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\Logger\LoggerFactory;
  24 use MediaWiki\MediaWikiServices;
  25 use MediaWiki\Session\SessionManager;
  26 use Wikimedia\RelPath;
  27 use Wikimedia\WrappedString;
  28 use Wikimedia\WrappedStringList;
  29
  30 /**
  31  * This class should be covered by a general architecture document which does
  32  * not exist as of January 2011.  This is one of the Core classes and should
  33  * be read at least once by any new developers.
  34  *
  35  * This class is used to prepare the final rendering. A skin is then
  36  * applied to the output parameters (links, javascript, html, categories ...).
  37  *
  38  * @todo FIXME: Another class handles sending the whole page to the client.
  39  *
  40  * Some comments comes from a pairing session between Zak Greant and Antoine Musso
  41  * in November 2010.
  42  *
  43  * @todo document
  44  */
  45 class OutputPage extends ContextSource {
  46         /** @var array Should be private. Used with addMeta() which adds "<meta>" */
  47         protected $mMetatags = [];
  48
  49         /** @var array */
  50         protected $mLinktags = [];
  51
  52         /** @var bool */
  53         protected $mCanonicalUrl = false;
  54
  55         /**
  56          * @var string Should be private - has getter and setter. Contains
  57          *   the HTML title */
  58         public $mPagetitle = '';
  59
  60         /**
  61          * @var string Contains all of the "<body>" content. Should be private we
  62          *   got set/get accessors and the append() method.
  63          */
  64         public $mBodytext = '';
  65
  66         /** @var string Stores contents of "<title>" tag */
  67         private $mHTMLtitle = '';
  68
  69         /**
  70          * @var bool Is the displayed content related to the source of the
  71          *   corresponding wiki article.
  72          */
  73         private $mIsarticle = false;
  74
  75         /** @var bool Stores "article flag" toggle. */
  76         private $mIsArticleRelated = true;
  77
  78         /**
  79          * @var bool We have to set isPrintable(). Some pages should
  80          * never be printed (ex: redirections).
  81          */
  82         private $mPrintable = false;
  83
  84         /**
  85          * @var array Contains the page subtitle. Special pages usually have some
  86          *   links here. Don't confuse with site subtitle added by skins.
  87          */
  88         private $mSubtitle = [];
  89
  90         /** @var string */
  91         public $mRedirect = '';
  92
  93         /** @var int */
  94         protected $mStatusCode;
  95
  96         /**
  97          * @var string Used for sending cache control.
  98          *   The whole caching system should probably be moved into its own class.
  99          */
 100         protected $mLastModified = '';
 101
 102         /** @var array */
 103         protected $mCategoryLinks = [];
 104
 105         /** @var array */
 106         protected $mCategories = [
 107                 'hidden' => [],
 108                 'normal' => [],
 109         ];
 110
 111         /** @var array */
 112         protected $mIndicators = [];
 113
 114         /** @var array Array of Interwiki Prefixed (non DB key) Titles (e.g. 'fr:Test page') */
 115         private $mLanguageLinks = [];
 116
 117         /**
 118          * Used for JavaScript (predates ResourceLoader)
 119          * @todo We should split JS / CSS.
 120          * mScripts content is inserted as is in "<head>" by Skin. This might
 121          * contain either a link to a stylesheet or inline CSS.
 122          */
 123         private $mScripts = '';
 124
 125         /** @var string Inline CSS styles. Use addInlineStyle() sparingly */
 126         protected $mInlineStyles = '';
 127
 128         /**
 129          * @var string Used by skin template.
 130          * Example: $tpl->set( 'displaytitle', $out->mPageLinkTitle );
 131          */
 132         public $mPageLinkTitle = '';
 133
 134         /** @var array Array of elements in "<head>". Parser might add its own headers! */
 135         protected $mHeadItems = [];
 136
 137         /** @var array Additional <body> classes; there are also <body> classes from other sources */
 138         protected $mAdditionalBodyClasses = [];
 139
 140         /** @var array */
 141         protected $mModules = [];
 142
 143         /** @var array */
 144         protected $mModuleScripts = [];
 145
 146         /** @var array */
 147         protected $mModuleStyles = [];
 148
 149         /** @var ResourceLoader */
 150         protected $mResourceLoader;
 151
 152         /** @var ResourceLoaderClientHtml */
 153         private $rlClient;
 154
 155         /** @var ResourceLoaderContext */
 156         private $rlClientContext;
 157
 158         /** @var string */
 159         private $rlUserModuleState;
 160
 161         /** @var array */
 162         private $rlExemptStyleModules;
 163
 164         /** @var array */
 165         protected $mJsConfigVars = [];
 166
 167         /** @var array */
 168         protected $mTemplateIds = [];
 169
 170         /** @var array */
 171         protected $mImageTimeKeys = [];
 172
 173         /** @var string */
 174         public $mRedirectCode = '';
 175
 176         protected $mFeedLinksAppendQuery = null;
 177
 178         /** @var array
 179          * What level of 'untrustworthiness' is allowed in CSS/JS modules loaded on this page?
 180          * @see ResourceLoaderModule::$origin
 181          * ResourceLoaderModule::ORIGIN_ALL is assumed unless overridden;
 182          */
 183         protected $mAllowedModules = [
 184                 ResourceLoaderModule::TYPE_COMBINED => ResourceLoaderModule::ORIGIN_ALL,
 185         ];
 186
 187         /** @var bool Whether output is disabled.  If this is true, the 'output' method will do nothing. */
 188         protected $mDoNothing = false;
 189
 190         // Parser related.
 191
 192         /** @var int */
 193         protected $mContainsNewMagic = 0;
 194
 195         /**
 196          * lazy initialised, use parserOptions()
 197          * @var ParserOptions
 198          */
 199         protected $mParserOptions = null;
 200
 201         /**
 202          * Handles the Atom / RSS links.
 203          * We probably only support Atom in 2011.
 204          * @see $wgAdvertisedFeedTypes
 205          */
 206         private $mFeedLinks = [];
 207
 208         // Gwicke work on squid caching? Roughly from 2003.
 209         protected $mEnableClientCache = true;
 210
 211         /** @var bool Flag if output should only contain the body of the article. */
 212         private $mArticleBodyOnly = false;
 213
 214         /** @var bool */
 215         protected $mNewSectionLink = false;
 216
 217         /** @var bool */
 218         protected $mHideNewSectionLink = false;
 219
 220         /**
 221          * @var bool Comes from the parser. This was probably made to load CSS/JS
 222          * only if we had "<gallery>". Used directly in CategoryPage.php.
 223          * Looks like ResourceLoader can replace this.
 224          */
 225         public $mNoGallery = false;
 226
 227         /** @var string */
 228         private $mPageTitleActionText = '';
 229
 230         /** @var int Cache stuff. Looks like mEnableClientCache */
 231         protected $mCdnMaxage = 0;
 232         /** @var int Upper limit on mCdnMaxage */
 233         protected $mCdnMaxageLimit = INF;
 234
 235         /**
 236          * @var bool Controls if anti-clickjacking / frame-breaking headers will
 237          * be sent. This should be done for pages where edit actions are possible.
 238          * Setters: $this->preventClickjacking() and $this->allowClickjacking().
 239          */
 240         protected $mPreventClickjacking = true;
 241
 242         /** @var int To include the variable {{REVISIONID}} */
 243         private $mRevisionId = null;
 244
 245         /** @var string */
 246         private $mRevisionTimestamp = null;
 247
 248         /** @var array */
 249         protected $mFileVersion = null;
 250
 251         /**
 252          * @var array An array of stylesheet filenames (relative from skins path),
 253          * with options for CSS media, IE conditions, and RTL/LTR direction.
 254          * For internal use; add settings in the skin via $this->addStyle()
 255          *
 256          * Style again! This seems like a code duplication since we already have
 257          * mStyles. This is what makes Open Source amazing.
 258          */
 259         protected $styles = [];
 260
 261         private $mIndexPolicy = 'index';
 262         private $mFollowPolicy = 'follow';
 263         private $mVaryHeader = [
 264                 'Accept-Encoding' => [ 'match=gzip' ],
 265         ];
 266
 267         /**
 268          * If the current page was reached through a redirect, $mRedirectedFrom contains the Title
 269          * of the redirect.
 270          *
 271          * @var Title
 272          */
 273         private $mRedirectedFrom = null;
 274
 275         /**
 276          * Additional key => value data
 277          */
 278         private $mProperties = [];
 279
 280         /**
 281          * @var string|null ResourceLoader target for load.php links. If null, will be omitted
 282          */
 283         private $mTarget = null;
 284
 285         /**
 286          * @var bool Whether parser output contains a table of contents
 287          */
 288         private $mEnableTOC = false;
 289
 290         /**
 291          * @var string|null The URL to send in a <link> element with rel=license
 292          */
 293         private $copyrightUrl;
 294
 295         /** @var array Profiling data */
 296         private $limitReportJSData = [];
 297
 298         /**
 299          * Link: header contents
 300          */
 301         private $mLinkHeader = [];
 302
 303         /**
 304          * Constructor for OutputPage. This should not be called directly.
 305          * Instead a new RequestContext should be created and it will implicitly create
 306          * a OutputPage tied to that context.
 307          * @param IContextSource $context
 308          */
 309         function __construct( IContextSource $context ) {
 310                 $this->setContext( $context );
 311         }
 312
 313         /**
 314          * Redirect to $url rather than displaying the normal page
 315          *
 316          * @param string $url
 317          * @param string $responsecode HTTP status code
 318          */
 319         public function redirect( $url, $responsecode = '302' ) {
 320                 # Strip newlines as a paranoia check for header injection in PHP<5.1.2
 321                 $this->mRedirect = str_replace( "\n", '', $url );
 322                 $this->mRedirectCode = $responsecode;
 323         }
 324
 325         /**
 326          * Get the URL to redirect to, or an empty string if not redirect URL set
 327          *
 328          * @return string
 329          */
 330         public function getRedirect() {
 331                 return $this->mRedirect;
 332         }
 333
 334         /**
 335          * Set the copyright URL to send with the output.
 336          * Empty string to omit, null to reset.
 337          *
 338          * @since 1.26
 339          *
 340          * @param string|null $url
 341          */
 342         public function setCopyrightUrl( $url ) {
 343                 $this->copyrightUrl = $url;
 344         }
 345
 346         /**
 347          * Set the HTTP status code to send with the output.
 348          *
 349          * @param int $statusCode
 350          */
 351         public function setStatusCode( $statusCode ) {
 352                 $this->mStatusCode = $statusCode;
 353         }
 354
 355         /**
 356          * Add a new "<meta>" tag
 357          * To add an http-equiv meta tag, precede the name with "http:"
 358          *
 359          * @param string $name Name of the meta tag
 360          * @param string $val Value of the meta tag
 361          */
 362         function addMeta( $name, $val ) {
 363                 array_push( $this->mMetatags, [ $name, $val ] );
 364         }
 365
 366         /**
 367          * Returns the current <meta> tags
 368          *
 369          * @since 1.25
 370          * @return array
 371          */
 372         public function getMetaTags() {
 373                 return $this->mMetatags;
 374         }
 375
 376         /**
 377          * Add a new \<link\> tag to the page header.
 378          *
 379          * Note: use setCanonicalUrl() for rel=canonical.
 380          *
 381          * @param array $linkarr Associative array of attributes.
 382          */
 383         function addLink( array $linkarr ) {
 384                 array_push( $this->mLinktags, $linkarr );
 385         }
 386
 387         /**
 388          * Returns the current <link> tags
 389          *
 390          * @since 1.25
 391          * @return array
 392          */
 393         public function getLinkTags() {
 394                 return $this->mLinktags;
 395         }
 396
 397         /**
 398          * Add a new \<link\> with "rel" attribute set to "meta"
 399          *
 400          * @param array $linkarr Associative array mapping attribute names to their
 401          *                 values, both keys and values will be escaped, and the
 402          *                 "rel" attribute will be automatically added
 403          */
 404         function addMetadataLink( array $linkarr ) {
 405                 $linkarr['rel'] = $this->getMetadataAttribute();
 406                 $this->addLink( $linkarr );
 407         }
 408
 409         /**
 410          * Set the URL to be used for the <link rel=canonical>. This should be used
 411          * in preference to addLink(), to avoid duplicate link tags.
 412          * @param string $url
 413          */
 414         function setCanonicalUrl( $url ) {
 415                 $this->mCanonicalUrl = $url;
 416         }
 417
 418         /**
 419          * Returns the URL to be used for the <link rel=canonical> if
 420          * one is set.
 421          *
 422          * @since 1.25
 423          * @return bool|string
 424          */
 425         public function getCanonicalUrl() {
 426                 return $this->mCanonicalUrl;
 427         }
 428
 429         /**
 430          * Get the value of the "rel" attribute for metadata links
 431          *
 432          * @return string
 433          */
 434         public function getMetadataAttribute() {
 435                 # note: buggy CC software only reads first "meta" link
 436                 static $haveMeta = false;
 437                 if ( $haveMeta ) {
 438                         return 'alternate meta';
 439                 } else {
 440                         $haveMeta = true;
 441                         return 'meta';
 442                 }
 443         }
 444
 445         /**
 446          * Add raw HTML to the list of scripts (including \<script\> tag, etc.)
 447          * Internal use only. Use OutputPage::addModules() or OutputPage::addJsConfigVars()
 448          * if possible.
 449          *
 450          * @param string $script Raw HTML
 451          */
 452         function addScript( $script ) {
 453                 $this->mScripts .= $script;
 454         }
 455
 456         /**
 457          * Add a JavaScript file out of skins/common, or a given relative path.
 458          * Internal use only. Use OutputPage::addModules() if possible.
 459          *
 460          * @param string $file Filename in skins/common or complete on-server path
 461          *              (/foo/bar.js)
 462          * @param string $version Style version of the file. Defaults to $wgStyleVersion
 463          */
 464         public function addScriptFile( $file, $version = null ) {
 465                 // See if $file parameter is an absolute URL or begins with a slash
 466                 if ( substr( $file, 0, 1 ) == '/' || preg_match( '#^[a-z]*://#i', $file ) ) {
 467                         $path = $file;
 468                 } else {
 469                         $path = $this->getConfig()->get( 'StylePath' ) . "/common/{$file}";
 470                 }
 471                 if ( is_null( $version ) ) {
 472                         $version = $this->getConfig()->get( 'StyleVersion' );
 473                 }
 474                 $this->addScript( Html::linkedScript( wfAppendQuery( $path, $version ) ) );
 475         }
 476
 477         /**
 478          * Add a self-contained script tag with the given contents
 479          * Internal use only. Use OutputPage::addModules() if possible.
 480          *
 481          * @param string $script JavaScript text, no script tags
 482          */
 483         public function addInlineScript( $script ) {
 484                 $this->mScripts .= Html::inlineScript( $script );
 485         }
 486
 487         /**
 488          * Filter an array of modules to remove insufficiently trustworthy members, and modules
 489          * which are no longer registered (eg a page is cached before an extension is disabled)
 490          * @param array $modules
 491          * @param string|null $position Unused
 492          * @param string $type
 493          * @return array
 494          */
 495         protected function filterModules( array $modules, $position = null,
 496                 $type = ResourceLoaderModule::TYPE_COMBINED
 497         ) {
 498                 $resourceLoader = $this->getResourceLoader();
 499                 $filteredModules = [];
 500                 foreach ( $modules as $val ) {
 501                         $module = $resourceLoader->getModule( $val );
 502                         if ( $module instanceof ResourceLoaderModule
 503                                 && $module->getOrigin() <= $this->getAllowedModules( $type )
 504                         ) {
 505                                 if ( $this->mTarget && !in_array( $this->mTarget, $module->getTargets() ) ) {
 506                                         $this->warnModuleTargetFilter( $module->getName() );
 507                                         continue;
 508                                 }
 509                                 $filteredModules[] = $val;
 510                         }
 511                 }
 512                 return $filteredModules;
 513         }
 514
 515         private function warnModuleTargetFilter( $moduleName ) {
 516                 static $warnings = [];
 517                 if ( isset( $warnings[$this->mTarget][$moduleName] ) ) {
 518                         return;
 519                 }
 520                 $warnings[$this->mTarget][$moduleName] = true;
 521                 $this->getResourceLoader()->getLogger()->debug(
 522                         'Module "{module}" not loadable on target "{target}".',
 523                         [
 524                                 'module' => $moduleName,
 525                                 'target' => $this->mTarget,
 526                         ]
 527                 );
 528         }
 529
 530         /**
 531          * Get the list of modules to include on this page
 532          *
 533          * @param bool $filter Whether to filter out insufficiently trustworthy modules
 534          * @param string|null $position Unused
 535          * @param string $param
 536          * @param string $type
 537          * @return array Array of module names
 538          */
 539         public function getModules( $filter = false, $position = null, $param = 'mModules',
 540                 $type = ResourceLoaderModule::TYPE_COMBINED
 541         ) {
 542                 $modules = array_values( array_unique( $this->$param ) );
 543                 return $filter
 544                         ? $this->filterModules( $modules, null, $type )
 545                         : $modules;
 546         }
 547
 548         /**
 549          * Add one or more modules recognized by ResourceLoader. Modules added
 550          * through this function will be loaded by ResourceLoader when the
 551          * page loads.
 552          *
 553          * @param string|array $modules Module name (string) or array of module names
 554          */
 555         public function addModules( $modules ) {
 556                 $this->mModules = array_merge( $this->mModules, (array)$modules );
 557         }
 558
 559         /**
 560          * Get the list of module JS to include on this page
 561          *
 562          * @param bool $filter
 563          * @param string|null $position Unused
 564          * @return array Array of module names
 565          */
 566         public function getModuleScripts( $filter = false, $position = null ) {
 567                 return $this->getModules( $filter, null, 'mModuleScripts',
 568                         ResourceLoaderModule::TYPE_SCRIPTS
 569                 );
 570         }
 571
 572         /**
 573          * Add only JS of one or more modules recognized by ResourceLoader. Module
 574          * scripts added through this function will be loaded by ResourceLoader when
 575          * the page loads.
 576          *
 577          * @param string|array $modules Module name (string) or array of module names
 578          */
 579         public function addModuleScripts( $modules ) {
 580                 $this->mModuleScripts = array_merge( $this->mModuleScripts, (array)$modules );
 581         }
 582
 583         /**
 584          * Get the list of module CSS to include on this page
 585          *
 586          * @param bool $filter
 587          * @param string|null $position Unused
 588          * @return array Array of module names
 589          */
 590         public function getModuleStyles( $filter = false, $position = null ) {
 591                 return $this->getModules( $filter, null, 'mModuleStyles',
 592                         ResourceLoaderModule::TYPE_STYLES
 593                 );
 594         }
 595
 596         /**
 597          * Add only CSS of one or more modules recognized by ResourceLoader.
 598          *
 599          * Module styles added through this function will be added using standard link CSS
 600          * tags, rather than as a combined Javascript and CSS package. Thus, they will
 601          * load when JavaScript is disabled (unless CSS also happens to be disabled).
