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 WrappedString\WrappedString;
  27 use WrappedString\WrappedStringList;
  28
  29 /**
  30  * This class should be covered by a general architecture document which does
  31  * not exist as of January 2011.  This is one of the Core classes and should
  32  * be read at least once by any new developers.
  33  *
  34  * This class is used to prepare the final rendering. A skin is then
  35  * applied to the output parameters (links, javascript, html, categories ...).
  36  *
  37  * @todo FIXME: Another class handles sending the whole page to the client.
  38  *
  39  * Some comments comes from a pairing session between Zak Greant and Antoine Musso
  40  * in November 2010.
  41  *
  42  * @todo document
  43  */
  44 class OutputPage extends ContextSource {
  45         /** @var array Should be private. Used with addMeta() which adds "<meta>" */
  46         protected $mMetatags = [];
  47
  48         /** @var array */
  49         protected $mLinktags = [];
  50
  51         /** @var bool */
  52         protected $mCanonicalUrl = false;
  53
  54         /**
  55          * @var array Additional stylesheets. Looks like this is for extensions.
  56          *   Might be replaced by ResourceLoader.
  57          */
  58         protected $mExtStyles = [];
  59
  60         /**
  61          * @var string Should be private - has getter and setter. Contains
  62          *   the HTML title */
  63         public $mPagetitle = '';
  64
  65         /**
  66          * @var string Contains all of the "<body>" content. Should be private we
  67          *   got set/get accessors and the append() method.
  68          */
  69         public $mBodytext = '';
  70
  71         /** @var string Stores contents of "<title>" tag */
  72         private $mHTMLtitle = '';
  73
  74         /**
  75          * @var bool Is the displayed content related to the source of the
  76          *   corresponding wiki article.
  77          */
  78         private $mIsarticle = false;
  79
  80         /** @var bool Stores "article flag" toggle. */
  81         private $mIsArticleRelated = true;
  82
  83         /**
  84          * @var bool We have to set isPrintable(). Some pages should
  85          * never be printed (ex: redirections).
  86          */
  87         private $mPrintable = false;
  88
  89         /**
  90          * @var array Contains the page subtitle. Special pages usually have some
  91          *   links here. Don't confuse with site subtitle added by skins.
  92          */
  93         private $mSubtitle = [];
  94
  95         /** @var string */
  96         public $mRedirect = '';
  97
  98         /** @var int */
  99         protected $mStatusCode;
 100
 101         /**
 102          * @var string Used for sending cache control.
 103          *   The whole caching system should probably be moved into its own class.
 104          */
 105         protected $mLastModified = '';
 106
 107         /** @var array */
 108         protected $mCategoryLinks = [];
 109
 110         /** @var array */
 111         protected $mCategories = [
 112                 'hidden' => [],
 113                 'normal' => [],
 114         ];
 115
 116         /** @var array */
 117         protected $mIndicators = [];
 118
 119         /** @var array Array of Interwiki Prefixed (non DB key) Titles (e.g. 'fr:Test page') */
 120         private $mLanguageLinks = [];
 121
 122         /**
 123          * Used for JavaScript (predates ResourceLoader)
 124          * @todo We should split JS / CSS.
 125          * mScripts content is inserted as is in "<head>" by Skin. This might
 126          * contain either a link to a stylesheet or inline CSS.
 127          */
 128         private $mScripts = '';
 129
 130         /** @var string Inline CSS styles. Use addInlineStyle() sparingly */
 131         protected $mInlineStyles = '';
 132
 133         /**
 134          * @var string Used by skin template.
 135          * Example: $tpl->set( 'displaytitle', $out->mPageLinkTitle );
 136          */
 137         public $mPageLinkTitle = '';
 138
 139         /** @var array Array of elements in "<head>". Parser might add its own headers! */
 140         protected $mHeadItems = [];
 141
 142         /** @var array */
 143         protected $mModules = [];
 144
 145         /** @var array */
 146         protected $mModuleScripts = [];
 147
 148         /** @var array */
 149         protected $mModuleStyles = [];
 150
 151         /** @var ResourceLoader */
 152         protected $mResourceLoader;
 153
 154         /** @var ResourceLoaderClientHtml */
 155         private $rlClient;
 156
 157         /** @var ResourceLoaderContext */
 158         private $rlClientContext;
 159
 160         /** @var string */
 161         private $rlUserModuleState;
 162
 163         /** @var array */
 164         private $rlExemptStyleModules;
 165
 166         /** @var array */
 167         protected $mJsConfigVars = [];
 168
 169         /** @var array */
 170         protected $mTemplateIds = [];
 171
 172         /** @var array */
 173         protected $mImageTimeKeys = [];
 174
 175         /** @var string */
 176         public $mRedirectCode = '';
 177
 178         protected $mFeedLinksAppendQuery = null;
 179
 180         /** @var array
 181          * What level of 'untrustworthiness' is allowed in CSS/JS modules loaded on this page?
 182          * @see ResourceLoaderModule::$origin
 183          * ResourceLoaderModule::ORIGIN_ALL is assumed unless overridden;
 184          */
 185         protected $mAllowedModules = [
 186                 ResourceLoaderModule::TYPE_COMBINED => ResourceLoaderModule::ORIGIN_ALL,
 187         ];
 188
 189         /** @var bool Whether output is disabled.  If this is true, the 'output' method will do nothing. */
 190         protected $mDoNothing = false;
 191
 192         // Parser related.
 193
 194         /** @var int */
 195         protected $mContainsNewMagic = 0;
 196
 197         /**
 198          * lazy initialised, use parserOptions()
 199          * @var ParserOptions
 200          */
 201         protected $mParserOptions = null;
 202
 203         /**
 204          * Handles the Atom / RSS links.
 205          * We probably only support Atom in 2011.
 206          * @see $wgAdvertisedFeedTypes
 207          */
 208         private $mFeedLinks = [];
 209
 210         // Gwicke work on squid caching? Roughly from 2003.
 211         protected $mEnableClientCache = true;
 212
 213         /** @var bool Flag if output should only contain the body of the article. */
 214         private $mArticleBodyOnly = false;
 215
 216         /** @var bool */
 217         protected $mNewSectionLink = false;
 218
 219         /** @var bool */
 220         protected $mHideNewSectionLink = false;
 221
 222         /**
 223          * @var bool Comes from the parser. This was probably made to load CSS/JS
 224          * only if we had "<gallery>". Used directly in CategoryPage.php.
 225          * Looks like ResourceLoader can replace this.
 226          */
 227         public $mNoGallery = false;
 228
 229         /** @var string */
 230         private $mPageTitleActionText = '';
 231
 232         /** @var int Cache stuff. Looks like mEnableClientCache */
 233         protected $mCdnMaxage = 0;
 234         /** @var int Upper limit on mCdnMaxage */
 235         protected $mCdnMaxageLimit = INF;
 236
 237         /**
 238          * @var bool Controls if anti-clickjacking / frame-breaking headers will
 239          * be sent. This should be done for pages where edit actions are possible.
 240          * Setters: $this->preventClickjacking() and $this->allowClickjacking().
 241          */
 242         protected $mPreventClickjacking = true;
 243
 244         /** @var int To include the variable {{REVISIONID}} */
 245         private $mRevisionId = null;
 246
 247         /** @var string */
 248         private $mRevisionTimestamp = null;
 249
 250         /** @var array */
 251         protected $mFileVersion = null;
 252
 253         /**
 254          * @var array An array of stylesheet filenames (relative from skins path),
 255          * with options for CSS media, IE conditions, and RTL/LTR direction.
 256          * For internal use; add settings in the skin via $this->addStyle()
 257          *
 258          * Style again! This seems like a code duplication since we already have
 259          * mStyles. This is what makes Open Source amazing.
 260          */
 261         protected $styles = [];
 262
 263         private $mIndexPolicy = 'index';
 264         private $mFollowPolicy = 'follow';
 265         private $mVaryHeader = [
 266                 'Accept-Encoding' => [ 'match=gzip' ],
 267         ];
 268
 269         /**
 270          * If the current page was reached through a redirect, $mRedirectedFrom contains the Title
 271          * of the redirect.
 272          *
 273          * @var Title
 274          */
 275         private $mRedirectedFrom = null;
 276
 277         /**
 278          * Additional key => value data
 279          */
 280         private $mProperties = [];
 281
 282         /**
 283          * @var string|null ResourceLoader target for load.php links. If null, will be omitted
 284          */
 285         private $mTarget = null;
 286
 287         /**
 288          * @var bool Whether parser output contains a table of contents
 289          */
 290         private $mEnableTOC = false;
 291
 292         /**
 293          * @var bool Whether parser output should contain section edit links
 294          */
 295         private $mEnableSectionEditLinks = true;
 296
 297         /**
 298          * @var string|null The URL to send in a <link> element with rel=license
 299          */
 300         private $copyrightUrl;
 301
 302         /** @var array Profiling data */
 303         private $limitReportJSData = [];
 304
 305         /**
 306          * Link: header contents
 307          */
 308         private $mLinkHeader = [];
 309
 310         /**
 311          * Constructor for OutputPage. This should not be called directly.
 312          * Instead a new RequestContext should be created and it will implicitly create
 313          * a OutputPage tied to that context.
 314          * @param IContextSource|null $context
 315          */
 316         function __construct( IContextSource $context = null ) {
 317                 if ( $context === null ) {
 318                         # Extensions should use `new RequestContext` instead of `new OutputPage` now.
 319                         wfDeprecated( __METHOD__, '1.18' );
 320                 } else {
 321                         $this->setContext( $context );
 322                 }
 323         }
 324
 325         /**
 326          * Redirect to $url rather than displaying the normal page
 327          *
 328          * @param string $url URL
 329          * @param string $responsecode HTTP status code
 330          */
 331         public function redirect( $url, $responsecode = '302' ) {
 332                 # Strip newlines as a paranoia check for header injection in PHP<5.1.2
 333                 $this->mRedirect = str_replace( "\n", '', $url );
 334                 $this->mRedirectCode = $responsecode;
 335         }
 336
 337         /**
 338          * Get the URL to redirect to, or an empty string if not redirect URL set
 339          *
 340          * @return string
 341          */
 342         public function getRedirect() {
 343                 return $this->mRedirect;
 344         }
 345
 346         /**
 347          * Set the copyright URL to send with the output.
 348          * Empty string to omit, null to reset.
 349          *
 350          * @since 1.26
 351          *
 352          * @param string|null $url
 353          */
 354         public function setCopyrightUrl( $url ) {
 355                 $this->copyrightUrl = $url;
 356         }
 357
 358         /**
 359          * Set the HTTP status code to send with the output.
 360          *
 361          * @param int $statusCode
 362          */
 363         public function setStatusCode( $statusCode ) {
 364                 $this->mStatusCode = $statusCode;
 365         }
 366
 367         /**
 368          * Add a new "<meta>" tag
 369          * To add an http-equiv meta tag, precede the name with "http:"
 370          *
 371          * @param string $name Tag name
 372          * @param string $val Tag value
 373          */
 374         function addMeta( $name, $val ) {
 375                 array_push( $this->mMetatags, [ $name, $val ] );
 376         }
 377
 378         /**
 379          * Returns the current <meta> tags
 380          *
 381          * @since 1.25
 382          * @return array
 383          */
 384         public function getMetaTags() {
 385                 return $this->mMetatags;
 386         }
 387
 388         /**
 389          * Add a new \<link\> tag to the page header.
 390          *
 391          * Note: use setCanonicalUrl() for rel=canonical.
 392          *
 393          * @param array $linkarr Associative array of attributes.
 394          */
 395         function addLink( array $linkarr ) {
 396                 array_push( $this->mLinktags, $linkarr );
 397         }
 398
 399         /**
 400          * Returns the current <link> tags
 401          *
 402          * @since 1.25
 403          * @return array
 404          */
 405         public function getLinkTags() {
 406                 return $this->mLinktags;
 407         }
 408
 409         /**
 410          * Add a new \<link\> with "rel" attribute set to "meta"
 411          *
 412          * @param array $linkarr Associative array mapping attribute names to their
 413          *                 values, both keys and values will be escaped, and the
 414          *                 "rel" attribute will be automatically added
 415          */
 416         function addMetadataLink( array $linkarr ) {
 417                 $linkarr['rel'] = $this->getMetadataAttribute();
 418                 $this->addLink( $linkarr );
 419         }
 420
 421         /**
 422          * Set the URL to be used for the <link rel=canonical>. This should be used
 423          * in preference to addLink(), to avoid duplicate link tags.
 424          * @param string $url
 425          */
 426         function setCanonicalUrl( $url ) {
 427                 $this->mCanonicalUrl = $url;
 428         }
 429
 430         /**
 431          * Returns the URL to be used for the <link rel=canonical> if
 432          * one is set.
 433          *
 434          * @since 1.25
 435          * @return bool|string
 436          */
 437         public function getCanonicalUrl() {
 438                 return $this->mCanonicalUrl;
 439         }
 440
 441         /**
 442          * Get the value of the "rel" attribute for metadata links
 443          *
 444          * @return string
 445          */
 446         public function getMetadataAttribute() {
 447                 # note: buggy CC software only reads first "meta" link
 448                 static $haveMeta = false;
 449                 if ( $haveMeta ) {
 450                         return 'alternate meta';
 451                 } else {
 452                         $haveMeta = true;
 453                         return 'meta';
 454                 }
 455         }
 456
 457         /**
 458          * Add raw HTML to the list of scripts (including \<script\> tag, etc.)
 459          * Internal use only. Use OutputPage::addModules() or OutputPage::addJsConfigVars()
 460          * if possible.
 461          *
 462          * @param string $script Raw HTML
 463          */
 464         function addScript( $script ) {
 465                 $this->mScripts .= $script;
 466         }
 467
 468         /**
 469          * Register and add a stylesheet from an extension directory.
 470          *
 471          * @deprecated since 1.27 use addModuleStyles() or addStyle() instead
 472          * @param string $url Path to sheet.  Provide either a full url (beginning
 473          *             with 'http', etc) or a relative path from the document root
 474          *             (beginning with '/').  Otherwise it behaves identically to
 475          *             addStyle() and draws from the /skins folder.
 476          */
 477         public function addExtensionStyle( $url ) {
 478                 wfDeprecated( __METHOD__, '1.27' );
 479                 array_push( $this->mExtStyles, $url );
 480         }
 481
 482         /**
 483          * Get all styles added by extensions
 484          *
 485          * @deprecated since 1.27
 486          * @return array
 487          */
 488         function getExtStyle() {
 489                 wfDeprecated( __METHOD__, '1.27' );
 490                 return $this->mExtStyles;
 491         }
 492
 493         /**
 494          * Add a JavaScript file out of skins/common, or a given relative path.
 495          * Internal use only. Use OutputPage::addModules() if possible.
 496          *
 497          * @param string $file Filename in skins/common or complete on-server path
 498          *              (/foo/bar.js)
 499          * @param string $version Style version of the file. Defaults to $wgStyleVersion
 500          */
 501         public function addScriptFile( $file, $version = null ) {
 502                 // See if $file parameter is an absolute URL or begins with a slash
 503                 if ( substr( $file, 0, 1 ) == '/' || preg_match( '#^[a-z]*://#i', $file ) ) {
 504                         $path = $file;
 505                 } else {
 506                         $path = $this->getConfig()->get( 'StylePath' ) . "/common/{$file}";
 507                 }
 508                 if ( is_null( $version ) ) {
 509                         $version = $this->getConfig()->get( 'StyleVersion' );
 510                 }
 511                 $this->addScript( Html::linkedScript( wfAppendQuery( $path, $version ) ) );
 512         }
 513
 514         /**
 515          * Add a self-contained script tag with the given contents
 516          * Internal use only. Use OutputPage::addModules() if possible.
 517          *
 518          * @param string $script JavaScript text, no script tags
 519          */
 520         public function addInlineScript( $script ) {
 521                 $this->mScripts .= Html::inlineScript( $script );
 522         }
 523
 524         /**
 525          * Filter an array of modules to remove insufficiently trustworthy members, and modules
 526          * which are no longer registered (eg a page is cached before an extension is disabled)
 527          * @param array $modules
 528          * @param string|null $position If not null, only return modules with this position
 529          * @param string $type
 530          * @return array
 531          */
 532         protected function filterModules( array $modules, $position = null,
 533                 $type = ResourceLoaderModule::TYPE_COMBINED
 534         ) {
 535                 $resourceLoader = $this->getResourceLoader();
 536                 $filteredModules = [];
 537                 foreach ( $modules as $val ) {
 538                         $module = $resourceLoader->getModule( $val );
 539                         if ( $module instanceof ResourceLoaderModule
 540                                 && $module->getOrigin() <= $this->getAllowedModules( $type )
 541                                 && ( is_null( $position ) || $module->getPosition() == $position )
 542                         ) {
 543                                 if ( $this->mTarget && !in_array( $this->mTarget, $module->getTargets() ) ) {
 544                                         $this->warnModuleTargetFilter( $module->getName() );
 545                                         continue;
 546                                 }
 547                                 $filteredModules[] = $val;
 548                         }
 549                 }
 550                 return $filteredModules;
 551         }
 552
 553         private function warnModuleTargetFilter( $moduleName ) {
 554                 static $warnings = [];
 555                 if ( isset( $warnings[$this->mTarget][$moduleName] ) ) {
 556                         return;
 557                 }
 558                 $warnings[$this->mTarget][$moduleName] = true;
 559                 $this->getResourceLoader()->getLogger()->debug(
 560                         'Module "{module}" not loadable on target "{target}".',
 561                         [
 562                                 'module' => $moduleName,
 563                                 'target' => $this->mTarget,
 564                         ]
 565                 );
 566         }
 567
 568         /**
 569          * Get the list of modules to include on this page
 570          *
 571          * @param bool $filter Whether to filter out insufficiently trustworthy modules
 572          * @param string|null $position If not null, only return modules with this position
 573          * @param string $param
 574          * @param string $type
 575          * @return array Array of module names
 576          */
 577         public function getModules( $filter = false, $position = null, $param = 'mModules',
 578                 $type = ResourceLoaderModule::TYPE_COMBINED
 579         ) {
 580                 $modules = array_values( array_unique( $this->$param ) );
 581                 return $filter
 582                         ? $this->filterModules( $modules, $position, $type )
 583                         : $modules;
 584         }
 585
 586         /**
 587          * Add one or more modules recognized by ResourceLoader. Modules added
 588          * through this function will be loaded by ResourceLoader when the
 589          * page loads.
 590          *
 591          * @param string|array $modules Module name (string) or array of module names
 592          */
 593         public function addModules( $modules ) {
 594                 $this->mModules = array_merge( $this->mModules, (array)$modules );
 595         }
 596
 597         /**
 598          * Get the list of module JS to include on this page
 599          *
 600          * @param bool $filter
 601          * @param string|null $position
 602          * @return array Array of module names
 603          */
 604         public function getModuleScripts( $filter = false, $position = null ) {
 605                 return $this->getModules( $filter, $position, 'mModuleScripts',
 606                         ResourceLoaderModule::TYPE_SCRIPTS
 607                 );
 608         }
 609
 610         /**
 611          * Add only JS of one or more modules recognized by ResourceLoader. Module
 612          * scripts added through this function will be loaded by ResourceLoader when
 613          * the page loads.
