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