 602          *
 603          * @param string|array $modules Module name (string) or array of module names
 604          */
 605         public function addModuleStyles( $modules ) {
 606                 $this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
 607         }
 608
 609         /**
 610          * @return null|string ResourceLoader target
 611          */
 612         public function getTarget() {
 613                 return $this->mTarget;
 614         }
 615
 616         /**
 617          * Sets ResourceLoader target for load.php links. If null, will be omitted
 618          *
 619          * @param string|null $target
 620          */
 621         public function setTarget( $target ) {
 622                 $this->mTarget = $target;
 623         }
 624
 625         /**
 626          * Get an array of head items
 627          *
 628          * @return array
 629          */
 630         function getHeadItemsArray() {
 631                 return $this->mHeadItems;
 632         }
 633
 634         /**
 635          * Add or replace a head item to the output
 636          *
 637          * Whenever possible, use more specific options like ResourceLoader modules,
 638          * OutputPage::addLink(), OutputPage::addMetaLink() and OutputPage::addFeedLink()
 639          * Fallback options for those are: OutputPage::addStyle, OutputPage::addScript(),
 640          * OutputPage::addInlineScript() and OutputPage::addInlineStyle()
 641          * This would be your very LAST fallback.
 642          *
 643          * @param string $name Item name
 644          * @param string $value Raw HTML
 645          */
 646         public function addHeadItem( $name, $value ) {
 647                 $this->mHeadItems[$name] = $value;
 648         }
 649
 650         /**
 651          * Add one or more head items to the output
 652          *
 653          * @since 1.28
 654          * @param string|string[] $values Raw HTML
 655          */
 656         public function addHeadItems( $values ) {
 657                 $this->mHeadItems = array_merge( $this->mHeadItems, (array)$values );
 658         }
 659
 660         /**
 661          * Check if the header item $name is already set
 662          *
 663          * @param string $name Item name
 664          * @return bool
 665          */
 666         public function hasHeadItem( $name ) {
 667                 return isset( $this->mHeadItems[$name] );
 668         }
 669
 670         /**
 671          * Add a class to the <body> element
 672          *
 673          * @since 1.30
 674          * @param string|string[] $classes One or more classes to add
 675          */
 676         public function addBodyClasses( $classes ) {
 677                 $this->mAdditionalBodyClasses = array_merge( $this->mAdditionalBodyClasses, (array)$classes );
 678         }
 679
 680         /**
 681          * Set whether the output should only contain the body of the article,
 682          * without any skin, sidebar, etc.
 683          * Used e.g. when calling with "action=render".
 684          *
 685          * @param bool $only Whether to output only the body of the article
 686          */
 687         public function setArticleBodyOnly( $only ) {
 688                 $this->mArticleBodyOnly = $only;
 689         }
 690
 691         /**
 692          * Return whether the output will contain only the body of the article
 693          *
 694          * @return bool
 695          */
 696         public function getArticleBodyOnly() {
 697                 return $this->mArticleBodyOnly;
 698         }
 699
 700         /**
 701          * Set an additional output property
 702          * @since 1.21
 703          *
 704          * @param string $name
 705          * @param mixed $value
 706          */
 707         public function setProperty( $name, $value ) {
 708                 $this->mProperties[$name] = $value;
 709         }
 710
 711         /**
 712          * Get an additional output property
 713          * @since 1.21
 714          *
 715          * @param string $name
 716          * @return mixed Property value or null if not found
 717          */
 718         public function getProperty( $name ) {
 719                 if ( isset( $this->mProperties[$name] ) ) {
 720                         return $this->mProperties[$name];
 721                 } else {
 722                         return null;
 723                 }
 724         }
 725
 726         /**
 727          * checkLastModified tells the client to use the client-cached page if
 728          * possible. If successful, the OutputPage is disabled so that
 729          * any future call to OutputPage->output() have no effect.
 730          *
 731          * Side effect: sets mLastModified for Last-Modified header
 732          *
 733          * @param string $timestamp
 734          *
 735          * @return bool True if cache-ok headers was sent.
 736          */
 737         public function checkLastModified( $timestamp ) {
 738                 if ( !$timestamp || $timestamp == '19700101000000' ) {
 739                         wfDebug( __METHOD__ . ": CACHE DISABLED, NO TIMESTAMP\n" );
 740                         return false;
 741                 }
 742                 $config = $this->getConfig();
 743                 if ( !$config->get( 'CachePages' ) ) {
 744                         wfDebug( __METHOD__ . ": CACHE DISABLED\n" );
 745                         return false;
 746                 }
 747
 748                 $timestamp = wfTimestamp( TS_MW, $timestamp );
 749                 $modifiedTimes = [
 750                         'page' => $timestamp,
 751                         'user' => $this->getUser()->getTouched(),
 752                         'epoch' => $config->get( 'CacheEpoch' )
 753                 ];
 754                 if ( $config->get( 'UseSquid' ) ) {
 755                         $modifiedTimes['sepoch'] = wfTimestamp( TS_MW, $this->getCdnCacheEpoch(
 756                                 time(),
 757                                 $config->get( 'SquidMaxage' )
 758                         ) );
 759                 }
 760                 Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this ] );
 761
 762                 $maxModified = max( $modifiedTimes );
 763                 $this->mLastModified = wfTimestamp( TS_RFC2822, $maxModified );
 764
 765                 $clientHeader = $this->getRequest()->getHeader( 'If-Modified-Since' );
 766                 if ( $clientHeader === false ) {
 767                         wfDebug( __METHOD__ . ": client did not send If-Modified-Since header", 'private' );
 768                         return false;
 769                 }
 770
 771                 # IE sends sizes after the date like this:
 772                 # Wed, 20 Aug 2003 06:51:19 GMT; length=5202
 773                 # this breaks strtotime().
 774                 $clientHeader = preg_replace( '/;.*$/', '', $clientHeader );
 775
 776                 Wikimedia\suppressWarnings(); // E_STRICT system time bitching
 777                 $clientHeaderTime = strtotime( $clientHeader );
 778                 Wikimedia\restoreWarnings();
 779                 if ( !$clientHeaderTime ) {
 780                         wfDebug( __METHOD__
 781                                 . ": unable to parse the client's If-Modified-Since header: $clientHeader\n" );
 782                         return false;
 783                 }
 784                 $clientHeaderTime = wfTimestamp( TS_MW, $clientHeaderTime );
 785
 786                 # Make debug info
 787                 $info = '';
 788                 foreach ( $modifiedTimes as $name => $value ) {
 789                         if ( $info !== '' ) {
 790                                 $info .= ', ';
 791                         }
 792                         $info .= "$name=" . wfTimestamp( TS_ISO_8601, $value );
 793                 }
 794
 795                 wfDebug( __METHOD__ . ": client sent If-Modified-Since: " .
 796                         wfTimestamp( TS_ISO_8601, $clientHeaderTime ), 'private' );
 797                 wfDebug( __METHOD__ . ": effective Last-Modified: " .
 798                         wfTimestamp( TS_ISO_8601, $maxModified ), 'private' );
 799                 if ( $clientHeaderTime < $maxModified ) {
 800                         wfDebug( __METHOD__ . ": STALE, $info", 'private' );
 801                         return false;
 802                 }
 803
 804                 # Not modified
 805                 # Give a 304 Not Modified response code and disable body output
 806                 wfDebug( __METHOD__ . ": NOT MODIFIED, $info", 'private' );
 807                 ini_set( 'zlib.output_compression', 0 );
 808                 $this->getRequest()->response()->statusHeader( 304 );
 809                 $this->sendCacheControl();
 810                 $this->disable();
 811
 812                 // Don't output a compressed blob when using ob_gzhandler;
 813                 // it's technically against HTTP spec and seems to confuse
 814                 // Firefox when the response gets split over two packets.
 815                 wfClearOutputBuffers();
 816
 817                 return true;
 818         }
 819
 820         /**
 821          * @param int $reqTime Time of request (eg. now)
 822          * @param int $maxAge Cache TTL in seconds
 823          * @return int Timestamp
 824          */
 825         private function getCdnCacheEpoch( $reqTime, $maxAge ) {
 826                 // Ensure Last-Modified is never more than (wgSquidMaxage) in the past,
 827                 // because even if the wiki page content hasn't changed since, static
 828                 // resources may have changed (skin HTML, interface messages, urls, etc.)
 829                 // and must roll-over in a timely manner (T46570)
 830                 return $reqTime - $maxAge;
 831         }
 832
 833         /**
 834          * Override the last modified timestamp
 835          *
 836          * @param string $timestamp New timestamp, in a format readable by
 837          *        wfTimestamp()
 838          */
 839         public function setLastModified( $timestamp ) {
 840                 $this->mLastModified = wfTimestamp( TS_RFC2822, $timestamp );
 841         }
 842
 843         /**
 844          * Set the robot policy for the page: <http://www.robotstxt.org/meta.html>
 845          *
 846          * @param string $policy The literal string to output as the contents of
 847          *   the meta tag.  Will be parsed according to the spec and output in
 848          *   standardized form.
 849          * @return null
 850          */
 851         public function setRobotPolicy( $policy ) {
 852                 $policy = Article::formatRobotPolicy( $policy );
 853
 854                 if ( isset( $policy['index'] ) ) {
 855                         $this->setIndexPolicy( $policy['index'] );
 856                 }
 857                 if ( isset( $policy['follow'] ) ) {
 858                         $this->setFollowPolicy( $policy['follow'] );
 859                 }
 860         }
 861
 862         /**
 863          * Set the index policy for the page, but leave the follow policy un-
 864          * touched.
 865          *
 866          * @param string $policy Either 'index' or 'noindex'.
 867          * @return null
 868          */
 869         public function setIndexPolicy( $policy ) {
 870                 $policy = trim( $policy );
 871                 if ( in_array( $policy, [ 'index', 'noindex' ] ) ) {
 872                         $this->mIndexPolicy = $policy;
 873                 }
 874         }
 875
 876         /**
 877          * Set the follow policy for the page, but leave the index policy un-
 878          * touched.
 879          *
 880          * @param string $policy Either 'follow' or 'nofollow'.
 881          * @return null
 882          */
 883         public function setFollowPolicy( $policy ) {
 884                 $policy = trim( $policy );
 885                 if ( in_array( $policy, [ 'follow', 'nofollow' ] ) ) {
 886                         $this->mFollowPolicy = $policy;
 887                 }
 888         }
 889
 890         /**
 891          * Set the new value of the "action text", this will be added to the
 892          * "HTML title", separated from it with " - ".
 893          *
 894          * @param string $text New value of the "action text"
 895          */
 896         public function setPageTitleActionText( $text ) {
 897                 $this->mPageTitleActionText = $text;
 898         }
 899
 900         /**
 901          * Get the value of the "action text"
 902          *
 903          * @return string
 904          */
 905         public function getPageTitleActionText() {
 906                 return $this->mPageTitleActionText;
 907         }
 908
 909         /**
 910          * "HTML title" means the contents of "<title>".
 911          * It is stored as plain, unescaped text and will be run through htmlspecialchars in the skin file.
 912          *
 913          * @param string|Message $name
 914          */
 915         public function setHTMLTitle( $name ) {
 916                 if ( $name instanceof Message ) {
 917                         $this->mHTMLtitle = $name->setContext( $this->getContext() )->text();
 918                 } else {
 919                         $this->mHTMLtitle = $name;
 920                 }
 921         }
 922
 923         /**
 924          * Return the "HTML title", i.e. the content of the "<title>" tag.
 925          *
 926          * @return string
 927          */
 928         public function getHTMLTitle() {
 929                 return $this->mHTMLtitle;
 930         }
 931
 932         /**
 933          * Set $mRedirectedFrom, the Title of the page which redirected us to the current page.
 934          *
 935          * @param Title $t
 936          */
 937         public function setRedirectedFrom( $t ) {
 938                 $this->mRedirectedFrom = $t;
 939         }
 940
 941         /**
 942          * "Page title" means the contents of \<h1\>. It is stored as a valid HTML
 943          * fragment. This function allows good tags like \<sup\> in the \<h1\> tag,
 944          * but not bad tags like \<script\>. This function automatically sets
 945          * \<title\> to the same content as \<h1\> but with all tags removed. Bad
 946          * tags that were escaped in \<h1\> will still be escaped in \<title\>, and
 947          * good tags like \<i\> will be dropped entirely.
 948          *
 949          * @param string|Message $name
 950          */
 951         public function setPageTitle( $name ) {
 952                 if ( $name instanceof Message ) {
 953                         $name = $name->setContext( $this->getContext() )->text();
 954                 }
 955
 956                 # change "<script>foo&bar</script>" to "&lt;script&gt;foo&amp;bar&lt;/script&gt;"
 957                 # but leave "<i>foobar</i>" alone
 958                 $nameWithTags = Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $name ) );
 959                 $this->mPagetitle = $nameWithTags;
 960
 961                 # change "<i>foo&amp;bar</i>" to "foo&bar"
 962                 $this->setHTMLTitle(
 963                         $this->msg( 'pagetitle' )->rawParams( Sanitizer::stripAllTags( $nameWithTags ) )
 964                                 ->inContentLanguage()
 965                 );
 966         }
 967
 968         /**
 969          * Return the "page title", i.e. the content of the \<h1\> tag.
 970          *
 971          * @return string
 972          */
 973         public function getPageTitle() {
 974                 return $this->mPagetitle;
 975         }
 976
 977         /**
 978          * Set the Title object to use
 979          *
 980          * @param Title $t
 981          */
 982         public function setTitle( Title $t ) {
 983                 $this->getContext()->setTitle( $t );
 984         }
 985
 986         /**
 987          * Replace the subtitle with $str
 988          *
 989          * @param string|Message $str New value of the subtitle. String should be safe HTML.
 990          */
 991         public function setSubtitle( $str ) {
 992                 $this->clearSubtitle();
 993                 $this->addSubtitle( $str );
 994         }
 995
 996         /**
 997          * Add $str to the subtitle
 998          *
 999          * @param string|Message $str String or Message to add to the subtitle. String should be safe HTML.
1000          */
1001         public function addSubtitle( $str ) {
1002                 if ( $str instanceof Message ) {
1003                         $this->mSubtitle[] = $str->setContext( $this->getContext() )->parse();
1004                 } else {
1005                         $this->mSubtitle[] = $str;
1006                 }
1007         }
1008
1009         /**
1010          * Build message object for a subtitle containing a backlink to a page
1011          *
1012          * @param Title $title Title to link to
1013          * @param array $query Array of additional parameters to include in the link
1014          * @return Message
1015          * @since 1.25
1016          */
1017         public static function buildBacklinkSubtitle( Title $title, $query = [] ) {
1018                 if ( $title->isRedirect() ) {
1019                         $query['redirect'] = 'no';
1020                 }
1021                 $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1022                 return wfMessage( 'backlinksubtitle' )
1023                         ->rawParams( $linkRenderer->makeLink( $title, null, [], $query ) );
1024         }
1025
1026         /**
1027          * Add a subtitle containing a backlink to a page
1028          *
1029          * @param Title $title Title to link to
1030          * @param array $query Array of additional parameters to include in the link
1031          */
1032         public function addBacklinkSubtitle( Title $title, $query = [] ) {
1033                 $this->addSubtitle( self::buildBacklinkSubtitle( $title, $query ) );
1034         }
1035
1036         /**
1037          * Clear the subtitles
1038          */
1039         public function clearSubtitle() {
1040                 $this->mSubtitle = [];
1041         }
1042
1043         /**
1044          * Get the subtitle
1045          *
1046          * @return string
1047          */
1048         public function getSubtitle() {
1049                 return implode( "<br />\n\t\t\t\t", $this->mSubtitle );
1050         }
1051
1052         /**
1053          * Set the page as printable, i.e. it'll be displayed with all
1054          * print styles included
1055          */
1056         public function setPrintable() {
1057                 $this->mPrintable = true;
1058         }
1059
1060         /**
1061          * Return whether the page is "printable"
1062          *
1063          * @return bool
1064          */
1065         public function isPrintable() {
1066                 return $this->mPrintable;
1067         }
1068
1069         /**
1070          * Disable output completely, i.e. calling output() will have no effect
1071          */
1072         public function disable() {
1073                 $this->mDoNothing = true;
1074         }
1075
1076         /**
1077          * Return whether the output will be completely disabled
1078          *
1079          * @return bool
1080          */
1081         public function isDisabled() {
1082                 return $this->mDoNothing;
1083         }
1084
1085         /**
1086          * Show an "add new section" link?
1087          *
1088          * @return bool
1089          */
1090         public function showNewSectionLink() {
1091                 return $this->mNewSectionLink;
1092         }
1093
1094         /**
1095          * Forcibly hide the new section link?
1096          *
1097          * @return bool
1098          */
1099         public function forceHideNewSectionLink() {
1100                 return $this->mHideNewSectionLink;
1101         }
1102
1103         /**
1104          * Add or remove feed links in the page header
1105          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1106          * for the new version
1107          * @see addFeedLink()
1108          *
1109          * @param bool $show True: add default feeds, false: remove all feeds
1110          */
1111         public function setSyndicated( $show = true ) {
1112                 if ( $show ) {
1113                         $this->setFeedAppendQuery( false );
1114                 } else {
1115                         $this->mFeedLinks = [];
1116                 }
1117         }
1118
1119         /**
1120          * Add default feeds to the page header
1121          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1122          * for the new version
1123          * @see addFeedLink()
1124          *
1125          * @param string $val Query to append to feed links or false to output
1126          *        default links
1127          */
1128         public function setFeedAppendQuery( $val ) {
1129                 $this->mFeedLinks = [];
1130
1131                 foreach ( $this->getConfig()->get( 'AdvertisedFeedTypes' ) as $type ) {
1132                         $query = "feed=$type";
1133                         if ( is_string( $val ) ) {
1134                                 $query .= '&' . $val;
1135                         }
1136                         $this->mFeedLinks[$type] = $this->getTitle()->getLocalURL( $query );
1137                 }
1138         }
1139
1140         /**
1141          * Add a feed link to the page header
1142          *
1143          * @param string $format Feed type, should be a key of $wgFeedClasses
1144          * @param string $href URL
1145          */
1146         public function addFeedLink( $format, $href ) {
1147                 if ( in_array( $format, $this->getConfig()->get( 'AdvertisedFeedTypes' ) ) ) {
1148                         $this->mFeedLinks[$format] = $href;
1149                 }
1150         }
1151
1152         /**
1153          * Should we output feed links for this page?
1154          * @return bool
1155          */
1156         public function isSyndicated() {
1157                 return count( $this->mFeedLinks ) > 0;
1158         }
1159
1160         /**
1161          * Return URLs for each supported syndication format for this page.