 614          *
 615          * @param string|array $modules Module name (string) or array of module names
 616          */
 617         public function addModuleScripts( $modules ) {
 618                 $this->mModuleScripts = array_merge( $this->mModuleScripts, (array)$modules );
 619         }
 620
 621         /**
 622          * Get the list of module CSS to include on this page
 623          *
 624          * @param bool $filter
 625          * @param string|null $position
 626          * @return array Array of module names
 627          */
 628         public function getModuleStyles( $filter = false, $position = null ) {
 629                 return $this->getModules( $filter, $position, 'mModuleStyles',
 630                         ResourceLoaderModule::TYPE_STYLES
 631                 );
 632         }
 633
 634         /**
 635          * Add only CSS of one or more modules recognized by ResourceLoader.
 636          *
 637          * Module styles added through this function will be added using standard link CSS
 638          * tags, rather than as a combined Javascript and CSS package. Thus, they will
 639          * load when JavaScript is disabled (unless CSS also happens to be disabled).
 640          *
 641          * @param string|array $modules Module name (string) or array of module names
 642          */
 643         public function addModuleStyles( $modules ) {
 644                 $this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
 645         }
 646
 647         /**
 648          * @return null|string ResourceLoader target
 649          */
 650         public function getTarget() {
 651                 return $this->mTarget;
 652         }
 653
 654         /**
 655          * Sets ResourceLoader target for load.php links. If null, will be omitted
 656          *
 657          * @param string|null $target
 658          */
 659         public function setTarget( $target ) {
 660                 $this->mTarget = $target;
 661         }
 662
 663         /**
 664          * Get an array of head items
 665          *
 666          * @return array
 667          */
 668         function getHeadItemsArray() {
 669                 return $this->mHeadItems;
 670         }
 671
 672         /**
 673          * Add or replace a head item to the output
 674          *
 675          * Whenever possible, use more specific options like ResourceLoader modules,
 676          * OutputPage::addLink(), OutputPage::addMetaLink() and OutputPage::addFeedLink()
 677          * Fallback options for those are: OutputPage::addStyle, OutputPage::addScript(),
 678          * OutputPage::addInlineScript() and OutputPage::addInlineStyle()
 679          * This would be your very LAST fallback.
 680          *
 681          * @param string $name Item name
 682          * @param string $value Raw HTML
 683          */
 684         public function addHeadItem( $name, $value ) {
 685                 $this->mHeadItems[$name] = $value;
 686         }
 687
 688         /**
 689          * Add one or more head items to the output
 690          *
 691          * @since 1.28
 692          * @param string|string[] $values Raw HTML
 693          */
 694         public function addHeadItems( $values ) {
 695                 $this->mHeadItems = array_merge( $this->mHeadItems, (array)$values );
 696         }
 697
 698         /**
 699          * Check if the header item $name is already set
 700          *
 701          * @param string $name Item name
 702          * @return bool
 703          */
 704         public function hasHeadItem( $name ) {
 705                 return isset( $this->mHeadItems[$name] );
 706         }
 707
 708         /**
 709          * @deprecated since 1.28 Obsolete - wgUseETag experiment was removed.
 710          * @param string $tag
 711          */
 712         public function setETag( $tag ) {
 713         }
 714
 715         /**
 716          * Set whether the output should only contain the body of the article,
 717          * without any skin, sidebar, etc.
 718          * Used e.g. when calling with "action=render".
 719          *
 720          * @param bool $only Whether to output only the body of the article
 721          */
 722         public function setArticleBodyOnly( $only ) {
 723                 $this->mArticleBodyOnly = $only;
 724         }
 725
 726         /**
 727          * Return whether the output will contain only the body of the article
 728          *
 729          * @return bool
 730          */
 731         public function getArticleBodyOnly() {
 732                 return $this->mArticleBodyOnly;
 733         }
 734
 735         /**
 736          * Set an additional output property
 737          * @since 1.21
 738          *
 739          * @param string $name
 740          * @param mixed $value
 741          */
 742         public function setProperty( $name, $value ) {
 743                 $this->mProperties[$name] = $value;
 744         }
 745
 746         /**
 747          * Get an additional output property
 748          * @since 1.21
 749          *
 750          * @param string $name
 751          * @return mixed Property value or null if not found
 752          */
 753         public function getProperty( $name ) {
 754                 if ( isset( $this->mProperties[$name] ) ) {
 755                         return $this->mProperties[$name];
 756                 } else {
 757                         return null;
 758                 }
 759         }
 760
 761         /**
 762          * checkLastModified tells the client to use the client-cached page if
 763          * possible. If successful, the OutputPage is disabled so that
 764          * any future call to OutputPage->output() have no effect.
 765          *
 766          * Side effect: sets mLastModified for Last-Modified header
 767          *
 768          * @param string $timestamp
 769          *
 770          * @return bool True if cache-ok headers was sent.
 771          */
 772         public function checkLastModified( $timestamp ) {
 773                 if ( !$timestamp || $timestamp == '19700101000000' ) {
 774                         wfDebug( __METHOD__ . ": CACHE DISABLED, NO TIMESTAMP\n" );
 775                         return false;
 776                 }
 777                 $config = $this->getConfig();
 778                 if ( !$config->get( 'CachePages' ) ) {
 779                         wfDebug( __METHOD__ . ": CACHE DISABLED\n" );
 780                         return false;
 781                 }
 782
 783                 $timestamp = wfTimestamp( TS_MW, $timestamp );
 784                 $modifiedTimes = [
 785                         'page' => $timestamp,
 786                         'user' => $this->getUser()->getTouched(),
 787                         'epoch' => $config->get( 'CacheEpoch' )
 788                 ];
 789                 if ( $config->get( 'UseSquid' ) ) {
 790                         // T46570: the core page itself may not change, but resources might
 791                         $modifiedTimes['sepoch'] = wfTimestamp( TS_MW, time() - $config->get( 'SquidMaxage' ) );
 792                 }
 793                 Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this ] );
 794
 795                 $maxModified = max( $modifiedTimes );
 796                 $this->mLastModified = wfTimestamp( TS_RFC2822, $maxModified );
 797
 798                 $clientHeader = $this->getRequest()->getHeader( 'If-Modified-Since' );
 799                 if ( $clientHeader === false ) {
 800                         wfDebug( __METHOD__ . ": client did not send If-Modified-Since header", 'private' );
 801                         return false;
 802                 }
 803
 804                 # IE sends sizes after the date like this:
 805                 # Wed, 20 Aug 2003 06:51:19 GMT; length=5202
 806                 # this breaks strtotime().
 807                 $clientHeader = preg_replace( '/;.*$/', '', $clientHeader );
 808
 809                 MediaWiki\suppressWarnings(); // E_STRICT system time bitching
 810                 $clientHeaderTime = strtotime( $clientHeader );
 811                 MediaWiki\restoreWarnings();
 812                 if ( !$clientHeaderTime ) {
 813                         wfDebug( __METHOD__
 814                                 . ": unable to parse the client's If-Modified-Since header: $clientHeader\n" );
 815                         return false;
 816                 }
 817                 $clientHeaderTime = wfTimestamp( TS_MW, $clientHeaderTime );
 818
 819                 # Make debug info
 820                 $info = '';
 821                 foreach ( $modifiedTimes as $name => $value ) {
 822                         if ( $info !== '' ) {
 823                                 $info .= ', ';
 824                         }
 825                         $info .= "$name=" . wfTimestamp( TS_ISO_8601, $value );
 826                 }
 827
 828                 wfDebug( __METHOD__ . ": client sent If-Modified-Since: " .
 829                         wfTimestamp( TS_ISO_8601, $clientHeaderTime ), 'private' );
 830                 wfDebug( __METHOD__ . ": effective Last-Modified: " .
 831                         wfTimestamp( TS_ISO_8601, $maxModified ), 'private' );
 832                 if ( $clientHeaderTime < $maxModified ) {
 833                         wfDebug( __METHOD__ . ": STALE, $info", 'private' );
 834                         return false;
 835                 }
 836
 837                 # Not modified
 838                 # Give a 304 Not Modified response code and disable body output
 839                 wfDebug( __METHOD__ . ": NOT MODIFIED, $info", 'private' );
 840                 ini_set( 'zlib.output_compression', 0 );
 841                 $this->getRequest()->response()->statusHeader( 304 );
 842                 $this->sendCacheControl();
 843                 $this->disable();
 844
 845                 // Don't output a compressed blob when using ob_gzhandler;
 846                 // it's technically against HTTP spec and seems to confuse
 847                 // Firefox when the response gets split over two packets.
 848                 wfClearOutputBuffers();
 849
 850                 return true;
 851         }
 852
 853         /**
 854          * Override the last modified timestamp
 855          *
 856          * @param string $timestamp New timestamp, in a format readable by
 857          *        wfTimestamp()
 858          */
 859         public function setLastModified( $timestamp ) {
 860                 $this->mLastModified = wfTimestamp( TS_RFC2822, $timestamp );
 861         }
 862
 863         /**
 864          * Set the robot policy for the page: <http://www.robotstxt.org/meta.html>
 865          *
 866          * @param string $policy The literal string to output as the contents of
 867          *   the meta tag.  Will be parsed according to the spec and output in
 868          *   standardized form.
 869          * @return null
 870          */
 871         public function setRobotPolicy( $policy ) {
 872                 $policy = Article::formatRobotPolicy( $policy );
 873
 874                 if ( isset( $policy['index'] ) ) {
 875                         $this->setIndexPolicy( $policy['index'] );
 876                 }
 877                 if ( isset( $policy['follow'] ) ) {
 878                         $this->setFollowPolicy( $policy['follow'] );
 879                 }
 880         }
 881
 882         /**
 883          * Set the index policy for the page, but leave the follow policy un-
 884          * touched.
 885          *
 886          * @param string $policy Either 'index' or 'noindex'.
 887          * @return null
 888          */
 889         public function setIndexPolicy( $policy ) {
 890                 $policy = trim( $policy );
 891                 if ( in_array( $policy, [ 'index', 'noindex' ] ) ) {
 892                         $this->mIndexPolicy = $policy;
 893                 }
 894         }
 895
 896         /**
 897          * Set the follow policy for the page, but leave the index policy un-
 898          * touched.
 899          *
 900          * @param string $policy Either 'follow' or 'nofollow'.
 901          * @return null
 902          */
 903         public function setFollowPolicy( $policy ) {
 904                 $policy = trim( $policy );
 905                 if ( in_array( $policy, [ 'follow', 'nofollow' ] ) ) {
 906                         $this->mFollowPolicy = $policy;
 907                 }
 908         }
 909
 910         /**
 911          * Set the new value of the "action text", this will be added to the
 912          * "HTML title", separated from it with " - ".
 913          *
 914          * @param string $text New value of the "action text"
 915          */
 916         public function setPageTitleActionText( $text ) {
 917                 $this->mPageTitleActionText = $text;
 918         }
 919
 920         /**
 921          * Get the value of the "action text"
 922          *
 923          * @return string
 924          */
 925         public function getPageTitleActionText() {
 926                 return $this->mPageTitleActionText;
 927         }
 928
 929         /**
 930          * "HTML title" means the contents of "<title>".
 931          * It is stored as plain, unescaped text and will be run through htmlspecialchars in the skin file.
 932          *
 933          * @param string|Message $name
 934          */
 935         public function setHTMLTitle( $name ) {
 936                 if ( $name instanceof Message ) {
 937                         $this->mHTMLtitle = $name->setContext( $this->getContext() )->text();
 938                 } else {
 939                         $this->mHTMLtitle = $name;
 940                 }
 941         }
 942
 943         /**
 944          * Return the "HTML title", i.e. the content of the "<title>" tag.
 945          *
 946          * @return string
 947          */
 948         public function getHTMLTitle() {
 949                 return $this->mHTMLtitle;
 950         }
 951
 952         /**
 953          * Set $mRedirectedFrom, the Title of the page which redirected us to the current page.
 954          *
 955          * @param Title $t
 956          */
 957         public function setRedirectedFrom( $t ) {
 958                 $this->mRedirectedFrom = $t;
 959         }
 960
 961         /**
 962          * "Page title" means the contents of \<h1\>. It is stored as a valid HTML
 963          * fragment. This function allows good tags like \<sup\> in the \<h1\> tag,
 964          * but not bad tags like \<script\>. This function automatically sets
 965          * \<title\> to the same content as \<h1\> but with all tags removed. Bad
 966          * tags that were escaped in \<h1\> will still be escaped in \<title\>, and
 967          * good tags like \<i\> will be dropped entirely.
 968          *
 969          * @param string|Message $name
 970          */
 971         public function setPageTitle( $name ) {
 972                 if ( $name instanceof Message ) {
 973                         $name = $name->setContext( $this->getContext() )->text();
 974                 }
 975
 976                 # change "<script>foo&bar</script>" to "&lt;script&gt;foo&amp;bar&lt;/script&gt;"
 977                 # but leave "<i>foobar</i>" alone
 978                 $nameWithTags = Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $name ) );
 979                 $this->mPagetitle = $nameWithTags;
 980
 981                 # change "<i>foo&amp;bar</i>" to "foo&bar"
 982                 $this->setHTMLTitle(
 983                         $this->msg( 'pagetitle' )->rawParams( Sanitizer::stripAllTags( $nameWithTags ) )
 984                                 ->inContentLanguage()
 985                 );
 986         }
 987
 988         /**
 989          * Return the "page title", i.e. the content of the \<h1\> tag.
 990          *
 991          * @return string
 992          */
 993         public function getPageTitle() {
 994                 return $this->mPagetitle;
 995         }
 996
 997         /**
 998          * Set the Title object to use
 999          *
1000          * @param Title $t
1001          */
1002         public function setTitle( Title $t ) {
1003                 $this->getContext()->setTitle( $t );
1004         }
1005
1006         /**
1007          * Replace the subtitle with $str
1008          *
1009          * @param string|Message $str New value of the subtitle. String should be safe HTML.
1010          */
1011         public function setSubtitle( $str ) {
1012                 $this->clearSubtitle();
1013                 $this->addSubtitle( $str );
1014         }
1015
1016         /**
1017          * Add $str to the subtitle
1018          *
1019          * @param string|Message $str String or Message to add to the subtitle. String should be safe HTML.
1020          */
1021         public function addSubtitle( $str ) {
1022                 if ( $str instanceof Message ) {
1023                         $this->mSubtitle[] = $str->setContext( $this->getContext() )->parse();
1024                 } else {
1025                         $this->mSubtitle[] = $str;
1026                 }
1027         }
1028
1029         /**
1030          * Build message object for a subtitle containing a backlink to a page
1031          *
1032          * @param Title $title Title to link to
1033          * @param array $query Array of additional parameters to include in the link
1034          * @return Message
1035          * @since 1.25
1036          */
1037         public static function buildBacklinkSubtitle( Title $title, $query = [] ) {
1038                 if ( $title->isRedirect() ) {
1039                         $query['redirect'] = 'no';
1040                 }
1041                 $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1042                 return wfMessage( 'backlinksubtitle' )
1043                         ->rawParams( $linkRenderer->makeLink( $title, null, [], $query ) );
1044         }
1045
1046         /**
1047          * Add a subtitle containing a backlink to a page
1048          *
1049          * @param Title $title Title to link to
1050          * @param array $query Array of additional parameters to include in the link
1051          */
1052         public function addBacklinkSubtitle( Title $title, $query = [] ) {
1053                 $this->addSubtitle( self::buildBacklinkSubtitle( $title, $query ) );
1054         }
1055
1056         /**
1057          * Clear the subtitles
1058          */
1059         public function clearSubtitle() {
1060                 $this->mSubtitle = [];
1061         }
1062
1063         /**
1064          * Get the subtitle
1065          *
1066          * @return string
1067          */
1068         public function getSubtitle() {
1069                 return implode( "<br />\n\t\t\t\t", $this->mSubtitle );
1070         }
1071
1072         /**
1073          * Set the page as printable, i.e. it'll be displayed with all
1074          * print styles included
1075          */
1076         public function setPrintable() {
1077                 $this->mPrintable = true;
1078         }
1079
1080         /**
1081          * Return whether the page is "printable"
1082          *
1083          * @return bool
1084          */
1085         public function isPrintable() {
1086                 return $this->mPrintable;
1087         }
1088
1089         /**
1090          * Disable output completely, i.e. calling output() will have no effect
1091          */
1092         public function disable() {
1093                 $this->mDoNothing = true;
1094         }
1095
1096         /**
1097          * Return whether the output will be completely disabled
1098          *
1099          * @return bool
1100          */
1101         public function isDisabled() {
1102                 return $this->mDoNothing;
1103         }
1104
1105         /**
1106          * Show an "add new section" link?
1107          *
1108          * @return bool
1109          */
1110         public function showNewSectionLink() {
1111                 return $this->mNewSectionLink;
1112         }
1113
1114         /**
1115          * Forcibly hide the new section link?
1116          *
1117          * @return bool
1118          */
1119         public function forceHideNewSectionLink() {
1120                 return $this->mHideNewSectionLink;
1121         }
1122
1123         /**
1124          * Add or remove feed links in the page header
1125          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1126          * for the new version
1127          * @see addFeedLink()
1128          *
1129          * @param bool $show True: add default feeds, false: remove all feeds
1130          */
1131         public function setSyndicated( $show = true ) {
1132                 if ( $show ) {
1133                         $this->setFeedAppendQuery( false );
1134                 } else {
1135                         $this->mFeedLinks = [];
1136                 }
1137         }
1138
1139         /**
1140          * Add default feeds to the page header
1141          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1142          * for the new version
1143          * @see addFeedLink()
1144          *
1145          * @param string $val Query to append to feed links or false to output
1146          *        default links
1147          */
1148         public function setFeedAppendQuery( $val ) {
1149                 $this->mFeedLinks = [];
1150
1151                 foreach ( $this->getConfig()->get( 'AdvertisedFeedTypes' ) as $type ) {
1152                         $query = "feed=$type";
1153                         if ( is_string( $val ) ) {
1154                                 $query .= '&' . $val;
1155                         }
1156                         $this->mFeedLinks[$type] = $this->getTitle()->getLocalURL( $query );
1157                 }
1158         }
1159
1160         /**
1161          * Add a feed link to the page header
1162          *
1163          * @param string $format Feed type, should be a key of $wgFeedClasses
1164          * @param string $href URL
1165          */
1166         public function addFeedLink( $format, $href ) {
1167                 if ( in_array( $format, $this->getConfig()->get( 'AdvertisedFeedTypes' ) ) ) {
1168                         $this->mFeedLinks[$format] = $href;
1169                 }
1170         }
1171
1172         /**
1173          * Should we output feed links for this page?
1174          * @return bool
1175          */
1176         public function isSyndicated() {
1177                 return count( $this->mFeedLinks ) > 0;
1178         }
1179
1180         /**
1181          * Return URLs for each supported syndication format for this page.
