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 Additional <body> classes; there are also <body> classes from other sources */
 143         protected $mAdditionalBodyClasses = [];
 144
 145         /** @var array */
 146         protected $mModules = [];
 147
 148         /** @var array */
 149         protected $mModuleScripts = [];
 150
 151         /** @var array */
 152         protected $mModuleStyles = [];
 153
 154         /** @var ResourceLoader */
 155         protected $mResourceLoader;
 156
 157         /** @var ResourceLoaderClientHtml */
 158         private $rlClient;
 159
 160         /** @var ResourceLoaderContext */
 161         private $rlClientContext;
 162
 163         /** @var string */
 164         private $rlUserModuleState;
 165
 166         /** @var array */
 167         private $rlExemptStyleModules;
 168
 169         /** @var array */
 170         protected $mJsConfigVars = [];
 171
 172         /** @var array */
 173         protected $mTemplateIds = [];
 174
 175         /** @var array */
 176         protected $mImageTimeKeys = [];
 177
 178         /** @var string */
 179         public $mRedirectCode = '';
 180
 181         protected $mFeedLinksAppendQuery = null;
 182
 183         /** @var array
 184          * What level of 'untrustworthiness' is allowed in CSS/JS modules loaded on this page?
 185          * @see ResourceLoaderModule::$origin
 186          * ResourceLoaderModule::ORIGIN_ALL is assumed unless overridden;
 187          */
 188         protected $mAllowedModules = [
 189                 ResourceLoaderModule::TYPE_COMBINED => ResourceLoaderModule::ORIGIN_ALL,
 190         ];
 191
 192         /** @var bool Whether output is disabled.  If this is true, the 'output' method will do nothing. */
 193         protected $mDoNothing = false;
 194
 195         // Parser related.
 196
 197         /** @var int */
 198         protected $mContainsNewMagic = 0;
 199
 200         /**
 201          * lazy initialised, use parserOptions()
 202          * @var ParserOptions
 203          */
 204         protected $mParserOptions = null;
 205
 206         /**
 207          * Handles the Atom / RSS links.
 208          * We probably only support Atom in 2011.
 209          * @see $wgAdvertisedFeedTypes
 210          */
 211         private $mFeedLinks = [];
 212
 213         // Gwicke work on squid caching? Roughly from 2003.
 214         protected $mEnableClientCache = true;
 215
 216         /** @var bool Flag if output should only contain the body of the article. */
 217         private $mArticleBodyOnly = false;
 218
 219         /** @var bool */
 220         protected $mNewSectionLink = false;
 221
 222         /** @var bool */
 223         protected $mHideNewSectionLink = false;
 224
 225         /**
 226          * @var bool Comes from the parser. This was probably made to load CSS/JS
 227          * only if we had "<gallery>". Used directly in CategoryPage.php.
 228          * Looks like ResourceLoader can replace this.
 229          */
 230         public $mNoGallery = false;
 231
 232         /** @var string */
 233         private $mPageTitleActionText = '';
 234
 235         /** @var int Cache stuff. Looks like mEnableClientCache */
 236         protected $mCdnMaxage = 0;
 237         /** @var int Upper limit on mCdnMaxage */
 238         protected $mCdnMaxageLimit = INF;
 239
 240         /**
 241          * @var bool Controls if anti-clickjacking / frame-breaking headers will
 242          * be sent. This should be done for pages where edit actions are possible.
 243          * Setters: $this->preventClickjacking() and $this->allowClickjacking().
 244          */
 245         protected $mPreventClickjacking = true;
 246
 247         /** @var int To include the variable {{REVISIONID}} */
 248         private $mRevisionId = null;
 249
 250         /** @var string */
 251         private $mRevisionTimestamp = null;
 252
 253         /** @var array */
 254         protected $mFileVersion = null;
 255
 256         /**
 257          * @var array An array of stylesheet filenames (relative from skins path),
 258          * with options for CSS media, IE conditions, and RTL/LTR direction.
 259          * For internal use; add settings in the skin via $this->addStyle()
 260          *
 261          * Style again! This seems like a code duplication since we already have
 262          * mStyles. This is what makes Open Source amazing.
 263          */
 264         protected $styles = [];
 265
 266         private $mIndexPolicy = 'index';
 267         private $mFollowPolicy = 'follow';
 268         private $mVaryHeader = [
 269                 'Accept-Encoding' => [ 'match=gzip' ],
 270         ];
 271
 272         /**
 273          * If the current page was reached through a redirect, $mRedirectedFrom contains the Title
 274          * of the redirect.
 275          *
 276          * @var Title
 277          */
 278         private $mRedirectedFrom = null;
 279
 280         /**
 281          * Additional key => value data
 282          */
 283         private $mProperties = [];
 284
 285         /**
 286          * @var string|null ResourceLoader target for load.php links. If null, will be omitted
 287          */
 288         private $mTarget = null;
 289
 290         /**
 291          * @var bool Whether parser output contains a table of contents
 292          */
 293         private $mEnableTOC = false;
 294
 295         /**
 296          * @var bool Whether parser output should contain section edit links
 297          */
 298         private $mEnableSectionEditLinks = true;
 299
 300         /**
 301          * @var string|null The URL to send in a <link> element with rel=license
 302          */
 303         private $copyrightUrl;
 304
 305         /** @var array Profiling data */
 306         private $limitReportJSData = [];
 307
 308         /**
 309          * Link: header contents
 310          */
 311         private $mLinkHeader = [];
 312
 313         /**
 314          * Constructor for OutputPage. This should not be called directly.
 315          * Instead a new RequestContext should be created and it will implicitly create
 316          * a OutputPage tied to that context.
 317          * @param IContextSource $context
 318          */
 319         function __construct( IContextSource $context ) {
 320                 $this->setContext( $context );
 321         }
 322
 323         /**
 324          * Redirect to $url rather than displaying the normal page
 325          *
 326          * @param string $url URL
 327          * @param string $responsecode HTTP status code
 328          */
 329         public function redirect( $url, $responsecode = '302' ) {
 330                 # Strip newlines as a paranoia check for header injection in PHP<5.1.2
 331                 $this->mRedirect = str_replace( "\n", '', $url );
 332                 $this->mRedirectCode = $responsecode;
 333         }
 334
 335         /**
 336          * Get the URL to redirect to, or an empty string if not redirect URL set
 337          *
 338          * @return string
 339          */
 340         public function getRedirect() {
 341                 return $this->mRedirect;
 342         }
 343
 344         /**
 345          * Set the copyright URL to send with the output.
 346          * Empty string to omit, null to reset.
 347          *
 348          * @since 1.26
 349          *
 350          * @param string|null $url
 351          */
 352         public function setCopyrightUrl( $url ) {
 353                 $this->copyrightUrl = $url;
 354         }
 355
 356         /**
 357          * Set the HTTP status code to send with the output.
 358          *
 359          * @param int $statusCode
 360          */
 361         public function setStatusCode( $statusCode ) {
 362                 $this->mStatusCode = $statusCode;
 363         }
 364
 365         /**
 366          * Add a new "<meta>" tag
 367          * To add an http-equiv meta tag, precede the name with "http:"
 368          *
 369          * @param string $name Tag name
 370          * @param string $val Tag value
 371          */
 372         function addMeta( $name, $val ) {
 373                 array_push( $this->mMetatags, [ $name, $val ] );
 374         }
 375
 376         /**
 377          * Returns the current <meta> tags
 378          *
 379          * @since 1.25
 380          * @return array
 381          */
 382         public function getMetaTags() {
 383                 return $this->mMetatags;
 384         }
 385
 386         /**
 387          * Add a new \<link\> tag to the page header.
 388          *
 389          * Note: use setCanonicalUrl() for rel=canonical.
 390          *
 391          * @param array $linkarr Associative array of attributes.
 392          */
 393         function addLink( array $linkarr ) {
 394                 array_push( $this->mLinktags, $linkarr );
 395         }
 396
 397         /**
 398          * Returns the current <link> tags
 399          *
 400          * @since 1.25
 401          * @return array
 402          */
 403         public function getLinkTags() {
 404                 return $this->mLinktags;
 405         }
 406
 407         /**
 408          * Add a new \<link\> with "rel" attribute set to "meta"
 409          *
 410          * @param array $linkarr Associative array mapping attribute names to their
 411          *                 values, both keys and values will be escaped, and the
 412          *                 "rel" attribute will be automatically added
 413          */
 414         function addMetadataLink( array $linkarr ) {
 415                 $linkarr['rel'] = $this->getMetadataAttribute();
 416                 $this->addLink( $linkarr );
 417         }
 418
 419         /**
 420          * Set the URL to be used for the <link rel=canonical>. This should be used
 421          * in preference to addLink(), to avoid duplicate link tags.
 422          * @param string $url
 423          */
 424         function setCanonicalUrl( $url ) {
 425                 $this->mCanonicalUrl = $url;
 426         }
 427
 428         /**
 429          * Returns the URL to be used for the <link rel=canonical> if
 430          * one is set.
 431          *
 432          * @since 1.25
 433          * @return bool|string
 434          */
 435         public function getCanonicalUrl() {
 436                 return $this->mCanonicalUrl;
 437         }
 438
 439         /**
 440          * Get the value of the "rel" attribute for metadata links
 441          *
 442          * @return string
 443          */
 444         public function getMetadataAttribute() {
 445                 # note: buggy CC software only reads first "meta" link
 446                 static $haveMeta = false;
 447                 if ( $haveMeta ) {
 448                         return 'alternate meta';
 449                 } else {
 450                         $haveMeta = true;
 451                         return 'meta';
 452                 }
 453         }
 454
 455         /**
 456          * Add raw HTML to the list of scripts (including \<script\> tag, etc.)
 457          * Internal use only. Use OutputPage::addModules() or OutputPage::addJsConfigVars()
 458          * if possible.
 459          *
 460          * @param string $script Raw HTML
 461          */
 462         function addScript( $script ) {
 463                 $this->mScripts .= $script;
 464         }
 465
 466         /**
 467          * Register and add a stylesheet from an extension directory.
 468          *
 469          * @deprecated since 1.27 use addModuleStyles() or addStyle() instead
 470          * @param string $url Path to sheet.  Provide either a full url (beginning
 471          *             with 'http', etc) or a relative path from the document root
 472          *             (beginning with '/').  Otherwise it behaves identically to
 473          *             addStyle() and draws from the /skins folder.