1162          * @return array Associating format keys with URLs
1163          */
1164         public function getSyndicationLinks() {
1165                 return $this->mFeedLinks;
1166         }
1167
1168         /**
1169          * Will currently always return null
1170          *
1171          * @return null
1172          */
1173         public function getFeedAppendQuery() {
1174                 return $this->mFeedLinksAppendQuery;
1175         }
1176
1177         /**
1178          * Set whether the displayed content is related to the source of the
1179          * corresponding article on the wiki
1180          * Setting true will cause the change "article related" toggle to true
1181          *
1182          * @param bool $v
1183          */
1184         public function setArticleFlag( $v ) {
1185                 $this->mIsarticle = $v;
1186                 if ( $v ) {
1187                         $this->mIsArticleRelated = $v;
1188                 }
1189         }
1190
1191         /**
1192          * Return whether the content displayed page is related to the source of
1193          * the corresponding article on the wiki
1194          *
1195          * @return bool
1196          */
1197         public function isArticle() {
1198                 return $this->mIsarticle;
1199         }
1200
1201         /**
1202          * Set whether this page is related an article on the wiki
1203          * Setting false will cause the change of "article flag" toggle to false
1204          *
1205          * @param bool $v
1206          */
1207         public function setArticleRelated( $v ) {
1208                 $this->mIsArticleRelated = $v;
1209                 if ( !$v ) {
1210                         $this->mIsarticle = false;
1211                 }
1212         }
1213
1214         /**
1215          * Return whether this page is related an article on the wiki
1216          *
1217          * @return bool
1218          */
1219         public function isArticleRelated() {
1220                 return $this->mIsArticleRelated;
1221         }
1222
1223         /**
1224          * Add new language links
1225          *
1226          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1227          *                               (e.g. 'fr:Test page')
1228          */
1229         public function addLanguageLinks( array $newLinkArray ) {
1230                 $this->mLanguageLinks += $newLinkArray;
1231         }
1232
1233         /**
1234          * Reset the language links and add new language links
1235          *
1236          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1237          *                               (e.g. 'fr:Test page')
1238          */
1239         public function setLanguageLinks( array $newLinkArray ) {
1240                 $this->mLanguageLinks = $newLinkArray;
1241         }
1242
1243         /**
1244          * Get the list of language links
1245          *
1246          * @return string[] Array of interwiki-prefixed (non DB key) titles (e.g. 'fr:Test page')
1247          */
1248         public function getLanguageLinks() {
1249                 return $this->mLanguageLinks;
1250         }
1251
1252         /**
1253          * Add an array of categories, with names in the keys
1254          *
1255          * @param array $categories Mapping category name => sort key
1256          */
1257         public function addCategoryLinks( array $categories ) {
1258                 global $wgContLang;
1259
1260                 if ( !is_array( $categories ) || count( $categories ) == 0 ) {
1261                         return;
1262                 }
1263
1264                 $res = $this->addCategoryLinksToLBAndGetResult( $categories );
1265
1266                 # Set all the values to 'normal'.
1267                 $categories = array_fill_keys( array_keys( $categories ), 'normal' );
1268
1269                 # Mark hidden categories
1270                 foreach ( $res as $row ) {
1271                         if ( isset( $row->pp_value ) ) {
1272                                 $categories[$row->page_title] = 'hidden';
1273                         }
1274                 }
1275
1276                 // Avoid PHP 7.1 warning of passing $this by reference
1277                 $outputPage = $this;
1278                 # Add the remaining categories to the skin
1279                 if ( Hooks::run(
1280                         'OutputPageMakeCategoryLinks',
1281                         [ &$outputPage, $categories, &$this->mCategoryLinks ] )
1282                 ) {
1283                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1284                         foreach ( $categories as $category => $type ) {
1285                                 // array keys will cast numeric category names to ints, so cast back to string
1286                                 $category = (string)$category;
1287                                 $origcategory = $category;
1288                                 $title = Title::makeTitleSafe( NS_CATEGORY, $category );
1289                                 if ( !$title ) {
1290                                         continue;
1291                                 }
1292                                 $wgContLang->findVariantLink( $category, $title, true );
1293                                 if ( $category != $origcategory && array_key_exists( $category, $categories ) ) {
1294                                         continue;
1295                                 }
1296                                 $text = $wgContLang->convertHtml( $title->getText() );
1297                                 $this->mCategories[$type][] = $title->getText();
1298                                 $this->mCategoryLinks[$type][] = $linkRenderer->makeLink( $title, new HtmlArmor( $text ) );
1299                         }
1300                 }
1301         }
1302
1303         /**
1304          * @param array $categories
1305          * @return bool|ResultWrapper
1306          */
1307         protected function addCategoryLinksToLBAndGetResult( array $categories ) {
1308                 # Add the links to a LinkBatch
1309                 $arr = [ NS_CATEGORY => $categories ];
1310                 $lb = new LinkBatch;
1311                 $lb->setArray( $arr );
1312
1313                 # Fetch existence plus the hiddencat property
1314                 $dbr = wfGetDB( DB_REPLICA );
1315                 $fields = array_merge(
1316                         LinkCache::getSelectFields(),
1317                         [ 'page_namespace', 'page_title', 'pp_value' ]
1318                 );
1319
1320                 $res = $dbr->select( [ 'page', 'page_props' ],
1321                         $fields,
1322                         $lb->constructSet( 'page', $dbr ),
1323                         __METHOD__,
1324                         [],
1325                         [ 'page_props' => [ 'LEFT JOIN', [
1326                                 'pp_propname' => 'hiddencat',
1327                                 'pp_page = page_id'
1328                         ] ] ]
1329                 );
1330
1331                 # Add the results to the link cache
1332                 $lb->addResultToCache( LinkCache::singleton(), $res );
1333
1334                 return $res;
1335         }
1336
1337         /**
1338          * Reset the category links (but not the category list) and add $categories
1339          *
1340          * @param array $categories Mapping category name => sort key
1341          */
1342         public function setCategoryLinks( array $categories ) {
1343                 $this->mCategoryLinks = [];
1344                 $this->addCategoryLinks( $categories );
1345         }
1346
1347         /**
1348          * Get the list of category links, in a 2-D array with the following format:
1349          * $arr[$type][] = $link, where $type is either "normal" or "hidden" (for
1350          * hidden categories) and $link a HTML fragment with a link to the category
1351          * page
1352          *
1353          * @return array
1354          */
1355         public function getCategoryLinks() {
1356                 return $this->mCategoryLinks;
1357         }
1358
1359         /**
1360          * Get the list of category names this page belongs to.
1361          *
1362          * @param string $type The type of categories which should be returned. Possible values:
1363          *  * all: all categories of all types
1364          *  * hidden: only the hidden categories
1365          *  * normal: all categories, except hidden categories
1366          * @return array Array of strings
1367          */
1368         public function getCategories( $type = 'all' ) {
1369                 if ( $type === 'all' ) {
1370                         $allCategories = [];
1371                         foreach ( $this->mCategories as $categories ) {
1372                                 $allCategories = array_merge( $allCategories, $categories );
1373                         }
1374                         return $allCategories;
1375                 }
1376                 if ( !isset( $this->mCategories[$type] ) ) {
1377                         throw new InvalidArgumentException( 'Invalid category type given: ' . $type );
1378                 }
1379                 return $this->mCategories[$type];
1380         }
1381
1382         /**
1383          * Add an array of indicators, with their identifiers as array
1384          * keys and HTML contents as values.
1385          *
1386          * In case of duplicate keys, existing values are overwritten.
1387          *
1388          * @param array $indicators
1389          * @since 1.25
1390          */
1391         public function setIndicators( array $indicators ) {
1392                 $this->mIndicators = $indicators + $this->mIndicators;
1393                 // Keep ordered by key
1394                 ksort( $this->mIndicators );
1395         }
1396
1397         /**
1398          * Get the indicators associated with this page.
1399          *
1400          * The array will be internally ordered by item keys.
1401          *
1402          * @return array Keys: identifiers, values: HTML contents
1403          * @since 1.25
1404          */
1405         public function getIndicators() {
1406                 return $this->mIndicators;
1407         }
1408
1409         /**
1410          * Adds help link with an icon via page indicators.
1411          * Link target can be overridden by a local message containing a wikilink:
1412          * the message key is: lowercase action or special page name + '-helppage'.
1413          * @param string $to Target MediaWiki.org page title or encoded URL.
1414          * @param bool $overrideBaseUrl Whether $url is a full URL, to avoid MW.o.
1415          * @since 1.25
1416          */
1417         public function addHelpLink( $to, $overrideBaseUrl = false ) {
1418                 $this->addModuleStyles( 'mediawiki.helplink' );
1419                 $text = $this->msg( 'helppage-top-gethelp' )->escaped();
1420
1421                 if ( $overrideBaseUrl ) {
1422                         $helpUrl = $to;
1423                 } else {
1424                         $toUrlencoded = wfUrlencode( str_replace( ' ', '_', $to ) );
1425                         $helpUrl = "//www.mediawiki.org/wiki/Special:MyLanguage/$toUrlencoded";
1426                 }
1427
1428                 $link = Html::rawElement(
1429                         'a',
1430                         [
1431                                 'href' => $helpUrl,
1432                                 'target' => '_blank',
1433                                 'class' => 'mw-helplink',
1434                         ],
1435                         $text
1436                 );
1437
1438                 $this->setIndicators( [ 'mw-helplink' => $link ] );
1439         }
1440
1441         /**
1442          * Do not allow scripts which can be modified by wiki users to load on this page;
1443          * only allow scripts bundled with, or generated by, the software.
1444          * Site-wide styles are controlled by a config setting, since they can be
1445          * used to create a custom skin/theme, but not user-specific ones.
1446          *
1447          * @todo this should be given a more accurate name
1448          */
1449         public function disallowUserJs() {
1450                 $this->reduceAllowedModules(
1451                         ResourceLoaderModule::TYPE_SCRIPTS,
1452                         ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
1453                 );
1454
1455                 // Site-wide styles are controlled by a config setting, see T73621
1456                 // for background on why. User styles are never allowed.
1457                 if ( $this->getConfig()->get( 'AllowSiteCSSOnRestrictedPages' ) ) {
1458                         $styleOrigin = ResourceLoaderModule::ORIGIN_USER_SITEWIDE;
1459                 } else {
1460                         $styleOrigin = ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL;
1461                 }
1462                 $this->reduceAllowedModules(
1463                         ResourceLoaderModule::TYPE_STYLES,
1464                         $styleOrigin
1465                 );
1466         }
1467
1468         /**
1469          * Show what level of JavaScript / CSS untrustworthiness is allowed on this page
1470          * @see ResourceLoaderModule::$origin
1471          * @param string $type ResourceLoaderModule TYPE_ constant
1472          * @return int ResourceLoaderModule ORIGIN_ class constant
1473          */
1474         public function getAllowedModules( $type ) {
1475                 if ( $type == ResourceLoaderModule::TYPE_COMBINED ) {
1476                         return min( array_values( $this->mAllowedModules ) );
1477                 } else {
1478                         return isset( $this->mAllowedModules[$type] )
1479                                 ? $this->mAllowedModules[$type]
1480                                 : ResourceLoaderModule::ORIGIN_ALL;
1481                 }
1482         }
1483
1484         /**
1485          * Limit the highest level of CSS/JS untrustworthiness allowed.
1486          *
1487          * If passed the same or a higher level than the current level of untrustworthiness set, the
1488          * level will remain unchanged.
1489          *
1490          * @param string $type
1491          * @param int $level ResourceLoaderModule class constant
1492          */
1493         public function reduceAllowedModules( $type, $level ) {
1494                 $this->mAllowedModules[$type] = min( $this->getAllowedModules( $type ), $level );
1495         }
1496
1497         /**
1498          * Prepend $text to the body HTML
1499          *
1500          * @param string $text HTML
1501          */
1502         public function prependHTML( $text ) {
1503                 $this->mBodytext = $text . $this->mBodytext;
1504         }
1505
1506         /**
1507          * Append $text to the body HTML
1508          *
1509          * @param string $text HTML
1510          */
1511         public function addHTML( $text ) {
1512                 $this->mBodytext .= $text;
1513         }
1514
1515         /**
1516          * Shortcut for adding an Html::element via addHTML.
1517          *
1518          * @since 1.19
1519          *
1520          * @param string $element
1521          * @param array $attribs
1522          * @param string $contents
1523          */
1524         public function addElement( $element, array $attribs = [], $contents = '' ) {
1525                 $this->addHTML( Html::element( $element, $attribs, $contents ) );
1526         }
1527
1528         /**
1529          * Clear the body HTML
1530          */
1531         public function clearHTML() {
1532                 $this->mBodytext = '';
1533         }
1534
1535         /**
1536          * Get the body HTML
1537          *
1538          * @return string HTML
1539          */
1540         public function getHTML() {
1541                 return $this->mBodytext;
1542         }
1543
1544         /**
1545          * Get/set the ParserOptions object to use for wikitext parsing
1546          *
1547          * @param ParserOptions|null $options Either the ParserOption to use or null to only get the
1548          *   current ParserOption object. This parameter is deprecated since 1.31.
1549          * @return ParserOptions
1550          */
1551         public function parserOptions( $options = null ) {
1552                 if ( $options !== null ) {
1553                         wfDeprecated( __METHOD__ . ' with non-null $options', '1.31' );
1554                 }
1555
1556                 if ( $options !== null && !empty( $options->isBogus ) ) {
1557                         // Someone is trying to set a bogus pre-$wgUser PO. Check if it has
1558                         // been changed somehow, and keep it if so.
1559                         $anonPO = ParserOptions::newFromAnon();
1560                         $anonPO->setAllowUnsafeRawHtml( false );
1561                         if ( !$options->matches( $anonPO ) ) {
1562                                 wfLogWarning( __METHOD__ . ': Setting a changed bogus ParserOptions: ' . wfGetAllCallers( 5 ) );
1563                                 $options->isBogus = false;
1564                         }
1565                 }
1566
1567                 if ( !$this->mParserOptions ) {
1568                         if ( !$this->getContext()->getUser()->isSafeToLoad() ) {
1569                                 // $wgUser isn't unstubbable yet, so don't try to get a
1570                                 // ParserOptions for it. And don't cache this ParserOptions
1571                                 // either.
1572                                 $po = ParserOptions::newFromAnon();
1573                                 $po->setAllowUnsafeRawHtml( false );
1574                                 $po->isBogus = true;
1575                                 if ( $options !== null ) {
1576                                         $this->mParserOptions = empty( $options->isBogus ) ? $options : null;
1577                                 }
1578                                 return $po;
1579                         }
1580
1581                         $this->mParserOptions = ParserOptions::newFromContext( $this->getContext() );
1582                         $this->mParserOptions->setAllowUnsafeRawHtml( false );
1583                 }
1584
1585                 if ( $options !== null && !empty( $options->isBogus ) ) {
1586                         // They're trying to restore the bogus pre-$wgUser PO. Do the right
1587                         // thing.
1588                         return wfSetVar( $this->mParserOptions, null, true );
1589                 } else {
1590                         return wfSetVar( $this->mParserOptions, $options );
1591                 }
1592         }
1593
1594         /**
1595          * Set the revision ID which will be seen by the wiki text parser
1596          * for things such as embedded {{REVISIONID}} variable use.
1597          *
1598          * @param int|null $revid An positive integer, or null
1599          * @return mixed Previous value
1600          */
1601         public function setRevisionId( $revid ) {
1602                 $val = is_null( $revid ) ? null : intval( $revid );
1603                 return wfSetVar( $this->mRevisionId, $val );
1604         }
1605
1606         /**
1607          * Get the displayed revision ID
1608          *
1609          * @return int
1610          */
1611         public function getRevisionId() {
1612                 return $this->mRevisionId;
1613         }
1614
1615         /**
1616          * Set the timestamp of the revision which will be displayed. This is used
1617          * to avoid a extra DB call in Skin::lastModified().
1618          *
1619          * @param string|null $timestamp
1620          * @return mixed Previous value
1621          */
1622         public function setRevisionTimestamp( $timestamp ) {
1623                 return wfSetVar( $this->mRevisionTimestamp, $timestamp );
1624         }
1625
1626         /**
1627          * Get the timestamp of displayed revision.
1628          * This will be null if not filled by setRevisionTimestamp().
1629          *
1630          * @return string|null
1631          */
1632         public function getRevisionTimestamp() {
1633                 return $this->mRevisionTimestamp;
1634         }
1635
1636         /**
1637          * Set the displayed file version
1638          *
1639          * @param File|bool $file
1640          * @return mixed Previous value
1641          */
1642         public function setFileVersion( $file ) {
1643                 $val = null;
1644                 if ( $file instanceof File && $file->exists() ) {
1645                         $val = [ 'time' => $file->getTimestamp(), 'sha1' => $file->getSha1() ];
1646                 }
1647                 return wfSetVar( $this->mFileVersion, $val, true );
1648         }
1649
1650         /**
1651          * Get the displayed file version
1652          *
1653          * @return array|null ('time' => MW timestamp, 'sha1' => sha1)
1654          */
1655         public function getFileVersion() {
1656                 return $this->mFileVersion;
1657         }
1658
1659         /**
1660          * Get the templates used on this page
1661          *
1662          * @return array (namespace => dbKey => revId)
1663          * @since 1.18
1664          */
1665         public function getTemplateIds() {
1666                 return $this->mTemplateIds;
1667         }
1668
1669         /**
1670          * Get the files used on this page
1671          *
1672          * @return array (dbKey => array('time' => MW timestamp or null, 'sha1' => sha1 or ''))
1673          * @since 1.18
1674          */
1675         public function getFileSearchOptions() {
1676                 return $this->mImageTimeKeys;
1677         }
1678
1679         /**
1680          * Convert wikitext to HTML and add it to the buffer
1681          * Default assumes that the current page title will be used.
1682          *
1683          * @param string $text
1684          * @param bool $linestart Is this the start of a line?
1685          * @param bool $interface Is this text in the user interface language?
1686          * @throws MWException
1687          */
1688         public function addWikiText( $text, $linestart = true, $interface = true ) {
1689                 $title = $this->getTitle(); // Work around E_STRICT
1690                 if ( !$title ) {
1691                         throw new MWException( 'Title is null' );
1692                 }
1693                 $this->addWikiTextTitle( $text, $title, $linestart, /*tidy*/false, $interface );
1694         }
1695
1696         /**
1697          * Add wikitext with a custom Title object
1698          *
1699          * @param string $text Wikitext
1700          * @param Title &$title
1701          * @param bool $linestart Is this the start of a line?
1702          */
1703         public function addWikiTextWithTitle( $text, &$title, $linestart = true ) {
1704                 $this->addWikiTextTitle( $text, $title, $linestart );
1705         }
1706
1707         /**
1708          * Add wikitext with a custom Title object and tidy enabled.
1709          *
1710          * @param string $text Wikitext
1711          * @param Title &$title
1712          * @param bool $linestart Is this the start of a line?
1713          */
1714         function addWikiTextTitleTidy( $text, &$title, $linestart = true ) {
1715                 $this->addWikiTextTitle( $text, $title, $linestart, true );
1716         }
1717
1718         /**
1719          * Add wikitext with tidy enabled
1720          *
1721          * @param string $text Wikitext
1722          * @param bool $linestart Is this the start of a line?
1723          */
1724         public function addWikiTextTidy( $text, $linestart = true ) {
1725                 $title = $this->getTitle();
1726                 $this->addWikiTextTitleTidy( $text, $title, $linestart );
1727         }
1728
1729         /**
1730          * Add wikitext with a custom Title object
1731          *
1732          * @param string $text Wikitext
1733          * @param Title $title
1734          * @param bool $linestart Is this the start of a line?