1182          * @return array Associating format keys with URLs
1183          */
1184         public function getSyndicationLinks() {
1185                 return $this->mFeedLinks;
1186         }
1187
1188         /**
1189          * Will currently always return null
1190          *
1191          * @return null
1192          */
1193         public function getFeedAppendQuery() {
1194                 return $this->mFeedLinksAppendQuery;
1195         }
1196
1197         /**
1198          * Set whether the displayed content is related to the source of the
1199          * corresponding article on the wiki
1200          * Setting true will cause the change "article related" toggle to true
1201          *
1202          * @param bool $v
1203          */
1204         public function setArticleFlag( $v ) {
1205                 $this->mIsarticle = $v;
1206                 if ( $v ) {
1207                         $this->mIsArticleRelated = $v;
1208                 }
1209         }
1210
1211         /**
1212          * Return whether the content displayed page is related to the source of
1213          * the corresponding article on the wiki
1214          *
1215          * @return bool
1216          */
1217         public function isArticle() {
1218                 return $this->mIsarticle;
1219         }
1220
1221         /**
1222          * Set whether this page is related an article on the wiki
1223          * Setting false will cause the change of "article flag" toggle to false
1224          *
1225          * @param bool $v
1226          */
1227         public function setArticleRelated( $v ) {
1228                 $this->mIsArticleRelated = $v;
1229                 if ( !$v ) {
1230                         $this->mIsarticle = false;
1231                 }
1232         }
1233
1234         /**
1235          * Return whether this page is related an article on the wiki
1236          *
1237          * @return bool
1238          */
1239         public function isArticleRelated() {
1240                 return $this->mIsArticleRelated;
1241         }
1242
1243         /**
1244          * Add new language links
1245          *
1246          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1247          *                               (e.g. 'fr:Test page')
1248          */
1249         public function addLanguageLinks( array $newLinkArray ) {
1250                 $this->mLanguageLinks += $newLinkArray;
1251         }
1252
1253         /**
1254          * Reset the language links and add new language links
1255          *
1256          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1257          *                               (e.g. 'fr:Test page')
1258          */
1259         public function setLanguageLinks( array $newLinkArray ) {
1260                 $this->mLanguageLinks = $newLinkArray;
1261         }
1262
1263         /**
1264          * Get the list of language links
1265          *
1266          * @return string[] Array of interwiki-prefixed (non DB key) titles (e.g. 'fr:Test page')
1267          */
1268         public function getLanguageLinks() {
1269                 return $this->mLanguageLinks;
1270         }
1271
1272         /**
1273          * Add an array of categories, with names in the keys
1274          *
1275          * @param array $categories Mapping category name => sort key
1276          */
1277         public function addCategoryLinks( array $categories ) {
1278                 global $wgContLang;
1279
1280                 if ( !is_array( $categories ) || count( $categories ) == 0 ) {
1281                         return;
1282                 }
1283
1284                 $res = $this->addCategoryLinksToLBAndGetResult( $categories );
1285
1286                 # Set all the values to 'normal'.
1287                 $categories = array_fill_keys( array_keys( $categories ), 'normal' );
1288
1289                 # Mark hidden categories
1290                 foreach ( $res as $row ) {
1291                         if ( isset( $row->pp_value ) ) {
1292                                 $categories[$row->page_title] = 'hidden';
1293                         }
1294                 }
1295
1296                 // Avoid PHP 7.1 warning of passing $this by reference
1297                 $outputPage = $this;
1298                 # Add the remaining categories to the skin
1299                 if ( Hooks::run(
1300                         'OutputPageMakeCategoryLinks',
1301                         [ &$outputPage, $categories, &$this->mCategoryLinks ] )
1302                 ) {
1303                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1304                         foreach ( $categories as $category => $type ) {
1305                                 // array keys will cast numeric category names to ints, so cast back to string
1306                                 $category = (string)$category;
1307                                 $origcategory = $category;
1308                                 $title = Title::makeTitleSafe( NS_CATEGORY, $category );
1309                                 if ( !$title ) {
1310                                         continue;
1311                                 }
1312                                 $wgContLang->findVariantLink( $category, $title, true );
1313                                 if ( $category != $origcategory && array_key_exists( $category, $categories ) ) {
1314                                         continue;
1315                                 }
1316                                 $text = $wgContLang->convertHtml( $title->getText() );
1317                                 $this->mCategories[$type][] = $title->getText();
1318                                 $this->mCategoryLinks[$type][] = $linkRenderer->makeLink( $title, new HtmlArmor( $text ) );
1319                         }
1320                 }
1321         }
1322
1323         /**
1324          * @param array $categories
1325          * @return bool|ResultWrapper
1326          */
1327         protected function addCategoryLinksToLBAndGetResult( array $categories ) {
1328                 # Add the links to a LinkBatch
1329                 $arr = [ NS_CATEGORY => $categories ];
1330                 $lb = new LinkBatch;
1331                 $lb->setArray( $arr );
1332
1333                 # Fetch existence plus the hiddencat property
1334                 $dbr = wfGetDB( DB_REPLICA );
1335                 $fields = array_merge(
1336                         LinkCache::getSelectFields(),
1337                         [ 'page_namespace', 'page_title', 'pp_value' ]
1338                 );
1339
1340                 $res = $dbr->select( [ 'page', 'page_props' ],
1341                         $fields,
1342                         $lb->constructSet( 'page', $dbr ),
1343                         __METHOD__,
1344                         [],
1345                         [ 'page_props' => [ 'LEFT JOIN', [
1346                                 'pp_propname' => 'hiddencat',
1347                                 'pp_page = page_id'
1348                         ] ] ]
1349                 );
1350
1351                 # Add the results to the link cache
1352                 $lb->addResultToCache( LinkCache::singleton(), $res );
1353
1354                 return $res;
1355         }
1356
1357         /**
1358          * Reset the category links (but not the category list) and add $categories
1359          *
1360          * @param array $categories Mapping category name => sort key
1361          */
1362         public function setCategoryLinks( array $categories ) {
1363                 $this->mCategoryLinks = [];
1364                 $this->addCategoryLinks( $categories );
1365         }
1366
1367         /**
1368          * Get the list of category links, in a 2-D array with the following format:
1369          * $arr[$type][] = $link, where $type is either "normal" or "hidden" (for
1370          * hidden categories) and $link a HTML fragment with a link to the category
1371          * page
1372          *
1373          * @return array
1374          */
1375         public function getCategoryLinks() {
1376                 return $this->mCategoryLinks;
1377         }
1378
1379         /**
1380          * Get the list of category names this page belongs to.
1381          *
1382          * @param string $type The type of categories which should be returned. Possible values:
1383          *  * all: all categories of all types
1384          *  * hidden: only the hidden categories
1385          *  * normal: all categories, except hidden categories
1386          * @return array Array of strings
1387          */
1388         public function getCategories( $type = 'all' ) {
1389                 if ( $type === 'all' ) {
1390                         $allCategories = [];
1391                         foreach ( $this->mCategories as $categories ) {
1392                                 $allCategories = array_merge( $allCategories, $categories );
1393                         }
1394                         return $allCategories;
1395                 }
1396                 if ( !isset( $this->mCategories[$type] ) ) {
1397                         throw new InvalidArgumentException( 'Invalid category type given: ' . $type );
1398                 }
1399                 return $this->mCategories[$type];
1400         }
1401
1402         /**
1403          * Add an array of indicators, with their identifiers as array
1404          * keys and HTML contents as values.
1405          *
1406          * In case of duplicate keys, existing values are overwritten.
1407          *
1408          * @param array $indicators
1409          * @since 1.25
1410          */
1411         public function setIndicators( array $indicators ) {
1412                 $this->mIndicators = $indicators + $this->mIndicators;
1413                 // Keep ordered by key
1414                 ksort( $this->mIndicators );
1415         }
1416
1417         /**
1418          * Get the indicators associated with this page.
1419          *
1420          * The array will be internally ordered by item keys.
1421          *
1422          * @return array Keys: identifiers, values: HTML contents
1423          * @since 1.25
1424          */
1425         public function getIndicators() {
1426                 return $this->mIndicators;
1427         }
1428
1429         /**
1430          * Adds help link with an icon via page indicators.
1431          * Link target can be overridden by a local message containing a wikilink:
1432          * the message key is: lowercase action or special page name + '-helppage'.
1433          * @param string $to Target MediaWiki.org page title or encoded URL.
1434          * @param bool $overrideBaseUrl Whether $url is a full URL, to avoid MW.o.
1435          * @since 1.25
1436          */
1437         public function addHelpLink( $to, $overrideBaseUrl = false ) {
1438                 $this->addModuleStyles( 'mediawiki.helplink' );
1439                 $text = $this->msg( 'helppage-top-gethelp' )->escaped();
1440
1441                 if ( $overrideBaseUrl ) {
1442                         $helpUrl = $to;
1443                 } else {
1444                         $toUrlencoded = wfUrlencode( str_replace( ' ', '_', $to ) );
1445                         $helpUrl = "//www.mediawiki.org/wiki/Special:MyLanguage/$toUrlencoded";
1446                 }
1447
1448                 $link = Html::rawElement(
1449                         'a',
1450                         [
1451                                 'href' => $helpUrl,
1452                                 'target' => '_blank',
1453                                 'class' => 'mw-helplink',
1454                         ],
1455                         $text
1456                 );
1457
1458                 $this->setIndicators( [ 'mw-helplink' => $link ] );
1459         }
1460
1461         /**
1462          * Do not allow scripts which can be modified by wiki users to load on this page;
1463          * only allow scripts bundled with, or generated by, the software.
1464          * Site-wide styles are controlled by a config setting, since they can be
1465          * used to create a custom skin/theme, but not user-specific ones.
1466          *
1467          * @todo this should be given a more accurate name
1468          */
1469         public function disallowUserJs() {
1470                 $this->reduceAllowedModules(
1471                         ResourceLoaderModule::TYPE_SCRIPTS,
1472                         ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
1473                 );
1474
1475                 // Site-wide styles are controlled by a config setting, see T73621
1476                 // for background on why. User styles are never allowed.
1477                 if ( $this->getConfig()->get( 'AllowSiteCSSOnRestrictedPages' ) ) {
1478                         $styleOrigin = ResourceLoaderModule::ORIGIN_USER_SITEWIDE;
1479                 } else {
1480                         $styleOrigin = ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL;
1481                 }
1482                 $this->reduceAllowedModules(
1483                         ResourceLoaderModule::TYPE_STYLES,
1484                         $styleOrigin
1485                 );
1486         }
1487
1488         /**
1489          * Show what level of JavaScript / CSS untrustworthiness is allowed on this page
1490          * @see ResourceLoaderModule::$origin
1491          * @param string $type ResourceLoaderModule TYPE_ constant
1492          * @return int ResourceLoaderModule ORIGIN_ class constant
1493          */
1494         public function getAllowedModules( $type ) {
1495                 if ( $type == ResourceLoaderModule::TYPE_COMBINED ) {
1496                         return min( array_values( $this->mAllowedModules ) );
1497                 } else {
1498                         return isset( $this->mAllowedModules[$type] )
1499                                 ? $this->mAllowedModules[$type]
1500                                 : ResourceLoaderModule::ORIGIN_ALL;
1501                 }
1502         }
1503
1504         /**
1505          * Limit the highest level of CSS/JS untrustworthiness allowed.
1506          *
1507          * If passed the same or a higher level than the current level of untrustworthiness set, the
1508          * level will remain unchanged.
1509          *
1510          * @param string $type
1511          * @param int $level ResourceLoaderModule class constant
1512          */
1513         public function reduceAllowedModules( $type, $level ) {
1514                 $this->mAllowedModules[$type] = min( $this->getAllowedModules( $type ), $level );
1515         }
1516
1517         /**
1518          * Prepend $text to the body HTML
1519          *
1520          * @param string $text HTML
1521          */
1522         public function prependHTML( $text ) {
1523                 $this->mBodytext = $text . $this->mBodytext;
1524         }
1525
1526         /**
1527          * Append $text to the body HTML
1528          *
1529          * @param string $text HTML
1530          */
1531         public function addHTML( $text ) {
1532                 $this->mBodytext .= $text;
1533         }
1534
1535         /**
1536          * Shortcut for adding an Html::element via addHTML.
1537          *
1538          * @since 1.19
1539          *
1540          * @param string $element
1541          * @param array $attribs
1542          * @param string $contents
1543          */
1544         public function addElement( $element, array $attribs = [], $contents = '' ) {
1545                 $this->addHTML( Html::element( $element, $attribs, $contents ) );
1546         }
1547
1548         /**
1549          * Clear the body HTML
1550          */
1551         public function clearHTML() {
1552                 $this->mBodytext = '';
1553         }
1554
1555         /**
1556          * Get the body HTML
1557          *
1558          * @return string HTML
1559          */
1560         public function getHTML() {
1561                 return $this->mBodytext;
1562         }
1563
1564         /**
1565          * Get/set the ParserOptions object to use for wikitext parsing
1566          *
1567          * @param ParserOptions|null $options Either the ParserOption to use or null to only get the
1568          *   current ParserOption object
1569          * @return ParserOptions
1570          */
1571         public function parserOptions( $options = null ) {
1572                 if ( $options !== null && !empty( $options->isBogus ) ) {
1573                         // Someone is trying to set a bogus pre-$wgUser PO. Check if it has
1574                         // been changed somehow, and keep it if so.
1575                         $anonPO = ParserOptions::newFromAnon();
1576                         $anonPO->setEditSection( false );
1577                         $anonPO->setAllowUnsafeRawHtml( false );
1578                         if ( !$options->matches( $anonPO ) ) {
1579                                 wfLogWarning( __METHOD__ . ': Setting a changed bogus ParserOptions: ' . wfGetAllCallers( 5 ) );
1580                                 $options->isBogus = false;
1581                         }
1582                 }
1583
1584                 if ( !$this->mParserOptions ) {
1585                         if ( !$this->getContext()->getUser()->isSafeToLoad() ) {
1586                                 // $wgUser isn't unstubbable yet, so don't try to get a
1587                                 // ParserOptions for it. And don't cache this ParserOptions
1588                                 // either.
1589                                 $po = ParserOptions::newFromAnon();
1590                                 $po->setEditSection( false );
1591                                 $po->setAllowUnsafeRawHtml( false );
1592                                 $po->isBogus = true;
1593                                 if ( $options !== null ) {
1594                                         $this->mParserOptions = empty( $options->isBogus ) ? $options : null;
1595                                 }
1596                                 return $po;
1597                         }
1598
1599                         $this->mParserOptions = ParserOptions::newFromContext( $this->getContext() );
1600                         $this->mParserOptions->setEditSection( false );
1601                         $this->mParserOptions->setAllowUnsafeRawHtml( false );
1602                 }
1603
1604                 if ( $options !== null && !empty( $options->isBogus ) ) {
1605                         // They're trying to restore the bogus pre-$wgUser PO. Do the right
1606                         // thing.
1607                         return wfSetVar( $this->mParserOptions, null, true );
1608                 } else {
1609                         return wfSetVar( $this->mParserOptions, $options );
1610                 }
1611         }
1612
1613         /**
1614          * Set the revision ID which will be seen by the wiki text parser
1615          * for things such as embedded {{REVISIONID}} variable use.
1616          *
1617          * @param int|null $revid An positive integer, or null
1618          * @return mixed Previous value
1619          */
1620         public function setRevisionId( $revid ) {
1621                 $val = is_null( $revid ) ? null : intval( $revid );
1622                 return wfSetVar( $this->mRevisionId, $val );
1623         }
1624
1625         /**
1626          * Get the displayed revision ID
1627          *
1628          * @return int
1629          */
1630         public function getRevisionId() {
1631                 return $this->mRevisionId;
1632         }
1633
1634         /**
1635          * Set the timestamp of the revision which will be displayed. This is used
1636          * to avoid a extra DB call in Skin::lastModified().
1637          *
1638          * @param string|null $timestamp
1639          * @return mixed Previous value
1640          */
1641         public function setRevisionTimestamp( $timestamp ) {
1642                 return wfSetVar( $this->mRevisionTimestamp, $timestamp );
1643         }
1644
1645         /**
1646          * Get the timestamp of displayed revision.
1647          * This will be null if not filled by setRevisionTimestamp().
1648          *
1649          * @return string|null
1650          */
1651         public function getRevisionTimestamp() {
1652                 return $this->mRevisionTimestamp;
1653         }
1654
1655         /**
1656          * Set the displayed file version
1657          *
1658          * @param File|bool $file
1659          * @return mixed Previous value
1660          */
1661         public function setFileVersion( $file ) {
1662                 $val = null;
1663                 if ( $file instanceof File && $file->exists() ) {
1664                         $val = [ 'time' => $file->getTimestamp(), 'sha1' => $file->getSha1() ];
1665                 }
1666                 return wfSetVar( $this->mFileVersion, $val, true );
1667         }
1668
1669         /**
1670          * Get the displayed file version
1671          *
1672          * @return array|null ('time' => MW timestamp, 'sha1' => sha1)
1673          */
1674         public function getFileVersion() {
1675                 return $this->mFileVersion;
1676         }
1677
1678         /**
1679          * Get the templates used on this page
1680          *
1681          * @return array (namespace => dbKey => revId)
1682          * @since 1.18
1683          */
1684         public function getTemplateIds() {
1685                 return $this->mTemplateIds;
1686         }
1687
1688         /**
1689          * Get the files used on this page
1690          *
1691          * @return array (dbKey => array('time' => MW timestamp or null, 'sha1' => sha1 or ''))
1692          * @since 1.18
1693          */
1694         public function getFileSearchOptions() {
1695                 return $this->mImageTimeKeys;
1696         }
1697
1698         /**
1699          * Convert wikitext to HTML and add it to the buffer
1700          * Default assumes that the current page title will be used.
1701          *
1702          * @param string $text
1703          * @param bool $linestart Is this the start of a line?
1704          * @param bool $interface Is this text in the user interface language?
1705          * @throws MWException
1706          */
1707         public function addWikiText( $text, $linestart = true, $interface = true ) {
1708                 $title = $this->getTitle(); // Work around E_STRICT
1709                 if ( !$title ) {
1710                         throw new MWException( 'Title is null' );
1711                 }
1712                 $this->addWikiTextTitle( $text, $title, $linestart, /*tidy*/false, $interface );
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          */
1722         public function addWikiTextWithTitle( $text, &$title, $linestart = true ) {
1723                 $this->addWikiTextTitle( $text, $title, $linestart );
1724         }
1725
1726         /**
1727          * Add wikitext with a custom Title object and tidy enabled.
1728          *
1729          * @param string $text Wikitext
1730          * @param Title &$title
1731          * @param bool $linestart Is this the start of a line?
1732          */
1733         function addWikiTextTitleTidy( $text, &$title, $linestart = true ) {
1734                 $this->addWikiTextTitle( $text, $title, $linestart, true );
1735         }
1736
1737         /**
1738          * Add wikitext with tidy enabled
1739          *
1740          * @param string $text Wikitext
1741          * @param bool $linestart Is this the start of a line?
1742          */
1743         public function addWikiTextTidy( $text, $linestart = true ) {
1744                 $title = $this->getTitle();
1745                 $this->addWikiTextTitleTidy( $text, $title, $linestart );
1746         }
1747
1748         /**
1749          * Add wikitext with a custom Title object
1750          *
1751          * @param string $text Wikitext
1752          * @param Title $title
1753          * @param bool $linestart Is this the start of a line?