 474          */
 475         public function addExtensionStyle( $url ) {
 476                 wfDeprecated( __METHOD__, '1.27' );
 477                 array_push( $this->mExtStyles, $url );
 478         }
 479
 480         /**
 481          * Get all styles added by extensions
 482          *
 483          * @deprecated since 1.27
 484          * @return array
 485          */
 486         function getExtStyle() {
 487                 wfDeprecated( __METHOD__, '1.27' );
 488                 return $this->mExtStyles;
 489         }
 490
 491         /**
 492          * Add a JavaScript file out of skins/common, or a given relative path.
 493          * Internal use only. Use OutputPage::addModules() if possible.
 494          *
 495          * @param string $file Filename in skins/common or complete on-server path
 496          *              (/foo/bar.js)
 497          * @param string $version Style version of the file. Defaults to $wgStyleVersion
 498          */
 499         public function addScriptFile( $file, $version = null ) {
 500                 // See if $file parameter is an absolute URL or begins with a slash
 501                 if ( substr( $file, 0, 1 ) == '/' || preg_match( '#^[a-z]*://#i', $file ) ) {
 502                         $path = $file;
 503                 } else {
 504                         $path = $this->getConfig()->get( 'StylePath' ) . "/common/{$file}";
 505                 }
 506                 if ( is_null( $version ) ) {
 507                         $version = $this->getConfig()->get( 'StyleVersion' );
 508                 }
 509                 $this->addScript( Html::linkedScript( wfAppendQuery( $path, $version ) ) );
 510         }
 511
 512         /**
 513          * Add a self-contained script tag with the given contents
 514          * Internal use only. Use OutputPage::addModules() if possible.
 515          *
 516          * @param string $script JavaScript text, no script tags
 517          */
 518         public function addInlineScript( $script ) {
 519                 $this->mScripts .= Html::inlineScript( $script );
 520         }
 521
 522         /**
 523          * Filter an array of modules to remove insufficiently trustworthy members, and modules
 524          * which are no longer registered (eg a page is cached before an extension is disabled)
 525          * @param array $modules
 526          * @param string|null $position If not null, only return modules with this position
 527          * @param string $type
 528          * @return array
 529          */
 530         protected function filterModules( array $modules, $position = null,
 531                 $type = ResourceLoaderModule::TYPE_COMBINED
 532         ) {
 533                 $resourceLoader = $this->getResourceLoader();
 534                 $filteredModules = [];
 535                 foreach ( $modules as $val ) {
 536                         $module = $resourceLoader->getModule( $val );
 537                         if ( $module instanceof ResourceLoaderModule
 538                                 && $module->getOrigin() <= $this->getAllowedModules( $type )
 539                                 && ( is_null( $position ) || $module->getPosition() == $position )
 540                         ) {
 541                                 if ( $this->mTarget && !in_array( $this->mTarget, $module->getTargets() ) ) {
 542                                         $this->warnModuleTargetFilter( $module->getName() );
 543                                         continue;
 544                                 }
 545                                 $filteredModules[] = $val;
 546                         }
 547                 }
 548                 return $filteredModules;
 549         }
 550
 551         private function warnModuleTargetFilter( $moduleName ) {
 552                 static $warnings = [];
 553                 if ( isset( $warnings[$this->mTarget][$moduleName] ) ) {
 554                         return;
 555                 }
 556                 $warnings[$this->mTarget][$moduleName] = true;
 557                 $this->getResourceLoader()->getLogger()->debug(
 558                         'Module "{module}" not loadable on target "{target}".',
 559                         [
 560                                 'module' => $moduleName,
 561                                 'target' => $this->mTarget,
 562                         ]
 563                 );
 564         }
 565
 566         /**
 567          * Get the list of modules to include on this page
 568          *
 569          * @param bool $filter Whether to filter out insufficiently trustworthy modules
 570          * @param string|null $position If not null, only return modules with this position
 571          * @param string $param
 572          * @param string $type
 573          * @return array Array of module names
 574          */
 575         public function getModules( $filter = false, $position = null, $param = 'mModules',
 576                 $type = ResourceLoaderModule::TYPE_COMBINED
 577         ) {
 578                 $modules = array_values( array_unique( $this->$param ) );
 579                 return $filter
 580                         ? $this->filterModules( $modules, $position, $type )
 581                         : $modules;
 582         }
 583
 584         /**
 585          * Add one or more modules recognized by ResourceLoader. Modules added
 586          * through this function will be loaded by ResourceLoader when the
 587          * page loads.
 588          *
 589          * @param string|array $modules Module name (string) or array of module names
 590          */
 591         public function addModules( $modules ) {
 592                 $this->mModules = array_merge( $this->mModules, (array)$modules );
 593         }
 594
 595         /**
 596          * Get the list of module JS to include on this page
 597          *
 598          * @param bool $filter
 599          * @param string|null $position
 600          * @return array Array of module names
 601          */
 602         public function getModuleScripts( $filter = false, $position = null ) {
 603                 return $this->getModules( $filter, $position, 'mModuleScripts',
 604                         ResourceLoaderModule::TYPE_SCRIPTS
 605                 );
 606         }
 607
 608         /**
 609          * Add only JS of one or more modules recognized by ResourceLoader. Module
 610          * scripts added through this function will be loaded by ResourceLoader when
 611          * the page loads.
 612          *
 613          * @param string|array $modules Module name (string) or array of module names
 614          */
 615         public function addModuleScripts( $modules ) {
 616                 $this->mModuleScripts = array_merge( $this->mModuleScripts, (array)$modules );
 617         }
 618
 619         /**
 620          * Get the list of module CSS to include on this page
 621          *
 622          * @param bool $filter
 623          * @param string|null $position
 624          * @return array Array of module names
 625          */
 626         public function getModuleStyles( $filter = false, $position = null ) {
 627                 return $this->getModules( $filter, $position, 'mModuleStyles',
 628                         ResourceLoaderModule::TYPE_STYLES
 629                 );
 630         }
 631
 632         /**
 633          * Add only CSS of one or more modules recognized by ResourceLoader.
 634          *
 635          * Module styles added through this function will be added using standard link CSS
 636          * tags, rather than as a combined Javascript and CSS package. Thus, they will
 637          * load when JavaScript is disabled (unless CSS also happens to be disabled).
 638          *
 639          * @param string|array $modules Module name (string) or array of module names
 640          */
 641         public function addModuleStyles( $modules ) {
 642                 $this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
 643         }
 644
 645         /**
 646          * @return null|string ResourceLoader target
 647          */
 648         public function getTarget() {
 649                 return $this->mTarget;
 650         }
 651
 652         /**
 653          * Sets ResourceLoader target for load.php links. If null, will be omitted
 654          *
 655          * @param string|null $target
 656          */
 657         public function setTarget( $target ) {
 658                 $this->mTarget = $target;
 659         }
 660
 661         /**
 662          * Get an array of head items
 663          *
 664          * @return array
 665          */
 666         function getHeadItemsArray() {
 667                 return $this->mHeadItems;
 668         }
 669
 670         /**
 671          * Add or replace a head item to the output
 672          *
 673          * Whenever possible, use more specific options like ResourceLoader modules,
 674          * OutputPage::addLink(), OutputPage::addMetaLink() and OutputPage::addFeedLink()
 675          * Fallback options for those are: OutputPage::addStyle, OutputPage::addScript(),
 676          * OutputPage::addInlineScript() and OutputPage::addInlineStyle()
 677          * This would be your very LAST fallback.
 678          *
 679          * @param string $name Item name
 680          * @param string $value Raw HTML
 681          */
 682         public function addHeadItem( $name, $value ) {
 683                 $this->mHeadItems[$name] = $value;
 684         }
 685
 686         /**
 687          * Add one or more head items to the output
 688          *
 689          * @since 1.28
 690          * @param string|string[] $values Raw HTML
 691          */
 692         public function addHeadItems( $values ) {
 693                 $this->mHeadItems = array_merge( $this->mHeadItems, (array)$values );
 694         }
 695
 696         /**
 697          * Check if the header item $name is already set
 698          *
 699          * @param string $name Item name
 700          * @return bool
 701          */
 702         public function hasHeadItem( $name ) {
 703                 return isset( $this->mHeadItems[$name] );
 704         }
 705
 706         /**
 707          * Add a class to the <body> element
 708          *
 709          * @since 1.30
 710          * @param string|string[] $classes One or more classes to add
 711          */
 712         public function addBodyClasses( $classes ) {
 713                 $this->mAdditionalBodyClasses = array_merge( $this->mAdditionalBodyClasses, (array)$classes );
 714         }
 715
 716         /**
 717          * @deprecated since 1.28 Obsolete - wgUseETag experiment was removed.
 718          * @param string $tag
 719          */
 720         public function setETag( $tag ) {
 721         }
 722
 723         /**
 724          * Set whether the output should only contain the body of the article,
 725          * without any skin, sidebar, etc.
 726          * Used e.g. when calling with "action=render".
 727          *
 728          * @param bool $only Whether to output only the body of the article
 729          */
 730         public function setArticleBodyOnly( $only ) {
 731                 $this->mArticleBodyOnly = $only;
 732         }
 733
 734         /**
 735          * Return whether the output will contain only the body of the article
 736          *
 737          * @return bool
 738          */
 739         public function getArticleBodyOnly() {
 740                 return $this->mArticleBodyOnly;
 741         }
 742
 743         /**
 744          * Set an additional output property
 745          * @since 1.21
 746          *
 747          * @param string $name
 748          * @param mixed $value
 749          */
 750         public function setProperty( $name, $value ) {
 751                 $this->mProperties[$name] = $value;
 752         }
 753
 754         /**
 755          * Get an additional output property
 756          * @since 1.21
 757          *
 758          * @param string $name
 759          * @return mixed Property value or null if not found
 760          */
 761         public function getProperty( $name ) {
 762                 if ( isset( $this->mProperties[$name] ) ) {
 763                         return $this->mProperties[$name];
 764                 } else {
 765                         return null;
 766                 }
 767         }
 768
 769         /**
 770          * checkLastModified tells the client to use the client-cached page if
 771          * possible. If successful, the OutputPage is disabled so that
 772          * any future call to OutputPage->output() have no effect.
 773          *
 774          * Side effect: sets mLastModified for Last-Modified header
 775          *
 776          * @param string $timestamp
 777          *
 778          * @return bool True if cache-ok headers was sent.
