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