1754          * @param bool $tidy Whether to use tidy
1755          * @param bool $interface Whether it is an interface message
1756          *   (for example disables conversion)
1757          */
1758         public function addWikiTextTitle( $text, Title $title, $linestart,
1759                 $tidy = false, $interface = false
1760         ) {
1761                 global $wgParser;
1762
1763                 $popts = $this->parserOptions();
1764                 $oldTidy = $popts->setTidy( $tidy );
1765                 $popts->setInterfaceMessage( (bool)$interface );
1766
1767                 $parserOutput = $wgParser->getFreshParser()->parse(
1768                         $text, $title, $popts,
1769                         $linestart, true, $this->mRevisionId
1770                 );
1771
1772                 $popts->setTidy( $oldTidy );
1773
1774                 $this->addParserOutput( $parserOutput );
1775         }
1776
1777         /**
1778          * Add all metadata associated with a ParserOutput object, but without the actual HTML. This
1779          * includes categories, language links, ResourceLoader modules, effects of certain magic words,
1780          * and so on.
1781          *
1782          * @since 1.24
1783          * @param ParserOutput $parserOutput
1784          */
1785         public function addParserOutputMetadata( $parserOutput ) {
1786                 $this->mLanguageLinks += $parserOutput->getLanguageLinks();
1787                 $this->addCategoryLinks( $parserOutput->getCategories() );
1788                 $this->setIndicators( $parserOutput->getIndicators() );
1789                 $this->mNewSectionLink = $parserOutput->getNewSection();
1790                 $this->mHideNewSectionLink = $parserOutput->getHideNewSection();
1791
1792                 if ( !$parserOutput->isCacheable() ) {
1793                         $this->enableClientCache( false );
1794                 }
1795                 $this->mNoGallery = $parserOutput->getNoGallery();
1796                 $this->mHeadItems = array_merge( $this->mHeadItems, $parserOutput->getHeadItems() );
1797                 $this->addModules( $parserOutput->getModules() );
1798                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1799                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1800                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1801                 $this->mPreventClickjacking = $this->mPreventClickjacking
1802                         || $parserOutput->preventClickjacking();
1803
1804                 // Template versioning...
1805                 foreach ( (array)$parserOutput->getTemplateIds() as $ns => $dbks ) {
1806                         if ( isset( $this->mTemplateIds[$ns] ) ) {
1807                                 $this->mTemplateIds[$ns] = $dbks + $this->mTemplateIds[$ns];
1808                         } else {
1809                                 $this->mTemplateIds[$ns] = $dbks;
1810                         }
1811                 }
1812                 // File versioning...
1813                 foreach ( (array)$parserOutput->getFileSearchOptions() as $dbk => $data ) {
1814                         $this->mImageTimeKeys[$dbk] = $data;
1815                 }
1816
1817                 // Hooks registered in the object
1818                 $parserOutputHooks = $this->getConfig()->get( 'ParserOutputHooks' );
1819                 foreach ( $parserOutput->getOutputHooks() as $hookInfo ) {
1820                         list( $hookName, $data ) = $hookInfo;
1821                         if ( isset( $parserOutputHooks[$hookName] ) ) {
1822                                 call_user_func( $parserOutputHooks[$hookName], $this, $parserOutput, $data );
1823                         }
1824                 }
1825
1826                 // Enable OOUI if requested via ParserOutput
1827                 if ( $parserOutput->getEnableOOUI() ) {
1828                         $this->enableOOUI();
1829                 }
1830
1831                 // Include parser limit report
1832                 if ( !$this->limitReportJSData ) {
1833                         $this->limitReportJSData = $parserOutput->getLimitReportJSData();
1834                 }
1835
1836                 // Link flags are ignored for now, but may in the future be
1837                 // used to mark individual language links.
1838                 $linkFlags = [];
1839                 // Avoid PHP 7.1 warning of passing $this by reference
1840                 $outputPage = $this;
1841                 Hooks::run( 'LanguageLinks', [ $this->getTitle(), &$this->mLanguageLinks, &$linkFlags ] );
1842                 Hooks::run( 'OutputPageParserOutput', [ &$outputPage, $parserOutput ] );
1843
1844                 // This check must be after 'OutputPageParserOutput' runs in addParserOutputMetadata
1845                 // so that extensions may modify ParserOutput to toggle TOC.
1846                 // This cannot be moved to addParserOutputText because that is not
1847                 // called by EditPage for Preview.
1848                 if ( $parserOutput->getTOCEnabled() && $parserOutput->getTOCHTML() ) {
1849                         $this->mEnableTOC = true;
1850                 }
1851         }
1852
1853         /**
1854          * Add the HTML and enhancements for it (like ResourceLoader modules) associated with a
1855          * ParserOutput object, without any other metadata.
1856          *
1857          * @since 1.24
1858          * @param ParserOutput $parserOutput
1859          */
1860         public function addParserOutputContent( $parserOutput ) {
1861                 $this->addParserOutputText( $parserOutput );
1862
1863                 $this->addModules( $parserOutput->getModules() );
1864                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1865                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1866
1867                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1868         }
1869
1870         /**
1871          * Add the HTML associated with a ParserOutput object, without any metadata.
1872          *
1873          * @since 1.24
1874          * @param ParserOutput $parserOutput
1875          */
1876         public function addParserOutputText( $parserOutput ) {
1877                 $text = $parserOutput->getText();
1878                 // Avoid PHP 7.1 warning of passing $this by reference
1879                 $outputPage = $this;
1880                 Hooks::run( 'OutputPageBeforeHTML', [ &$outputPage, &$text ] );
1881                 $this->addHTML( $text );
1882         }
1883
1884         /**
1885          * Add everything from a ParserOutput object.
1886          *
1887          * @param ParserOutput $parserOutput
1888          */
1889         function addParserOutput( $parserOutput ) {
1890                 $this->addParserOutputMetadata( $parserOutput );
1891
1892                 // Touch section edit links only if not previously disabled
1893                 if ( $parserOutput->getEditSectionTokens() ) {
1894                         $parserOutput->setEditSectionTokens( $this->mEnableSectionEditLinks );
1895                 }
1896
1897                 $this->addParserOutputText( $parserOutput );
1898         }
1899
1900         /**
1901          * Add the output of a QuickTemplate to the output buffer
1902          *
1903          * @param QuickTemplate &$template
1904          */
1905         public function addTemplate( &$template ) {
1906                 $this->addHTML( $template->getHTML() );
1907         }
1908
1909         /**
1910          * Parse wikitext and return the HTML.
1911          *
1912          * @param string $text
1913          * @param bool $linestart Is this the start of a line?
1914          * @param bool $interface Use interface language ($wgLang instead of
1915          *   $wgContLang) while parsing language sensitive magic words like GRAMMAR and PLURAL.
1916          *   This also disables LanguageConverter.
1917          * @param Language $language Target language object, will override $interface
1918          * @throws MWException
1919          * @return string HTML
1920          */
1921         public function parse( $text, $linestart = true, $interface = false, $language = null ) {
1922                 global $wgParser;
1923
1924                 if ( is_null( $this->getTitle() ) ) {
1925                         throw new MWException( 'Empty $mTitle in ' . __METHOD__ );
1926                 }
1927
1928                 $popts = $this->parserOptions();
1929                 if ( $interface ) {
1930                         $popts->setInterfaceMessage( true );
1931                 }
1932                 if ( $language !== null ) {
1933                         $oldLang = $popts->setTargetLanguage( $language );
1934                 }
1935
1936                 $parserOutput = $wgParser->getFreshParser()->parse(
1937                         $text, $this->getTitle(), $popts,
1938                         $linestart, true, $this->mRevisionId
1939                 );
1940
1941                 if ( $interface ) {
1942                         $popts->setInterfaceMessage( false );
1943                 }
1944                 if ( $language !== null ) {
1945                         $popts->setTargetLanguage( $oldLang );
1946                 }
1947
1948                 return $parserOutput->getText();
1949         }
1950
1951         /**
1952          * Parse wikitext, strip paragraphs, and return the HTML.
1953          *
1954          * @param string $text
1955          * @param bool $linestart Is this the start of a line?
1956          * @param bool $interface Use interface language ($wgLang instead of
1957          *   $wgContLang) while parsing language sensitive magic
1958          *   words like GRAMMAR and PLURAL
1959          * @return string HTML
1960          */
1961         public function parseInline( $text, $linestart = true, $interface = false ) {
1962                 $parsed = $this->parse( $text, $linestart, $interface );
1963                 return Parser::stripOuterParagraph( $parsed );
1964         }
1965
1966         /**
1967          * @param int $maxage
1968          * @deprecated since 1.27 Use setCdnMaxage() instead
1969          */
1970         public function setSquidMaxage( $maxage ) {
1971                 $this->setCdnMaxage( $maxage );
1972         }
1973
1974         /**
1975          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header
1976          *
1977          * @param int $maxage Maximum cache time on the CDN, in seconds.
1978          */
1979         public function setCdnMaxage( $maxage ) {
1980                 $this->mCdnMaxage = min( $maxage, $this->mCdnMaxageLimit );
1981         }
1982
1983         /**
1984          * Lower the value of the "s-maxage" part of the "Cache-control" HTTP header
1985          *
1986          * @param int $maxage Maximum cache time on the CDN, in seconds
1987          * @since 1.27
1988          */
1989         public function lowerCdnMaxage( $maxage ) {
1990                 $this->mCdnMaxageLimit = min( $maxage, $this->mCdnMaxageLimit );
1991                 $this->setCdnMaxage( $this->mCdnMaxage );
1992         }
1993
1994         /**
1995          * Get TTL in [$minTTL,$maxTTL] in pass it to lowerCdnMaxage()
1996          *
1997          * This sets and returns $minTTL if $mtime is false or null. Otherwise,
1998          * the TTL is higher the older the $mtime timestamp is. Essentially, the
1999          * TTL is 90% of the age of the object, subject to the min and max.
2000          *
2001          * @param string|integer|float|bool|null $mtime Last-Modified timestamp
2002          * @param integer $minTTL Mimimum TTL in seconds [default: 1 minute]
2003          * @param integer $maxTTL Maximum TTL in seconds [default: $wgSquidMaxage]
2004          * @return integer TTL in seconds
2005          * @since 1.28
2006          */
2007         public function adaptCdnTTL( $mtime, $minTTL = 0, $maxTTL = 0 ) {
2008                 $minTTL = $minTTL ?: IExpiringStore::TTL_MINUTE;
2009                 $maxTTL = $maxTTL ?: $this->getConfig()->get( 'SquidMaxage' );
2010
2011                 if ( $mtime === null || $mtime === false ) {
2012                         return $minTTL; // entity does not exist
2013                 }
2014
2015                 $age = time() - wfTimestamp( TS_UNIX, $mtime );
2016                 $adaptiveTTL = max( .9 * $age, $minTTL );
2017                 $adaptiveTTL = min( $adaptiveTTL, $maxTTL );
2018
2019                 $this->lowerCdnMaxage( (int)$adaptiveTTL );
2020
2021                 return $adaptiveTTL;
2022         }
2023
2024         /**
2025          * Use enableClientCache(false) to force it to send nocache headers
2026          *
2027          * @param bool $state
2028          *
2029          * @return bool
2030          */
2031         public function enableClientCache( $state ) {
2032                 return wfSetVar( $this->mEnableClientCache, $state );
2033         }
2034
2035         /**
2036          * Get the list of cookies that will influence on the cache
2037          *
2038          * @return array
2039          */
2040         function getCacheVaryCookies() {
2041                 static $cookies;
2042                 if ( $cookies === null ) {
2043                         $config = $this->getConfig();
2044                         $cookies = array_merge(
2045                                 SessionManager::singleton()->getVaryCookies(),
2046                                 [
2047                                         'forceHTTPS',
2048                                 ],
2049                                 $config->get( 'CacheVaryCookies' )
2050                         );
2051                         Hooks::run( 'GetCacheVaryCookies', [ $this, &$cookies ] );
2052                 }
2053                 return $cookies;
2054         }
2055
2056         /**
2057          * Check if the request has a cache-varying cookie header
2058          * If it does, it's very important that we don't allow public caching
2059          *
2060          * @return bool
2061          */
2062         function haveCacheVaryCookies() {
2063                 $request = $this->getRequest();
2064                 foreach ( $this->getCacheVaryCookies() as $cookieName ) {
2065                         if ( $request->getCookie( $cookieName, '', '' ) !== '' ) {
2066                                 wfDebug( __METHOD__ . ": found $cookieName\n" );
2067                                 return true;
2068                         }
2069                 }
2070                 wfDebug( __METHOD__ . ": no cache-varying cookies found\n" );
2071                 return false;
2072         }
2073
2074         /**
2075          * Add an HTTP header that will influence on the cache
2076          *
2077          * @param string $header Header name
2078          * @param string[]|null $option Options for the Key header. See
2079          * https://datatracker.ietf.org/doc/draft-fielding-http-key/
2080          * for the list of valid options.
2081          */
2082         public function addVaryHeader( $header, array $option = null ) {
2083                 if ( !array_key_exists( $header, $this->mVaryHeader ) ) {
2084                         $this->mVaryHeader[$header] = [];
2085                 }
2086                 if ( !is_array( $option ) ) {
2087                         $option = [];
2088                 }
2089                 $this->mVaryHeader[$header] = array_unique( array_merge( $this->mVaryHeader[$header], $option ) );
2090         }
2091
2092         /**
2093          * Return a Vary: header on which to vary caches. Based on the keys of $mVaryHeader,
2094          * such as Accept-Encoding or Cookie
2095          *
2096          * @return string
2097          */
2098         public function getVaryHeader() {
2099                 // If we vary on cookies, let's make sure it's always included here too.
2100                 if ( $this->getCacheVaryCookies() ) {
2101                         $this->addVaryHeader( 'Cookie' );
2102                 }
2103
2104                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2105                         $this->addVaryHeader( $header, $options );
2106                 }
2107                 return 'Vary: ' . implode( ', ', array_keys( $this->mVaryHeader ) );
2108         }
2109
2110         /**
2111          * Add an HTTP Link: header
2112          *
2113          * @param string $header Header value
2114          */
2115         public function addLinkHeader( $header ) {
2116                 $this->mLinkHeader[] = $header;
2117         }
2118
2119         /**
2120          * Return a Link: header. Based on the values of $mLinkHeader.
2121          *
2122          * @return string
2123          */
2124         public function getLinkHeader() {
2125                 if ( !$this->mLinkHeader ) {
2126                         return false;
2127                 }
2128
2129                 return 'Link: ' . implode( ',', $this->mLinkHeader );
2130         }
2131
2132         /**
2133          * Get a complete Key header
2134          *
2135          * @return string
2136          */
2137         public function getKeyHeader() {
2138                 $cvCookies = $this->getCacheVaryCookies();
2139
2140                 $cookiesOption = [];
2141                 foreach ( $cvCookies as $cookieName ) {
2142                         $cookiesOption[] = 'param=' . $cookieName;
2143                 }
2144                 $this->addVaryHeader( 'Cookie', $cookiesOption );
2145
2146                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2147                         $this->addVaryHeader( $header, $options );
2148                 }
2149
2150                 $headers = [];
2151                 foreach ( $this->mVaryHeader as $header => $option ) {
2152                         $newheader = $header;
2153                         if ( is_array( $option ) && count( $option ) > 0 ) {
2154                                 $newheader .= ';' . implode( ';', $option );
2155                         }
2156                         $headers[] = $newheader;
2157                 }
2158                 $key = 'Key: ' . implode( ',', $headers );
2159
2160                 return $key;
2161         }
2162
2163         /**
2164          * T23672: Add Accept-Language to Vary and Key headers
2165          * if there's no 'variant' parameter existed in GET.
2166          *
2167          * For example:
2168          *   /w/index.php?title=Main_page should always be served; but
2169          *   /w/index.php?title=Main_page&variant=zh-cn should never be served.
2170          */
2171         function addAcceptLanguage() {
2172                 $title = $this->getTitle();
2173                 if ( !$title instanceof Title ) {
2174                         return;
2175                 }
2176
2177                 $lang = $title->getPageLanguage();
2178                 if ( !$this->getRequest()->getCheck( 'variant' ) && $lang->hasVariants() ) {
2179                         $variants = $lang->getVariants();
2180                         $aloption = [];
2181                         foreach ( $variants as $variant ) {
2182                                 if ( $variant === $lang->getCode() ) {
2183                                         continue;
2184                                 } else {
2185                                         $aloption[] = 'substr=' . $variant;
2186
2187                                         // IE and some other browsers use BCP 47 standards in
2188                                         // their Accept-Language header, like "zh-CN" or "zh-Hant".
2189                                         // We should handle these too.
2190                                         $variantBCP47 = wfBCP47( $variant );
2191                                         if ( $variantBCP47 !== $variant ) {
2192                                                 $aloption[] = 'substr=' . $variantBCP47;
2193                                         }
2194                                 }
2195                         }
2196                         $this->addVaryHeader( 'Accept-Language', $aloption );
2197                 }
2198         }
2199
2200         /**
2201          * Set a flag which will cause an X-Frame-Options header appropriate for
2202          * edit pages to be sent. The header value is controlled by
2203          * $wgEditPageFrameOptions.
2204          *
2205          * This is the default for special pages. If you display a CSRF-protected
2206          * form on an ordinary view page, then you need to call this function.
2207          *
2208          * @param bool $enable
2209          */
2210         public function preventClickjacking( $enable = true ) {
2211                 $this->mPreventClickjacking = $enable;
2212         }
2213
2214         /**
2215          * Turn off frame-breaking. Alias for $this->preventClickjacking(false).
2216          * This can be called from pages which do not contain any CSRF-protected
2217          * HTML form.
2218          */
2219         public function allowClickjacking() {
2220                 $this->mPreventClickjacking = false;
2221         }
2222
2223         /**
2224          * Get the prevent-clickjacking flag
2225          *
2226          * @since 1.24
2227          * @return bool
2228          */
2229         public function getPreventClickjacking() {
2230                 return $this->mPreventClickjacking;
2231         }
2232
2233         /**
2234          * Get the X-Frame-Options header value (without the name part), or false
2235          * if there isn't one. This is used by Skin to determine whether to enable
2236          * JavaScript frame-breaking, for clients that don't support X-Frame-Options.
2237          *
2238          * @return string|false
2239          */
2240         public function getFrameOptions() {
2241                 $config = $this->getConfig();
2242                 if ( $config->get( 'BreakFrames' ) ) {
2243                         return 'DENY';
2244                 } elseif ( $this->mPreventClickjacking && $config->get( 'EditPageFrameOptions' ) ) {
2245                         return $config->get( 'EditPageFrameOptions' );
2246                 }
2247                 return false;
2248         }
2249
2250         /**
2251          * Send cache control HTTP headers
2252          */
2253         public function sendCacheControl() {
2254                 $response = $this->getRequest()->response();
2255                 $config = $this->getConfig();
2256
2257                 $this->addVaryHeader( 'Cookie' );
2258                 $this->addAcceptLanguage();
2259
2260                 # don't serve compressed data to clients who can't handle it
2261                 # maintain different caches for logged-in users and non-logged in ones
2262                 $response->header( $this->getVaryHeader() );
2263
2264                 if ( $config->get( 'UseKeyHeader' ) ) {
2265                         $response->header( $this->getKeyHeader() );
2266                 }
2267
2268                 if ( $this->mEnableClientCache ) {
2269                         if (
2270                                 $config->get( 'UseSquid' ) &&
2271                                 !$response->hasCookies() &&
2272                                 !SessionManager::getGlobalSession()->isPersistent() &&
2273                                 !$this->isPrintable() &&
2274                                 $this->mCdnMaxage != 0 &&
2275                                 !$this->haveCacheVaryCookies()
2276                         ) {
2277                                 if ( $config->get( 'UseESI' ) ) {
2278                                         # We'll purge the proxy cache explicitly, but require end user agents
2279                                         # to revalidate against the proxy on each visit.