 779          */
 780         public function checkLastModified( $timestamp ) {
 781                 if ( !$timestamp || $timestamp == '19700101000000' ) {
 782                         wfDebug( __METHOD__ . ": CACHE DISABLED, NO TIMESTAMP\n" );
 783                         return false;
 784                 }
 785                 $config = $this->getConfig();
 786                 if ( !$config->get( 'CachePages' ) ) {
 787                         wfDebug( __METHOD__ . ": CACHE DISABLED\n" );
 788                         return false;
 789                 }
 790
 791                 $timestamp = wfTimestamp( TS_MW, $timestamp );
 792                 $modifiedTimes = [
 793                         'page' => $timestamp,
 794                         'user' => $this->getUser()->getTouched(),
 795                         'epoch' => $config->get( 'CacheEpoch' )
 796                 ];
 797                 if ( $config->get( 'UseSquid' ) ) {
 798                         // T46570: the core page itself may not change, but resources might
 799                         $modifiedTimes['sepoch'] = wfTimestamp( TS_MW, time() - $config->get( 'SquidMaxage' ) );
 800                 }
 801                 Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this ] );
 802
 803                 $maxModified = max( $modifiedTimes );
 804                 $this->mLastModified = wfTimestamp( TS_RFC2822, $maxModified );
 805
 806                 $clientHeader = $this->getRequest()->getHeader( 'If-Modified-Since' );
 807                 if ( $clientHeader === false ) {
 808                         wfDebug( __METHOD__ . ": client did not send If-Modified-Since header", 'private' );
 809                         return false;
 810                 }
 811
 812                 # IE sends sizes after the date like this:
 813                 # Wed, 20 Aug 2003 06:51:19 GMT; length=5202
 814                 # this breaks strtotime().
 815                 $clientHeader = preg_replace( '/;.*$/', '', $clientHeader );
 816
 817                 MediaWiki\suppressWarnings(); // E_STRICT system time bitching
 818                 $clientHeaderTime = strtotime( $clientHeader );
 819                 MediaWiki\restoreWarnings();
 820                 if ( !$clientHeaderTime ) {
 821                         wfDebug( __METHOD__
 822                                 . ": unable to parse the client's If-Modified-Since header: $clientHeader\n" );
 823                         return false;
 824                 }
 825                 $clientHeaderTime = wfTimestamp( TS_MW, $clientHeaderTime );
 826
 827                 # Make debug info
 828                 $info = '';
 829                 foreach ( $modifiedTimes as $name => $value ) {
 830                         if ( $info !== '' ) {
 831                                 $info .= ', ';
 832                         }
 833                         $info .= "$name=" . wfTimestamp( TS_ISO_8601, $value );
 834                 }
 835
 836                 wfDebug( __METHOD__ . ": client sent If-Modified-Since: " .
 837                         wfTimestamp( TS_ISO_8601, $clientHeaderTime ), 'private' );
 838                 wfDebug( __METHOD__ . ": effective Last-Modified: " .
 839                         wfTimestamp( TS_ISO_8601, $maxModified ), 'private' );
 840                 if ( $clientHeaderTime < $maxModified ) {
 841                         wfDebug( __METHOD__ . ": STALE, $info", 'private' );
 842                         return false;
 843                 }
 844
 845                 # Not modified
 846                 # Give a 304 Not Modified response code and disable body output
 847                 wfDebug( __METHOD__ . ": NOT MODIFIED, $info", 'private' );
 848                 ini_set( 'zlib.output_compression', 0 );
 849                 $this->getRequest()->response()->statusHeader( 304 );
 850                 $this->sendCacheControl();
 851                 $this->disable();
 852
 853                 // Don't output a compressed blob when using ob_gzhandler;
 854                 // it's technically against HTTP spec and seems to confuse
 855                 // Firefox when the response gets split over two packets.
 856                 wfClearOutputBuffers();
 857
 858                 return true;
 859         }
 860
 861         /**
 862          * Override the last modified timestamp
 863          *
 864          * @param string $timestamp New timestamp, in a format readable by
 865          *        wfTimestamp()
 866          */
 867         public function setLastModified( $timestamp ) {
 868                 $this->mLastModified = wfTimestamp( TS_RFC2822, $timestamp );
 869         }
 870
 871         /**
 872          * Set the robot policy for the page: <http://www.robotstxt.org/meta.html>
 873          *
 874          * @param string $policy The literal string to output as the contents of
 875          *   the meta tag.  Will be parsed according to the spec and output in
 876          *   standardized form.
 877          * @return null
 878          */
 879         public function setRobotPolicy( $policy ) {
 880                 $policy = Article::formatRobotPolicy( $policy );
 881
 882                 if ( isset( $policy['index'] ) ) {
 883                         $this->setIndexPolicy( $policy['index'] );
 884                 }
 885                 if ( isset( $policy['follow'] ) ) {
 886                         $this->setFollowPolicy( $policy['follow'] );
 887                 }
 888         }
 889
 890         /**
 891          * Set the index policy for the page, but leave the follow policy un-
 892          * touched.
 893          *
 894          * @param string $policy Either 'index' or 'noindex'.
 895          * @return null
 896          */
 897         public function setIndexPolicy( $policy ) {
 898                 $policy = trim( $policy );
 899                 if ( in_array( $policy, [ 'index', 'noindex' ] ) ) {
 900                         $this->mIndexPolicy = $policy;
 901                 }
 902         }
 903
 904         /**
 905          * Set the follow policy for the page, but leave the index policy un-
 906          * touched.
 907          *
 908          * @param string $policy Either 'follow' or 'nofollow'.
 909          * @return null
 910          */
 911         public function setFollowPolicy( $policy ) {
 912                 $policy = trim( $policy );
 913                 if ( in_array( $policy, [ 'follow', 'nofollow' ] ) ) {
 914                         $this->mFollowPolicy = $policy;
 915                 }
 916         }
 917
 918         /**
 919          * Set the new value of the "action text", this will be added to the
 920          * "HTML title", separated from it with " - ".
 921          *
 922          * @param string $text New value of the "action text"
 923          */
 924         public function setPageTitleActionText( $text ) {
 925                 $this->mPageTitleActionText = $text;
 926         }
 927
 928         /**
 929          * Get the value of the "action text"
 930          *
 931          * @return string
 932          */
 933         public function getPageTitleActionText() {
 934                 return $this->mPageTitleActionText;
 935         }
 936
 937         /**
 938          * "HTML title" means the contents of "<title>".
 939          * It is stored as plain, unescaped text and will be run through htmlspecialchars in the skin file.
 940          *
 941          * @param string|Message $name
 942          */
 943         public function setHTMLTitle( $name ) {
 944                 if ( $name instanceof Message ) {
 945                         $this->mHTMLtitle = $name->setContext( $this->getContext() )->text();
 946                 } else {
 947                         $this->mHTMLtitle = $name;
 948                 }
 949         }
 950
 951         /**
 952          * Return the "HTML title", i.e. the content of the "<title>" tag.
 953          *
 954          * @return string
 955          */
 956         public function getHTMLTitle() {
 957                 return $this->mHTMLtitle;
 958         }
 959
 960         /**
 961          * Set $mRedirectedFrom, the Title of the page which redirected us to the current page.
 962          *
 963          * @param Title $t
 964          */
 965         public function setRedirectedFrom( $t ) {
 966                 $this->mRedirectedFrom = $t;
 967         }
 968
 969         /**
 970          * "Page title" means the contents of \<h1\>. It is stored as a valid HTML
 971          * fragment. This function allows good tags like \<sup\> in the \<h1\> tag,
 972          * but not bad tags like \<script\>. This function automatically sets
 973          * \<title\> to the same content as \<h1\> but with all tags removed. Bad
 974          * tags that were escaped in \<h1\> will still be escaped in \<title\>, and
 975          * good tags like \<i\> will be dropped entirely.
 976          *
 977          * @param string|Message $name
 978          */
 979         public function setPageTitle( $name ) {
 980                 if ( $name instanceof Message ) {
 981                         $name = $name->setContext( $this->getContext() )->text();
 982                 }
 983
 984                 # change "<script>foo&bar</script>" to "&lt;script&gt;foo&amp;bar&lt;/script&gt;"
 985                 # but leave "<i>foobar</i>" alone
 986                 $nameWithTags = Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $name ) );
 987                 $this->mPagetitle = $nameWithTags;
 988
 989                 # change "<i>foo&amp;bar</i>" to "foo&bar"
 990                 $this->setHTMLTitle(
 991                         $this->msg( 'pagetitle' )->rawParams( Sanitizer::stripAllTags( $nameWithTags ) )
 992                                 ->inContentLanguage()
 993                 );
 994         }
 995
 996         /**
 997          * Return the "page title", i.e. the content of the \<h1\> tag.
 998          *
 999          * @return string
1000          */
1001         public function getPageTitle() {
1002                 return $this->mPagetitle;
1003         }
1004
1005         /**
1006          * Set the Title object to use
1007          *
1008          * @param Title $t
1009          */
1010         public function setTitle( Title $t ) {
1011                 $this->getContext()->setTitle( $t );
1012         }
1013
1014         /**
1015          * Replace the subtitle with $str
1016          *
1017          * @param string|Message $str New value of the subtitle. String should be safe HTML.
1018          */
1019         public function setSubtitle( $str ) {
1020                 $this->clearSubtitle();
1021                 $this->addSubtitle( $str );
1022         }
1023
1024         /**
1025          * Add $str to the subtitle
1026          *
1027          * @param string|Message $str String or Message to add to the subtitle. String should be safe HTML.