1735          * @param bool $tidy Whether to use tidy
1736          * @param bool $interface Whether it is an interface message
1737          *   (for example disables conversion)
1738          */
1739         public function addWikiTextTitle( $text, Title $title, $linestart,
1740                 $tidy = false, $interface = false
1741         ) {
1742                 global $wgParser;
1743
1744                 $popts = $this->parserOptions();
1745                 $oldTidy = $popts->setTidy( $tidy );
1746                 $popts->setInterfaceMessage( (bool)$interface );
1747
1748                 $parserOutput = $wgParser->getFreshParser()->parse(
1749                         $text, $title, $popts,
1750                         $linestart, true, $this->mRevisionId
1751                 );
1752
1753                 $popts->setTidy( $oldTidy );
1754
1755                 $this->addParserOutput( $parserOutput, [
1756                         'enableSectionEditLinks' => false,
1757                 ] );
1758         }
1759
1760         /**
1761          * Add all metadata associated with a ParserOutput object, but without the actual HTML. This
1762          * includes categories, language links, ResourceLoader modules, effects of certain magic words,
1763          * and so on.
1764          *
1765          * @since 1.24
1766          * @param ParserOutput $parserOutput
1767          */
1768         public function addParserOutputMetadata( $parserOutput ) {
1769                 $this->mLanguageLinks += $parserOutput->getLanguageLinks();
1770                 $this->addCategoryLinks( $parserOutput->getCategories() );
1771                 $this->setIndicators( $parserOutput->getIndicators() );
1772                 $this->mNewSectionLink = $parserOutput->getNewSection();
1773                 $this->mHideNewSectionLink = $parserOutput->getHideNewSection();
1774
1775                 if ( !$parserOutput->isCacheable() ) {
1776                         $this->enableClientCache( false );
1777                 }
1778                 $this->mNoGallery = $parserOutput->getNoGallery();
1779                 $this->mHeadItems = array_merge( $this->mHeadItems, $parserOutput->getHeadItems() );
1780                 $this->addModules( $parserOutput->getModules() );
1781                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1782                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1783                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1784                 $this->mPreventClickjacking = $this->mPreventClickjacking
1785                         || $parserOutput->preventClickjacking();
1786
1787                 // Template versioning...
1788                 foreach ( (array)$parserOutput->getTemplateIds() as $ns => $dbks ) {
1789                         if ( isset( $this->mTemplateIds[$ns] ) ) {
1790                                 $this->mTemplateIds[$ns] = $dbks + $this->mTemplateIds[$ns];
1791                         } else {
1792                                 $this->mTemplateIds[$ns] = $dbks;
1793                         }
1794                 }
1795                 // File versioning...
1796                 foreach ( (array)$parserOutput->getFileSearchOptions() as $dbk => $data ) {
1797                         $this->mImageTimeKeys[$dbk] = $data;
1798                 }
1799
1800                 // Hooks registered in the object
1801                 $parserOutputHooks = $this->getConfig()->get( 'ParserOutputHooks' );
1802                 foreach ( $parserOutput->getOutputHooks() as $hookInfo ) {
1803                         list( $hookName, $data ) = $hookInfo;
1804                         if ( isset( $parserOutputHooks[$hookName] ) ) {
1805                                 call_user_func( $parserOutputHooks[$hookName], $this, $parserOutput, $data );
1806                         }
1807                 }
1808
1809                 // Enable OOUI if requested via ParserOutput
1810                 if ( $parserOutput->getEnableOOUI() ) {
1811                         $this->enableOOUI();
1812                 }
1813
1814                 // Include parser limit report
1815                 if ( !$this->limitReportJSData ) {
1816                         $this->limitReportJSData = $parserOutput->getLimitReportJSData();
1817                 }
1818
1819                 // Link flags are ignored for now, but may in the future be
1820                 // used to mark individual language links.
1821                 $linkFlags = [];
1822                 // Avoid PHP 7.1 warning of passing $this by reference
1823                 $outputPage = $this;
1824                 Hooks::run( 'LanguageLinks', [ $this->getTitle(), &$this->mLanguageLinks, &$linkFlags ] );
1825                 Hooks::runWithoutAbort( 'OutputPageParserOutput', [ &$outputPage, $parserOutput ] );
1826
1827                 // This check must be after 'OutputPageParserOutput' runs in addParserOutputMetadata
1828                 // so that extensions may modify ParserOutput to toggle TOC.
1829                 // This cannot be moved to addParserOutputText because that is not
1830                 // called by EditPage for Preview.
1831                 if ( $parserOutput->getTOCHTML() ) {
1832                         $this->mEnableTOC = true;
1833                 }
1834         }
1835
1836         /**
1837          * Add the HTML and enhancements for it (like ResourceLoader modules) associated with a
1838          * ParserOutput object, without any other metadata.
1839          *
1840          * @since 1.24
1841          * @param ParserOutput $parserOutput
1842          * @param array $poOptions Options to ParserOutput::getText()
1843          */
1844         public function addParserOutputContent( $parserOutput, $poOptions = [] ) {
1845                 $this->addParserOutputText( $parserOutput, $poOptions );
1846
1847                 $this->addModules( $parserOutput->getModules() );
1848                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1849                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1850
1851                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1852         }
1853
1854         /**
1855          * Add the HTML associated with a ParserOutput object, without any metadata.
1856          *
1857          * @since 1.24
1858          * @param ParserOutput $parserOutput
1859          * @param array $poOptions Options to ParserOutput::getText()
1860          */
1861         public function addParserOutputText( $parserOutput, $poOptions = [] ) {
1862                 $text = $parserOutput->getText( $poOptions );
1863                 // Avoid PHP 7.1 warning of passing $this by reference
1864                 $outputPage = $this;
1865                 Hooks::runWithoutAbort( 'OutputPageBeforeHTML', [ &$outputPage, &$text ] );
1866                 $this->addHTML( $text );
1867         }
1868
1869         /**
1870          * Add everything from a ParserOutput object.
1871          *
1872          * @param ParserOutput $parserOutput
1873          * @param array $poOptions Options to ParserOutput::getText()
1874          */
1875         function addParserOutput( $parserOutput, $poOptions = [] ) {
1876                 $this->addParserOutputMetadata( $parserOutput );
1877                 $this->addParserOutputText( $parserOutput, $poOptions );
1878         }
1879
1880         /**
1881          * Add the output of a QuickTemplate to the output buffer
1882          *
1883          * @param QuickTemplate &$template
1884          */
1885         public function addTemplate( &$template ) {
1886                 $this->addHTML( $template->getHTML() );
1887         }
1888
1889         /**
1890          * Parse wikitext and return the HTML.
1891          *
1892          * @param string $text
1893          * @param bool $linestart Is this the start of a line?
1894          * @param bool $interface Use interface language ($wgLang instead of
1895          *   $wgContLang) while parsing language sensitive magic words like GRAMMAR and PLURAL.
1896          *   This also disables LanguageConverter.
1897          * @param Language $language Target language object, will override $interface
1898          * @throws MWException
1899          * @return string HTML
1900          */
1901         public function parse( $text, $linestart = true, $interface = false, $language = null ) {
1902                 global $wgParser;
1903
1904                 if ( is_null( $this->getTitle() ) ) {
1905                         throw new MWException( 'Empty $mTitle in ' . __METHOD__ );
1906                 }
1907
1908                 $popts = $this->parserOptions();
1909                 if ( $interface ) {
1910                         $popts->setInterfaceMessage( true );
1911                 }
1912                 if ( $language !== null ) {
1913                         $oldLang = $popts->setTargetLanguage( $language );
1914                 }
1915
1916                 $parserOutput = $wgParser->getFreshParser()->parse(
1917                         $text, $this->getTitle(), $popts,
1918                         $linestart, true, $this->mRevisionId
1919                 );
1920
1921                 if ( $interface ) {
1922                         $popts->setInterfaceMessage( false );
1923                 }
1924                 if ( $language !== null ) {
1925                         $popts->setTargetLanguage( $oldLang );
1926                 }
1927
1928                 return $parserOutput->getText( [
1929                         'enableSectionEditLinks' => false,
1930                 ] );
1931         }
1932
1933         /**
1934          * Parse wikitext, strip paragraphs, and return the HTML.
1935          *
1936          * @param string $text
1937          * @param bool $linestart Is this the start of a line?
1938          * @param bool $interface Use interface language ($wgLang instead of
1939          *   $wgContLang) while parsing language sensitive magic
1940          *   words like GRAMMAR and PLURAL
1941          * @return string HTML
1942          */
1943         public function parseInline( $text, $linestart = true, $interface = false ) {
1944                 $parsed = $this->parse( $text, $linestart, $interface );
1945                 return Parser::stripOuterParagraph( $parsed );
1946         }
1947
1948         /**
1949          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header
1950          *
1951          * @param int $maxage Maximum cache time on the CDN, in seconds.
1952          */
1953         public function setCdnMaxage( $maxage ) {
1954                 $this->mCdnMaxage = min( $maxage, $this->mCdnMaxageLimit );
1955         }
1956
1957         /**
1958          * Lower the value of the "s-maxage" part of the "Cache-control" HTTP header
1959          *
1960          * @param int $maxage Maximum cache time on the CDN, in seconds
1961          * @since 1.27
1962          */
1963         public function lowerCdnMaxage( $maxage ) {
1964                 $this->mCdnMaxageLimit = min( $maxage, $this->mCdnMaxageLimit );
1965                 $this->setCdnMaxage( $this->mCdnMaxage );
1966         }
1967
1968         /**
1969          * Get TTL in [$minTTL,$maxTTL] in pass it to lowerCdnMaxage()
1970          *
1971          * This sets and returns $minTTL if $mtime is false or null. Otherwise,
1972          * the TTL is higher the older the $mtime timestamp is. Essentially, the
1973          * TTL is 90% of the age of the object, subject to the min and max.
1974          *
1975          * @param string|int|float|bool|null $mtime Last-Modified timestamp
1976          * @param int $minTTL Mimimum TTL in seconds [default: 1 minute]
1977          * @param int $maxTTL Maximum TTL in seconds [default: $wgSquidMaxage]
1978          * @return int TTL in seconds
1979          * @since 1.28
1980          */
1981         public function adaptCdnTTL( $mtime, $minTTL = 0, $maxTTL = 0 ) {
1982                 $minTTL = $minTTL ?: IExpiringStore::TTL_MINUTE;
1983                 $maxTTL = $maxTTL ?: $this->getConfig()->get( 'SquidMaxage' );
1984
1985                 if ( $mtime === null || $mtime === false ) {
1986                         return $minTTL; // entity does not exist
1987                 }
1988
1989                 $age = time() - wfTimestamp( TS_UNIX, $mtime );
1990                 $adaptiveTTL = max( 0.9 * $age, $minTTL );
1991                 $adaptiveTTL = min( $adaptiveTTL, $maxTTL );
1992
1993                 $this->lowerCdnMaxage( (int)$adaptiveTTL );
1994
1995                 return $adaptiveTTL;
1996         }
1997
1998         /**
1999          * Use enableClientCache(false) to force it to send nocache headers
2000          *
2001          * @param bool $state
2002          *
2003          * @return bool
2004          */
2005         public function enableClientCache( $state ) {
2006                 return wfSetVar( $this->mEnableClientCache, $state );
2007         }
2008
2009         /**
2010          * Get the list of cookies that will influence on the cache
2011          *
2012          * @return array
2013          */
2014         function getCacheVaryCookies() {
2015                 static $cookies;
2016                 if ( $cookies === null ) {
2017                         $config = $this->getConfig();
2018                         $cookies = array_merge(
2019                                 SessionManager::singleton()->getVaryCookies(),
2020                                 [
2021                                         'forceHTTPS',
2022                                 ],
2023                                 $config->get( 'CacheVaryCookies' )
2024                         );
2025                         Hooks::run( 'GetCacheVaryCookies', [ $this, &$cookies ] );
2026                 }
2027                 return $cookies;
2028         }
2029
2030         /**
2031          * Check if the request has a cache-varying cookie header
2032          * If it does, it's very important that we don't allow public caching
2033          *
2034          * @return bool
2035          */
2036         function haveCacheVaryCookies() {
2037                 $request = $this->getRequest();
2038                 foreach ( $this->getCacheVaryCookies() as $cookieName ) {
2039                         if ( $request->getCookie( $cookieName, '', '' ) !== '' ) {
2040                                 wfDebug( __METHOD__ . ": found $cookieName\n" );
2041                                 return true;
2042                         }
2043                 }
2044                 wfDebug( __METHOD__ . ": no cache-varying cookies found\n" );
2045                 return false;
2046         }
2047
2048         /**
2049          * Add an HTTP header that will influence on the cache
2050          *
2051          * @param string $header Header name
2052          * @param string[]|null $option Options for the Key header. See
2053          * https://datatracker.ietf.org/doc/draft-fielding-http-key/
2054          * for the list of valid options.
2055          */
2056         public function addVaryHeader( $header, array $option = null ) {
2057                 if ( !array_key_exists( $header, $this->mVaryHeader ) ) {
2058                         $this->mVaryHeader[$header] = [];
2059                 }
2060                 if ( !is_array( $option ) ) {
2061                         $option = [];
2062                 }
2063                 $this->mVaryHeader[$header] = array_unique( array_merge( $this->mVaryHeader[$header], $option ) );
2064         }
2065
2066         /**
2067          * Return a Vary: header on which to vary caches. Based on the keys of $mVaryHeader,
2068          * such as Accept-Encoding or Cookie
2069          *
2070          * @return string
2071          */
2072         public function getVaryHeader() {
2073                 // If we vary on cookies, let's make sure it's always included here too.
2074                 if ( $this->getCacheVaryCookies() ) {
2075                         $this->addVaryHeader( 'Cookie' );
2076                 }
2077
2078                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2079                         $this->addVaryHeader( $header, $options );
2080                 }
2081                 return 'Vary: ' . implode( ', ', array_keys( $this->mVaryHeader ) );
2082         }
2083
2084         /**
2085          * Add an HTTP Link: header
2086          *
2087          * @param string $header Header value
2088          */
2089         public function addLinkHeader( $header ) {
2090                 $this->mLinkHeader[] = $header;
2091         }
2092
2093         /**
2094          * Return a Link: header. Based on the values of $mLinkHeader.
2095          *
2096          * @return string
2097          */
2098         public function getLinkHeader() {
2099                 if ( !$this->mLinkHeader ) {
2100                         return false;
2101                 }
2102
2103                 return 'Link: ' . implode( ',', $this->mLinkHeader );
2104         }
2105
2106         /**
2107          * Get a complete Key header
2108          *
2109          * @return string
2110          */
2111         public function getKeyHeader() {
2112                 $cvCookies = $this->getCacheVaryCookies();
2113
2114                 $cookiesOption = [];
2115                 foreach ( $cvCookies as $cookieName ) {
2116                         $cookiesOption[] = 'param=' . $cookieName;
2117                 }
2118                 $this->addVaryHeader( 'Cookie', $cookiesOption );
2119
2120                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2121                         $this->addVaryHeader( $header, $options );
2122                 }
2123
2124                 $headers = [];
2125                 foreach ( $this->mVaryHeader as $header => $option ) {
2126                         $newheader = $header;
2127                         if ( is_array( $option ) && count( $option ) > 0 ) {
2128                                 $newheader .= ';' . implode( ';', $option );
2129                         }
2130                         $headers[] = $newheader;
2131                 }
2132                 $key = 'Key: ' . implode( ',', $headers );
2133
2134                 return $key;
2135         }
2136
2137         /**
2138          * T23672: Add Accept-Language to Vary and Key headers
2139          * if there's no 'variant' parameter existed in GET.
2140          *
2141          * For example:
2142          *   /w/index.php?title=Main_page should always be served; but
2143          *   /w/index.php?title=Main_page&variant=zh-cn should never be served.
2144          */
2145         function addAcceptLanguage() {
2146                 $title = $this->getTitle();
2147                 if ( !$title instanceof Title ) {
2148                         return;
2149                 }
2150
2151                 $lang = $title->getPageLanguage();
2152                 if ( !$this->getRequest()->getCheck( 'variant' ) && $lang->hasVariants() ) {
2153                         $variants = $lang->getVariants();
2154                         $aloption = [];
2155                         foreach ( $variants as $variant ) {
2156                                 if ( $variant === $lang->getCode() ) {
2157                                         continue;
2158                                 } else {
2159                                         $aloption[] = 'substr=' . $variant;
2160
2161                                         // IE and some other browsers use BCP 47 standards in
2162                                         // their Accept-Language header, like "zh-CN" or "zh-Hant".
2163                                         // We should handle these too.
2164                                         $variantBCP47 = LanguageCode::bcp47( $variant );
2165                                         if ( $variantBCP47 !== $variant ) {
2166                                                 $aloption[] = 'substr=' . $variantBCP47;
2167                                         }
2168                                 }
2169                         }
2170                         $this->addVaryHeader( 'Accept-Language', $aloption );
2171                 }
2172         }
2173
2174         /**
2175          * Set a flag which will cause an X-Frame-Options header appropriate for
2176          * edit pages to be sent. The header value is controlled by
2177          * $wgEditPageFrameOptions.
2178          *
2179          * This is the default for special pages. If you display a CSRF-protected
2180          * form on an ordinary view page, then you need to call this function.
2181          *
2182          * @param bool $enable
2183          */
2184         public function preventClickjacking( $enable = true ) {
2185                 $this->mPreventClickjacking = $enable;
2186         }
2187
2188         /**
2189          * Turn off frame-breaking. Alias for $this->preventClickjacking(false).
2190          * This can be called from pages which do not contain any CSRF-protected
2191          * HTML form.
2192          */
2193         public function allowClickjacking() {
2194                 $this->mPreventClickjacking = false;
2195         }
2196
2197         /**
2198          * Get the prevent-clickjacking flag
2199          *
2200          * @since 1.24
2201          * @return bool
2202          */
2203         public function getPreventClickjacking() {
2204                 return $this->mPreventClickjacking;
2205         }
2206
2207         /**
2208          * Get the X-Frame-Options header value (without the name part), or false
2209          * if there isn't one. This is used by Skin to determine whether to enable
2210          * JavaScript frame-breaking, for clients that don't support X-Frame-Options.
2211          *
2212          * @return string|false
2213          */
2214         public function getFrameOptions() {
2215                 $config = $this->getConfig();
2216                 if ( $config->get( 'BreakFrames' ) ) {
2217                         return 'DENY';
2218                 } elseif ( $this->mPreventClickjacking && $config->get( 'EditPageFrameOptions' ) ) {
2219                         return $config->get( 'EditPageFrameOptions' );
2220                 }
2221                 return false;
2222         }
2223
2224         /**
2225          * Send cache control HTTP headers
2226          */
2227         public function sendCacheControl() {
2228                 $response = $this->getRequest()->response();
2229                 $config = $this->getConfig();
2230
2231                 $this->addVaryHeader( 'Cookie' );
2232                 $this->addAcceptLanguage();
2233
2234                 # don't serve compressed data to clients who can't handle it
2235                 # maintain different caches for logged-in users and non-logged in ones
2236                 $response->header( $this->getVaryHeader() );
2237
2238                 if ( $config->get( 'UseKeyHeader' ) ) {
2239                         $response->header( $this->getKeyHeader() );
2240                 }
2241
2242                 if ( $this->mEnableClientCache ) {
2243                         if (
2244                                 $config->get( 'UseSquid' ) &&
2245                                 !$response->hasCookies() &&
2246                                 !SessionManager::getGlobalSession()->isPersistent() &&
2247                                 !$this->isPrintable() &&
2248                                 $this->mCdnMaxage != 0 &&
2249                                 !$this->haveCacheVaryCookies()
2250                         ) {
2251                                 if ( $config->get( 'UseESI' ) ) {
2252                                         # We'll purge the proxy cache explicitly, but require end user agents
2253                                         # to revalidate against the proxy on each visit.