2280                                         # Surrogate-Control controls our CDN, Cache-Control downstream caches
2281                                         wfDebug( __METHOD__ .
2282                                                 ": proxy caching with ESI; {$this->mLastModified} **", 'private' );
2283                                         # start with a shorter timeout for initial testing
2284                                         # header( 'Surrogate-Control: max-age=2678400+2678400, content="ESI/1.0"');
2285                                         $response->header(
2286                                                 "Surrogate-Control: max-age={$config->get( 'SquidMaxage' )}" .
2287                                                 "+{$this->mCdnMaxage}, content=\"ESI/1.0\""
2288                                         );
2289                                         $response->header( 'Cache-Control: s-maxage=0, must-revalidate, max-age=0' );
2290                                 } else {
2291                                         # We'll purge the proxy cache for anons explicitly, but require end user agents
2292                                         # to revalidate against the proxy on each visit.
2293                                         # IMPORTANT! The CDN needs to replace the Cache-Control header with
2294                                         # Cache-Control: s-maxage=0, must-revalidate, max-age=0
2295                                         wfDebug( __METHOD__ .
2296                                                 ": local proxy caching; {$this->mLastModified} **", 'private' );
2297                                         # start with a shorter timeout for initial testing
2298                                         # header( "Cache-Control: s-maxage=2678400, must-revalidate, max-age=0" );
2299                                         $response->header( "Cache-Control: " .
2300                                                 "s-maxage={$this->mCdnMaxage}, must-revalidate, max-age=0" );
2301                                 }
2302                         } else {
2303                                 # We do want clients to cache if they can, but they *must* check for updates
2304                                 # on revisiting the page.
2305                                 wfDebug( __METHOD__ . ": private caching; {$this->mLastModified} **", 'private' );
2306                                 $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2307                                 $response->header( "Cache-Control: private, must-revalidate, max-age=0" );
2308                         }
2309                         if ( $this->mLastModified ) {
2310                                 $response->header( "Last-Modified: {$this->mLastModified}" );
2311                         }
2312                 } else {
2313                         wfDebug( __METHOD__ . ": no caching **", 'private' );
2314
2315                         # In general, the absence of a last modified header should be enough to prevent
2316                         # the client from using its cache. We send a few other things just to make sure.
2317                         $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2318                         $response->header( 'Cache-Control: no-cache, no-store, max-age=0, must-revalidate' );
2319                         $response->header( 'Pragma: no-cache' );
2320                 }
2321         }
2322
2323         /**
2324          * Finally, all the text has been munged and accumulated into
2325          * the object, let's actually output it:
2326          *
2327          * @param bool $return Set to true to get the result as a string rather than sending it
2328          * @return string|null
2329          * @throws Exception
2330          * @throws FatalError
2331          * @throws MWException
2332          */
2333         public function output( $return = false ) {
2334                 global $wgContLang;
2335
2336                 if ( $this->mDoNothing ) {
2337                         return $return ? '' : null;
2338                 }
2339
2340                 $response = $this->getRequest()->response();
2341                 $config = $this->getConfig();
2342
2343                 if ( $this->mRedirect != '' ) {
2344                         # Standards require redirect URLs to be absolute
2345                         $this->mRedirect = wfExpandUrl( $this->mRedirect, PROTO_CURRENT );
2346
2347                         $redirect = $this->mRedirect;
2348                         $code = $this->mRedirectCode;
2349
2350                         if ( Hooks::run( "BeforePageRedirect", [ $this, &$redirect, &$code ] ) ) {
2351                                 if ( $code == '301' || $code == '303' ) {
2352                                         if ( !$config->get( 'DebugRedirects' ) ) {
2353                                                 $response->statusHeader( $code );
2354                                         }
2355                                         $this->mLastModified = wfTimestamp( TS_RFC2822 );
2356                                 }
2357                                 if ( $config->get( 'VaryOnXFP' ) ) {
2358                                         $this->addVaryHeader( 'X-Forwarded-Proto' );
2359                                 }
2360                                 $this->sendCacheControl();
2361
2362                                 $response->header( "Content-Type: text/html; charset=utf-8" );
2363                                 if ( $config->get( 'DebugRedirects' ) ) {
2364                                         $url = htmlspecialchars( $redirect );
2365                                         print "<!DOCTYPE html>\n<html>\n<head>\n<title>Redirect</title>\n</head>\n<body>\n";
2366                                         print "<p>Location: <a href=\"$url\">$url</a></p>\n";
2367                                         print "</body>\n</html>\n";
2368                                 } else {
2369                                         $response->header( 'Location: ' . $redirect );
2370                                 }
2371                         }
2372
2373                         return $return ? '' : null;
2374                 } elseif ( $this->mStatusCode ) {
2375                         $response->statusHeader( $this->mStatusCode );
2376                 }
2377
2378                 # Buffer output; final headers may depend on later processing
2379                 ob_start();
2380
2381                 $response->header( 'Content-type: ' . $config->get( 'MimeType' ) . '; charset=UTF-8' );
2382                 $response->header( 'Content-language: ' . $wgContLang->getHtmlCode() );
2383
2384                 // Avoid Internet Explorer "compatibility view" in IE 8-10, so that
2385                 // jQuery etc. can work correctly.
2386                 $response->header( 'X-UA-Compatible: IE=Edge' );
2387
2388                 if ( !$this->mArticleBodyOnly ) {
2389                         $sk = $this->getSkin();
2390
2391                         if ( $sk->shouldPreloadLogo() ) {
2392                                 $this->addLogoPreloadLinkHeaders();
2393                         }
2394                 }
2395
2396                 $linkHeader = $this->getLinkHeader();
2397                 if ( $linkHeader ) {
2398                         $response->header( $linkHeader );
2399                 }
2400
2401                 // Prevent framing, if requested
2402                 $frameOptions = $this->getFrameOptions();
2403                 if ( $frameOptions ) {
2404                         $response->header( "X-Frame-Options: $frameOptions" );
2405                 }
2406
2407                 if ( $this->mArticleBodyOnly ) {
2408                         echo $this->mBodytext;
2409                 } else {
2410                         // Enable safe mode if requested
2411                         if ( $this->getRequest()->getBool( 'safemode' ) ) {
2412                                 $this->disallowUserJs();
2413                         }
2414
2415                         $sk = $this->getSkin();
2416                         foreach ( $sk->getDefaultModules() as $group ) {
2417                                 $this->addModules( $group );
2418                         }
2419
2420                         MWDebug::addModules( $this );
2421
2422                         // Avoid PHP 7.1 warning of passing $this by reference
2423                         $outputPage = $this;
2424                         // Hook that allows last minute changes to the output page, e.g.
2425                         // adding of CSS or Javascript by extensions.
2426                         Hooks::run( 'BeforePageDisplay', [ &$outputPage, &$sk ] );
2427
2428                         try {
2429                                 $sk->outputPage();
2430                         } catch ( Exception $e ) {
2431                                 ob_end_clean(); // bug T129657
2432                                 throw $e;
2433                         }
2434                 }
2435
2436                 try {
2437                         // This hook allows last minute changes to final overall output by modifying output buffer
2438                         Hooks::run( 'AfterFinalPageOutput', [ $this ] );
2439                 } catch ( Exception $e ) {
2440                         ob_end_clean(); // bug T129657
2441                         throw $e;
2442                 }
2443
2444                 $this->sendCacheControl();
2445
2446                 if ( $return ) {
2447                         return ob_get_clean();
2448                 } else {
2449                         ob_end_flush();
2450                         return null;
2451                 }
2452         }
2453
2454         /**
2455          * Prepare this object to display an error page; disable caching and
2456          * indexing, clear the current text and redirect, set the page's title
2457          * and optionally an custom HTML title (content of the "<title>" tag).
2458          *
2459          * @param string|Message $pageTitle Will be passed directly to setPageTitle()
2460          * @param string|Message $htmlTitle Will be passed directly to setHTMLTitle();
2461          *                   optional, if not passed the "<title>" attribute will be
2462          *                   based on $pageTitle
2463          */
2464         public function prepareErrorPage( $pageTitle, $htmlTitle = false ) {
2465                 $this->setPageTitle( $pageTitle );
2466                 if ( $htmlTitle !== false ) {
2467                         $this->setHTMLTitle( $htmlTitle );
2468                 }
2469                 $this->setRobotPolicy( 'noindex,nofollow' );
2470                 $this->setArticleRelated( false );
2471                 $this->enableClientCache( false );
2472                 $this->mRedirect = '';
2473                 $this->clearSubtitle();
2474                 $this->clearHTML();
2475         }
2476
2477         /**
2478          * Output a standard error page
2479          *
2480          * showErrorPage( 'titlemsg', 'pagetextmsg' );
2481          * showErrorPage( 'titlemsg', 'pagetextmsg', [ 'param1', 'param2' ] );
2482          * showErrorPage( 'titlemsg', $messageObject );
2483          * showErrorPage( $titleMessageObject, $messageObject );
2484          *
2485          * @param string|Message $title Message key (string) for page title, or a Message object
2486          * @param string|Message $msg Message key (string) for page text, or a Message object
2487          * @param array $params Message parameters; ignored if $msg is a Message object
2488          */
2489         public function showErrorPage( $title, $msg, $params = [] ) {
2490                 if ( !$title instanceof Message ) {
2491                         $title = $this->msg( $title );
2492                 }
2493
2494                 $this->prepareErrorPage( $title );
2495
2496                 if ( $msg instanceof Message ) {
2497                         if ( $params !== [] ) {
2498                                 trigger_error( 'Argument ignored: $params. The message parameters argument '
2499                                         . 'is discarded when the $msg argument is a Message object instead of '
2500                                         . 'a string.', E_USER_NOTICE );
2501                         }
2502                         $this->addHTML( $msg->parseAsBlock() );
2503                 } else {
2504                         $this->addWikiMsgArray( $msg, $params );
2505                 }
2506
2507                 $this->returnToMain();
2508         }
2509
2510         /**
2511          * Output a standard permission error page
2512          *
2513          * @param array $errors Error message keys or [key, param...] arrays
2514          * @param string $action Action that was denied or null if unknown
2515          */
2516         public function showPermissionsErrorPage( array $errors, $action = null ) {
2517                 foreach ( $errors as $key => $error ) {
2518                         $errors[$key] = (array)$error;
2519                 }
2520
2521                 // For some action (read, edit, create and upload), display a "login to do this action"
2522                 // error if all of the following conditions are met:
2523                 // 1. the user is not logged in
2524                 // 2. the only error is insufficient permissions (i.e. no block or something else)
2525                 // 3. the error can be avoided simply by logging in
2526                 if ( in_array( $action, [ 'read', 'edit', 'createpage', 'createtalk', 'upload' ] )
2527                         && $this->getUser()->isAnon() && count( $errors ) == 1 && isset( $errors[0][0] )
2528                         && ( $errors[0][0] == 'badaccess-groups' || $errors[0][0] == 'badaccess-group0' )
2529                         && ( User::groupHasPermission( 'user', $action )
2530                         || User::groupHasPermission( 'autoconfirmed', $action ) )
2531                 ) {
2532                         $displayReturnto = null;
2533
2534                         # Due to T34276, if a user does not have read permissions,
2535                         # $this->getTitle() will just give Special:Badtitle, which is
2536                         # not especially useful as a returnto parameter. Use the title
2537                         # from the request instead, if there was one.
2538                         $request = $this->getRequest();
2539                         $returnto = Title::newFromText( $request->getVal( 'title', '' ) );
2540                         if ( $action == 'edit' ) {
2541                                 $msg = 'whitelistedittext';
2542                                 $displayReturnto = $returnto;
2543                         } elseif ( $action == 'createpage' || $action == 'createtalk' ) {
2544                                 $msg = 'nocreatetext';
2545                         } elseif ( $action == 'upload' ) {
2546                                 $msg = 'uploadnologintext';
2547                         } else { # Read
2548                                 $msg = 'loginreqpagetext';
2549                                 $displayReturnto = Title::newMainPage();
2550                         }
2551
2552                         $query = [];
2553
2554                         if ( $returnto ) {
2555                                 $query['returnto'] = $returnto->getPrefixedText();
2556
2557                                 if ( !$request->wasPosted() ) {
2558                                         $returntoquery = $request->getValues();
2559                                         unset( $returntoquery['title'] );
2560                                         unset( $returntoquery['returnto'] );
2561                                         unset( $returntoquery['returntoquery'] );
2562                                         $query['returntoquery'] = wfArrayToCgi( $returntoquery );
2563                                 }
2564                         }
2565                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
2566                         $loginLink = $linkRenderer->makeKnownLink(
2567                                 SpecialPage::getTitleFor( 'Userlogin' ),
2568                                 $this->msg( 'loginreqlink' )->text(),
2569                                 [],
2570                                 $query
2571                         );
2572
2573                         $this->prepareErrorPage( $this->msg( 'loginreqtitle' ) );
2574                         $this->addHTML( $this->msg( $msg )->rawParams( $loginLink )->parse() );
2575
2576                         # Don't return to a page the user can't read otherwise
2577                         # we'll end up in a pointless loop
2578                         if ( $displayReturnto && $displayReturnto->userCan( 'read', $this->getUser() ) ) {
2579                                 $this->returnToMain( null, $displayReturnto );
2580                         }
2581                 } else {
2582                         $this->prepareErrorPage( $this->msg( 'permissionserrors' ) );
2583                         $this->addWikiText( $this->formatPermissionsErrorMessage( $errors, $action ) );
2584                 }
2585         }
2586
2587         /**
2588          * Display an error page indicating that a given version of MediaWiki is
2589          * required to use it
2590          *
2591          * @param mixed $version The version of MediaWiki needed to use the page
2592          */
2593         public function versionRequired( $version ) {
2594                 $this->prepareErrorPage( $this->msg( 'versionrequired', $version ) );
2595
2596                 $this->addWikiMsg( 'versionrequiredtext', $version );
2597                 $this->returnToMain();
2598         }
2599
2600         /**
2601          * Format a list of error messages
2602          *
2603          * @param array $errors Array of arrays returned by Title::getUserPermissionsErrors
2604          * @param string $action Action that was denied or null if unknown
2605          * @return string The wikitext error-messages, formatted into a list.
2606          */
2607         public function formatPermissionsErrorMessage( array $errors, $action = null ) {
2608                 if ( $action == null ) {
2609                         $text = $this->msg( 'permissionserrorstext', count( $errors ) )->plain() . "\n\n";
2610                 } else {
2611                         $action_desc = $this->msg( "action-$action" )->plain();
2612                         $text = $this->msg(
2613                                 'permissionserrorstext-withaction',
2614                                 count( $errors ),
2615                                 $action_desc
2616                         )->plain() . "\n\n";
2617                 }
2618
2619                 if ( count( $errors ) > 1 ) {
2620                         $text .= '<ul class="permissions-errors">' . "\n";
2621
2622                         foreach ( $errors as $error ) {
2623                                 $text .= '<li>';
2624                                 $text .= call_user_func_array( [ $this, 'msg' ], $error )->plain();
2625                                 $text .= "</li>\n";
2626                         }
2627                         $text .= '</ul>';
2628                 } else {
2629                         $text .= "<div class=\"permissions-errors\">\n" .
2630                                         call_user_func_array( [ $this, 'msg' ], reset( $errors ) )->plain() .
2631                                         "\n</div>";
2632                 }
2633
2634                 return $text;
2635         }
2636
2637         /**
2638          * Display a page stating that the Wiki is in read-only mode.
2639          * Should only be called after wfReadOnly() has returned true.
2640          *
2641          * Historically, this function was used to show the source of the page that the user
2642          * was trying to edit and _also_ permissions error messages. The relevant code was
2643          * moved into EditPage in 1.19 (r102024 / d83c2a431c2a) and removed here in 1.25.
2644          *
2645          * @deprecated since 1.25; throw the exception directly
2646          * @throws ReadOnlyError
2647          */
2648         public function readOnlyPage() {
2649                 if ( func_num_args() > 0 ) {
2650                         throw new MWException( __METHOD__ . ' no longer accepts arguments since 1.25.' );
2651                 }
2652
2653                 throw new ReadOnlyError;
2654         }
2655
2656         /**
2657          * Turn off regular page output and return an error response
2658          * for when rate limiting has triggered.
2659          *
2660          * @deprecated since 1.25; throw the exception directly
2661          */
2662         public function rateLimited() {
2663                 wfDeprecated( __METHOD__, '1.25' );
2664                 throw new ThrottledError;
2665         }
2666
2667         /**
2668          * Show a warning about replica DB lag
2669          *
2670          * If the lag is higher than $wgSlaveLagCritical seconds,
2671          * then the warning is a bit more obvious. If the lag is
2672          * lower than $wgSlaveLagWarning, then no warning is shown.