1028          */
1029         public function addSubtitle( $str ) {
1030                 if ( $str instanceof Message ) {
1031                         $this->mSubtitle[] = $str->setContext( $this->getContext() )->parse();
1032                 } else {
1033                         $this->mSubtitle[] = $str;
1034                 }
1035         }
1036
1037         /**
1038          * Build message object for a subtitle containing a backlink to a page
1039          *
1040          * @param Title $title Title to link to
1041          * @param array $query Array of additional parameters to include in the link
1042          * @return Message
1043          * @since 1.25
1044          */
1045         public static function buildBacklinkSubtitle( Title $title, $query = [] ) {
1046                 if ( $title->isRedirect() ) {
1047                         $query['redirect'] = 'no';
1048                 }
1049                 $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1050                 return wfMessage( 'backlinksubtitle' )
1051                         ->rawParams( $linkRenderer->makeLink( $title, null, [], $query ) );
1052         }
1053
1054         /**
1055          * Add a subtitle containing a backlink to a page
1056          *
1057          * @param Title $title Title to link to
1058          * @param array $query Array of additional parameters to include in the link
1059          */
1060         public function addBacklinkSubtitle( Title $title, $query = [] ) {
1061                 $this->addSubtitle( self::buildBacklinkSubtitle( $title, $query ) );
1062         }
1063
1064         /**
1065          * Clear the subtitles
1066          */
1067         public function clearSubtitle() {
1068                 $this->mSubtitle = [];
1069         }
1070
1071         /**
1072          * Get the subtitle
1073          *
1074          * @return string
1075          */
1076         public function getSubtitle() {
1077                 return implode( "<br />\n\t\t\t\t", $this->mSubtitle );
1078         }
1079
1080         /**
1081          * Set the page as printable, i.e. it'll be displayed with all
1082          * print styles included
1083          */
1084         public function setPrintable() {
1085                 $this->mPrintable = true;
1086         }
1087
1088         /**
1089          * Return whether the page is "printable"
1090          *
1091          * @return bool
1092          */
1093         public function isPrintable() {
1094                 return $this->mPrintable;
1095         }
1096
1097         /**
1098          * Disable output completely, i.e. calling output() will have no effect
1099          */
1100         public function disable() {
1101                 $this->mDoNothing = true;
1102         }
1103
1104         /**
1105          * Return whether the output will be completely disabled
1106          *
1107          * @return bool
1108          */
1109         public function isDisabled() {
1110                 return $this->mDoNothing;
1111         }
1112
1113         /**
1114          * Show an "add new section" link?
1115          *
1116          * @return bool
1117          */
1118         public function showNewSectionLink() {
1119                 return $this->mNewSectionLink;
1120         }
1121
1122         /**
1123          * Forcibly hide the new section link?
1124          *
1125          * @return bool
1126          */
1127         public function forceHideNewSectionLink() {
1128                 return $this->mHideNewSectionLink;
1129         }
1130
1131         /**
1132          * Add or remove feed links in the page header
1133          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1134          * for the new version
1135          * @see addFeedLink()
1136          *
1137          * @param bool $show True: add default feeds, false: remove all feeds
1138          */
1139         public function setSyndicated( $show = true ) {
1140                 if ( $show ) {
1141                         $this->setFeedAppendQuery( false );
1142                 } else {
1143                         $this->mFeedLinks = [];
1144                 }
1145         }
1146
1147         /**
1148          * Add default feeds to the page header
1149          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1150          * for the new version
1151          * @see addFeedLink()
1152          *
1153          * @param string $val Query to append to feed links or false to output
1154          *        default links
1155          */
1156         public function setFeedAppendQuery( $val ) {
1157                 $this->mFeedLinks = [];
1158
1159                 foreach ( $this->getConfig()->get( 'AdvertisedFeedTypes' ) as $type ) {
1160                         $query = "feed=$type";
1161                         if ( is_string( $val ) ) {
1162                                 $query .= '&' . $val;
1163                         }
1164                         $this->mFeedLinks[$type] = $this->getTitle()->getLocalURL( $query );
1165                 }
1166         }
1167
1168         /**
1169          * Add a feed link to the page header
1170          *
1171          * @param string $format Feed type, should be a key of $wgFeedClasses
1172          * @param string $href URL
1173          */
1174         public function addFeedLink( $format, $href ) {
1175                 if ( in_array( $format, $this->getConfig()->get( 'AdvertisedFeedTypes' ) ) ) {
1176                         $this->mFeedLinks[$format] = $href;
1177                 }
1178         }
1179
1180         /**
1181          * Should we output feed links for this page?
1182          * @return bool
1183          */
1184         public function isSyndicated() {
1185                 return count( $this->mFeedLinks ) > 0;
1186         }
1187
1188         /**
1189          * Return URLs for each supported syndication format for this page.
1190          * @return array Associating format keys with URLs
1191          */
1192         public function getSyndicationLinks() {
1193                 return $this->mFeedLinks;
1194         }
1195
1196         /**
1197          * Will currently always return null
1198          *
1199          * @return null
1200          */
1201         public function getFeedAppendQuery() {
1202                 return $this->mFeedLinksAppendQuery;
1203         }
1204
1205         /**
1206          * Set whether the displayed content is related to the source of the
1207          * corresponding article on the wiki
1208          * Setting true will cause the change "article related" toggle to true
1209          *
1210          * @param bool $v
1211          */
1212         public function setArticleFlag( $v ) {
1213                 $this->mIsarticle = $v;
1214                 if ( $v ) {
1215                         $this->mIsArticleRelated = $v;
1216                 }
1217         }
1218
1219         /**
1220          * Return whether the content displayed page is related to the source of
1221          * the corresponding article on the wiki
1222          *
1223          * @return bool
1224          */
1225         public function isArticle() {
1226                 return $this->mIsarticle;
1227         }
1228
1229         /**
1230          * Set whether this page is related an article on the wiki
1231          * Setting false will cause the change of "article flag" toggle to false
1232          *
1233          * @param bool $v
1234          */
1235         public function setArticleRelated( $v ) {
1236                 $this->mIsArticleRelated = $v;
1237                 if ( !$v ) {
1238                         $this->mIsarticle = false;
1239                 }
1240         }
1241
1242         /**
1243          * Return whether this page is related an article on the wiki
1244          *
1245          * @return bool
1246          */
1247         public function isArticleRelated() {
1248                 return $this->mIsArticleRelated;
1249         }
1250
1251         /**
1252          * Add new language links
1253          *
1254          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1255          *                               (e.g. 'fr:Test page')
1256          */
1257         public function addLanguageLinks( array $newLinkArray ) {
1258                 $this->mLanguageLinks += $newLinkArray;
1259         }
1260
1261         /**
1262          * Reset the language links and add new language links
1263          *
1264          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1265          *                               (e.g. 'fr:Test page')
1266          */
1267         public function setLanguageLinks( array $newLinkArray ) {
1268                 $this->mLanguageLinks = $newLinkArray;
1269         }
1270
1271         /**
1272          * Get the list of language links
1273          *
1274          * @return string[] Array of interwiki-prefixed (non DB key) titles (e.g. 'fr:Test page')
1275          */
1276         public function getLanguageLinks() {
1277                 return $this->mLanguageLinks;
1278         }
1279
1280         /**
1281          * Add an array of categories, with names in the keys
1282          *
1283          * @param array $categories Mapping category name => sort key
1284          */
1285         public function addCategoryLinks( array $categories ) {
1286                 global $wgContLang;
1287
1288                 if ( !is_array( $categories ) || count( $categories ) == 0 ) {
1289                         return;
1290                 }
1291
1292                 $res = $this->addCategoryLinksToLBAndGetResult( $categories );
1293
1294                 # Set all the values to 'normal'.
1295                 $categories = array_fill_keys( array_keys( $categories ), 'normal' );
1296
1297                 # Mark hidden categories
1298                 foreach ( $res as $row ) {
1299                         if ( isset( $row->pp_value ) ) {
1300                                 $categories[$row->page_title] = 'hidden';
1301                         }
1302                 }
1303
1304                 // Avoid PHP 7.1 warning of passing $this by reference
1305                 $outputPage = $this;
1306                 # Add the remaining categories to the skin
1307                 if ( Hooks::run(
1308                         'OutputPageMakeCategoryLinks',
1309                         [ &$outputPage, $categories, &$this->mCategoryLinks ] )
1310                 ) {
1311                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1312                         foreach ( $categories as $category => $type ) {
1313                                 // array keys will cast numeric category names to ints, so cast back to string
1314                                 $category = (string)$category;
1315                                 $origcategory = $category;
1316                                 $title = Title::makeTitleSafe( NS_CATEGORY, $category );
1317                                 if ( !$title ) {
1318                                         continue;
1319                                 }
1320                                 $wgContLang->findVariantLink( $category, $title, true );
1321                                 if ( $category != $origcategory && array_key_exists( $category, $categories ) ) {
1322                                         continue;
1323                                 }
1324                                 $text = $wgContLang->convertHtml( $title->getText() );
1325                                 $this->mCategories[$type][] = $title->getText();
1326                                 $this->mCategoryLinks[$type][] = $linkRenderer->makeLink( $title, new HtmlArmor( $text ) );
1327                         }
1328                 }
1329         }
1330
1331         /**
1332          * @param array $categories
1333          * @return bool|ResultWrapper
1334          */
1335         protected function addCategoryLinksToLBAndGetResult( array $categories ) {
1336                 # Add the links to a LinkBatch
1337                 $arr = [ NS_CATEGORY => $categories ];
1338                 $lb = new LinkBatch;
1339                 $lb->setArray( $arr );
1340
1341                 # Fetch existence plus the hiddencat property
1342                 $dbr = wfGetDB( DB_REPLICA );
1343                 $fields = array_merge(
1344                         LinkCache::getSelectFields(),
1345                         [ 'page_namespace', 'page_title', 'pp_value' ]
1346                 );
1347
1348                 $res = $dbr->select( [ 'page', 'page_props' ],
1349                         $fields,
1350                         $lb->constructSet( 'page', $dbr ),
1351                         __METHOD__,
1352                         [],
1353                         [ 'page_props' => [ 'LEFT JOIN', [
1354                                 'pp_propname' => 'hiddencat',
1355                                 'pp_page = page_id'
1356                         ] ] ]
1357                 );
1358
1359                 # Add the results to the link cache
1360                 $lb->addResultToCache( LinkCache::singleton(), $res );
1361
1362                 return $res;
1363         }
1364
1365         /**
1366          * Reset the category links (but not the category list) and add $categories
1367          *
1368          * @param array $categories Mapping category name => sort key
1369          */
1370         public function setCategoryLinks( array $categories ) {
1371                 $this->mCategoryLinks = [];
1372                 $this->addCategoryLinks( $categories );
1373         }
1374
1375         /**
1376          * Get the list of category links, in a 2-D array with the following format:
1377          * $arr[$type][] = $link, where $type is either "normal" or "hidden" (for
1378          * hidden categories) and $link a HTML fragment with a link to the category
1379          * page
1380          *
1381          * @return array
1382          */
1383         public function getCategoryLinks() {
1384                 return $this->mCategoryLinks;
1385         }
1386
1387         /**
1388          * Get the list of category names this page belongs to.