2254                                         # Surrogate-Control controls our CDN, Cache-Control downstream caches
2255                                         wfDebug( __METHOD__ .
2256                                                 ": proxy caching with ESI; {$this->mLastModified} **", 'private' );
2257                                         # start with a shorter timeout for initial testing
2258                                         # header( 'Surrogate-Control: max-age=2678400+2678400, content="ESI/1.0"');
2259                                         $response->header(
2260                                                 "Surrogate-Control: max-age={$config->get( 'SquidMaxage' )}" .
2261                                                 "+{$this->mCdnMaxage}, content=\"ESI/1.0\""
2262                                         );
2263                                         $response->header( 'Cache-Control: s-maxage=0, must-revalidate, max-age=0' );
2264                                 } else {
2265                                         # We'll purge the proxy cache for anons explicitly, but require end user agents
2266                                         # to revalidate against the proxy on each visit.
2267                                         # IMPORTANT! The CDN needs to replace the Cache-Control header with
2268                                         # Cache-Control: s-maxage=0, must-revalidate, max-age=0
2269                                         wfDebug( __METHOD__ .
2270                                                 ": local proxy caching; {$this->mLastModified} **", 'private' );
2271                                         # start with a shorter timeout for initial testing
2272                                         # header( "Cache-Control: s-maxage=2678400, must-revalidate, max-age=0" );
2273                                         $response->header( "Cache-Control: " .
2274                                                 "s-maxage={$this->mCdnMaxage}, must-revalidate, max-age=0" );
2275                                 }
2276                         } else {
2277                                 # We do want clients to cache if they can, but they *must* check for updates
2278                                 # on revisiting the page.
2279                                 wfDebug( __METHOD__ . ": private caching; {$this->mLastModified} **", 'private' );
2280                                 $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2281                                 $response->header( "Cache-Control: private, must-revalidate, max-age=0" );
2282                         }
2283                         if ( $this->mLastModified ) {
2284                                 $response->header( "Last-Modified: {$this->mLastModified}" );
2285                         }
2286                 } else {
2287                         wfDebug( __METHOD__ . ": no caching **", 'private' );
2288
2289                         # In general, the absence of a last modified header should be enough to prevent
2290                         # the client from using its cache. We send a few other things just to make sure.
2291                         $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2292                         $response->header( 'Cache-Control: no-cache, no-store, max-age=0, must-revalidate' );
2293                         $response->header( 'Pragma: no-cache' );
2294                 }
2295         }
2296
2297         /**
2298          * Finally, all the text has been munged and accumulated into
2299          * the object, let's actually output it:
2300          *
2301          * @param bool $return Set to true to get the result as a string rather than sending it
2302          * @return string|null
2303          * @throws Exception
2304          * @throws FatalError
2305          * @throws MWException
2306          */
2307         public function output( $return = false ) {
2308                 global $wgContLang;
2309
2310                 if ( $this->mDoNothing ) {
2311                         return $return ? '' : null;
2312                 }
2313
2314                 $response = $this->getRequest()->response();
2315                 $config = $this->getConfig();
2316
2317                 if ( $this->mRedirect != '' ) {
2318                         # Standards require redirect URLs to be absolute
2319                         $this->mRedirect = wfExpandUrl( $this->mRedirect, PROTO_CURRENT );
2320
2321                         $redirect = $this->mRedirect;
2322                         $code = $this->mRedirectCode;
2323
2324                         if ( Hooks::run( "BeforePageRedirect", [ $this, &$redirect, &$code ] ) ) {
2325                                 if ( $code == '301' || $code == '303' ) {
2326                                         if ( !$config->get( 'DebugRedirects' ) ) {
2327                                                 $response->statusHeader( $code );
2328                                         }
2329                                         $this->mLastModified = wfTimestamp( TS_RFC2822 );
2330                                 }
2331                                 if ( $config->get( 'VaryOnXFP' ) ) {
2332                                         $this->addVaryHeader( 'X-Forwarded-Proto' );
2333                                 }
2334                                 $this->sendCacheControl();
2335
2336                                 $response->header( "Content-Type: text/html; charset=utf-8" );
2337                                 if ( $config->get( 'DebugRedirects' ) ) {
2338                                         $url = htmlspecialchars( $redirect );
2339                                         print "<!DOCTYPE html>\n<html>\n<head>\n<title>Redirect</title>\n</head>\n<body>\n";
2340                                         print "<p>Location: <a href=\"$url\">$url</a></p>\n";
2341                                         print "</body>\n</html>\n";
2342                                 } else {
2343                                         $response->header( 'Location: ' . $redirect );
2344                                 }
2345                         }
2346
2347                         return $return ? '' : null;
2348                 } elseif ( $this->mStatusCode ) {
2349                         $response->statusHeader( $this->mStatusCode );
2350                 }
2351
2352                 # Buffer output; final headers may depend on later processing
2353                 ob_start();
2354
2355                 $response->header( 'Content-type: ' . $config->get( 'MimeType' ) . '; charset=UTF-8' );
2356                 $response->header( 'Content-language: ' . $wgContLang->getHtmlCode() );
2357
2358                 // Avoid Internet Explorer "compatibility view" in IE 8-10, so that
2359                 // jQuery etc. can work correctly.
2360                 $response->header( 'X-UA-Compatible: IE=Edge' );
2361
2362                 if ( !$this->mArticleBodyOnly ) {
2363                         $sk = $this->getSkin();
2364
2365                         if ( $sk->shouldPreloadLogo() ) {
2366                                 $this->addLogoPreloadLinkHeaders();
2367                         }
2368                 }
2369
2370                 $linkHeader = $this->getLinkHeader();
2371                 if ( $linkHeader ) {
2372                         $response->header( $linkHeader );
2373                 }
2374
2375                 // Prevent framing, if requested
2376                 $frameOptions = $this->getFrameOptions();
2377                 if ( $frameOptions ) {
2378                         $response->header( "X-Frame-Options: $frameOptions" );
2379                 }
2380
2381                 if ( $this->mArticleBodyOnly ) {
2382                         echo $this->mBodytext;
2383                 } else {
2384                         // Enable safe mode if requested
2385                         if ( $this->getRequest()->getBool( 'safemode' ) ) {
2386                                 $this->disallowUserJs();
2387                         }
2388
2389                         $sk = $this->getSkin();
2390                         foreach ( $sk->getDefaultModules() as $group ) {
2391                                 $this->addModules( $group );
2392                         }
2393
2394                         MWDebug::addModules( $this );
2395
2396                         // Avoid PHP 7.1 warning of passing $this by reference
2397                         $outputPage = $this;
2398                         // Hook that allows last minute changes to the output page, e.g.
2399                         // adding of CSS or Javascript by extensions.
2400                         Hooks::runWithoutAbort( 'BeforePageDisplay', [ &$outputPage, &$sk ] );
2401
2402                         try {
2403                                 $sk->outputPage();
2404                         } catch ( Exception $e ) {
2405                                 ob_end_clean(); // bug T129657
2406                                 throw $e;
2407                         }
2408                 }
2409
2410                 try {
2411                         // This hook allows last minute changes to final overall output by modifying output buffer
2412                         Hooks::runWithoutAbort( 'AfterFinalPageOutput', [ $this ] );
2413                 } catch ( Exception $e ) {
2414                         ob_end_clean(); // bug T129657
2415                         throw $e;
2416                 }
2417
2418                 $this->sendCacheControl();
2419
2420                 if ( $return ) {
2421                         return ob_get_clean();
2422                 } else {
2423                         ob_end_flush();
2424                         return null;
2425                 }
2426         }
2427
2428         /**
2429          * Prepare this object to display an error page; disable caching and
2430          * indexing, clear the current text and redirect, set the page's title
2431          * and optionally an custom HTML title (content of the "<title>" tag).
2432          *
2433          * @param string|Message $pageTitle Will be passed directly to setPageTitle()
2434          * @param string|Message $htmlTitle Will be passed directly to setHTMLTitle();
2435          *                   optional, if not passed the "<title>" attribute will be
2436          *                   based on $pageTitle
2437          */
2438         public function prepareErrorPage( $pageTitle, $htmlTitle = false ) {
2439                 $this->setPageTitle( $pageTitle );
2440                 if ( $htmlTitle !== false ) {
2441                         $this->setHTMLTitle( $htmlTitle );
2442                 }
2443                 $this->setRobotPolicy( 'noindex,nofollow' );
2444                 $this->setArticleRelated( false );
2445                 $this->enableClientCache( false );
2446                 $this->mRedirect = '';
2447                 $this->clearSubtitle();
2448                 $this->clearHTML();
2449         }
2450
2451         /**
2452          * Output a standard error page
2453          *
2454          * showErrorPage( 'titlemsg', 'pagetextmsg' );
2455          * showErrorPage( 'titlemsg', 'pagetextmsg', [ 'param1', 'param2' ] );
2456          * showErrorPage( 'titlemsg', $messageObject );
2457          * showErrorPage( $titleMessageObject, $messageObject );
2458          *
2459          * @param string|Message $title Message key (string) for page title, or a Message object
2460          * @param string|Message $msg Message key (string) for page text, or a Message object
2461          * @param array $params Message parameters; ignored if $msg is a Message object
2462          */
2463         public function showErrorPage( $title, $msg, $params = [] ) {
2464                 if ( !$title instanceof Message ) {
2465                         $title = $this->msg( $title );
2466                 }
2467
2468                 $this->prepareErrorPage( $title );
2469
2470                 if ( $msg instanceof Message ) {
2471                         if ( $params !== [] ) {
2472                                 trigger_error( 'Argument ignored: $params. The message parameters argument '
2473                                         . 'is discarded when the $msg argument is a Message object instead of '
2474                                         . 'a string.', E_USER_NOTICE );
2475                         }
2476                         $this->addHTML( $msg->parseAsBlock() );
2477                 } else {
2478                         $this->addWikiMsgArray( $msg, $params );
2479                 }
2480
2481                 $this->returnToMain();
2482         }
2483
2484         /**
2485          * Output a standard permission error page
2486          *
2487          * @param array $errors Error message keys or [key, param...] arrays
2488          * @param string $action Action that was denied or null if unknown
2489          */
2490         public function showPermissionsErrorPage( array $errors, $action = null ) {
2491                 foreach ( $errors as $key => $error ) {
2492                         $errors[$key] = (array)$error;
2493                 }
2494
2495                 // For some action (read, edit, create and upload), display a "login to do this action"
2496                 // error if all of the following conditions are met:
2497                 // 1. the user is not logged in
2498                 // 2. the only error is insufficient permissions (i.e. no block or something else)
2499                 // 3. the error can be avoided simply by logging in
2500                 if ( in_array( $action, [ 'read', 'edit', 'createpage', 'createtalk', 'upload' ] )
2501                         && $this->getUser()->isAnon() && count( $errors ) == 1 && isset( $errors[0][0] )
2502                         && ( $errors[0][0] == 'badaccess-groups' || $errors[0][0] == 'badaccess-group0' )
2503                         && ( User::groupHasPermission( 'user', $action )
2504                         || User::groupHasPermission( 'autoconfirmed', $action ) )
2505                 ) {
2506                         $displayReturnto = null;
2507
2508                         # Due to T34276, if a user does not have read permissions,
2509                         # $this->getTitle() will just give Special:Badtitle, which is
2510                         # not especially useful as a returnto parameter. Use the title
2511                         # from the request instead, if there was one.
2512                         $request = $this->getRequest();
2513                         $returnto = Title::newFromText( $request->getVal( 'title', '' ) );
2514                         if ( $action == 'edit' ) {
2515                                 $msg = 'whitelistedittext';
2516                                 $displayReturnto = $returnto;
2517                         } elseif ( $action == 'createpage' || $action == 'createtalk' ) {
2518                                 $msg = 'nocreatetext';
2519                         } elseif ( $action == 'upload' ) {
2520                                 $msg = 'uploadnologintext';
2521                         } else { # Read
2522                                 $msg = 'loginreqpagetext';
2523                                 $displayReturnto = Title::newMainPage();
2524                         }
2525
2526                         $query = [];
2527
2528                         if ( $returnto ) {
2529                                 $query['returnto'] = $returnto->getPrefixedText();
2530
2531                                 if ( !$request->wasPosted() ) {
2532                                         $returntoquery = $request->getValues();
2533                                         unset( $returntoquery['title'] );
2534                                         unset( $returntoquery['returnto'] );
2535                                         unset( $returntoquery['returntoquery'] );
2536                                         $query['returntoquery'] = wfArrayToCgi( $returntoquery );
2537                                 }
2538                         }
2539                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
2540                         $loginLink = $linkRenderer->makeKnownLink(
2541                                 SpecialPage::getTitleFor( 'Userlogin' ),
2542                                 $this->msg( 'loginreqlink' )->text(),
2543                                 [],
2544                                 $query
2545                         );
2546
2547                         $this->prepareErrorPage( $this->msg( 'loginreqtitle' ) );
2548                         $this->addHTML( $this->msg( $msg )->rawParams( $loginLink )->parse() );
2549
2550                         # Don't return to a page the user can't read otherwise
2551                         # we'll end up in a pointless loop
2552                         if ( $displayReturnto && $displayReturnto->userCan( 'read', $this->getUser() ) ) {
2553                                 $this->returnToMain( null, $displayReturnto );
2554                         }
2555                 } else {
2556                         $this->prepareErrorPage( $this->msg( 'permissionserrors' ) );
2557                         $this->addWikiText( $this->formatPermissionsErrorMessage( $errors, $action ) );
2558                 }
2559         }
2560
2561         /**
2562          * Display an error page indicating that a given version of MediaWiki is
2563          * required to use it
2564          *
2565          * @param mixed $version The version of MediaWiki needed to use the page
2566          */
2567         public function versionRequired( $version ) {
2568                 $this->prepareErrorPage( $this->msg( 'versionrequired', $version ) );
2569
2570                 $this->addWikiMsg( 'versionrequiredtext', $version );
2571                 $this->returnToMain();
2572         }
2573
2574         /**
2575          * Format a list of error messages
2576          *
2577          * @param array $errors Array of arrays returned by Title::getUserPermissionsErrors
2578          * @param string $action Action that was denied or null if unknown
2579          * @return string The wikitext error-messages, formatted into a list.
2580          */
2581         public function formatPermissionsErrorMessage( array $errors, $action = null ) {
2582                 if ( $action == null ) {
2583                         $text = $this->msg( 'permissionserrorstext', count( $errors ) )->plain() . "\n\n";
2584                 } else {
2585                         $action_desc = $this->msg( "action-$action" )->plain();
2586                         $text = $this->msg(
2587                                 'permissionserrorstext-withaction',
2588                                 count( $errors ),
2589                                 $action_desc
2590                         )->plain() . "\n\n";
2591                 }
2592
2593                 if ( count( $errors ) > 1 ) {
2594                         $text .= '<ul class="permissions-errors">' . "\n";
2595
2596                         foreach ( $errors as $error ) {
2597                                 $text .= '<li>';
2598                                 $text .= call_user_func_array( [ $this, 'msg' ], $error )->plain();
2599                                 $text .= "</li>\n";
2600                         }
2601                         $text .= '</ul>';
2602                 } else {
2603                         $text .= "<div class=\"permissions-errors\">\n" .
2604                                         call_user_func_array( [ $this, 'msg' ], reset( $errors ) )->plain() .
2605                                         "\n</div>";
2606                 }
2607
2608                 return $text;
2609         }
2610
2611         /**
2612          * Show a warning about replica DB lag
2613          *
2614          * If the lag is higher than $wgSlaveLagCritical seconds,
2615          * then the warning is a bit more obvious. If the lag is
2616          * lower than $wgSlaveLagWarning, then no warning is shown.
2617          *
2618          * @param int $lag Slave lag
2619          */
2620         public function showLagWarning( $lag ) {
2621                 $config = $this->getConfig();
2622                 if ( $lag >= $config->get( 'SlaveLagWarning' ) ) {
2623                         $lag = floor( $lag ); // floor to avoid nano seconds to display
2624                         $message = $lag < $config->get( 'SlaveLagCritical' )
2625                                 ? 'lag-warn-normal'
2626                                 : 'lag-warn-high';
2627                         $wrap = Html::rawElement( 'div', [ 'class' => "mw-{$message}" ], "\n$1\n" );
2628                         $this->wrapWikiMsg( "$wrap\n", [ $message, $this->getLanguage()->formatNum( $lag ) ] );
2629                 }
2630         }
2631
2632         public function showFatalError( $message ) {
2633                 $this->prepareErrorPage( $this->msg( 'internalerror' ) );
2634
2635                 $this->addHTML( $message );
2636         }
2637
2638         public function showUnexpectedValueError( $name, $val ) {
2639                 $this->showFatalError( $this->msg( 'unexpected', $name, $val )->text() );
2640         }
2641
2642         public function showFileCopyError( $old, $new ) {
2643                 $this->showFatalError( $this->msg( 'filecopyerror', $old, $new )->text() );
2644         }
2645
2646         public function showFileRenameError( $old, $new ) {
2647                 $this->showFatalError( $this->msg( 'filerenameerror', $old, $new )->text() );
2648         }
2649
2650         public function showFileDeleteError( $name ) {
2651                 $this->showFatalError( $this->msg( 'filedeleteerror', $name )->text() );
2652         }
2653
2654         public function showFileNotFoundError( $name ) {
2655                 $this->showFatalError( $this->msg( 'filenotfound', $name )->text() );
2656         }
2657
2658         /**
2659          * Add a "return to" link pointing to a specified title
2660          *
2661          * @param Title $title Title to link
2662          * @param array $query Query string parameters
2663          * @param string $text Text of the link (input is not escaped)
2664          * @param array $options Options array to pass to Linker
2665          */
2666         public function addReturnTo( $title, array $query = [], $text = null, $options = [] ) {
2667                 $linkRenderer = MediaWikiServices::getInstance()
2668                         ->getLinkRendererFactory()->createFromLegacyOptions( $options );
2669                 $link = $this->msg( 'returnto' )->rawParams(
2670                         $linkRenderer->makeLink( $title, $text, [], $query ) )->escaped();
2671                 $this->addHTML( "<p id=\"mw-returnto\">{$link}</p>\n" );
2672         }
2673
2674         /**
2675          * Add a "return to" link pointing to a specified title,
2676          * or the title indicated in the request, or else the main page
2677          *
2678          * @param mixed $unused
2679          * @param Title|string $returnto Title or String to return to
2680          * @param string $returntoquery Query string for the return to link
2681          */
2682         public function returnToMain( $unused = null, $returnto = null, $returntoquery = null ) {
2683                 if ( $returnto == null ) {
2684                         $returnto = $this->getRequest()->getText( 'returnto' );
2685                 }
2686
2687                 if ( $returntoquery == null ) {
2688                         $returntoquery = $this->getRequest()->getText( 'returntoquery' );
2689                 }
2690
2691                 if ( $returnto === '' ) {
2692                         $returnto = Title::newMainPage();
2693                 }
2694
2695                 if ( is_object( $returnto ) ) {
2696                         $titleObj = $returnto;
2697                 } else {
2698                         $titleObj = Title::newFromText( $returnto );
2699                 }
2700                 // We don't want people to return to external interwiki. That
2701                 // might potentially be used as part of a phishing scheme
2702                 if ( !is_object( $titleObj ) || $titleObj->isExternal() ) {
2703                         $titleObj = Title::newMainPage();
2704                 }
2705
2706                 $this->addReturnTo( $titleObj, wfCgiToArray( $returntoquery ) );
2707         }
2708
2709         private function getRlClientContext() {
2710                 if ( !$this->rlClientContext ) {
2711                         $query = ResourceLoader::makeLoaderQuery(
2712                                 [], // modules; not relevant
2713                                 $this->getLanguage()->getCode(),
2714                                 $this->getSkin()->getSkinName(),
2715                                 $this->getUser()->isLoggedIn() ? $this->getUser()->getName() : null,
2716                                 null, // version; not relevant
2717                                 ResourceLoader::inDebugMode(),
2718                                 null, // only; not relevant
2719                                 $this->isPrintable(),
2720                                 $this->getRequest()->getBool( 'handheld' )
2721                         );
2722                         $this->rlClientContext = new ResourceLoaderContext(
2723                                 $this->getResourceLoader(),
2724                                 new FauxRequest( $query )
2725                         );
2726                 }
2727                 return $this->rlClientContext;
2728         }
2729
2730         /**
2731          * Call this to freeze the module queue and JS config and create a formatter.