2673          *
2674          * @param int $lag Slave lag
2675          */
2676         public function showLagWarning( $lag ) {
2677                 $config = $this->getConfig();
2678                 if ( $lag >= $config->get( 'SlaveLagWarning' ) ) {
2679                         $lag = floor( $lag ); // floor to avoid nano seconds to display
2680                         $message = $lag < $config->get( 'SlaveLagCritical' )
2681                                 ? 'lag-warn-normal'
2682                                 : 'lag-warn-high';
2683                         $wrap = Html::rawElement( 'div', [ 'class' => "mw-{$message}" ], "\n$1\n" );
2684                         $this->wrapWikiMsg( "$wrap\n", [ $message, $this->getLanguage()->formatNum( $lag ) ] );
2685                 }
2686         }
2687
2688         public function showFatalError( $message ) {
2689                 $this->prepareErrorPage( $this->msg( 'internalerror' ) );
2690
2691                 $this->addHTML( $message );
2692         }
2693
2694         public function showUnexpectedValueError( $name, $val ) {
2695                 $this->showFatalError( $this->msg( 'unexpected', $name, $val )->text() );
2696         }
2697
2698         public function showFileCopyError( $old, $new ) {
2699                 $this->showFatalError( $this->msg( 'filecopyerror', $old, $new )->text() );
2700         }
2701
2702         public function showFileRenameError( $old, $new ) {
2703                 $this->showFatalError( $this->msg( 'filerenameerror', $old, $new )->text() );
2704         }
2705
2706         public function showFileDeleteError( $name ) {
2707                 $this->showFatalError( $this->msg( 'filedeleteerror', $name )->text() );
2708         }
2709
2710         public function showFileNotFoundError( $name ) {
2711                 $this->showFatalError( $this->msg( 'filenotfound', $name )->text() );
2712         }
2713
2714         /**
2715          * Add a "return to" link pointing to a specified title
2716          *
2717          * @param Title $title Title to link
2718          * @param array $query Query string parameters
2719          * @param string $text Text of the link (input is not escaped)
2720          * @param array $options Options array to pass to Linker
2721          */
2722         public function addReturnTo( $title, array $query = [], $text = null, $options = [] ) {
2723                 $linkRenderer = MediaWikiServices::getInstance()
2724                         ->getLinkRendererFactory()->createFromLegacyOptions( $options );
2725                 $link = $this->msg( 'returnto' )->rawParams(
2726                         $linkRenderer->makeLink( $title, $text, [], $query ) )->escaped();
2727                 $this->addHTML( "<p id=\"mw-returnto\">{$link}</p>\n" );
2728         }
2729
2730         /**
2731          * Add a "return to" link pointing to a specified title,
2732          * or the title indicated in the request, or else the main page
2733          *
2734          * @param mixed $unused
2735          * @param Title|string $returnto Title or String to return to
2736          * @param string $returntoquery Query string for the return to link
2737          */
2738         public function returnToMain( $unused = null, $returnto = null, $returntoquery = null ) {
2739                 if ( $returnto == null ) {
2740                         $returnto = $this->getRequest()->getText( 'returnto' );
2741                 }
2742
2743                 if ( $returntoquery == null ) {
2744                         $returntoquery = $this->getRequest()->getText( 'returntoquery' );
2745                 }
2746
2747                 if ( $returnto === '' ) {
2748                         $returnto = Title::newMainPage();
2749                 }
2750
2751                 if ( is_object( $returnto ) ) {
2752                         $titleObj = $returnto;
2753                 } else {
2754                         $titleObj = Title::newFromText( $returnto );
2755                 }
2756                 // We don't want people to return to external interwiki. That
2757                 // might potentially be used as part of a phishing scheme
2758                 if ( !is_object( $titleObj ) || $titleObj->isExternal() ) {
2759                         $titleObj = Title::newMainPage();
2760                 }
2761
2762                 $this->addReturnTo( $titleObj, wfCgiToArray( $returntoquery ) );
2763         }
2764
2765         private function getRlClientContext() {
2766                 if ( !$this->rlClientContext ) {
2767                         $query = ResourceLoader::makeLoaderQuery(
2768                                 [], // modules; not relevant
2769                                 $this->getLanguage()->getCode(),
2770                                 $this->getSkin()->getSkinName(),
2771                                 $this->getUser()->isLoggedIn() ? $this->getUser()->getName() : null,
2772                                 null, // version; not relevant
2773                                 ResourceLoader::inDebugMode(),
2774                                 null, // only; not relevant
2775                                 $this->isPrintable(),
2776                                 $this->getRequest()->getBool( 'handheld' )
2777                         );
2778                         $this->rlClientContext = new ResourceLoaderContext(
2779                                 $this->getResourceLoader(),
2780                                 new FauxRequest( $query )
2781                         );
2782                 }
2783                 return $this->rlClientContext;
2784         }
2785
2786         /**
2787          * Call this to freeze the module queue and JS config and create a formatter.
2788          *
2789          * Depending on the Skin, this may get lazy-initialised in either headElement() or
2790          * getBottomScripts(). See SkinTemplate::prepareQuickTemplate(). Calling this too early may
2791          * cause unexpected side-effects since disallowUserJs() may be called at any time to change
2792          * the module filters retroactively. Skins and extension hooks may also add modules until very
2793          * late in the request lifecycle.
2794          *
2795          * @return ResourceLoaderClientHtml
2796          */
2797         public function getRlClient() {
2798                 if ( !$this->rlClient ) {
2799                         $context = $this->getRlClientContext();
2800                         $rl = $this->getResourceLoader();
2801                         $this->addModules( [
2802                                 'user.options',
2803                                 'user.tokens',
2804                         ] );
2805                         $this->addModuleStyles( [
2806                                 'site.styles',
2807                                 'noscript',
2808                                 'user.styles',
2809                         ] );
2810                         $this->getSkin()->setupSkinUserCss( $this );
2811
2812                         // Prepare exempt modules for buildExemptModules()
2813                         $exemptGroups = [ 'site' => [], 'noscript' => [], 'private' => [], 'user' => [] ];
2814                         $exemptStates = [];
2815                         $moduleStyles = $this->getModuleStyles( /*filter*/ true );
2816
2817                         // Preload getTitleInfo for isKnownEmpty calls below and in ResourceLoaderClientHtml
2818                         // Separate user-specific batch for improved cache-hit ratio.
2819                         $userBatch = [ 'user.styles', 'user' ];
2820                         $siteBatch = array_diff( $moduleStyles, $userBatch );
2821                         $dbr = wfGetDB( DB_REPLICA );
2822                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $siteBatch );
2823                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $userBatch );
2824
2825                         // Filter out modules handled by buildExemptModules()
2826                         $moduleStyles = array_filter( $moduleStyles,
2827                                 function ( $name ) use ( $rl, $context, &$exemptGroups, &$exemptStates ) {
2828                                         $module = $rl->getModule( $name );
2829                                         if ( $module ) {
2830                                                 if ( $name === 'user.styles' && $this->isUserCssPreview() ) {
2831                                                         $exemptStates[$name] = 'ready';
2832                                                         // Special case in buildExemptModules()
2833                                                         return false;
2834                                                 }
2835                                                 $group = $module->getGroup();
2836                                                 if ( isset( $exemptGroups[$group] ) ) {
2837                                                         $exemptStates[$name] = 'ready';
2838                                                         if ( !$module->isKnownEmpty( $context ) ) {
2839                                                                 // E.g. Don't output empty <styles>
2840                                                                 $exemptGroups[$group][] = $name;
2841                                                         }
2842                                                         return false;
2843                                                 }
2844                                         }
2845                                         return true;
2846                                 }
2847                         );
2848                         $this->rlExemptStyleModules = $exemptGroups;
2849
2850                         $isUserModuleFiltered = !$this->filterModules( [ 'user' ] );
2851                         // If this page filters out 'user', makeResourceLoaderLink will drop it.
2852                         // Avoid indefinite "loading" state or untrue "ready" state (T145368).
2853                         if ( !$isUserModuleFiltered ) {
2854                                 // Manually handled by getBottomScripts()
2855                                 $userModule = $rl->getModule( 'user' );
2856                                 $userState = $userModule->isKnownEmpty( $context ) && !$this->isUserJsPreview()
2857                                         ? 'ready'
2858                                         : 'loading';
2859                                 $this->rlUserModuleState = $exemptStates['user'] = $userState;
2860                         }
2861
2862                         $rlClient = new ResourceLoaderClientHtml( $context, $this->getTarget() );
2863                         $rlClient->setConfig( $this->getJSVars() );
2864                         $rlClient->setModules( $this->getModules( /*filter*/ true ) );
2865                         $rlClient->setModuleStyles( $moduleStyles );
2866                         $rlClient->setModuleScripts( $this->getModuleScripts( /*filter*/ true ) );
2867                         $rlClient->setExemptStates( $exemptStates );
2868                         $this->rlClient = $rlClient;
2869                 }
2870                 return $this->rlClient;
2871         }
2872
2873         /**
2874          * @param Skin $sk The given Skin
2875          * @param bool $includeStyle Unused
2876          * @return string The doctype, opening "<html>", and head element.
2877          */
2878         public function headElement( Skin $sk, $includeStyle = true ) {
2879                 global $wgContLang;
2880
2881                 $userdir = $this->getLanguage()->getDir();
2882                 $sitedir = $wgContLang->getDir();
2883
2884                 $pieces = [];
2885                 $pieces[] = Html::htmlHeader( Sanitizer::mergeAttributes(
2886                         $this->getRlClient()->getDocumentAttributes(),
2887                         $sk->getHtmlElementAttributes()
2888                 ) );
2889                 $pieces[] = Html::openElement( 'head' );
2890
2891                 if ( $this->getHTMLTitle() == '' ) {
2892                         $this->setHTMLTitle( $this->msg( 'pagetitle', $this->getPageTitle() )->inContentLanguage() );
2893                 }
2894
2895                 if ( !Html::isXmlMimeType( $this->getConfig()->get( 'MimeType' ) ) ) {
2896                         // Add <meta charset="UTF-8">
2897                         // This should be before <title> since it defines the charset used by
2898                         // text including the text inside <title>.
2899                         // The spec recommends defining XHTML5's charset using the XML declaration
2900                         // instead of meta.
2901                         // Our XML declaration is output by Html::htmlHeader.
2902                         // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-content-type
2903                         // https://html.spec.whatwg.org/multipage/semantics.html#charset
2904                         $pieces[] = Html::element( 'meta', [ 'charset' => 'UTF-8' ] );
2905                 }
2906
2907                 $pieces[] = Html::element( 'title', null, $this->getHTMLTitle() );
2908                 $pieces[] = $this->getRlClient()->getHeadHtml();
2909                 $pieces[] = $this->buildExemptModules();
2910                 $pieces = array_merge( $pieces, array_values( $this->getHeadLinksArray() ) );
2911                 $pieces = array_merge( $pieces, array_values( $this->mHeadItems ) );
2912
2913                 $min = ResourceLoader::inDebugMode() ? '' : '.min';
2914                 // Use an IE conditional comment to serve the script only to old IE
2915                 $pieces[] = '<!--[if lt IE 9]>' .
2916                         Html::element( 'script', [
2917                                 'src' => self::transformResourcePath(
2918                                         $this->getConfig(),
2919                                         "/resources/lib/html5shiv/html5shiv{$min}.js"
2920                                 ),
2921                         ] ) .
2922                         '<![endif]-->';
2923
2924                 $pieces[] = Html::closeElement( 'head' );
2925
2926                 $bodyClasses = [];
2927                 $bodyClasses[] = 'mediawiki';
2928
2929                 # Classes for LTR/RTL directionality support
2930                 $bodyClasses[] = $userdir;
2931                 $bodyClasses[] = "sitedir-$sitedir";
2932
2933                 $underline = $this->getUser()->getOption( 'underline' );
2934                 if ( $underline < 2 ) {
2935                         // The following classes can be used here:
2936                         // * mw-underline-always
2937                         // * mw-underline-never
2938                         $bodyClasses[] = 'mw-underline-' . ( $underline ? 'always' : 'never' );
2939                 }
2940
2941                 if ( $this->getLanguage()->capitalizeAllNouns() ) {
2942                         # A <body> class is probably not the best way to do this . . .
2943                         $bodyClasses[] = 'capitalize-all-nouns';
2944                 }
2945
2946                 // Parser feature migration class
2947                 // The idea is that this will eventually be removed, after the wikitext
2948                 // which requires it is cleaned up.
2949                 $bodyClasses[] = 'mw-hide-empty-elt';
2950
2951                 $bodyClasses[] = $sk->getPageClasses( $this->getTitle() );
2952                 $bodyClasses[] = 'skin-' . Sanitizer::escapeClass( $sk->getSkinName() );
2953                 $bodyClasses[] =
2954                         'action-' . Sanitizer::escapeClass( Action::getActionName( $this->getContext() ) );
2955
2956                 $bodyAttrs = [];
2957                 // While the implode() is not strictly needed, it's used for backwards compatibility
2958                 // (this used to be built as a string and hooks likely still expect that).
2959                 $bodyAttrs['class'] = implode( ' ', $bodyClasses );
2960
2961                 // Allow skins and extensions to add body attributes they need
2962                 $sk->addToBodyAttributes( $this, $bodyAttrs );
2963                 Hooks::run( 'OutputPageBodyAttributes', [ $this, $sk, &$bodyAttrs ] );
2964
2965                 $pieces[] = Html::openElement( 'body', $bodyAttrs );
2966
2967                 return self::combineWrappedStrings( $pieces );
2968         }
2969
2970         /**
2971          * Get a ResourceLoader object associated with this OutputPage
2972          *
2973          * @return ResourceLoader
2974          */
2975         public function getResourceLoader() {
2976                 if ( is_null( $this->mResourceLoader ) ) {
2977                         $this->mResourceLoader = new ResourceLoader(
2978                                 $this->getConfig(),
2979                                 LoggerFactory::getInstance( 'resourceloader' )
2980                         );
2981                 }
2982                 return $this->mResourceLoader;
2983         }
2984
2985         /**
2986          * Explicily load or embed modules on a page.
2987          *
2988          * @param array|string $modules One or more module names
2989          * @param string $only ResourceLoaderModule TYPE_ class constant
2990          * @param array $extraQuery [optional] Array with extra query parameters for the request
2991          * @return string|WrappedStringList HTML
2992          */
2993         public function makeResourceLoaderLink( $modules, $only, array $extraQuery = [] ) {
2994                 // Apply 'target' and 'origin' filters
2995                 $modules = $this->filterModules( (array)$modules, null, $only );
2996
2997                 return ResourceLoaderClientHtml::makeLoad(
2998                         $this->getRlClientContext(),
2999                         $modules,
3000                         $only,
3001                         $extraQuery
3002                 );
3003         }
3004
3005         /**
3006          * Combine WrappedString chunks and filter out empty ones
3007          *
3008          * @param array $chunks
3009          * @return string|WrappedStringList HTML
3010          */
3011         protected static function combineWrappedStrings( array $chunks ) {
3012                 // Filter out empty values
3013                 $chunks = array_filter( $chunks, 'strlen' );
3014                 return WrappedString::join( "\n", $chunks );
3015         }
3016
3017         private function isUserJsPreview() {
3018                 return $this->getConfig()->get( 'AllowUserJs' )
3019                         && $this->getTitle()
3020                         && $this->getTitle()->isJsSubpage()
3021                         && $this->userCanPreview();
3022         }
3023
3024         protected function isUserCssPreview() {
3025                 return $this->getConfig()->get( 'AllowUserCss' )
3026                         && $this->getTitle()
3027                         && $this->getTitle()->isCssSubpage()
3028                         && $this->userCanPreview();
3029         }
3030
3031         /**
3032          * JS stuff to put at the bottom of the `<body>`. These are modules with position 'bottom',
3033          * legacy scripts ($this->mScripts), and user JS.
3034          *
3035          * @return string|WrappedStringList HTML
3036          */
3037         public function getBottomScripts() {
3038                 $chunks = [];
3039                 $chunks[] = $this->getRlClient()->getBodyHtml();
3040
3041                 // Legacy non-ResourceLoader scripts
3042                 $chunks[] = $this->mScripts;
3043
3044                 // Exempt 'user' module
3045                 // - May need excludepages for live preview. (T28283)
3046                 // - Must use TYPE_COMBINED so its response is handled by mw.loader.implement() which
3047                 //   ensures execution is scheduled after the "site" module.
3048                 // - Don't load if module state is already resolved as "ready".
3049                 if ( $this->rlUserModuleState === 'loading' ) {
3050                         if ( $this->isUserJsPreview() ) {
3051                                 $chunks[] = $this->makeResourceLoaderLink( 'user', ResourceLoaderModule::TYPE_COMBINED,
3052                                         [ 'excludepage' => $this->getTitle()->getPrefixedDBkey() ]
3053                                 );
3054                                 $chunks[] = ResourceLoader::makeInlineScript(
3055                                         Xml::encodeJsCall( 'mw.loader.using', [
3056                                                 [ 'user', 'site' ],
3057                                                 new XmlJsCode(
3058                                                         'function () {'
3059                                                                 . Xml::encodeJsCall( '$.globalEval', [
3060                                                                         $this->getRequest()->getText( 'wpTextbox1' )
3061                                                                 ] )
3062                                                                 . '}'
3063                                                 )
3064                                         ] )
3065                                 );
3066                                 // FIXME: If the user is previewing, say, ./vector.js, his ./common.js will be loaded
3067                                 // asynchronously and may arrive *after* the inline script here. So the previewed code
3068                                 // may execute before ./common.js runs. Normally, ./common.js runs before ./vector.js.
3069                                 // Similarly, when previewing ./common.js and the user module does arrive first,
3070                                 // it will arrive without common.js and the inline script runs after.
3071                                 // Thus running common after the excluded subpage.
3072                         } else {
3073                                 // Load normally
3074                                 $chunks[] = $this->makeResourceLoaderLink( 'user', ResourceLoaderModule::TYPE_COMBINED );
3075                         }
3076                 }
3077
3078                 if ( $this->limitReportJSData ) {
3079                         $chunks[] = ResourceLoader::makeInlineScript(
3080                                 ResourceLoader::makeConfigSetScript(
3081                                         [ 'wgPageParseReport' => $this->limitReportJSData ]
3082                                 )
3083                         );
3084                 }
3085
3086                 return self::combineWrappedStrings( $chunks );
3087         }
3088
3089         /**
3090          * Get the javascript config vars to include on this page
3091          *
3092          * @return array Array of javascript config vars
3093          * @since 1.23
3094          */
3095         public function getJsConfigVars() {
3096                 return $this->mJsConfigVars;
3097         }
3098
3099         /**
3100          * Add one or more variables to be set in mw.config in JavaScript
3101          *
3102          * @param string|array $keys Key or array of key/value pairs
3103          * @param mixed $value [optional] Value of the configuration variable
3104          */
3105         public function addJsConfigVars( $keys, $value = null ) {
3106                 if ( is_array( $keys ) ) {
3107                         foreach ( $keys as $key => $value ) {
3108                                 $this->mJsConfigVars[$key] = $value;
3109                         }
3110                         return;
3111                 }
3112
3113                 $this->mJsConfigVars[$keys] = $value;
3114         }
3115
3116         /**
3117          * Get an array containing the variables to be set in mw.config in JavaScript.
3118          *
3119          * Do not add things here which can be evaluated in ResourceLoaderStartUpModule
3120          * - in other words, page-independent/site-wide variables (without state).
3121          * You will only be adding bloat to the html page and causing page caches to
3122          * have to be purged on configuration changes.
3123          * @return array
3124          */
3125         public function getJSVars() {
3126                 global $wgContLang;
3127
3128                 $curRevisionId = 0;
3129                 $articleId = 0;
3130                 $canonicalSpecialPageName = false; # T23115
3131
3132                 $title = $this->getTitle();
3133                 $ns = $title->getNamespace();
3134                 $canonicalNamespace = MWNamespace::exists( $ns )
3135                         ? MWNamespace::getCanonicalName( $ns )
3136                         : $title->getNsText();
3137
3138                 $sk = $this->getSkin();
3139                 // Get the relevant title so that AJAX features can use the correct page name
3140                 // when making API requests from certain special pages (T36972).