1389          *
1390          * @param string $type The type of categories which should be returned. Possible values:
1391          *  * all: all categories of all types
1392          *  * hidden: only the hidden categories
1393          *  * normal: all categories, except hidden categories
1394          * @return array Array of strings
1395          */
1396         public function getCategories( $type = 'all' ) {
1397                 if ( $type === 'all' ) {
1398                         $allCategories = [];
1399                         foreach ( $this->mCategories as $categories ) {
1400                                 $allCategories = array_merge( $allCategories, $categories );
1401                         }
1402                         return $allCategories;
1403                 }
1404                 if ( !isset( $this->mCategories[$type] ) ) {
1405                         throw new InvalidArgumentException( 'Invalid category type given: ' . $type );
1406                 }
1407                 return $this->mCategories[$type];
1408         }
1409
1410         /**
1411          * Add an array of indicators, with their identifiers as array
1412          * keys and HTML contents as values.
1413          *
1414          * In case of duplicate keys, existing values are overwritten.
1415          *
1416          * @param array $indicators
1417          * @since 1.25
1418          */
1419         public function setIndicators( array $indicators ) {
1420                 $this->mIndicators = $indicators + $this->mIndicators;
1421                 // Keep ordered by key
1422                 ksort( $this->mIndicators );
1423         }
1424
1425         /**
1426          * Get the indicators associated with this page.
1427          *
1428          * The array will be internally ordered by item keys.
1429          *
1430          * @return array Keys: identifiers, values: HTML contents
1431          * @since 1.25
1432          */
1433         public function getIndicators() {
1434                 return $this->mIndicators;
1435         }
1436
1437         /**
1438          * Adds help link with an icon via page indicators.
1439          * Link target can be overridden by a local message containing a wikilink:
1440          * the message key is: lowercase action or special page name + '-helppage'.
1441          * @param string $to Target MediaWiki.org page title or encoded URL.
1442          * @param bool $overrideBaseUrl Whether $url is a full URL, to avoid MW.o.
1443          * @since 1.25
1444          */
1445         public function addHelpLink( $to, $overrideBaseUrl = false ) {
1446                 $this->addModuleStyles( 'mediawiki.helplink' );
1447                 $text = $this->msg( 'helppage-top-gethelp' )->escaped();
1448
1449                 if ( $overrideBaseUrl ) {
1450                         $helpUrl = $to;
1451                 } else {
1452                         $toUrlencoded = wfUrlencode( str_replace( ' ', '_', $to ) );
1453                         $helpUrl = "//www.mediawiki.org/wiki/Special:MyLanguage/$toUrlencoded";
1454                 }
1455
1456                 $link = Html::rawElement(
1457                         'a',
1458                         [
1459                                 'href' => $helpUrl,
1460                                 'target' => '_blank',
1461                                 'class' => 'mw-helplink',
1462                         ],
1463                         $text
1464                 );
1465
1466                 $this->setIndicators( [ 'mw-helplink' => $link ] );
1467         }
1468
1469         /**
1470          * Do not allow scripts which can be modified by wiki users to load on this page;
1471          * only allow scripts bundled with, or generated by, the software.
1472          * Site-wide styles are controlled by a config setting, since they can be
1473          * used to create a custom skin/theme, but not user-specific ones.
1474          *
1475          * @todo this should be given a more accurate name
1476          */
1477         public function disallowUserJs() {
1478                 $this->reduceAllowedModules(
1479                         ResourceLoaderModule::TYPE_SCRIPTS,
1480                         ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
1481                 );
1482
1483                 // Site-wide styles are controlled by a config setting, see T73621
1484                 // for background on why. User styles are never allowed.
1485                 if ( $this->getConfig()->get( 'AllowSiteCSSOnRestrictedPages' ) ) {
1486                         $styleOrigin = ResourceLoaderModule::ORIGIN_USER_SITEWIDE;
1487                 } else {
1488                         $styleOrigin = ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL;
1489                 }
1490                 $this->reduceAllowedModules(
1491                         ResourceLoaderModule::TYPE_STYLES,
1492                         $styleOrigin
1493                 );
1494         }
1495
1496         /**
1497          * Show what level of JavaScript / CSS untrustworthiness is allowed on this page
1498          * @see ResourceLoaderModule::$origin
1499          * @param string $type ResourceLoaderModule TYPE_ constant
1500          * @return int ResourceLoaderModule ORIGIN_ class constant
1501          */
1502         public function getAllowedModules( $type ) {
1503                 if ( $type == ResourceLoaderModule::TYPE_COMBINED ) {
1504                         return min( array_values( $this->mAllowedModules ) );
1505                 } else {
1506                         return isset( $this->mAllowedModules[$type] )
1507                                 ? $this->mAllowedModules[$type]
1508                                 : ResourceLoaderModule::ORIGIN_ALL;
1509                 }
1510         }
1511
1512         /**
1513          * Limit the highest level of CSS/JS untrustworthiness allowed.
1514          *
1515          * If passed the same or a higher level than the current level of untrustworthiness set, the
1516          * level will remain unchanged.
1517          *
1518          * @param string $type
1519          * @param int $level ResourceLoaderModule class constant
1520          */
1521         public function reduceAllowedModules( $type, $level ) {
1522                 $this->mAllowedModules[$type] = min( $this->getAllowedModules( $type ), $level );
1523         }
1524
1525         /**
1526          * Prepend $text to the body HTML
1527          *
1528          * @param string $text HTML
1529          */
1530         public function prependHTML( $text ) {
1531                 $this->mBodytext = $text . $this->mBodytext;
1532         }
1533
1534         /**
1535          * Append $text to the body HTML
1536          *
1537          * @param string $text HTML
1538          */
1539         public function addHTML( $text ) {
1540                 $this->mBodytext .= $text;
1541         }
1542
1543         /**
1544          * Shortcut for adding an Html::element via addHTML.
1545          *
1546          * @since 1.19
1547          *
1548          * @param string $element
1549          * @param array $attribs
1550          * @param string $contents
1551          */
1552         public function addElement( $element, array $attribs = [], $contents = '' ) {
1553                 $this->addHTML( Html::element( $element, $attribs, $contents ) );
1554         }
1555
1556         /**
1557          * Clear the body HTML
1558          */
1559         public function clearHTML() {
1560                 $this->mBodytext = '';
1561         }
1562
1563         /**
1564          * Get the body HTML
1565          *
1566          * @return string HTML
1567          */
1568         public function getHTML() {
1569                 return $this->mBodytext;
1570         }
1571
1572         /**
1573          * Get/set the ParserOptions object to use for wikitext parsing
1574          *
1575          * @param ParserOptions|null $options Either the ParserOption to use or null to only get the
1576          *   current ParserOption object. This parameter is deprecated since 1.31.
1577          * @return ParserOptions
1578          */
1579         public function parserOptions( $options = null ) {
1580                 if ( $options !== null ) {
1581                         wfDeprecated( __METHOD__ . ' with non-null $options', '1.31' );
1582                 }
1583
1584                 if ( $options !== null && !empty( $options->isBogus ) ) {
1585                         // Someone is trying to set a bogus pre-$wgUser PO. Check if it has
1586                         // been changed somehow, and keep it if so.
1587                         $anonPO = ParserOptions::newFromAnon();
1588                         $anonPO->setEditSection( false );
1589                         $anonPO->setAllowUnsafeRawHtml( false );
1590                         if ( !$options->matches( $anonPO ) ) {
1591                                 wfLogWarning( __METHOD__ . ': Setting a changed bogus ParserOptions: ' . wfGetAllCallers( 5 ) );
1592                                 $options->isBogus = false;
1593                         }
1594                 }
1595
1596                 if ( !$this->mParserOptions ) {
1597                         if ( !$this->getContext()->getUser()->isSafeToLoad() ) {
1598                                 // $wgUser isn't unstubbable yet, so don't try to get a
1599                                 // ParserOptions for it. And don't cache this ParserOptions
1600                                 // either.
1601                                 $po = ParserOptions::newFromAnon();
1602                                 $po->setEditSection( false );
1603                                 $po->setAllowUnsafeRawHtml( false );
1604                                 $po->isBogus = true;
1605                                 if ( $options !== null ) {
1606                                         $this->mParserOptions = empty( $options->isBogus ) ? $options : null;
1607                                 }
1608                                 return $po;
1609                         }
1610
1611                         $this->mParserOptions = ParserOptions::newFromContext( $this->getContext() );
1612                         $this->mParserOptions->setEditSection( false );
1613                         $this->mParserOptions->setAllowUnsafeRawHtml( false );
1614                 }
1615
1616                 if ( $options !== null && !empty( $options->isBogus ) ) {
1617                         // They're trying to restore the bogus pre-$wgUser PO. Do the right
1618                         // thing.
1619                         return wfSetVar( $this->mParserOptions, null, true );
1620                 } else {
1621                         return wfSetVar( $this->mParserOptions, $options );
1622                 }
1623         }
1624
1625         /**
1626          * Set the revision ID which will be seen by the wiki text parser
1627          * for things such as embedded {{REVISIONID}} variable use.
1628          *
1629          * @param int|null $revid An positive integer, or null
1630          * @return mixed Previous value
1631          */
1632         public function setRevisionId( $revid ) {
1633                 $val = is_null( $revid ) ? null : intval( $revid );
1634                 return wfSetVar( $this->mRevisionId, $val );
1635         }
1636
1637         /**
1638          * Get the displayed revision ID
1639          *
1640          * @return int
1641          */
1642         public function getRevisionId() {
1643                 return $this->mRevisionId;
1644         }
1645
1646         /**
1647          * Set the timestamp of the revision which will be displayed. This is used
1648          * to avoid a extra DB call in Skin::lastModified().
1649          *
1650          * @param string|null $timestamp
1651          * @return mixed Previous value
1652          */
1653         public function setRevisionTimestamp( $timestamp ) {
1654                 return wfSetVar( $this->mRevisionTimestamp, $timestamp );
1655         }
1656
1657         /**
1658          * Get the timestamp of displayed revision.
1659          * This will be null if not filled by setRevisionTimestamp().
