set if not yet set) the CSP nonce.
4020          *
4021          * This value needs to be included in any <script> tags on the
4022          * page.
4023          *
4024          * @return string|bool Nonce or false to mean don't output nonce
4025          * @since 1.32
4026          */
4027         public function getCSPNonce() {
4028                 if ( !ContentSecurityPolicy::isEnabled( $this->getConfig() ) ) {
4029                         return false;
4030                 }
4031                 if ( $this->CSPNonce === null ) {
4032                         // XXX It might be expensive to generate randomness
4033                         // on every request, on windows.
4034                         $rand = MWCryptRand::generate( 15 );
4035                         $this->CSPNonce = base64_encode( $rand );
4036                 }
4037                 return $this->CSPNonce;
4038         }
4039 }