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