1660          *
1661          * @return string|null
1662          */
1663         public function getRevisionTimestamp() {
1664                 return $this->mRevisionTimestamp;
1665         }
1666
1667         /**
1668          * Set the displayed file version
1669          *
1670          * @param File|bool $file
1671          * @return mixed Previous value
1672          */
1673         public function setFileVersion( $file ) {
1674                 $val = null;
1675                 if ( $file instanceof File && $file->exists() ) {
1676                         $val = [ 'time' => $file->getTimestamp(), 'sha1' => $file->getSha1() ];
1677                 }
1678                 return wfSetVar( $this->mFileVersion, $val, true );
1679         }
1680
1681         /**
1682          * Get the displayed file version
1683          *
1684          * @return array|null ('time' => MW timestamp, 'sha1' => sha1)
1685          */
1686         public function getFileVersion() {
1687                 return $this->mFileVersion;
1688         }
1689
1690         /**
1691          * Get the templates used on this page
1692          *
1693          * @return array (namespace => dbKey => revId)
1694          * @since 1.18
1695          */
1696         public function getTemplateIds() {
1697                 return $this->mTemplateIds;
1698         }
1699
1700         /**
1701          * Get the files used on this page
1702          *
1703          * @return array (dbKey => array('time' => MW timestamp or null, 'sha1' => sha1 or ''))
1704          * @since 1.18
1705          */
1706         public function getFileSearchOptions() {
1707                 return $this->mImageTimeKeys;
1708         }
1709
1710         /**
1711          * Convert wikitext to HTML and add it to the buffer
1712          * Default assumes that the current page title will be used.
1713          *
1714          * @param string $text
1715          * @param bool $linestart Is this the start of a line?
1716          * @param bool $interface Is this text in the user interface language?
1717          * @throws MWException
1718          */
1719         public function addWikiText( $text, $linestart = true, $interface = true ) {
1720                 $title = $this->getTitle(); // Work around E_STRICT
1721                 if ( !$title ) {
1722                         throw new MWException( 'Title is null' );
1723                 }
1724                 $this->addWikiTextTitle( $text, $title, $linestart, /*tidy*/false, $interface );
1725         }
1726
1727         /**
1728          * Add wikitext with a custom Title object
1729          *
1730          * @param string $text Wikitext
1731          * @param Title &$title
1732          * @param bool $linestart Is this the start of a line?
1733          */
1734         public function addWikiTextWithTitle( $text, &$title, $linestart = true ) {
1735                 $this->addWikiTextTitle( $text, $title, $linestart );
1736         }
1737
1738         /**
1739          * Add wikitext with a custom Title object and tidy enabled.
1740          *
1741          * @param string $text Wikitext
1742          * @param Title &$title
1743          * @param bool $linestart Is this the start of a line?
1744          */
1745         function addWikiTextTitleTidy( $text, &$title, $linestart = true ) {
1746                 $this->addWikiTextTitle( $text, $title, $linestart, true );
1747         }
1748
1749         /**
1750          * Add wikitext with tidy enabled
1751          *
1752          * @param string $text Wikitext
1753          * @param bool $linestart Is this the start of a line?
1754          */
1755         public function addWikiTextTidy( $text, $linestart = true ) {
1756                 $title = $this->getTitle();
1757                 $this->addWikiTextTitleTidy( $text, $title, $linestart );
1758         }
1759
1760         /**
1761          * Add wikitext with a custom Title object
1762          *
1763          * @param string $text Wikitext
1764          * @param Title $title
1765          * @param bool $linestart Is this the start of a line?
1766          * @param bool $tidy Whether to use tidy
1767          * @param bool $interface Whether it is an interface message
1768          *   (for example disables conversion)
1769          */
1770         public function addWikiTextTitle( $text, Title $title, $linestart,
1771                 $tidy = false, $interface = false
1772         ) {
1773                 global $wgParser;
1774
1775                 $popts = $this->parserOptions();
1776                 $oldTidy = $popts->setTidy( $tidy );
1777                 $popts->setInterfaceMessage( (bool)$interface );
1778
1779                 $parserOutput = $wgParser->getFreshParser()->parse(
1780                         $text, $title, $popts,
1781                         $linestart, true, $this->mRevisionId
1782                 );
1783
1784                 $popts->setTidy( $oldTidy );
1785
1786                 $this->addParserOutput( $parserOutput, [
1787                         'enableSectionEditLinks' => false,
1788                 ] );
1789         }
1790
1791         /**
1792          * Add all metadata associated with a ParserOutput object, but without the actual HTML. This
1793          * includes categories, language links, ResourceLoader modules, effects of certain magic words,
1794          * and so on.
1795          *
1796          * @since 1.24
1797          * @param ParserOutput $parserOutput
1798          */
1799         public function addParserOutputMetadata( $parserOutput ) {
1800                 $this->mLanguageLinks += $parserOutput->getLanguageLinks();
1801                 $this->addCategoryLinks( $parserOutput->getCategories() );
1802                 $this->setIndicators( $parserOutput->getIndicators() );
1803                 $this->mNewSectionLink = $parserOutput->getNewSection();
1804                 $this->mHideNewSectionLink = $parserOutput->getHideNewSection();
1805
1806                 if ( !$parserOutput->isCacheable() ) {
1807                         $this->enableClientCache( false );
1808                 }
1809                 $this->mNoGallery = $parserOutput->getNoGallery();
1810                 $this->mHeadItems = array_merge( $this->mHeadItems, $parserOutput->getHeadItems() );
1811                 $this->addModules( $parserOutput->getModules() );
1812                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1813                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1814                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1815                 $this->mPreventClickjacking = $this->mPreventClickjacking
1816                         || $parserOutput->preventClickjacking();
1817
1818                 // Template versioning...
1819                 foreach ( (array)$parserOutput->getTemplateIds() as $ns => $dbks ) {
1820                         if ( isset( $this->mTemplateIds[$ns] ) ) {
1821                                 $this->mTemplateIds[$ns] = $dbks + $this->mTemplateIds[$ns];
1822                         } else {
1823                                 $this->mTemplateIds[$ns] = $dbks;
1824                         }
1825                 }
1826                 // File versioning...
1827                 foreach ( (array)$parserOutput->getFileSearchOptions() as $dbk => $data ) {
1828                         $this->mImageTimeKeys[$dbk] = $data;
1829                 }
1830
1831                 // Hooks registered in the object
1832                 $parserOutputHooks = $this->getConfig()->get( 'ParserOutputHooks' );
1833                 foreach ( $parserOutput->getOutputHooks() as $hookInfo ) {
1834                         list( $hookName, $data ) = $hookInfo;
1835                         if ( isset( $parserOutputHooks[$hookName] ) ) {
1836                                 call_user_func( $parserOutputHooks[$hookName], $this, $parserOutput, $data );
1837                         }
1838                 }
1839
1840                 // Enable OOUI if requested via ParserOutput
1841                 if ( $parserOutput->getEnableOOUI() ) {
1842                         $this->enableOOUI();
1843                 }
1844
1845                 // Include parser limit report
1846                 if ( !$this->limitReportJSData ) {
1847                         $this->limitReportJSData = $parserOutput->getLimitReportJSData();
1848                 }
1849
1850                 // Link flags are ignored for now, but may in the future be
1851                 // used to mark individual language links.
1852                 $linkFlags = [];
1853                 // Avoid PHP 7.1 warning of passing $this by reference
1854                 $outputPage = $this;
1855                 Hooks::run( 'LanguageLinks', [ $this->getTitle(), &$this->mLanguageLinks, &$linkFlags ] );
1856                 Hooks::runWithoutAbort( 'OutputPageParserOutput', [ &$outputPage, $parserOutput ] );
1857
1858                 // This check must be after 'OutputPageParserOutput' runs in addParserOutputMetadata
1859                 // so that extensions may modify ParserOutput to toggle TOC.
1860                 // This cannot be moved to addParserOutputText because that is not
1861                 // called by EditPage for Preview.
1862                 if ( $parserOutput->getTOCEnabled() && $parserOutput->getTOCHTML() ) {
1863                         $this->mEnableTOC = true;
1864                 }
1865         }
1866
1867         /**
1868          * Add the HTML and enhancements for it (like ResourceLoader modules) associated with a
1869          * ParserOutput object, without any other metadata.
1870          *
1871          * @since 1.24
1872          * @param ParserOutput $parserOutput
1873          * @param array $poOptions Options to ParserOutput::getText()
1874          */
1875         public function addParserOutputContent( $parserOutput, $poOptions = [] ) {
1876                 $this->addParserOutputText( $parserOutput, $poOptions );
1877
1878                 $this->addModules( $parserOutput->getModules() );
1879                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1880                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1881
1882                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1883         }
1884
1885         /**
1886          * Add the HTML associated with a ParserOutput object, without any metadata.
1887          *
1888          * @since 1.24
1889          * @param ParserOutput $parserOutput
1890          * @param array $poOptions Options to ParserOutput::getText()
1891          */
1892         public function addParserOutputText( $parserOutput, $poOptions = [] ) {
1893                 $text = $parserOutput->getText( $poOptions );
1894                 // Avoid PHP 7.1 warning of passing $this by reference
1895                 $outputPage = $this;
1896                 Hooks::runWithoutAbort( 'OutputPageBeforeHTML', [ &$outputPage, &$text ] );
1897                 $this->addHTML( $text );
1898         }
1899
1900         /**
1901          * Add everything from a ParserOutput object.
1902          *
1903          * @param ParserOutput $parserOutput
1904          * @param array $poOptions Options to ParserOutput::getText()
1905          */
1906         function addParserOutput( $parserOutput, $poOptions = [] ) {
1907                 $this->addParserOutputMetadata( $parserOutput );
1908
1909                 // Touch section edit links only if not previously disabled
1910                 if ( $parserOutput->getEditSectionTokens() ) {
1911                         $parserOutput->setEditSectionTokens( $this->mEnableSectionEditLinks );
1912                 }
1913                 if ( !$this->mEnableSectionEditLinks
1914                         && !array_key_exists( 'enableSectionEditLinks', $poOptions )
1915                 ) {
1916                         $poOptions['enableSectionEditLinks'] = false;
1917                 }
1918
1919                 $this->addParserOutputText( $parserOutput, $poOptions );
1920         }
1921
1922         /**
1923          * Add the output of a QuickTemplate to the output buffer
1924          *
1925          * @param QuickTemplate &$template
1926          */
1927         public function addTemplate( &$template ) {
1928                 $this->addHTML( $template->getHTML() );
1929         }
1930
1931         /**
1932          * Parse wikitext and return the HTML.
1933          *
1934          * @param string $text
1935          * @param bool $linestart Is this the start of a line?
1936          * @param bool $interface Use interface language ($wgLang instead of
1937          *   $wgContLang) while parsing language sensitive magic words like GRAMMAR and PLURAL.
1938          *   This also disables LanguageConverter.