2732          *
2733          * Depending on the Skin, this may get lazy-initialised in either headElement() or
2734          * getBottomScripts(). See SkinTemplate::prepareQuickTemplate(). Calling this too early may
2735          * cause unexpected side-effects since disallowUserJs() may be called at any time to change
2736          * the module filters retroactively. Skins and extension hooks may also add modules until very
2737          * late in the request lifecycle.
2738          *
2739          * @return ResourceLoaderClientHtml
2740          */
2741         public function getRlClient() {
2742                 if ( !$this->rlClient ) {
2743                         $context = $this->getRlClientContext();
2744                         $rl = $this->getResourceLoader();
2745                         $this->addModules( [
2746                                 'user.options',
2747                                 'user.tokens',
2748                         ] );
2749                         $this->addModuleStyles( [
2750                                 'site.styles',
2751                                 'noscript',
2752                                 'user.styles',
2753                         ] );
2754                         $this->getSkin()->setupSkinUserCss( $this );
2755
2756                         // Prepare exempt modules for buildExemptModules()
2757                         $exemptGroups = [ 'site' => [], 'noscript' => [], 'private' => [], 'user' => [] ];
2758                         $exemptStates = [];
2759                         $moduleStyles = $this->getModuleStyles( /*filter*/ true );
2760
2761                         // Preload getTitleInfo for isKnownEmpty calls below and in ResourceLoaderClientHtml
2762                         // Separate user-specific batch for improved cache-hit ratio.
2763                         $userBatch = [ 'user.styles', 'user' ];
2764                         $siteBatch = array_diff( $moduleStyles, $userBatch );
2765                         $dbr = wfGetDB( DB_REPLICA );
2766                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $siteBatch );
2767                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $userBatch );
2768
2769                         // Filter out modules handled by buildExemptModules()
2770                         $moduleStyles = array_filter( $moduleStyles,
2771                                 function ( $name ) use ( $rl, $context, &$exemptGroups, &$exemptStates ) {
2772                                         $module = $rl->getModule( $name );
2773                                         if ( $module ) {
2774                                                 if ( $name === 'user.styles' && $this->isUserCssPreview() ) {
2775                                                         $exemptStates[$name] = 'ready';
2776                                                         // Special case in buildExemptModules()
2777                                                         return false;
2778                                                 }
2779                                                 $group = $module->getGroup();
2780                                                 if ( isset( $exemptGroups[$group] ) ) {
2781                                                         $exemptStates[$name] = 'ready';
2782                                                         if ( !$module->isKnownEmpty( $context ) ) {
2783                                                                 // E.g. Don't output empty <styles>
2784                                                                 $exemptGroups[$group][] = $name;
2785                                                         }
2786                                                         return false;
2787                                                 }
2788                                         }
2789                                         return true;
2790                                 }
2791                         );
2792                         $this->rlExemptStyleModules = $exemptGroups;
2793
2794                         $isUserModuleFiltered = !$this->filterModules( [ 'user' ] );
2795                         // If this page filters out 'user', makeResourceLoaderLink will drop it.
2796                         // Avoid indefinite "loading" state or untrue "ready" state (T145368).
2797                         if ( !$isUserModuleFiltered ) {
2798                                 // Manually handled by getBottomScripts()
2799                                 $userModule = $rl->getModule( 'user' );
2800                                 $userState = $userModule->isKnownEmpty( $context ) && !$this->isUserJsPreview()
2801                                         ? 'ready'
2802                                         : 'loading';
2803                                 $this->rlUserModuleState = $exemptStates['user'] = $userState;
2804                         }
2805
2806                         $rlClient = new ResourceLoaderClientHtml( $context, [
2807                                 'target' => $this->getTarget(),
2808                         ] );
2809                         $rlClient->setConfig( $this->getJSVars() );
2810                         $rlClient->setModules( $this->getModules( /*filter*/ true ) );
2811                         $rlClient->setModuleStyles( $moduleStyles );
2812                         $rlClient->setModuleScripts( $this->getModuleScripts( /*filter*/ true ) );
2813                         $rlClient->setExemptStates( $exemptStates );
2814                         $this->rlClient = $rlClient;
2815                 }
2816                 return $this->rlClient;
2817         }
2818
2819         /**
2820          * @param Skin $sk The given Skin
2821          * @param bool $includeStyle Unused
2822          * @return string The doctype, opening "<html>", and head element.
2823          */
2824         public function headElement( Skin $sk, $includeStyle = true ) {
2825                 global $wgContLang;
2826
2827                 $userdir = $this->getLanguage()->getDir();
2828                 $sitedir = $wgContLang->getDir();
2829
2830                 $pieces = [];
2831                 $pieces[] = Html::htmlHeader( Sanitizer::mergeAttributes(
2832                         $this->getRlClient()->getDocumentAttributes(),
2833                         $sk->getHtmlElementAttributes()
2834                 ) );
2835                 $pieces[] = Html::openElement( 'head' );
2836
2837                 if ( $this->getHTMLTitle() == '' ) {
2838                         $this->setHTMLTitle( $this->msg( 'pagetitle', $this->getPageTitle() )->inContentLanguage() );
2839                 }
2840
2841                 if ( !Html::isXmlMimeType( $this->getConfig()->get( 'MimeType' ) ) ) {
2842                         // Add <meta charset="UTF-8">
2843                         // This should be before <title> since it defines the charset used by
2844                         // text including the text inside <title>.
2845                         // The spec recommends defining XHTML5's charset using the XML declaration
2846                         // instead of meta.
2847                         // Our XML declaration is output by Html::htmlHeader.
2848                         // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-content-type
2849                         // https://html.spec.whatwg.org/multipage/semantics.html#charset
2850                         $pieces[] = Html::element( 'meta', [ 'charset' => 'UTF-8' ] );
2851                 }
2852
2853                 $pieces[] = Html::element( 'title', null, $this->getHTMLTitle() );
2854                 $pieces[] = $this->getRlClient()->getHeadHtml();
2855                 $pieces[] = $this->buildExemptModules();
2856                 $pieces = array_merge( $pieces, array_values( $this->getHeadLinksArray() ) );
2857                 $pieces = array_merge( $pieces, array_values( $this->mHeadItems ) );
2858
2859                 // Use an IE conditional comment to serve the script only to old IE
2860                 $pieces[] = '<!--[if lt IE 9]>' .
2861                         ResourceLoaderClientHtml::makeLoad(
2862                                 ResourceLoaderContext::newDummyContext(),
2863                                 [ 'html5shiv' ],
2864                                 ResourceLoaderModule::TYPE_SCRIPTS,
2865                                 [ 'sync' => true ]
2866                         ) .
2867                         '<![endif]-->';
2868
2869                 $pieces[] = Html::closeElement( 'head' );
2870
2871                 $bodyClasses = $this->mAdditionalBodyClasses;
2872                 $bodyClasses[] = 'mediawiki';
2873
2874                 # Classes for LTR/RTL directionality support
2875                 $bodyClasses[] = $userdir;
2876                 $bodyClasses[] = "sitedir-$sitedir";
2877
2878                 $underline = $this->getUser()->getOption( 'underline' );
2879                 if ( $underline < 2 ) {
2880                         // The following classes can be used here:
2881                         // * mw-underline-always
2882                         // * mw-underline-never
2883                         $bodyClasses[] = 'mw-underline-' . ( $underline ? 'always' : 'never' );
2884                 }
2885
2886                 if ( $this->getLanguage()->capitalizeAllNouns() ) {
2887                         # A <body> class is probably not the best way to do this . . .
2888                         $bodyClasses[] = 'capitalize-all-nouns';
2889                 }
2890
2891                 // Parser feature migration class
2892                 // The idea is that this will eventually be removed, after the wikitext
2893                 // which requires it is cleaned up.
2894                 $bodyClasses[] = 'mw-hide-empty-elt';
2895
2896                 $bodyClasses[] = $sk->getPageClasses( $this->getTitle() );
2897                 $bodyClasses[] = 'skin-' . Sanitizer::escapeClass( $sk->getSkinName() );
2898                 $bodyClasses[] =
2899                         'action-' . Sanitizer::escapeClass( Action::getActionName( $this->getContext() ) );
2900
2901                 $bodyAttrs = [];
2902                 // While the implode() is not strictly needed, it's used for backwards compatibility
2903                 // (this used to be built as a string and hooks likely still expect that).
2904                 $bodyAttrs['class'] = implode( ' ', $bodyClasses );
2905
2906                 // Allow skins and extensions to add body attributes they need
2907                 $sk->addToBodyAttributes( $this, $bodyAttrs );
2908                 Hooks::run( 'OutputPageBodyAttributes', [ $this, $sk, &$bodyAttrs ] );
2909
2910                 $pieces[] = Html::openElement( 'body', $bodyAttrs );
2911
2912                 return self::combineWrappedStrings( $pieces );
2913         }
2914
2915         /**
2916          * Get a ResourceLoader object associated with this OutputPage
2917          *
2918          * @return ResourceLoader
2919          */
2920         public function getResourceLoader() {
2921                 if ( is_null( $this->mResourceLoader ) ) {
2922                         $this->mResourceLoader = new ResourceLoader(
2923                                 $this->getConfig(),
2924                                 LoggerFactory::getInstance( 'resourceloader' )
2925                         );
2926                 }
2927                 return $this->mResourceLoader;
2928         }
2929
2930         /**
2931          * Explicily load or embed modules on a page.
2932          *
2933          * @param array|string $modules One or more module names
2934          * @param string $only ResourceLoaderModule TYPE_ class constant
2935          * @param array $extraQuery [optional] Array with extra query parameters for the request
2936          * @return string|WrappedStringList HTML
2937          */
2938         public function makeResourceLoaderLink( $modules, $only, array $extraQuery = [] ) {
2939                 // Apply 'target' and 'origin' filters
2940                 $modules = $this->filterModules( (array)$modules, null, $only );
2941
2942                 return ResourceLoaderClientHtml::makeLoad(
2943                         $this->getRlClientContext(),
2944                         $modules,
2945                         $only,
2946                         $extraQuery
2947                 );
2948         }
2949
2950         /**
2951          * Combine WrappedString chunks and filter out empty ones
2952          *
2953          * @param array $chunks
2954          * @return string|WrappedStringList HTML
2955          */
2956         protected static function combineWrappedStrings( array $chunks ) {
2957                 // Filter out empty values
2958                 $chunks = array_filter( $chunks, 'strlen' );
2959                 return WrappedString::join( "\n", $chunks );
2960         }
2961
2962         private function isUserJsPreview() {
2963                 return $this->getConfig()->get( 'AllowUserJs' )
2964                         && $this->getTitle()
2965                         && $this->getTitle()->isUserJsConfigPage()
2966                         && $this->userCanPreview();
2967         }
2968
2969         protected function isUserCssPreview() {
2970                 return $this->getConfig()->get( 'AllowUserCss' )
2971                         && $this->getTitle()
2972                         && $this->getTitle()->isUserCssConfigPage()
2973                         && $this->userCanPreview();
2974         }
2975
2976         /**
2977          * JS stuff to put at the bottom of the `<body>`.
2978          * These are legacy scripts ($this->mScripts), and user JS.
2979          *
2980          * @return string|WrappedStringList HTML
2981          */
2982         public function getBottomScripts() {
2983                 $chunks = [];
2984                 $chunks[] = $this->getRlClient()->getBodyHtml();
2985
2986                 // Legacy non-ResourceLoader scripts
2987                 $chunks[] = $this->mScripts;
2988
2989                 // Exempt 'user' module
2990                 // - May need excludepages for live preview. (T28283)
2991                 // - Must use TYPE_COMBINED so its response is handled by mw.loader.implement() which
2992                 //   ensures execution is scheduled after the "site" module.
2993                 // - Don't load if module state is already resolved as "ready".
2994                 if ( $this->rlUserModuleState === 'loading' ) {
2995                         if ( $this->isUserJsPreview() ) {
2996                                 $chunks[] = $this->makeResourceLoaderLink( 'user', ResourceLoaderModule::TYPE_COMBINED,
2997                                         [ 'excludepage' => $this->getTitle()->getPrefixedDBkey() ]
2998                                 );
2999                                 $chunks[] = ResourceLoader::makeInlineScript(
3000                                         Xml::encodeJsCall( 'mw.loader.using', [
3001                                                 [ 'user', 'site' ],
3002                                                 new XmlJsCode(
3003                                                         'function () {'
3004                                                                 . Xml::encodeJsCall( '$.globalEval', [
3005                                                                         $this->getRequest()->getText( 'wpTextbox1' )
3006                                                                 ] )
3007                                                                 . '}'
3008                                                 )
3009                                         ] )
3010                                 );
3011                                 // FIXME: If the user is previewing, say, ./vector.js, his ./common.js will be loaded
3012                                 // asynchronously and may arrive *after* the inline script here. So the previewed code
3013                                 // may execute before ./common.js runs. Normally, ./common.js runs before ./vector.js.
3014                                 // Similarly, when previewing ./common.js and the user module does arrive first,
3015                                 // it will arrive without common.js and the inline script runs after.
3016                                 // Thus running common after the excluded subpage.
3017                         } else {
3018                                 // Load normally
3019                                 $chunks[] = $this->makeResourceLoaderLink( 'user', ResourceLoaderModule::TYPE_COMBINED );
3020                         }
3021                 }
3022
3023                 if ( $this->limitReportJSData ) {
3024                         $chunks[] = ResourceLoader::makeInlineScript(
3025                                 ResourceLoader::makeConfigSetScript(
3026                                         [ 'wgPageParseReport' => $this->limitReportJSData ]
3027                                 )
3028                         );
3029                 }
3030
3031                 return self::combineWrappedStrings( $chunks );
3032         }
3033
3034         /**
3035          * Get the javascript config vars to include on this page
3036          *
3037          * @return array Array of javascript config vars
3038          * @since 1.23
3039          */
3040         public function getJsConfigVars() {
3041                 return $this->mJsConfigVars;
3042         }
3043
3044         /**
3045          * Add one or more variables to be set in mw.config in JavaScript
3046          *
3047          * @param string|array $keys Key or array of key/value pairs
3048          * @param mixed $value [optional] Value of the configuration variable
3049          */
3050         public function addJsConfigVars( $keys, $value = null ) {
3051                 if ( is_array( $keys ) ) {
3052                         foreach ( $keys as $key => $value ) {
3053                                 $this->mJsConfigVars[$key] = $value;
3054                         }
3055                         return;
3056                 }
3057
3058                 $this->mJsConfigVars[$keys] = $value;
3059         }
3060
3061         /**
3062          * Get an array containing the variables to be set in mw.config in JavaScript.
3063          *
3064          * Do not add things here which can be evaluated in ResourceLoaderStartUpModule
3065          * - in other words, page-independent/site-wide variables (without state).
3066          * You will only be adding bloat to the html page and causing page caches to
3067          * have to be purged on configuration changes.
3068          * @return array
3069          */
3070         public function getJSVars() {
3071                 global $wgContLang;
3072
3073                 $curRevisionId = 0;
3074                 $articleId = 0;
3075                 $canonicalSpecialPageName = false; # T23115
3076
3077                 $title = $this->getTitle();
3078                 $ns = $title->getNamespace();
3079                 $canonicalNamespace = MWNamespace::exists( $ns )
3080                         ? MWNamespace::getCanonicalName( $ns )
3081                         : $title->getNsText();
3082
3083                 $sk = $this->getSkin();
3084                 // Get the relevant title so that AJAX features can use the correct page name
3085                 // when making API requests from certain special pages (T36972).