3141                 $relevantTitle = $sk->getRelevantTitle();
3142                 $relevantUser = $sk->getRelevantUser();
3143
3144                 if ( $ns == NS_SPECIAL ) {
3145                         list( $canonicalSpecialPageName, /*...*/ ) =
3146                                 SpecialPageFactory::resolveAlias( $title->getDBkey() );
3147                 } elseif ( $this->canUseWikiPage() ) {
3148                         $wikiPage = $this->getWikiPage();
3149                         $curRevisionId = $wikiPage->getLatest();
3150                         $articleId = $wikiPage->getId();
3151                 }
3152
3153                 $lang = $title->getPageViewLanguage();
3154
3155                 // Pre-process information
3156                 $separatorTransTable = $lang->separatorTransformTable();
3157                 $separatorTransTable = $separatorTransTable ? $separatorTransTable : [];
3158                 $compactSeparatorTransTable = [
3159                         implode( "\t", array_keys( $separatorTransTable ) ),
3160                         implode( "\t", $separatorTransTable ),
3161                 ];
3162                 $digitTransTable = $lang->digitTransformTable();
3163                 $digitTransTable = $digitTransTable ? $digitTransTable : [];
3164                 $compactDigitTransTable = [
3165                         implode( "\t", array_keys( $digitTransTable ) ),
3166                         implode( "\t", $digitTransTable ),
3167                 ];
3168
3169                 $user = $this->getUser();
3170
3171                 $vars = [
3172                         'wgCanonicalNamespace' => $canonicalNamespace,
3173                         'wgCanonicalSpecialPageName' => $canonicalSpecialPageName,
3174                         'wgNamespaceNumber' => $title->getNamespace(),
3175                         'wgPageName' => $title->getPrefixedDBkey(),
3176                         'wgTitle' => $title->getText(),
3177                         'wgCurRevisionId' => $curRevisionId,
3178                         'wgRevisionId' => (int)$this->getRevisionId(),
3179                         'wgArticleId' => $articleId,
3180                         'wgIsArticle' => $this->isArticle(),
3181                         'wgIsRedirect' => $title->isRedirect(),
3182                         'wgAction' => Action::getActionName( $this->getContext() ),
3183                         'wgUserName' => $user->isAnon() ? null : $user->getName(),
3184                         'wgUserGroups' => $user->getEffectiveGroups(),
3185                         'wgCategories' => $this->getCategories(),
3186                         'wgBreakFrames' => $this->getFrameOptions() == 'DENY',
3187                         'wgPageContentLanguage' => $lang->getCode(),
3188                         'wgPageContentModel' => $title->getContentModel(),
3189                         'wgSeparatorTransformTable' => $compactSeparatorTransTable,
3190                         'wgDigitTransformTable' => $compactDigitTransTable,
3191                         'wgDefaultDateFormat' => $lang->getDefaultDateFormat(),
3192                         'wgMonthNames' => $lang->getMonthNamesArray(),
3193                         'wgMonthNamesShort' => $lang->getMonthAbbreviationsArray(),
3194                         'wgRelevantPageName' => $relevantTitle->getPrefixedDBkey(),
3195                         'wgRelevantArticleId' => $relevantTitle->getArticleID(),
3196                         'wgRequestId' => WebRequest::getRequestId(),
3197                 ];
3198
3199                 if ( $user->isLoggedIn() ) {
3200                         $vars['wgUserId'] = $user->getId();
3201                         $vars['wgUserEditCount'] = $user->getEditCount();
3202                         $userReg = $user->getRegistration();
3203                         $vars['wgUserRegistration'] = $userReg ? wfTimestamp( TS_UNIX, $userReg ) * 1000 : null;
3204                         // Get the revision ID of the oldest new message on the user's talk
3205                         // page. This can be used for constructing new message alerts on
3206                         // the client side.
3207                         $vars['wgUserNewMsgRevisionId'] = $user->getNewMessageRevisionId();
3208                 }
3209
3210                 if ( $wgContLang->hasVariants() ) {
3211                         $vars['wgUserVariant'] = $wgContLang->getPreferredVariant();
3212                 }
3213                 // Same test as SkinTemplate
3214                 $vars['wgIsProbablyEditable'] = $title->quickUserCan( 'edit', $user )
3215                         && ( $title->exists() || $title->quickUserCan( 'create', $user ) );
3216
3217                 $vars['wgRelevantPageIsProbablyEditable'] = $relevantTitle
3218                         && $relevantTitle->quickUserCan( 'edit', $user )
3219                         && ( $relevantTitle->exists() || $relevantTitle->quickUserCan( 'create', $user ) );
3220
3221                 foreach ( $title->getRestrictionTypes() as $type ) {
3222                         $vars['wgRestriction' . ucfirst( $type )] = $title->getRestrictions( $type );
3223                 }
3224
3225                 if ( $title->isMainPage() ) {
3226                         $vars['wgIsMainPage'] = true;
3227                 }
3228
3229                 if ( $this->mRedirectedFrom ) {
3230                         $vars['wgRedirectedFrom'] = $this->mRedirectedFrom->getPrefixedDBkey();
3231                 }
3232
3233                 if ( $relevantUser ) {
3234                         $vars['wgRelevantUserName'] = $relevantUser->getName();
3235                 }
3236
3237                 // Allow extensions to add their custom variables to the mw.config map.
3238                 // Use the 'ResourceLoaderGetConfigVars' hook if the variable is not
3239                 // page-dependant but site-wide (without state).
3240                 // Alternatively, you may want to use OutputPage->addJsConfigVars() instead.
3241                 Hooks::run( 'MakeGlobalVariablesScript', [ &$vars, $this ] );
3242
3243                 // Merge in variables from addJsConfigVars last
3244                 return array_merge( $vars, $this->getJsConfigVars() );
3245         }
3246
3247         /**
3248          * To make it harder for someone to slip a user a fake
3249          * user-JavaScript or user-CSS preview, a random token
3250          * is associated with the login session. If it's not
3251          * passed back with the preview request, we won't render
3252          * the code.
3253          *
3254          * @return bool
3255          */
3256         public function userCanPreview() {
3257                 $request = $this->getRequest();
3258                 if (
3259                         $request->getVal( 'action' ) !== 'submit' ||
3260                         !$request->getCheck( 'wpPreview' ) ||
3261                         !$request->wasPosted()
3262                 ) {
3263                         return false;
3264                 }
3265
3266                 $user = $this->getUser();
3267
3268                 if ( !$user->isLoggedIn() ) {
3269                         // Anons have predictable edit tokens
3270                         return false;
3271                 }
3272                 if ( !$user->matchEditToken( $request->getVal( 'wpEditToken' ) ) ) {
3273                         return false;
3274                 }
3275
3276                 $title = $this->getTitle();
3277                 if ( !$title->isJsSubpage() && !$title->isCssSubpage() ) {
3278                         return false;
3279                 }
3280                 if ( !$title->isSubpageOf( $user->getUserPage() ) ) {
3281                         // Don't execute another user's CSS or JS on preview (T85855)
3282                         return false;
3283                 }
3284
3285                 $errors = $title->getUserPermissionsErrors( 'edit', $user );
3286                 if ( count( $errors ) !== 0 ) {
3287                         return false;
3288                 }
3289
3290                 return true;
3291         }
3292
3293         /**
3294          * @return array Array in format "link name or number => 'link html'".
3295          */
3296         public function getHeadLinksArray() {
3297                 global $wgVersion;
3298
3299                 $tags = [];
3300                 $config = $this->getConfig();
3301
3302                 $canonicalUrl = $this->mCanonicalUrl;
3303
3304                 $tags['meta-generator'] = Html::element( 'meta', [
3305                         'name' => 'generator',
3306                         'content' => "MediaWiki $wgVersion",
3307                 ] );
3308
3309                 if ( $config->get( 'ReferrerPolicy' ) !== false ) {
3310                         $tags['meta-referrer'] = Html::element( 'meta', [
3311                                 'name' => 'referrer',
3312                                 'content' => $config->get( 'ReferrerPolicy' )
3313                         ] );
3314                 }
3315
3316                 $p = "{$this->mIndexPolicy},{$this->mFollowPolicy}";
3317                 if ( $p !== 'index,follow' ) {
3318                         // http://www.robotstxt.org/wc/meta-user.html
3319                         // Only show if it's different from the default robots policy
3320                         $tags['meta-robots'] = Html::element( 'meta', [
3321                                 'name' => 'robots',
3322                                 'content' => $p,
3323                         ] );
3324                 }
3325
3326                 foreach ( $this->mMetatags as $tag ) {
3327                         if ( strncasecmp( $tag[0], 'http:', 5 ) === 0 ) {
3328                                 $a = 'http-equiv';
3329                                 $tag[0] = substr( $tag[0], 5 );
3330                         } elseif ( strncasecmp( $tag[0], 'og:', 3 ) === 0 ) {
3331                                 $a = 'property';
3332                         } else {
3333                                 $a = 'name';
3334                         }
3335                         $tagName = "meta-{$tag[0]}";
3336                         if ( isset( $tags[$tagName] ) ) {
3337                                 $tagName .= $tag[1];
3338                         }
3339                         $tags[$tagName] = Html::element( 'meta',
3340                                 [
3341                                         $a => $tag[0],
3342                                         'content' => $tag[1]
3343                                 ]
3344                         );
3345                 }
3346
3347                 foreach ( $this->mLinktags as $tag ) {
3348                         $tags[] = Html::element( 'link', $tag );
3349                 }
3350
3351                 # Universal edit button
3352                 if ( $config->get( 'UniversalEditButton' ) && $this->isArticleRelated() ) {
3353                         $user = $this->getUser();
3354                         if ( $this->getTitle()->quickUserCan( 'edit', $user )
3355                                 && ( $this->getTitle()->exists() ||
3356                                         $this->getTitle()->quickUserCan( 'create', $user ) )
3357                         ) {
3358                                 // Original UniversalEditButton
3359                                 $msg = $this->msg( 'edit' )->text();
3360                                 $tags['universal-edit-button'] = Html::element( 'link', [
3361                                         'rel' => 'alternate',
3362                                         'type' => 'application/x-wiki',
3363                                         'title' => $msg,
3364                                         'href' => $this->getTitle()->getEditURL(),
3365                                 ] );
3366                                 // Alternate edit link
3367                                 $tags['alternative-edit'] = Html::element( 'link', [
3368                                         'rel' => 'edit',
3369                                         'title' => $msg,
3370                                         'href' => $this->getTitle()->getEditURL(),
3371                                 ] );
3372                         }
3373                 }
3374
3375                 # Generally the order of the favicon and apple-touch-icon links
3376                 # should not matter, but Konqueror (3.5.9 at least) incorrectly
3377                 # uses whichever one appears later in the HTML source. Make sure
3378                 # apple-touch-icon is specified first to avoid this.
3379                 if ( $config->get( 'AppleTouchIcon' ) !== false ) {
3380                         $tags['apple-touch-icon'] = Html::element( 'link', [
3381                                 'rel' => 'apple-touch-icon',
3382                                 'href' => $config->get( 'AppleTouchIcon' )
3383                         ] );
3384                 }
3385
3386                 if ( $config->get( 'Favicon' ) !== false ) {
3387                         $tags['favicon'] = Html::element( 'link', [
3388                                 'rel' => 'shortcut icon',
3389                                 'href' => $config->get( 'Favicon' )
3390                         ] );
3391                 }
3392
3393                 # OpenSearch description link
3394                 $tags['opensearch'] = Html::element( 'link', [
3395                         'rel' => 'search',
3396                         'type' => 'application/opensearchdescription+xml',
3397                         'href' => wfScript( 'opensearch_desc' ),
3398                         'title' => $this->msg( 'opensearch-desc' )->inContentLanguage()->text(),
3399                 ] );
3400
3401                 if ( $config->get( 'EnableAPI' ) ) {
3402                         # Real Simple Discovery link, provides auto-discovery information
3403                         # for the MediaWiki API (and potentially additional custom API
3404                         # support such as WordPress or Twitter-compatible APIs for a
3405                         # blogging extension, etc)
3406                         $tags['rsd'] = Html::element( 'link', [
3407                                 'rel' => 'EditURI',
3408                                 'type' => 'application/rsd+xml',
3409                                 // Output a protocol-relative URL here if $wgServer is protocol-relative.
3410                                 // Whether RSD accepts relative or protocol-relative URLs is completely
3411                                 // undocumented, though.
3412                                 'href' => wfExpandUrl( wfAppendQuery(
3413                                         wfScript( 'api' ),
3414                                         [ 'action' => 'rsd' ] ),
3415                                         PROTO_RELATIVE
3416                                 ),
3417                         ] );
3418                 }
3419
3420                 # Language variants
3421                 if ( !$config->get( 'DisableLangConversion' ) ) {
3422                         $lang = $this->getTitle()->getPageLanguage();
3423                         if ( $lang->hasVariants() ) {
3424                                 $variants = $lang->getVariants();
3425                                 foreach ( $variants as $variant ) {
3426                                         $tags["variant-$variant"] = Html::element( 'link', [
3427                                                 'rel' => 'alternate',
3428                                                 'hreflang' => wfBCP47( $variant ),
3429                                                 'href' => $this->getTitle()->getLocalURL(
3430                                                         [ 'variant' => $variant ] )
3431                                                 ]
3432                                         );
3433                                 }
3434                                 # x-default link per https://support.google.com/webmasters/answer/189077?hl=en
3435                                 $tags["variant-x-default"] = Html::element( 'link', [
3436                                         'rel' => 'alternate',
3437                                         'hreflang' => 'x-default',
3438                                         'href' => $this->getTitle()->getLocalURL() ] );
3439                         }
3440                 }
3441
3442                 # Copyright
3443                 if ( $this->copyrightUrl !== null ) {
3444                         $copyright = $this->copyrightUrl;
3445                 } else {
3446                         $copyright = '';
3447                         if ( $config->get( 'RightsPage' ) ) {
3448                                 $copy = Title::newFromText( $config->get( 'RightsPage' ) );
3449
3450                                 if ( $copy ) {
3451                                         $copyright = $copy->getLocalURL();
3452                                 }
3453                         }
3454
3455                         if ( !$copyright && $config->get( 'RightsUrl' ) ) {
3456                                 $copyright = $config->get( 'RightsUrl' );
3457                         }
3458                 }
3459
3460                 if ( $copyright ) {
3461                         $tags['copyright'] = Html::element( 'link', [
3462                                 'rel' => 'license',
3463                                 'href' => $copyright ]
3464                         );
3465                 }
3466
3467                 # Feeds
3468                 if ( $config->get( 'Feed' ) ) {
3469                         $feedLinks = [];
3470
3471                         foreach ( $this->getSyndicationLinks() as $format => $link ) {
3472                                 # Use the page name for the title.  In principle, this could
3473                                 # lead to issues with having the same name for different feeds
3474                                 # corresponding to the same page, but we can't avoid that at
3475                                 # this low a level.
3476
3477                                 $feedLinks[] = $this->feedLink(
3478                                         $format,
3479                                         $link,
3480                                         # Used messages: 'page-rss-feed' and 'page-atom-feed' (for an easier grep)
3481                                         $this->msg(
3482                                                 "page-{$format}-feed", $this->getTitle()->getPrefixedText()
3483                                         )->text()
3484                                 );
3485                         }
3486
3487                         # Recent changes feed should appear on every page (except recentchanges,
3488                         # that would be redundant). Put it after the per-page feed to avoid
3489                         # changing existing behavior. It's still available, probably via a
3490                         # menu in your browser. Some sites might have a different feed they'd
3491                         # like to promote instead of the RC feed (maybe like a "Recent New Articles"
3492                         # or "Breaking news" one). For this, we see if $wgOverrideSiteFeed is defined.
3493                         # If so, use it instead.
3494                         $sitename = $config->get( 'Sitename' );
3495                         if ( $config->get( 'OverrideSiteFeed' ) ) {
3496                                 foreach ( $config->get( 'OverrideSiteFeed' ) as $type => $feedUrl ) {
3497                                         // Note, this->feedLink escapes the url.
3498                                         $feedLinks[] = $this->feedLink(
3499                                                 $type,
3500                                                 $feedUrl,
3501                                                 $this->msg( "site-{$type}-feed", $sitename )->text()
3502                                         );
3503                                 }
3504                         } elseif ( !$this->getTitle()->isSpecial( 'Recentchanges' ) ) {
3505                                 $rctitle = SpecialPage::getTitleFor( 'Recentchanges' );
3506                                 foreach ( $config->get( 'AdvertisedFeedTypes' ) as $format ) {
3507                                         $feedLinks[] = $this->feedLink(
3508                                                 $format,
3509                                                 $rctitle->getLocalURL( [ 'feed' => $format ] ),
3510                                                 # For grep: 'site-rss-feed', 'site-atom-feed'
3511                                                 $this->msg( "site-{$format}-feed", $sitename )->text()
3512                                         );
3513                                 }
3514                         }
3515
3516                         # Allow extensions to change the list pf feeds. This hook is primarily for changing,
3517                         # manipulating or removing existing feed tags. If you want to add new feeds, you should
3518                         # use OutputPage::addFeedLink() instead.
3519                         Hooks::run( 'AfterBuildFeedLinks', [ &$feedLinks ] );
3520
3521                         $tags += $feedLinks;
3522                 }
3523
3524                 # Canonical URL
3525                 if ( $config->get( 'EnableCanonicalServerLink' ) ) {
3526                         if ( $canonicalUrl !== false ) {
3527                                 $canonicalUrl = wfExpandUrl( $canonicalUrl, PROTO_CANONICAL );
3528                         } else {
3529                                 if ( $this->isArticleRelated() ) {
3530                                         // This affects all requests where "setArticleRelated" is true. This is
3531                                         // typically all requests that show content (query title, curid, oldid, diff),
3532                                         // and all wikipage actions (edit, delete, purge, info, history etc.).
3533                                         // It does not apply to File pages and Special pages.
3534                                         // 'history' and 'info' actions address page metadata rather than the page
3535                                         // content itself, so they may not be canonicalized to the view page url.
3536                                         // TODO: this ought to be better encapsulated in the Action class.
3537                                         $action = Action::getActionName( $this->getContext() );
3538                                         if ( in_array( $action, [ 'history', 'info' ] ) ) {
3539                                                 $query = "action={$action}";
3540                                         } else {
3541                                                 $query = '';
3542                                         }
3543                                         $canonicalUrl = $this->getTitle()->getCanonicalURL( $query );
3544                                 } else {
3545                                         $reqUrl = $this->getRequest()->getRequestURL();
3546                                         $canonicalUrl = wfExpandUrl( $reqUrl, PROTO_CANONICAL );
3547                                 }
3548                         }
3549                 }
3550                 if ( $canonicalUrl !== false ) {
3551                         $tags[] = Html::element( 'link', [
3552                                 'rel' => 'canonical',
3553                                 'href' => $canonicalUrl
3554                         ] );
3555                 }
3556
3557                 return $tags;
3558         }
3559
3560         /**
3561          * Generate a "<link rel/>" for a feed.
3562          *
3563          * @param string $type Feed type
3564          * @param string $url URL to the feed
3565          * @param string $text Value of the "title" attribute
3566          * @return string HTML fragment
3567          */
3568         private function feedLink( $type, $url, $text ) {
3569                 return Html::element( 'link', [
3570                         'rel' => 'alternate',
3571                         'type' => "application/$type+xml",
3572                         'title' => $text,
3573                         'href' => $url ]
3574                 );
3575         }
3576
3577         /**
3578          * Add a local or specified stylesheet, with the given media options.
3579          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3580          *
3581          * @param string $style URL to the file
3582          * @param string $media To specify a media type, 'screen', 'printable', 'handheld' or any.