1939          * @param Language $language Target language object, will override $interface
1940          * @throws MWException
1941          * @return string HTML
1942          */
1943         public function parse( $text, $linestart = true, $interface = false, $language = null ) {
1944                 global $wgParser;
1945
1946                 if ( is_null( $this->getTitle() ) ) {
1947                         throw new MWException( 'Empty $mTitle in ' . __METHOD__ );
1948                 }
1949
1950                 $popts = $this->parserOptions();
1951                 if ( $interface ) {
1952                         $popts->setInterfaceMessage( true );
1953                 }
1954                 if ( $language !== null ) {
1955                         $oldLang = $popts->setTargetLanguage( $language );
1956                 }
1957
1958                 $parserOutput = $wgParser->getFreshParser()->parse(
1959                         $text, $this->getTitle(), $popts,
1960                         $linestart, true, $this->mRevisionId
1961                 );
1962
1963                 if ( $interface ) {
1964                         $popts->setInterfaceMessage( false );
1965                 }
1966                 if ( $language !== null ) {
1967                         $popts->setTargetLanguage( $oldLang );
1968                 }
1969
1970                 return $parserOutput->getText( [
1971                         'enableSectionEditLinks' => false,
1972                 ] );
1973         }
1974
1975         /**
1976          * Parse wikitext, strip paragraphs, and return the HTML.
1977          *
1978          * @param string $text
1979          * @param bool $linestart Is this the start of a line?
1980          * @param bool $interface Use interface language ($wgLang instead of
1981          *   $wgContLang) while parsing language sensitive magic
1982          *   words like GRAMMAR and PLURAL
1983          * @return string HTML
1984          */
1985         public function parseInline( $text, $linestart = true, $interface = false ) {
1986                 $parsed = $this->parse( $text, $linestart, $interface );
1987                 return Parser::stripOuterParagraph( $parsed );
1988         }
1989
1990         /**
1991          * @param int $maxage
1992          * @deprecated since 1.27 Use setCdnMaxage() instead
1993          */
1994         public function setSquidMaxage( $maxage ) {
1995                 wfDeprecated( __METHOD__, '1.27' );
1996                 $this->setCdnMaxage( $maxage );
1997         }
1998
1999         /**
2000          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header
2001          *
2002          * @param int $maxage Maximum cache time on the CDN, in seconds.
2003          */
2004         public function setCdnMaxage( $maxage ) {
2005                 $this->mCdnMaxage = min( $maxage, $this->mCdnMaxageLimit );
2006         }
2007
2008         /**
2009          * Lower the value of the "s-maxage" part of the "Cache-control" HTTP header
2010          *
2011          * @param int $maxage Maximum cache time on the CDN, in seconds
2012          * @since 1.27
2013          */
2014         public function lowerCdnMaxage( $maxage ) {
2015                 $this->mCdnMaxageLimit = min( $maxage, $this->mCdnMaxageLimit );
2016                 $this->setCdnMaxage( $this->mCdnMaxage );
2017         }
2018
2019         /**
2020          * Get TTL in [$minTTL,$maxTTL] in pass it to lowerCdnMaxage()
2021          *
2022          * This sets and returns $minTTL if $mtime is false or null. Otherwise,
2023          * the TTL is higher the older the $mtime timestamp is. Essentially, the
2024          * TTL is 90% of the age of the object, subject to the min and max.
2025          *
2026          * @param string|int|float|bool|null $mtime Last-Modified timestamp
2027          * @param int $minTTL Mimimum TTL in seconds [default: 1 minute]
2028          * @param int $maxTTL Maximum TTL in seconds [default: $wgSquidMaxage]
2029          * @return int TTL in seconds
2030          * @since 1.28
2031          */
2032         public function adaptCdnTTL( $mtime, $minTTL = 0, $maxTTL = 0 ) {
2033                 $minTTL = $minTTL ?: IExpiringStore::TTL_MINUTE;
2034                 $maxTTL = $maxTTL ?: $this->getConfig()->get( 'SquidMaxage' );
2035
2036                 if ( $mtime === null || $mtime === false ) {
2037                         return $minTTL; // entity does not exist
2038                 }
2039
2040                 $age = time() - wfTimestamp( TS_UNIX, $mtime );
2041                 $adaptiveTTL = max( 0.9 * $age, $minTTL );
2042                 $adaptiveTTL = min( $adaptiveTTL, $maxTTL );
2043
2044                 $this->lowerCdnMaxage( (int)$adaptiveTTL );
2045
2046                 return $adaptiveTTL;
2047         }
2048
2049         /**
2050          * Use enableClientCache(false) to force it to send nocache headers
2051          *
2052          * @param bool $state
2053          *
2054          * @return bool
2055          */
2056         public function enableClientCache( $state ) {
2057                 return wfSetVar( $this->mEnableClientCache, $state );
2058         }
2059
2060         /**
2061          * Get the list of cookies that will influence on the cache
2062          *
2063          * @return array
2064          */
2065         function getCacheVaryCookies() {
2066                 static $cookies;
2067                 if ( $cookies === null ) {
2068                         $config = $this->getConfig();
2069                         $cookies = array_merge(
2070                                 SessionManager::singleton()->getVaryCookies(),
2071                                 [
2072                                         'forceHTTPS',
2073                                 ],
2074                                 $config->get( 'CacheVaryCookies' )
2075                         );
2076                         Hooks::run( 'GetCacheVaryCookies', [ $this, &$cookies ] );
2077                 }
2078                 return $cookies;
2079         }
2080
2081         /**
2082          * Check if the request has a cache-varying cookie header
2083          * If it does, it's very important that we don't allow public caching
2084          *
2085          * @return bool
2086          */
2087         function haveCacheVaryCookies() {
2088                 $request = $this->getRequest();
2089                 foreach ( $this->getCacheVaryCookies() as $cookieName ) {
2090                         if ( $request->getCookie( $cookieName, '', '' ) !== '' ) {
2091                                 wfDebug( __METHOD__ . ": found $cookieName\n" );
2092                                 return true;
2093                         }
2094                 }
2095                 wfDebug( __METHOD__ . ": no cache-varying cookies found\n" );
2096                 return false;
2097         }
2098
2099         /**
2100          * Add an HTTP header that will influence on the cache
2101          *
2102          * @param string $header Header name
2103          * @param string[]|null $option Options for the Key header. See
2104          * https://datatracker.ietf.org/doc/draft-fielding-http-key/
2105          * for the list of valid options.
2106          */
2107         public function addVaryHeader( $header, array $option = null ) {
2108                 if ( !array_key_exists( $header, $this->mVaryHeader ) ) {
2109                         $this->mVaryHeader[$header] = [];
2110                 }
2111                 if ( !is_array( $option ) ) {
2112                         $option = [];
2113                 }
2114                 $this->mVaryHeader[$header] = array_unique( array_merge( $this->mVaryHeader[$header], $option ) );
2115         }
2116
2117         /**
2118          * Return a Vary: header on which to vary caches. Based on the keys of $mVaryHeader,
2119          * such as Accept-Encoding or Cookie
2120          *
2121          * @return string
2122          */
2123         public function getVaryHeader() {
2124                 // If we vary on cookies, let's make sure it's always included here too.
2125                 if ( $this->getCacheVaryCookies() ) {
2126                         $this->addVaryHeader( 'Cookie' );
2127                 }
2128
2129                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2130                         $this->addVaryHeader( $header, $options );
2131                 }
2132                 return 'Vary: ' . implode( ', ', array_keys( $this->mVaryHeader ) );
2133         }
2134
2135         /**
2136          * Add an HTTP Link: header
2137          *
2138          * @param string $header Header value
2139          */
2140         public function addLinkHeader( $header ) {
2141                 $this->mLinkHeader[] = $header;
2142         }
2143
2144         /**
2145          * Return a Link: header. Based on the values of $mLinkHeader.
2146          *
2147          * @return string
2148          */
2149         public function getLinkHeader() {
2150                 if ( !$this->mLinkHeader ) {
2151                         return false;
2152                 }
2153
2154                 return 'Link: ' . implode( ',', $this->mLinkHeader );
2155         }
2156
2157         /**
2158          * Get a complete Key header
2159          *
2160          * @return string
2161          */
2162         public function getKeyHeader() {
2163                 $cvCookies = $this->getCacheVaryCookies();
2164
2165                 $cookiesOption = [];
2166                 foreach ( $cvCookies as $cookieName ) {
2167                         $cookiesOption[] = 'param=' . $cookieName;
2168                 }
2169                 $this->addVaryHeader( 'Cookie', $cookiesOption );
2170
2171                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2172                         $this->addVaryHeader( $header, $options );
2173                 }
2174
2175                 $headers = [];
2176                 foreach ( $this->mVaryHeader as $header => $option ) {
2177                         $newheader = $header;
2178                         if ( is_array( $option ) && count( $option ) > 0 ) {
2179                                 $newheader .= ';' . implode( ';', $option );
2180                         }
2181                         $headers[] = $newheader;
2182                 }
2183                 $key = 'Key: ' . implode( ',', $headers );
2184
2185                 return $key;
2186         }
2187
2188         /**
2189          * T23672: Add Accept-Language to Vary and Key headers
2190          * if there's no 'variant' parameter existed in GET.
2191          *
2192          * For example:
2193          *   /w/index.php?title=Main_page should always be served; but
2194          *   /w/index.php?title=Main_page&variant=zh-cn should never be served.
2195          */
2196         function addAcceptLanguage() {
2197                 $title = $this->getTitle();
2198                 if ( !$title instanceof Title ) {
2199                         return;
2200                 }
2201
2202                 $lang = $title->getPageLanguage();
2203                 if ( !$this->getRequest()->getCheck( 'variant' ) && $lang->hasVariants() ) {
2204                         $variants = $lang->getVariants();
2205                         $aloption = [];
2206                         foreach ( $variants as $variant ) {
2207                                 if ( $variant === $lang->getCode() ) {
2208                                         continue;
2209                                 } else {
2210                                         $aloption[] = 'substr=' . $variant;
2211
2212                                         // IE and some other browsers use BCP 47 standards in
2213                                         // their Accept-Language header, like "zh-CN" or "zh-Hant".
2214                                         // We should handle these too.
2215                                         $variantBCP47 = LanguageCode::bcp47( $variant );
2216                                         if ( $variantBCP47 !== $variant ) {
2217                                                 $aloption[] = 'substr=' . $variantBCP47;
2218                                         }
2219                                 }
2220                         }
2221                         $this->addVaryHeader( 'Accept-Language', $aloption );
2222                 }
2223         }
2224
2225         /**
2226          * Set a flag which will cause an X-Frame-Options header appropriate for
2227          * edit pages to be sent. The header value is controlled by
2228          * $wgEditPageFrameOptions.