3086                 $relevantTitle = $sk->getRelevantTitle();
3087                 $relevantUser = $sk->getRelevantUser();
3088
3089                 if ( $ns == NS_SPECIAL ) {
3090                         list( $canonicalSpecialPageName, /*...*/ ) =
3091                                 SpecialPageFactory::resolveAlias( $title->getDBkey() );
3092                 } elseif ( $this->canUseWikiPage() ) {
3093                         $wikiPage = $this->getWikiPage();
3094                         $curRevisionId = $wikiPage->getLatest();
3095                         $articleId = $wikiPage->getId();
3096                 }
3097
3098                 $lang = $title->getPageViewLanguage();
3099
3100                 // Pre-process information
3101                 $separatorTransTable = $lang->separatorTransformTable();
3102                 $separatorTransTable = $separatorTransTable ? $separatorTransTable : [];
3103                 $compactSeparatorTransTable = [
3104                         implode( "\t", array_keys( $separatorTransTable ) ),
3105                         implode( "\t", $separatorTransTable ),
3106                 ];
3107                 $digitTransTable = $lang->digitTransformTable();
3108                 $digitTransTable = $digitTransTable ? $digitTransTable : [];
3109                 $compactDigitTransTable = [
3110                         implode( "\t", array_keys( $digitTransTable ) ),
3111                         implode( "\t", $digitTransTable ),
3112                 ];
3113
3114                 $user = $this->getUser();
3115
3116                 $vars = [
3117                         'wgCanonicalNamespace' => $canonicalNamespace,
3118                         'wgCanonicalSpecialPageName' => $canonicalSpecialPageName,
3119                         'wgNamespaceNumber' => $title->getNamespace(),
3120                         'wgPageName' => $title->getPrefixedDBkey(),
3121                         'wgTitle' => $title->getText(),
3122                         'wgCurRevisionId' => $curRevisionId,
3123                         'wgRevisionId' => (int)$this->getRevisionId(),
3124                         'wgArticleId' => $articleId,
3125                         'wgIsArticle' => $this->isArticle(),
3126                         'wgIsRedirect' => $title->isRedirect(),
3127                         'wgAction' => Action::getActionName( $this->getContext() ),
3128                         'wgUserName' => $user->isAnon() ? null : $user->getName(),
3129                         'wgUserGroups' => $user->getEffectiveGroups(),
3130                         'wgCategories' => $this->getCategories(),
3131                         'wgBreakFrames' => $this->getFrameOptions() == 'DENY',
3132                         'wgPageContentLanguage' => $lang->getCode(),
3133                         'wgPageContentModel' => $title->getContentModel(),
3134                         'wgSeparatorTransformTable' => $compactSeparatorTransTable,
3135                         'wgDigitTransformTable' => $compactDigitTransTable,
3136                         'wgDefaultDateFormat' => $lang->getDefaultDateFormat(),
3137                         'wgMonthNames' => $lang->getMonthNamesArray(),
3138                         'wgMonthNamesShort' => $lang->getMonthAbbreviationsArray(),
3139                         'wgRelevantPageName' => $relevantTitle->getPrefixedDBkey(),
3140                         'wgRelevantArticleId' => $relevantTitle->getArticleID(),
3141                         'wgRequestId' => WebRequest::getRequestId(),
3142                 ];
3143
3144                 if ( $user->isLoggedIn() ) {
3145                         $vars['wgUserId'] = $user->getId();
3146                         $vars['wgUserEditCount'] = $user->getEditCount();
3147                         $userReg = $user->getRegistration();
3148                         $vars['wgUserRegistration'] = $userReg ? wfTimestamp( TS_UNIX, $userReg ) * 1000 : null;
3149                         // Get the revision ID of the oldest new message on the user's talk
3150                         // page. This can be used for constructing new message alerts on
3151                         // the client side.
3152                         $vars['wgUserNewMsgRevisionId'] = $user->getNewMessageRevisionId();
3153                 }
3154
3155                 if ( $wgContLang->hasVariants() ) {
3156                         $vars['wgUserVariant'] = $wgContLang->getPreferredVariant();
3157                 }
3158                 // Same test as SkinTemplate
3159                 $vars['wgIsProbablyEditable'] = $title->quickUserCan( 'edit', $user )
3160                         && ( $title->exists() || $title->quickUserCan( 'create', $user ) );
3161
3162                 $vars['wgRelevantPageIsProbablyEditable'] = $relevantTitle
3163                         && $relevantTitle->quickUserCan( 'edit', $user )
3164                         && ( $relevantTitle->exists() || $relevantTitle->quickUserCan( 'create', $user ) );
3165
3166                 foreach ( $title->getRestrictionTypes() as $type ) {
3167                         // Following keys are set in $vars:
3168                         // wgRestrictionCreate, wgRestrictionEdit, wgRestrictionMove, wgRestrictionUpload
3169                         $vars['wgRestriction' . ucfirst( $type )] = $title->getRestrictions( $type );
3170                 }
3171
3172                 if ( $title->isMainPage() ) {
3173                         $vars['wgIsMainPage'] = true;
3174                 }
3175
3176                 if ( $this->mRedirectedFrom ) {
3177                         $vars['wgRedirectedFrom'] = $this->mRedirectedFrom->getPrefixedDBkey();
3178                 }
3179
3180                 if ( $relevantUser ) {
3181                         $vars['wgRelevantUserName'] = $relevantUser->getName();
3182                 }
3183
3184                 // Allow extensions to add their custom variables to the mw.config map.
3185                 // Use the 'ResourceLoaderGetConfigVars' hook if the variable is not
3186                 // page-dependant but site-wide (without state).
3187                 // Alternatively, you may want to use OutputPage->addJsConfigVars() instead.
3188                 Hooks::run( 'MakeGlobalVariablesScript', [ &$vars, $this ] );
3189
3190                 // Merge in variables from addJsConfigVars last
3191                 return array_merge( $vars, $this->getJsConfigVars() );
3192         }
3193
3194         /**
3195          * To make it harder for someone to slip a user a fake
3196          * user-JavaScript or user-CSS preview, a random token
3197          * is associated with the login session. If it's not
3198          * passed back with the preview request, we won't render
3199          * the code.
3200          *
3201          * @return bool
3202          */
3203         public function userCanPreview() {
3204                 $request = $this->getRequest();
3205                 if (
3206                         $request->getVal( 'action' ) !== 'submit' ||
3207                         !$request->getCheck( 'wpPreview' ) ||
3208                         !$request->wasPosted()
3209                 ) {
3210                         return false;
3211                 }
3212
3213                 $user = $this->getUser();
3214
3215                 if ( !$user->isLoggedIn() ) {
3216                         // Anons have predictable edit tokens
3217                         return false;
3218                 }
3219                 if ( !$user->matchEditToken( $request->getVal( 'wpEditToken' ) ) ) {
3220                         return false;
3221                 }
3222
3223                 $title = $this->getTitle();
3224                 if (
3225                         !$title->isUserJsConfigPage()
3226                         && !$title->isUserCssConfigPage()
3227                 ) {
3228                         return false;
3229                 }
3230                 if ( !$title->isSubpageOf( $user->getUserPage() ) ) {
3231                         // Don't execute another user's CSS or JS on preview (T85855)
3232                         return false;
3233                 }
3234
3235                 $errors = $title->getUserPermissionsErrors( 'edit', $user );
3236                 if ( count( $errors ) !== 0 ) {
3237                         return false;
3238                 }
3239
3240                 return true;
3241         }
3242
3243         /**
3244          * @return array Array in format "link name or number => 'link html'".
3245          */
3246         public function getHeadLinksArray() {
3247                 global $wgVersion;
3248
3249                 $tags = [];
3250                 $config = $this->getConfig();
3251
3252                 $canonicalUrl = $this->mCanonicalUrl;
3253
3254                 $tags['meta-generator'] = Html::element( 'meta', [
3255                         'name' => 'generator',
3256                         'content' => "MediaWiki $wgVersion",
3257                 ] );
3258
3259                 if ( $config->get( 'ReferrerPolicy' ) !== false ) {
3260                         // Per https://w3c.github.io/webappsec-referrer-policy/#unknown-policy-values
3261                         // fallbacks should come before the primary value so we need to reverse the array.
3262                         foreach ( array_reverse( (array)$config->get( 'ReferrerPolicy' ) ) as $i => $policy ) {
3263                                 $tags["meta-referrer-$i"] = Html::element( 'meta', [
3264                                         'name' => 'referrer',
3265                                         'content' => $policy,
3266                                 ] );
3267                         }
3268                 }
3269
3270                 $p = "{$this->mIndexPolicy},{$this->mFollowPolicy}";
3271                 if ( $p !== 'index,follow' ) {
3272                         // http://www.robotstxt.org/wc/meta-user.html
3273                         // Only show if it's different from the default robots policy
3274                         $tags['meta-robots'] = Html::element( 'meta', [
3275                                 'name' => 'robots',
3276                                 'content' => $p,
3277                         ] );
3278                 }
3279
3280                 foreach ( $this->mMetatags as $tag ) {
3281                         if ( strncasecmp( $tag[0], 'http:', 5 ) === 0 ) {
3282                                 $a = 'http-equiv';
3283                                 $tag[0] = substr( $tag[0], 5 );
3284                         } elseif ( strncasecmp( $tag[0], 'og:', 3 ) === 0 ) {
3285                                 $a = 'property';
3286                         } else {
3287                                 $a = 'name';
3288                         }
3289                         $tagName = "meta-{$tag[0]}";
3290                         if ( isset( $tags[$tagName] ) ) {
3291                                 $tagName .= $tag[1];
3292                         }
3293                         $tags[$tagName] = Html::element( 'meta',
3294                                 [
3295                                         $a => $tag[0],
3296                                         'content' => $tag[1]
3297                                 ]
3298                         );
3299                 }
3300
3301                 foreach ( $this->mLinktags as $tag ) {
3302                         $tags[] = Html::element( 'link', $tag );
3303                 }
3304
3305                 # Universal edit button
3306                 if ( $config->get( 'UniversalEditButton' ) && $this->isArticleRelated() ) {
3307                         $user = $this->getUser();
3308                         if ( $this->getTitle()->quickUserCan( 'edit', $user )
3309                                 && ( $this->getTitle()->exists() ||
3310                                         $this->getTitle()->quickUserCan( 'create', $user ) )
3311                         ) {
3312                                 // Original UniversalEditButton
3313                                 $msg = $this->msg( 'edit' )->text();
3314                                 $tags['universal-edit-button'] = Html::element( 'link', [
3315                                         'rel' => 'alternate',
3316                                         'type' => 'application/x-wiki',
3317                                         'title' => $msg,
3318                                         'href' => $this->getTitle()->getEditURL(),
3319                                 ] );
3320                                 // Alternate edit link
3321                                 $tags['alternative-edit'] = Html::element( 'link', [
3322                                         'rel' => 'edit',
3323                                         'title' => $msg,
3324                                         'href' => $this->getTitle()->getEditURL(),
3325                                 ] );
3326                         }
3327                 }
3328
3329                 # Generally the order of the favicon and apple-touch-icon links
3330                 # should not matter, but Konqueror (3.5.9 at least) incorrectly
3331                 # uses whichever one appears later in the HTML source. Make sure
3332                 # apple-touch-icon is specified first to avoid this.
3333                 if ( $config->get( 'AppleTouchIcon' ) !== false ) {
3334                         $tags['apple-touch-icon'] = Html::element( 'link', [
3335                                 'rel' => 'apple-touch-icon',
3336                                 'href' => $config->get( 'AppleTouchIcon' )
3337                         ] );
3338                 }
3339
3340                 if ( $config->get( 'Favicon' ) !== false ) {
3341                         $tags['favicon'] = Html::element( 'link', [
3342                                 'rel' => 'shortcut icon',
3343                                 'href' => $config->get( 'Favicon' )
3344                         ] );
3345                 }
3346
3347                 # OpenSearch description link
3348                 $tags['opensearch'] = Html::element( 'link', [
3349                         'rel' => 'search',
3350                         'type' => 'application/opensearchdescription+xml',
3351                         'href' => wfScript( 'opensearch_desc' ),
3352                         'title' => $this->msg( 'opensearch-desc' )->inContentLanguage()->text(),
3353                 ] );
3354
3355                 # Real Simple Discovery link, provides auto-discovery information
3356                 # for the MediaWiki API (and potentially additional custom API
3357                 # support such as WordPress or Twitter-compatible APIs for a
3358                 # blogging extension, etc)
3359                 $tags['rsd'] = Html::element( 'link', [
3360                         'rel' => 'EditURI',
3361                         'type' => 'application/rsd+xml',
3362                         // Output a protocol-relative URL here if $wgServer is protocol-relative.
3363                         // Whether RSD accepts relative or protocol-relative URLs is completely
3364                         // undocumented, though.
3365                         'href' => wfExpandUrl( wfAppendQuery(
3366                                 wfScript( 'api' ),
3367                                 [ 'action' => 'rsd' ] ),
3368                                 PROTO_RELATIVE
3369                         ),
3370                 ] );
3371
3372                 # Language variants
3373                 if ( !$config->get( 'DisableLangConversion' ) ) {
3374                         $lang = $this->getTitle()->getPageLanguage();
3375                         if ( $lang->hasVariants() ) {
3376                                 $variants = $lang->getVariants();
3377                                 foreach ( $variants as $variant ) {
3378                                         $tags["variant-$variant"] = Html::element( 'link', [
3379                                                 'rel' => 'alternate',
3380                                                 'hreflang' => LanguageCode::bcp47( $variant ),
3381                                                 'href' => $this->getTitle()->getLocalURL(
3382                                                         [ 'variant' => $variant ] )
3383                                                 ]
3384                                         );
3385                                 }
3386                                 # x-default link per https://support.google.com/webmasters/answer/189077?hl=en
3387                                 $tags["variant-x-default"] = Html::element( 'link', [
3388                                         'rel' => 'alternate',
3389                                         'hreflang' => 'x-default',
3390                                         'href' => $this->getTitle()->getLocalURL() ] );
3391                         }
3392                 }
3393
3394                 # Copyright
3395                 if ( $this->copyrightUrl !== null ) {
3396                         $copyright = $this->copyrightUrl;
3397                 } else {
3398                         $copyright = '';
3399                         if ( $config->get( 'RightsPage' ) ) {
3400                                 $copy = Title::newFromText( $config->get( 'RightsPage' ) );
3401
3402                                 if ( $copy ) {
3403                                         $copyright = $copy->getLocalURL();
3404                                 }
3405                         }
3406
3407                         if ( !$copyright && $config->get( 'RightsUrl' ) ) {
3408                                 $copyright = $config->get( 'RightsUrl' );
3409                         }
3410                 }
3411
3412                 if ( $copyright ) {
3413                         $tags['copyright'] = Html::element( 'link', [
3414                                 'rel' => 'license',
3415                                 'href' => $copyright ]
3416                         );
3417                 }
3418
3419                 # Feeds
3420                 if ( $config->get( 'Feed' ) ) {
3421                         $feedLinks = [];
3422
3423                         foreach ( $this->getSyndicationLinks() as $format => $link ) {
3424                                 # Use the page name for the title.  In principle, this could
3425                                 # lead to issues with having the same name for different feeds
3426                                 # corresponding to the same page, but we can't avoid that at
3427                                 # this low a level.
3428
3429                                 $feedLinks[] = $this->feedLink(
3430                                         $format,
3431                                         $link,
3432                                         # Used messages: 'page-rss-feed' and 'page-atom-feed' (for an easier grep)
3433                                         $this->msg(
3434                                                 "page-{$format}-feed", $this->getTitle()->getPrefixedText()
3435                                         )->text()
3436                                 );
3437                         }
3438
3439                         # Recent changes feed should appear on every page (except recentchanges,
3440                         # that would be redundant). Put it after the per-page feed to avoid
3441                         # changing existing behavior. It's still available, probably via a
3442                         # menu in your browser. Some sites might have a different feed they'd
3443                         # like to promote instead of the RC feed (maybe like a "Recent New Articles"
3444                         # or "Breaking news" one). For this, we see if $wgOverrideSiteFeed is defined.
3445                         # If so, use it instead.
3446                         $sitename = $config->get( 'Sitename' );
3447                         if ( $config->get( 'OverrideSiteFeed' ) ) {
3448                                 foreach ( $config->get( 'OverrideSiteFeed' ) as $type => $feedUrl ) {
3449                                         // Note, this->feedLink escapes the url.
3450                                         $feedLinks[] = $this->feedLink(
3451                                                 $type,
3452                                                 $feedUrl,
3453                                                 $this->msg( "site-{$type}-feed", $sitename )->text()
3454                                         );
3455                                 }
3456                         } elseif ( !$this->getTitle()->isSpecial( 'Recentchanges' ) ) {
3457                                 $rctitle = SpecialPage::getTitleFor( 'Recentchanges' );
3458                                 foreach ( $config->get( 'AdvertisedFeedTypes' ) as $format ) {
3459                                         $feedLinks[] = $this->feedLink(
3460                                                 $format,
3461                                                 $rctitle->getLocalURL( [ 'feed' => $format ] ),
3462                                                 # For grep: 'site-rss-feed', 'site-atom-feed'
3463                                                 $this->msg( "site-{$format}-feed", $sitename )->text()
3464                                         );
3465                                 }
3466                         }
3467
3468                         # Allow extensions to change the list pf feeds. This hook is primarily for changing,
3469                         # manipulating or removing existing feed tags. If you want to add new feeds, you should
3470                         # use OutputPage::addFeedLink() instead.
3471                         Hooks::run( 'AfterBuildFeedLinks', [ &$feedLinks ] );
3472
3473                         $tags += $feedLinks;
3474                 }
3475
3476                 # Canonical URL
3477                 if ( $config->get( 'EnableCanonicalServerLink' ) ) {
3478                         if ( $canonicalUrl !== false ) {
3479                                 $canonicalUrl = wfExpandUrl( $canonicalUrl, PROTO_CANONICAL );
3480                         } else {
3481                                 if ( $this->isArticleRelated() ) {
3482                                         // This affects all requests where "setArticleRelated" is true. This is
3483                                         // typically all requests that show content (query title, curid, oldid, diff),
3484                                         // and all wikipage actions (edit, delete, purge, info, history etc.).
3485                                         // It does not apply to File pages and Special pages.
3486                                         // 'history' and 'info' actions address page metadata rather than the page
3487                                         // content itself, so they may not be canonicalized to the view page url.
3488                                         // TODO: this ought to be better encapsulated in the Action class.
3489                                         $action = Action::getActionName( $this->getContext() );
3490                                         if ( in_array( $action, [ 'history', 'info' ] ) ) {
3491                                                 $query = "action={$action}";
3492                                         } else {
3493                                                 $query = '';
3494                                         }
3495                                         $canonicalUrl = $this->getTitle()->getCanonicalURL( $query );
3496                                 } else {
3497                                         $reqUrl = $this->getRequest()->getRequestURL();
3498                                         $canonicalUrl = wfExpandUrl( $reqUrl, PROTO_CANONICAL );
3499                                 }
3500                         }
3501                 }
3502                 if ( $canonicalUrl !== false ) {
3503                         $tags[] = Html::element( 'link', [
3504                                 'rel' => 'canonical',
3505                                 'href' => $canonicalUrl
3506                         ] );
3507                 }
3508
3509                 return $tags;
3510         }
3511
3512         /**
3513          * Generate a "<link rel/>" for a feed.
3514          *
3515          * @param string $type Feed type
3516          * @param string $url URL to the feed
3517          * @param string $text Value of the "title" attribute
3518          * @return string HTML fragment
3519          */
3520         private function feedLink( $type, $url, $text ) {
3521                 return Html::element( 'link', [
3522                         'rel' => 'alternate',
3523                         'type' => "application/$type+xml",
3524                         'title' => $text,
3525                         'href' => $url ]
3526                 );
3527         }
3528
3529         /**
3530          * Add a local or specified stylesheet, with the given media options.
3531          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3532          *
3533          * @param string $style URL to the file
3534          * @param string $media To specify a media type, 'screen', 'printable', 'handheld' or any.
3535          * @param string $condition For IE conditional comments, specifying an IE version
3536          * @param string $dir Set to 'rtl' or 'ltr' for direction-specific sheets
3537          */
3538         public function addStyle( $style, $media = '', $condition = '', $dir = '' ) {
3539                 $options = [];
3540                 if ( $media ) {
3541                         $options['media'] = $media;
3542                 }
3543                 if ( $condition ) {
3544                         $options['condition'] = $condition;
3545                 }
3546                 if ( $dir ) {
3547                         $options['dir'] = $dir;
3548                 }
3549                 $this->styles[$style] = $options;
3550         }
3551
3552         /**
3553          * Adds inline CSS styles
3554          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3555          *
3556          * @param mixed $style_css Inline CSS
3557          * @param string $flip Set to 'flip' to flip the CSS if needed
3558          */
3559         public function addInlineStyle( $style_css, $flip = 'noflip' ) {
3560                 if ( $flip === 'flip' && $this->getLanguage()->isRTL() ) {
3561                         # If wanted, and the interface is right-to-left, flip the CSS
3562                         $style_css = CSSJanus::transform( $style_css, true, false );
3563                 }
3564                 $this->mInlineStyles .= Html::inlineStyle( $style_css );
3565         }
3566
3567         /**
3568          * Build exempt modules and legacy non-ResourceLoader styles.