3583          * @param string $condition For IE conditional comments, specifying an IE version
3584          * @param string $dir Set to 'rtl' or 'ltr' for direction-specific sheets
3585          */
3586         public function addStyle( $style, $media = '', $condition = '', $dir = '' ) {
3587                 $options = [];
3588                 if ( $media ) {
3589                         $options['media'] = $media;
3590                 }
3591                 if ( $condition ) {
3592                         $options['condition'] = $condition;
3593                 }
3594                 if ( $dir ) {
3595                         $options['dir'] = $dir;
3596                 }
3597                 $this->styles[$style] = $options;
3598         }
3599
3600         /**
3601          * Adds inline CSS styles
3602          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3603          *
3604          * @param mixed $style_css Inline CSS
3605          * @param string $flip Set to 'flip' to flip the CSS if needed
3606          */
3607         public function addInlineStyle( $style_css, $flip = 'noflip' ) {
3608                 if ( $flip === 'flip' && $this->getLanguage()->isRTL() ) {
3609                         # If wanted, and the interface is right-to-left, flip the CSS
3610                         $style_css = CSSJanus::transform( $style_css, true, false );
3611                 }
3612                 $this->mInlineStyles .= Html::inlineStyle( $style_css );
3613         }
3614
3615         /**
3616          * Build exempt modules and legacy non-ResourceLoader styles.
3617          *
3618          * @return string|WrappedStringList HTML
3619          */
3620         protected function buildExemptModules() {
3621                 global $wgContLang;
3622
3623                 $chunks = [];
3624                 // Things that go after the ResourceLoaderDynamicStyles marker
3625                 $append = [];
3626
3627                 // Exempt 'user' styles module (may need 'excludepages' for live preview)
3628                 if ( $this->isUserCssPreview() ) {
3629                         $append[] = $this->makeResourceLoaderLink(
3630                                 'user.styles',
3631                                 ResourceLoaderModule::TYPE_STYLES,
3632                                 [ 'excludepage' => $this->getTitle()->getPrefixedDBkey() ]
3633                         );
3634
3635                         // Load the previewed CSS. Janus it if needed.
3636                         // User-supplied CSS is assumed to in the wiki's content language.
3637                         $previewedCSS = $this->getRequest()->getText( 'wpTextbox1' );
3638                         if ( $this->getLanguage()->getDir() !== $wgContLang->getDir() ) {
3639                                 $previewedCSS = CSSJanus::transform( $previewedCSS, true, false );
3640                         }
3641                         $append[] = Html::inlineStyle( $previewedCSS );
3642                 }
3643
3644                 // We want site, private and user styles to override dynamically added styles from
3645                 // general modules, but we want dynamically added styles to override statically added
3646                 // style modules. So the order has to be:
3647                 // - page style modules (formatted by ResourceLoaderClientHtml::getHeadHtml())
3648                 // - dynamically loaded styles (added by mw.loader before ResourceLoaderDynamicStyles)
3649                 // - ResourceLoaderDynamicStyles marker
3650                 // - site/private/user styles
3651
3652                 // Add legacy styles added through addStyle()/addInlineStyle() here
3653                 $chunks[] = implode( '', $this->buildCssLinksArray() ) . $this->mInlineStyles;
3654
3655                 $chunks[] = Html::element(
3656                         'meta',
3657                         [ 'name' => 'ResourceLoaderDynamicStyles', 'content' => '' ]
3658                 );
3659
3660                 $separateReq = [ 'site.styles', 'user.styles' ];
3661                 foreach ( $this->rlExemptStyleModules as $group => $moduleNames ) {
3662                         // Combinable modules
3663                         $chunks[] = $this->makeResourceLoaderLink(
3664                                 array_diff( $moduleNames, $separateReq ),
3665                                 ResourceLoaderModule::TYPE_STYLES
3666                         );
3667
3668                         foreach ( array_intersect( $moduleNames, $separateReq ) as $name ) {
3669                                 // These require their own dedicated request in order to support "@import"
3670                                 // syntax, which is incompatible with concatenation. (T147667, T37562)
3671                                 $chunks[] = $this->makeResourceLoaderLink( $name,
3672                                         ResourceLoaderModule::TYPE_STYLES
3673                                 );
3674                         }
3675                 }
3676
3677                 return self::combineWrappedStrings( array_merge( $chunks, $append ) );
3678         }
3679
3680         /**
3681          * @return array
3682          */
3683         public function buildCssLinksArray() {
3684                 $links = [];
3685
3686                 // Add any extension CSS
3687                 foreach ( $this->mExtStyles as $url ) {
3688                         $this->addStyle( $url );
3689                 }
3690                 $this->mExtStyles = [];
3691
3692                 foreach ( $this->styles as $file => $options ) {
3693                         $link = $this->styleLink( $file, $options );
3694                         if ( $link ) {
3695                                 $links[$file] = $link;
3696                         }
3697                 }
3698                 return $links;
3699         }
3700
3701         /**
3702          * Generate \<link\> tags for stylesheets
3703          *
3704          * @param string $style URL to the file
3705          * @param array $options Option, can contain 'condition', 'dir', 'media' keys
3706          * @return string HTML fragment
3707          */
3708         protected function styleLink( $style, array $options ) {
3709                 if ( isset( $options['dir'] ) ) {
3710                         if ( $this->getLanguage()->getDir() != $options['dir'] ) {
3711                                 return '';
3712                         }
3713                 }
3714
3715                 if ( isset( $options['media'] ) ) {
3716                         $media = self::transformCssMedia( $options['media'] );
3717                         if ( is_null( $media ) ) {
3718                                 return '';
3719                         }
3720                 } else {
3721                         $media = 'all';
3722                 }
3723
3724                 if ( substr( $style, 0, 1 ) == '/' ||
3725                         substr( $style, 0, 5 ) == 'http:' ||
3726                         substr( $style, 0, 6 ) == 'https:' ) {
3727                         $url = $style;
3728                 } else {
3729                         $config = $this->getConfig();
3730                         $url = $config->get( 'StylePath' ) . '/' . $style . '?' .
3731                                 $config->get( 'StyleVersion' );
3732                 }
3733
3734                 $link = Html::linkedStyle( $url, $media );
3735
3736                 if ( isset( $options['condition'] ) ) {
3737                         $condition = htmlspecialchars( $options['condition'] );
3738                         $link = "<!--[if $condition]>$link<![endif]-->";
3739                 }
3740                 return $link;
3741         }
3742
3743         /**
3744          * Transform path to web-accessible static resource.
3745          *
3746          * This is used to add a validation hash as query string.
3747          * This aids various behaviors:
3748          *
3749          * - Put long Cache-Control max-age headers on responses for improved
3750          *   cache performance.
3751          * - Get the correct version of a file as expected by the current page.
3752          * - Instantly get the updated version of a file after deployment.
3753          *
3754          * Avoid using this for urls included in HTML as otherwise clients may get different
3755          * versions of a resource when navigating the site depending on when the page was cached.
3756          * If changes to the url propagate, this is not a problem (e.g. if the url is in
3757          * an external stylesheet).
3758          *
3759          * @since 1.27
3760          * @param Config $config
3761          * @param string $path Path-absolute URL to file (from document root, must start with "/")
3762          * @return string URL
3763          */
3764         public static function transformResourcePath( Config $config, $path ) {
3765                 global $IP;
3766
3767                 $localDir = $IP;
3768                 $remotePathPrefix = $config->get( 'ResourceBasePath' );
3769                 if ( $remotePathPrefix === '' ) {
3770                         // The configured base path is required to be empty string for
3771                         // wikis in the domain root
3772                         $remotePath = '/';
3773                 } else {
3774                         $remotePath = $remotePathPrefix;
3775                 }
3776                 if ( strpos( $path, $remotePath ) !== 0 || substr( $path, 0, 2 ) === '//' ) {
3777                         // - Path is outside wgResourceBasePath, ignore.
3778                         // - Path is protocol-relative. Fixes T155310. Not supported by RelPath lib.
3779                         return $path;
3780                 }
3781                 // For files in resources, extensions/ or skins/, ResourceBasePath is preferred here.
3782                 // For other misc files in $IP, we'll fallback to that as well. There is, however, a fourth
3783                 // supported dir/path pair in the configuration (wgUploadDirectory, wgUploadPath)
3784                 // which is not expected to be in wgResourceBasePath on CDNs. (T155146)
3785                 $uploadPath = $config->get( 'UploadPath' );
3786                 if ( strpos( $path, $uploadPath ) === 0 ) {
3787                         $localDir = $config->get( 'UploadDirectory' );
3788                         $remotePathPrefix = $remotePath = $uploadPath;
3789                 }
3790
3791                 $path = RelPath\getRelativePath( $path, $remotePath );
3792                 return self::transformFilePath( $remotePathPrefix, $localDir, $path );
3793         }
3794
3795         /**
3796          * Utility method for transformResourceFilePath().
3797          *
3798          * Caller is responsible for ensuring the file exists. Emits a PHP warning otherwise.
3799          *
3800          * @since 1.27
3801          * @param string $remotePathPrefix URL path prefix that points to $localPath
3802          * @param string $localPath File directory exposed at $remotePath
3803          * @param string $file Path to target file relative to $localPath
3804          * @return string URL
3805          */
3806         public static function transformFilePath( $remotePathPrefix, $localPath, $file ) {
3807                 $hash = md5_file( "$localPath/$file" );
3808                 if ( $hash === false ) {
3809                         wfLogWarning( __METHOD__ . ": Failed to hash $localPath/$file" );
3810                         $hash = '';
3811                 }
3812                 return "$remotePathPrefix/$file?" . substr( $hash, 0, 5 );
3813         }
3814
3815         /**
3816          * Transform "media" attribute based on request parameters
3817          *
3818          * @param string $media Current value of the "media" attribute
3819          * @return string Modified value of the "media" attribute, or null to skip
3820          * this stylesheet
3821          */
3822         public static function transformCssMedia( $media ) {
3823                 global $wgRequest;
3824
3825                 // https://www.w3.org/TR/css3-mediaqueries/#syntax
3826                 $screenMediaQueryRegex = '/^(?:only\s+)?screen\b/i';
3827
3828                 // Switch in on-screen display for media testing
3829                 $switches = [
3830                         'printable' => 'print',
3831                         'handheld' => 'handheld',
3832                 ];
3833                 foreach ( $switches as $switch => $targetMedia ) {
3834                         if ( $wgRequest->getBool( $switch ) ) {
3835                                 if ( $media == $targetMedia ) {
3836                                         $media = '';
3837                                 } elseif ( preg_match( $screenMediaQueryRegex, $media ) === 1 ) {
3838                                         /* This regex will not attempt to understand a comma-separated media_query_list
3839                                          *
3840                                          * Example supported values for $media:
3841                                          * 'screen', 'only screen', 'screen and (min-width: 982px)' ),
3842                                          * Example NOT supported value for $media:
3843                                          * '3d-glasses, screen, print and resolution > 90dpi'
3844                                          *
3845                                          * If it's a print request, we never want any kind of screen stylesheets
3846                                          * If it's a handheld request (currently the only other choice with a switch),
3847                                          * we don't want simple 'screen' but we might want screen queries that
3848                                          * have a max-width or something, so we'll pass all others on and let the
3849                                          * client do the query.
3850                                          */
3851                                         if ( $targetMedia == 'print' || $media == 'screen' ) {
3852                                                 return null;
3853                                         }
3854                                 }
3855                         }
3856                 }
3857
3858                 return $media;
3859         }
3860
3861         /**
3862          * Add a wikitext-formatted message to the output.
3863          * This is equivalent to:
3864          *
3865          *    $wgOut->addWikiText( wfMessage( ... )->plain() )
3866          */
3867         public function addWikiMsg( /*...*/ ) {
3868                 $args = func_get_args();
3869                 $name = array_shift( $args );
3870                 $this->addWikiMsgArray( $name, $args );
3871         }
3872
3873         /**
3874          * Add a wikitext-formatted message to the output.
3875          * Like addWikiMsg() except the parameters are taken as an array
3876          * instead of a variable argument list.
3877          *
3878          * @param string $name
3879          * @param array $args
3880          */
3881         public function addWikiMsgArray( $name, $args ) {
3882                 $this->addHTML( $this->msg( $name, $args )->parseAsBlock() );
3883         }
3884
3885         /**
3886          * This function takes a number of message/argument specifications, wraps them in
3887          * some overall structure, and then parses the result and adds it to the output.
3888          *
3889          * In the $wrap, $1 is replaced with the first message, $2 with the second,
3890          * and so on. The subsequent arguments may be either
3891          * 1) strings, in which case they are message names, or
3892          * 2) arrays, in which case, within each array, the first element is the message
3893          *    name, and subsequent elements are the parameters to that message.
3894          *
3895          * Don't use this for messages that are not in the user's interface language.
3896          *
3897          * For example:
3898          *
3899          *    $wgOut->wrapWikiMsg( "<div class='error'>\n$1\n</div>", 'some-error' );
3900          *
3901          * Is equivalent to:
3902          *
3903          *    $wgOut->addWikiText( "<div class='error'>\n"
3904          *        . wfMessage( 'some-error' )->plain() . "\n</div>" );
3905          *
3906          * The newline after the opening div is needed in some wikitext. See T21226.
3907          *
3908          * @param string $wrap
3909          */
3910         public function wrapWikiMsg( $wrap /*, ...*/ ) {
3911                 $msgSpecs = func_get_args();
3912                 array_shift( $msgSpecs );
3913                 $msgSpecs = array_values( $msgSpecs );
3914                 $s = $wrap;
3915                 foreach ( $msgSpecs as $n => $spec ) {
3916                         if ( is_array( $spec ) ) {
3917                                 $args = $spec;
3918                                 $name = array_shift( $args );
3919                                 if ( isset( $args['options'] ) ) {
3920                                         unset( $args['options'] );
3921                                         wfDeprecated(
3922                                                 'Adding "options" to ' . __METHOD__ . ' is no longer supported',
3923                                                 '1.20'
3924                                         );
3925                                 }
3926                         } else {
3927                                 $args = [];
3928                                 $name = $spec;
3929                         }
3930                         $s = str_replace( '$' . ( $n + 1 ), $this->msg( $name, $args )->plain(), $s );
3931                 }
3932                 $this->addWikiText( $s );
3933         }
3934
3935         /**
3936          * Whether the output has a table of contents
3937          * @return bool
3938          * @since 1.22
3939          */
3940         public function isTOCEnabled() {
3941                 return $this->mEnableTOC;
3942         }
3943
3944         /**
3945          * Enables/disables section edit links, doesn't override __NOEDITSECTION__
3946          * @param bool $flag
3947          * @since 1.23
3948          */
3949         public function enableSectionEditLinks( $flag = true ) {
3950                 $this->mEnableSectionEditLinks = $flag;
3951         }
3952
3953         /**
3954          * @return bool
3955          * @since 1.23
3956          */
3957         public function sectionEditLinksEnabled() {
3958                 return $this->mEnableSectionEditLinks;
3959         }
3960
3961         /**
3962          * Helper function to setup the PHP implementation of OOUI to use in this request.
3963          *
3964          * @since 1.26
3965          * @param String $skinName The Skin name to determine the correct OOUI theme
3966          * @param String $dir Language direction
3967          */
3968         public static function setupOOUI( $skinName = 'default', $dir = 'ltr' ) {
3969                 $themes = ResourceLoaderOOUIModule::getSkinThemeMap();
3970                 $theme = isset( $themes[$skinName] ) ? $themes[$skinName] : $themes['default'];
3971                 // For example, 'OOUI\WikimediaUITheme'.
3972                 $themeClass = "OOUI\\{$theme}Theme";
3973                 OOUI\Theme::setSingleton( new $themeClass() );
3974                 OOUI\Element::setDefaultDir( $dir );
3975         }
3976
3977         /**
3978          * Add ResourceLoader module styles for OOUI and set up the PHP implementation of it for use with
3979          * MediaWiki and this OutputPage instance.
3980          *
3981          * @since 1.25
3982          */
3983         public function enableOOUI() {
3984                 self::setupOOUI(
3985                         strtolower( $this->getSkin()->getSkinName() ),
3986                         $this->getLanguage()->getDir()
3987                 );
3988                 $this->addModuleStyles( [
3989                         'oojs-ui-core.styles',
3990                         'oojs-ui.styles.indicators',
3991                         'oojs-ui.styles.textures',
3992                         'mediawiki.widgets.styles',
3993                         'oojs-ui.styles.icons-content',
3994                         'oojs-ui.styles.icons-alerts',
3995                         'oojs-ui.styles.icons-interactions',
3996                 ] );
3997         }
3998
3999         /**
4000          * Add Link headers for preloading the wiki's logo.
4001          *
4002          * @since 1.26
4003          */
4004         protected function addLogoPreloadLinkHeaders() {
4005                 $logo = ResourceLoaderSkinModule::getLogo( $this->getConfig() );
4006
4007                 $tags = [];
4008                 $logosPerDppx = [];
4009                 $logos = [];
4010
4011                 if ( !is_array( $logo ) ) {
4012                         // No media queries required if we only have one variant
4013                         $this->addLinkHeader( '<' . $logo . '>;rel=preload;as=image' );
4014                         return;
4015                 }
4016
4017                 foreach ( $logo as $dppx => $src ) {
4018                         // Keys are in this format: "1.5x"
4019                         $dppx = substr( $dppx, 0, -1 );
4020                         $logosPerDppx[$dppx] = $src;
4021                 }
4022
4023                 // Because PHP can't have floats as array keys
4024                 uksort( $logosPerDppx, function ( $a , $b ) {
4025                         $a = floatval( $a );
4026                         $b = floatval( $b );
4027
4028                         if ( $a == $b ) {
4029                                 return 0;
4030                         }
4031                         // Sort from smallest to largest (e.g. 1x, 1.5x, 2x)
4032                         return ( $a < $b ) ? -1 : 1;
4033                 } );
4034
4035                 foreach ( $logosPerDppx as $dppx => $src ) {
4036                         $logos[] = [ 'dppx' => $dppx, 'src' => $src ];
4037                 }
4038
4039                 $logosCount = count( $logos );
4040                 // Logic must match ResourceLoaderSkinModule:
4041                 // - 1x applies to resolution < 1.5dppx
4042                 // - 1.5x applies to resolution >= 1.5dppx && < 2dppx
4043                 // - 2x applies to resolution >= 2dppx
4044                 // Note that min-resolution and max-resolution are both inclusive.
4045                 for ( $i = 0; $i < $logosCount; $i++ ) {
4046                         if ( $i === 0 ) {
4047                                 // Smallest dppx
4048                                 // min-resolution is ">=" (larger than or equal to)
4049                                 // "not min-resolution" is essentially "<"
4050                                 $media_query = 'not all and (min-resolution: ' . $logos[ 1 ]['dppx'] . 'dppx)';
4051                         } elseif ( $i !== $logosCount - 1 ) {
4052                                 // In between
4053                                 // Media query expressions can only apply "not" to the entire expression
4054                                 // (e.g. can't express ">= 1.5 and not >= 2).
4055                                 // Workaround: Use <= 1.9999 in place of < 2.
4056                                 $upper_bound = floatval( $logos[ $i + 1 ]['dppx'] ) - 0.000001;
4057                                 $media_query = '(min-resolution: ' . $logos[ $i ]['dppx'] .
4058                                         'dppx) and (max-resolution: ' . $upper_bound . 'dppx)';
4059                         } else {
4060                                 // Largest dppx
4061                                 $media_query = '(min-resolution: ' . $logos[ $i ]['dppx'] . 'dppx)';
4062                         }
4063
4064                         $this->addLinkHeader(
4065                                 '<' . $logos[$i]['src'] . '>;rel=preload;as=image;media=' . $media_query
4066                         );
4067                 }
4068         }
4069 }