3569          *
3570          * @return string|WrappedStringList HTML
3571          */
3572         protected function buildExemptModules() {
3573                 global $wgContLang;
3574
3575                 $chunks = [];
3576                 // Things that go after the ResourceLoaderDynamicStyles marker
3577                 $append = [];
3578
3579                 // Exempt 'user' styles module (may need 'excludepages' for live preview)
3580                 if ( $this->isUserCssPreview() ) {
3581                         $append[] = $this->makeResourceLoaderLink(
3582                                 'user.styles',
3583                                 ResourceLoaderModule::TYPE_STYLES,
3584                                 [ 'excludepage' => $this->getTitle()->getPrefixedDBkey() ]
3585                         );
3586
3587                         // Load the previewed CSS. Janus it if needed.
3588                         // User-supplied CSS is assumed to in the wiki's content language.
3589                         $previewedCSS = $this->getRequest()->getText( 'wpTextbox1' );
3590                         if ( $this->getLanguage()->getDir() !== $wgContLang->getDir() ) {
3591                                 $previewedCSS = CSSJanus::transform( $previewedCSS, true, false );
3592                         }
3593                         $append[] = Html::inlineStyle( $previewedCSS );
3594                 }
3595
3596                 // We want site, private and user styles to override dynamically added styles from
3597                 // general modules, but we want dynamically added styles to override statically added
3598                 // style modules. So the order has to be:
3599                 // - page style modules (formatted by ResourceLoaderClientHtml::getHeadHtml())
3600                 // - dynamically loaded styles (added by mw.loader before ResourceLoaderDynamicStyles)
3601                 // - ResourceLoaderDynamicStyles marker
3602                 // - site/private/user styles
3603
3604                 // Add legacy styles added through addStyle()/addInlineStyle() here
3605                 $chunks[] = implode( '', $this->buildCssLinksArray() ) . $this->mInlineStyles;
3606
3607                 $chunks[] = Html::element(
3608                         'meta',
3609                         [ 'name' => 'ResourceLoaderDynamicStyles', 'content' => '' ]
3610                 );
3611
3612                 $separateReq = [ 'site.styles', 'user.styles' ];
3613                 foreach ( $this->rlExemptStyleModules as $group => $moduleNames ) {
3614                         // Combinable modules
3615                         $chunks[] = $this->makeResourceLoaderLink(
3616                                 array_diff( $moduleNames, $separateReq ),
3617                                 ResourceLoaderModule::TYPE_STYLES
3618                         );
3619
3620                         foreach ( array_intersect( $moduleNames, $separateReq ) as $name ) {
3621                                 // These require their own dedicated request in order to support "@import"
3622                                 // syntax, which is incompatible with concatenation. (T147667, T37562)
3623                                 $chunks[] = $this->makeResourceLoaderLink( $name,
3624                                         ResourceLoaderModule::TYPE_STYLES
3625                                 );
3626                         }
3627                 }
3628
3629                 return self::combineWrappedStrings( array_merge( $chunks, $append ) );
3630         }
3631
3632         /**
3633          * @return array
3634          */
3635         public function buildCssLinksArray() {
3636                 $links = [];
3637
3638                 foreach ( $this->styles as $file => $options ) {
3639                         $link = $this->styleLink( $file, $options );
3640                         if ( $link ) {
3641                                 $links[$file] = $link;
3642                         }
3643                 }
3644                 return $links;
3645         }
3646
3647         /**
3648          * Generate \<link\> tags for stylesheets
3649          *
3650          * @param string $style URL to the file
3651          * @param array $options Option, can contain 'condition', 'dir', 'media' keys
3652          * @return string HTML fragment
3653          */
3654         protected function styleLink( $style, array $options ) {
3655                 if ( isset( $options['dir'] ) ) {
3656                         if ( $this->getLanguage()->getDir() != $options['dir'] ) {
3657                                 return '';
3658                         }
3659                 }
3660
3661                 if ( isset( $options['media'] ) ) {
3662                         $media = self::transformCssMedia( $options['media'] );
3663                         if ( is_null( $media ) ) {
3664                                 return '';
3665                         }
3666                 } else {
3667                         $media = 'all';
3668                 }
3669
3670                 if ( substr( $style, 0, 1 ) == '/' ||
3671                         substr( $style, 0, 5 ) == 'http:' ||
3672                         substr( $style, 0, 6 ) == 'https:' ) {
3673                         $url = $style;
3674                 } else {
3675                         $config = $this->getConfig();
3676                         $url = $config->get( 'StylePath' ) . '/' . $style . '?' .
3677                                 $config->get( 'StyleVersion' );
3678                 }
3679
3680                 $link = Html::linkedStyle( $url, $media );
3681
3682                 if ( isset( $options['condition'] ) ) {
3683                         $condition = htmlspecialchars( $options['condition'] );
3684                         $link = "<!--[if $condition]>$link<![endif]-->";
3685                 }
3686                 return $link;
3687         }
3688
3689         /**
3690          * Transform path to web-accessible static resource.
3691          *
3692          * This is used to add a validation hash as query string.
3693          * This aids various behaviors:
3694          *
3695          * - Put long Cache-Control max-age headers on responses for improved
3696          *   cache performance.
3697          * - Get the correct version of a file as expected by the current page.
3698          * - Instantly get the updated version of a file after deployment.
3699          *
3700          * Avoid using this for urls included in HTML as otherwise clients may get different
3701          * versions of a resource when navigating the site depending on when the page was cached.
3702          * If changes to the url propagate, this is not a problem (e.g. if the url is in
3703          * an external stylesheet).
3704          *
3705          * @since 1.27
3706          * @param Config $config
3707          * @param string $path Path-absolute URL to file (from document root, must start with "/")
3708          * @return string URL
3709          */
3710         public static function transformResourcePath( Config $config, $path ) {
3711                 global $IP;
3712
3713                 $localDir = $IP;
3714                 $remotePathPrefix = $config->get( 'ResourceBasePath' );
3715                 if ( $remotePathPrefix === '' ) {
3716                         // The configured base path is required to be empty string for
3717                         // wikis in the domain root
3718                         $remotePath = '/';
3719                 } else {
3720                         $remotePath = $remotePathPrefix;
3721                 }
3722                 if ( strpos( $path, $remotePath ) !== 0 || substr( $path, 0, 2 ) === '//' ) {
3723                         // - Path is outside wgResourceBasePath, ignore.
3724                         // - Path is protocol-relative. Fixes T155310. Not supported by RelPath lib.
3725                         return $path;
3726                 }
3727                 // For files in resources, extensions/ or skins/, ResourceBasePath is preferred here.
3728                 // For other misc files in $IP, we'll fallback to that as well. There is, however, a fourth
3729                 // supported dir/path pair in the configuration (wgUploadDirectory, wgUploadPath)
3730                 // which is not expected to be in wgResourceBasePath on CDNs. (T155146)
3731                 $uploadPath = $config->get( 'UploadPath' );
3732                 if ( strpos( $path, $uploadPath ) === 0 ) {
3733                         $localDir = $config->get( 'UploadDirectory' );
3734                         $remotePathPrefix = $remotePath = $uploadPath;
3735                 }
3736
3737                 $path = RelPath::getRelativePath( $path, $remotePath );
3738                 return self::transformFilePath( $remotePathPrefix, $localDir, $path );
3739         }
3740
3741         /**
3742          * Utility method for transformResourceFilePath().
3743          *
3744          * Caller is responsible for ensuring the file exists. Emits a PHP warning otherwise.
3745          *
3746          * @since 1.27
3747          * @param string $remotePathPrefix URL path prefix that points to $localPath
3748          * @param string $localPath File directory exposed at $remotePath
3749          * @param string $file Path to target file relative to $localPath
3750          * @return string URL
3751          */
3752         public static function transformFilePath( $remotePathPrefix, $localPath, $file ) {
3753                 $hash = md5_file( "$localPath/$file" );
3754                 if ( $hash === false ) {
3755                         wfLogWarning( __METHOD__ . ": Failed to hash $localPath/$file" );
3756                         $hash = '';
3757                 }
3758                 return "$remotePathPrefix/$file?" . substr( $hash, 0, 5 );
3759         }
3760
3761         /**
3762          * Transform "media" attribute based on request parameters
3763          *
3764          * @param string $media Current value of the "media" attribute
3765          * @return string Modified value of the "media" attribute, or null to skip
3766          * this stylesheet
3767          */
3768         public static function transformCssMedia( $media ) {
3769                 global $wgRequest;
3770
3771                 // https://www.w3.org/TR/css3-mediaqueries/#syntax
3772                 $screenMediaQueryRegex = '/^(?:only\s+)?screen\b/i';
3773
3774                 // Switch in on-screen display for media testing
3775                 $switches = [
3776                         'printable' => 'print',
3777                         'handheld' => 'handheld',
3778                 ];
3779                 foreach ( $switches as $switch => $targetMedia ) {
3780                         if ( $wgRequest->getBool( $switch ) ) {
3781                                 if ( $media == $targetMedia ) {
3782                                         $media = '';
3783                                 } elseif ( preg_match( $screenMediaQueryRegex, $media ) === 1 ) {
3784                                         /* This regex will not attempt to understand a comma-separated media_query_list
3785                                          *
3786                                          * Example supported values for $media:
3787                                          * 'screen', 'only screen', 'screen and (min-width: 982px)' ),
3788                                          * Example NOT supported value for $media:
3789                                          * '3d-glasses, screen, print and resolution > 90dpi'
3790                                          *
3791                                          * If it's a print request, we never want any kind of screen stylesheets
3792                                          * If it's a handheld request (currently the only other choice with a switch),
3793                                          * we don't want simple 'screen' but we might want screen queries that
3794                                          * have a max-width or something, so we'll pass all others on and let the
3795                                          * client do the query.
3796                                          */
3797                                         if ( $targetMedia == 'print' || $media == 'screen' ) {
3798                                                 return null;
3799                                         }
3800                                 }
3801                         }
3802                 }
3803
3804                 return $media;
3805         }
3806
3807         /**
3808          * Add a wikitext-formatted message to the output.
3809          * This is equivalent to:
3810          *
3811          *    $wgOut->addWikiText( wfMessage( ... )->plain() )
3812          */
3813         public function addWikiMsg( /*...*/ ) {
3814                 $args = func_get_args();
3815                 $name = array_shift( $args );
3816                 $this->addWikiMsgArray( $name, $args );
3817         }
3818
3819         /**
3820          * Add a wikitext-formatted message to the output.
3821          * Like addWikiMsg() except the parameters are taken as an array
3822          * instead of a variable argument list.
3823          *
3824          * @param string $name
3825          * @param array $args
3826          */
3827         public function addWikiMsgArray( $name, $args ) {
3828                 $this->addHTML( $this->msg( $name, $args )->parseAsBlock() );
3829         }
3830
3831         /**
3832          * This function takes a number of message/argument specifications, wraps them in
3833          * some overall structure, and then parses the result and adds it to the output.
3834          *
3835          * In the $wrap, $1 is replaced with the first message, $2 with the second,
3836          * and so on. The subsequent arguments may be either
3837          * 1) strings, in which case they are message names, or
3838          * 2) arrays, in which case, within each array, the first element is the message
3839          *    name, and subsequent elements are the parameters to that message.
3840          *
3841          * Don't use this for messages that are not in the user's interface language.
3842          *
3843          * For example:
3844          *
3845          *    $wgOut->wrapWikiMsg( "<div class='error'>\n$1\n</div>", 'some-error' );
3846          *
3847          * Is equivalent to:
3848          *
3849          *    $wgOut->addWikiText( "<div class='error'>\n"
3850          *        . wfMessage( 'some-error' )->plain() . "\n</div>" );
3851          *
3852          * The newline after the opening div is needed in some wikitext. See T21226.
3853          *
3854          * @param string $wrap
3855          */
3856         public function wrapWikiMsg( $wrap /*, ...*/ ) {
3857                 $msgSpecs = func_get_args();
3858                 array_shift( $msgSpecs );
3859                 $msgSpecs = array_values( $msgSpecs );
3860                 $s = $wrap;
3861                 foreach ( $msgSpecs as $n => $spec ) {
3862                         if ( is_array( $spec ) ) {
3863                                 $args = $spec;
3864                                 $name = array_shift( $args );
3865                                 if ( isset( $args['options'] ) ) {
3866                                         unset( $args['options'] );
3867                                         wfDeprecated(
3868                                                 'Adding "options" to ' . __METHOD__ . ' is no longer supported',
3869                                                 '1.20'
3870                                         );
3871                                 }
3872                         } else {
3873                                 $args = [];
3874                                 $name = $spec;
3875                         }
3876                         $s = str_replace( '$' . ( $n + 1 ), $this->msg( $name, $args )->plain(), $s );
3877                 }
3878                 $this->addWikiText( $s );
3879         }
3880
3881         /**
3882          * Whether the output has a table of contents
3883          * @return bool
3884          * @since 1.22
3885          */
3886         public function isTOCEnabled() {
3887                 return $this->mEnableTOC;
3888         }
3889
3890         /**
3891          * Enables/disables section edit links, doesn't override __NOEDITSECTION__
3892          * @param bool $flag
3893          * @since 1.23
3894          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
3895          */
3896         public function enableSectionEditLinks( $flag = true ) {
3897                 wfDeprecated( __METHOD__, '1.31' );
3898         }
3899
3900         /**
3901          * @return bool
3902          * @since 1.23
3903          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
3904          */
3905         public function sectionEditLinksEnabled() {
3906                 wfDeprecated( __METHOD__, '1.31' );
3907                 return true;
3908         }
3909
3910         /**
3911          * Helper function to setup the PHP implementation of OOUI to use in this request.
3912          *
3913          * @since 1.26
3914          * @param String $skinName The Skin name to determine the correct OOUI theme
3915          * @param String $dir Language direction
3916          */
3917         public static function setupOOUI( $skinName = 'default', $dir = 'ltr' ) {
3918                 $themes = ResourceLoaderOOUIModule::getSkinThemeMap();
3919                 $theme = isset( $themes[$skinName] ) ? $themes[$skinName] : $themes['default'];
3920                 // For example, 'OOUI\WikimediaUITheme'.
3921                 $themeClass = "OOUI\\{$theme}Theme";
3922                 OOUI\Theme::setSingleton( new $themeClass() );
3923                 OOUI\Element::setDefaultDir( $dir );
3924         }
3925
3926         /**
3927          * Add ResourceLoader module styles for OOUI and set up the PHP implementation of it for use with
3928          * MediaWiki and this OutputPage instance.
3929          *
3930          * @since 1.25
3931          */
3932         public function enableOOUI() {
3933                 self::setupOOUI(
3934                         strtolower( $this->getSkin()->getSkinName() ),
3935                         $this->getLanguage()->getDir()
3936                 );
3937                 $this->addModuleStyles( [
3938                         'oojs-ui-core.styles',
3939                         'oojs-ui.styles.indicators',
3940                         'oojs-ui.styles.textures',
3941                         'mediawiki.widgets.styles',
3942                         'oojs-ui.styles.icons-content',
3943                         'oojs-ui.styles.icons-alerts',
3944                         'oojs-ui.styles.icons-interactions',
3945                 ] );
3946         }
3947
3948         /**
3949          * Add Link headers for preloading the wiki's logo.
3950          *
3951          * @since 1.26
3952          */
3953         protected function addLogoPreloadLinkHeaders() {
3954                 $logo = ResourceLoaderSkinModule::getLogo( $this->getConfig() );
3955
3956                 $tags = [];
3957                 $logosPerDppx = [];
3958                 $logos = [];
3959
3960                 if ( !is_array( $logo ) ) {
3961                         // No media queries required if we only have one variant
3962                         $this->addLinkHeader( '<' . $logo . '>;rel=preload;as=image' );
3963                         return;
3964                 }
3965
3966                 if ( isset( $logo['svg'] ) ) {
3967                         // No media queries required if we only have a 1x and svg variant
3968                         // because all preload-capable browsers support SVGs
3969                         $this->addLinkHeader( '<' . $logo['svg'] . '>;rel=preload;as=image' );
3970                         return;
3971                 }
3972
3973                 foreach ( $logo as $dppx => $src ) {
3974                         // Keys are in this format: "1.5x"
3975                         $dppx = substr( $dppx, 0, -1 );
3976                         $logosPerDppx[$dppx] = $src;
3977                 }
3978
3979                 // Because PHP can't have floats as array keys
3980                 uksort( $logosPerDppx, function ( $a , $b ) {
3981                         $a = floatval( $a );
3982                         $b = floatval( $b );
3983
3984                         if ( $a == $b ) {
3985                                 return 0;
3986                         }
3987                         // Sort from smallest to largest (e.g. 1x, 1.5x, 2x)
3988                         return ( $a < $b ) ? -1 : 1;
3989                 } );
3990
3991                 foreach ( $logosPerDppx as $dppx => $src ) {
3992                         $logos[] = [ 'dppx' => $dppx, 'src' => $src ];
3993                 }
3994
3995                 $logosCount = count( $logos );
3996                 // Logic must match ResourceLoaderSkinModule:
3997                 // - 1x applies to resolution < 1.5dppx
3998                 // - 1.5x applies to resolution >= 1.5dppx && < 2dppx
3999                 // - 2x applies to resolution >= 2dppx
4000                 // Note that min-resolution and max-resolution are both inclusive.
4001                 for ( $i = 0; $i < $logosCount; $i++ ) {
4002                         if ( $i === 0 ) {
4003                                 // Smallest dppx
4004                                 // min-resolution is ">=" (larger than or equal to)
4005                                 // "not min-resolution" is essentially "<"
4006                                 $media_query = 'not all and (min-resolution: ' . $logos[ 1 ]['dppx'] . 'dppx)';
4007                         } elseif ( $i !== $logosCount - 1 ) {
4008                                 // In between
4009                                 // Media query expressions can only apply "not" to the entire expression
4010                                 // (e.g. can't express ">= 1.5 and not >= 2).
4011                                 // Workaround: Use <= 1.9999 in place of < 2.
4012                                 $upper_bound = floatval( $logos[ $i + 1 ]['dppx'] ) - 0.000001;
4013                                 $media_query = '(min-resolution: ' . $logos[ $i ]['dppx'] .
4014                                         'dppx) and (max-resolution: ' . $upper_bound . 'dppx)';
4015                         } else {
4016                                 // Largest dppx
4017                                 $media_query = '(min-resolution: ' . $logos[ $i ]['dppx'] . 'dppx)';
4018                         }
4019
4020                         $this->addLinkHeader(
4021                                 '<' . $logos[$i]['src'] . '>;rel=preload;as=image;media=' . $media_query
4022                         );
4023                 }
4024         }
4025 }