2229          *
2230          * This is the default for special pages. If you display a CSRF-protected
2231          * form on an ordinary view page, then you need to call this function.
2232          *
2233          * @param bool $enable
2234          */
2235         public function preventClickjacking( $enable = true ) {
2236                 $this->mPreventClickjacking = $enable;
2237         }
2238
2239         /**
2240          * Turn off frame-breaking. Alias for $this->preventClickjacking(false).
2241          * This can be called from pages which do not contain any CSRF-protected
2242          * HTML form.
2243          */
2244         public function allowClickjacking() {
2245                 $this->mPreventClickjacking = false;
2246         }
2247
2248         /**
2249          * Get the prevent-clickjacking flag
2250          *
2251          * @since 1.24
2252          * @return bool
2253          */
2254         public function getPreventClickjacking() {
2255                 return $this->mPreventClickjacking;
2256         }
2257
2258         /**
2259          * Get the X-Frame-Options header value (without the name part), or false
2260          * if there isn't one. This is used by Skin to determine whether to enable
2261          * JavaScript frame-breaking, for clients that don't support X-Frame-Options.
2262          *
2263          * @return string|false
2264          */
2265         public function getFrameOptions() {
2266                 $config = $this->getConfig();
2267                 if ( $config->get( 'BreakFrames' ) ) {
2268                         return 'DENY';
2269                 } elseif ( $this->mPreventClickjacking && $config->get( 'EditPageFrameOptions' ) ) {
2270                         return $config->get( 'EditPageFrameOptions' );
2271                 }
2272                 return false;
2273         }
2274
2275         /**
2276          * Send cache control HTTP headers
2277          */
2278         public function sendCacheControl() {
2279                 $response = $this->getRequest()->response();
2280                 $config = $this->getConfig();
2281
2282                 $this->addVaryHeader( 'Cookie' );
2283                 $this->addAcceptLanguage();
2284
2285                 # don't serve compressed data to clients who can't handle it
2286                 # maintain different caches for logged-in users and non-logged in ones
2287                 $response->header( $this->getVaryHeader() );
2288
2289                 if ( $config->get( 'UseKeyHeader' ) ) {
2290                         $response->header( $this->getKeyHeader() );
2291                 }
2292
2293                 if ( $this->mEnableClientCache ) {
2294                         if (
2295                                 $config->get( 'UseSquid' ) &&
2296                                 !$response->hasCookies() &&
2297                                 !SessionManager::getGlobalSession()->isPersistent() &&
2298                                 !$this->isPrintable() &&
2299                                 $this->mCdnMaxage != 0 &&
2300                                 !$this->haveCacheVaryCookies()
2301                         ) {
2302                                 if ( $config->get( 'UseESI' ) ) {
2303                                         # We'll purge the proxy cache explicitly, but require end user agents
2304                                         # to revalidate against the proxy on each visit.
2305                                         # Surrogate-Control controls our CDN, Cache-Control downstream caches
2306                                         wfDebug( __METHOD__ .
2307                                                 ": proxy caching with ESI; {$this->mLastModified} **", 'private' );
2308                                         # start with a shorter timeout for initial testing
2309                                         # header( 'Surrogate-Control: max-age=2678400+2678400, content="ESI/1.0"');
2310                                         $response->header(
2311                                                 "Surrogate-Control: max-age={$config->get( 'SquidMaxage' )}" .
2312                                                 "+{$this->mCdnMaxage}, content=\"ESI/1.0\""
2313                                         );
2314                                         $response->header( 'Cache-Control: s-maxage=0, must-revalidate, max-age=0' );
2315                                 } else {
2316                                         # We'll purge the proxy cache for anons explicitly, but require end user agents
2317                                         # to revalidate against the proxy on each visit.
2318                                         # IMPORTANT! The CDN needs to replace the Cache-Control header with
2319                                         # Cache-Control: s-maxage=0, must-revalidate, max-age=0
2320                                         wfDebug( __METHOD__ .
2321                                                 ": local proxy caching; {$this->mLastModified} **", 'private' );
2322                                         # start with a shorter timeout for initial testing
2323                                         # header( "Cache-Control: s-maxage=2678400, must-revalidate, max-age=0" );
2324                                         $response->header( "Cache-Control: " .
2325                                                 "s-maxage={$this->mCdnMaxage}, must-revalidate, max-age=0" );
2326                                 }
2327                         } else {
2328                                 # We do want clients to cache if they can, but they *must* check for updates
2329                                 # on revisiting the page.
2330                                 wfDebug( __METHOD__ . ": private caching; {$this->mLastModified} **", 'private' );
2331                                 $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2332                                 $response->header( "Cache-Control: private, must-revalidate, max-age=0" );
2333                         }
2334                         if ( $this->mLastModified ) {
2335                                 $response->header( "Last-Modified: {$this->mLastModified}" );
2336                         }
2337                 } else {
2338                         wfDebug( __METHOD__ . ": no caching **", 'private' );
2339
2340                         # In general, the absence of a last modified header should be enough to prevent
2341                         # the client from using its cache. We send a few other things just to make sure.
2342                         $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2343                         $response->header( 'Cache-Control: no-cache, no-store, max-age=0, must-revalidate' );
2344                         $response->header( 'Pragma: no-cache' );
2345                 }
2346         }
2347
2348         /**
2349          * Finally, all the text has been munged and accumulated into
2350          * the object, let's actually output it:
2351          *
2352          * @param bool $return Set to true to get the result as a string rather than sending it
2353          * @return string|null
2354          * @throws Exception
2355          * @throws FatalError
2356          * @throws MWException
2357          */
2358         public function output( $return = false ) {
2359                 global $wgContLang;
2360
2361                 if ( $this->mDoNothing ) {
2362                         return $return ? '' : null;
2363                 }
2364
2365                 $response = $this->getRequest()->response();
2366                 $config = $this->getConfig();
2367
2368                 if ( $this->mRedirect != '' ) {
2369                         # Standards require redirect URLs to be absolute
2370                         $this->mRedirect = wfExpandUrl( $this->mRedirect, PROTO_CURRENT );
2371
2372                         $redirect = $this->mRedirect;
2373                         $code = $this->mRedirectCode;
2374
2375                         if ( Hooks::run( "BeforePageRedirect", [ $this, &$redirect, &$code ] ) ) {
2376                                 if ( $code == '301' || $code == '303' ) {
2377                                         if ( !$config->get( 'DebugRedirects' ) ) {
2378                                                 $response->statusHeader( $code );
2379                                         }
2380                                         $this->mLastModified = wfTimestamp( TS_RFC2822 );
2381                                 }
2382                                 if ( $config->get( 'VaryOnXFP' ) ) {
2383                                         $this->addVaryHeader( 'X-Forwarded-Proto' );
2384                                 }
2385                                 $this->sendCacheControl();
2386
2387                                 $response->header( "Content-Type: text/html; charset=utf-8" );
2388                                 if ( $config->get( 'DebugRedirects' ) ) {
2389                                         $url = htmlspecialchars( $redirect );
2390                                         print "<!DOCTYPE html>\n<html>\n<head>\n<title>Redirect</title>\n</head>\n<body>\n";
2391                                         print "<p>Location: <a href=\"$url\">$url</a></p>\n";
2392                                         print "</body>\n</html>\n";
2393                                 } else {
2394                                         $response->header( 'Location: ' . $redirect );
2395                                 }
2396                         }
2397
2398                         return $return ? '' : null;
2399                 } elseif ( $this->mStatusCode ) {
2400                         $response->statusHeader( $this->mStatusCode );
2401                 }
2402
2403                 # Buffer output; final headers may depend on later processing
2404                 ob_start();
2405
2406                 $response->header( 'Content-type: ' . $config->get( 'MimeType' ) . '; charset=UTF-8' );
2407                 $response->header( 'Content-language: ' . $wgContLang->getHtmlCode() );
2408
2409                 // Avoid Internet Explorer "compatibility view" in IE 8-10, so that
2410                 // jQuery etc. can work correctly.
2411                 $response->header( 'X-UA-Compatible: IE=Edge' );
2412
2413                 if ( !$this->mArticleBodyOnly ) {
2414                         $sk = $this->getSkin();
2415
2416                         if ( $sk->shouldPreloadLogo() ) {
2417                                 $this->addLogoPreloadLinkHeaders();
2418                         }
2419                 }
2420
2421                 $linkHeader = $this->getLinkHeader();
2422                 if ( $linkHeader ) {
2423                         $response->header( $linkHeader );
2424                 }
2425
2426                 // Prevent framing, if requested
2427                 $frameOptions = $this->getFrameOptions();
2428                 if ( $frameOptions ) {
2429                         $response->header( "X-Frame-Options: $frameOptions" );
2430                 }
2431
2432                 if ( $this->mArticleBodyOnly ) {
2433                         echo $this->mBodytext;
2434                 } else {
2435                         // Enable safe mode if requested
2436                         if ( $this->getRequest()->getBool( 'safemode' ) ) {
2437                                 $this->disallowUserJs();
2438                         }
2439
2440                         $sk = $this->getSkin();
2441                         foreach ( $sk->getDefaultModules() as $group ) {
2442                                 $this->addModules( $group );
2443                         }
2444
2445                         MWDebug::addModules( $this );
2446
2447                         // Avoid PHP 7.1 warning of passing $this by reference
2448                         $outputPage = $this;
2449                         // Hook that allows last minute changes to the output page, e.g.
2450                         // adding of CSS or Javascript by extensions.
2451                         Hooks::runWithoutAbort( 'BeforePageDisplay', [ &$outputPage, &$sk ] );
2452
2453                         try {
2454                                 $sk->outputPage();
2455                         } catch ( Exception $e ) {
2456                                 ob_end_clean(); // bug T129657
2457                                 throw $e;
2458                         }
2459                 }
2460
2461                 try {
2462                         // This hook allows last minute changes to final overall output by modifying output buffer
2463                         Hooks::runWithoutAbort( 'AfterFinalPageOutput', [ $this ] );
2464                 } catch ( Exception $e ) {
2465                         ob_end_clean(); // bug T129657
2466                         throw $e;
2467                 }
2468
2469                 $this->sendCacheControl();
2470
2471                 if ( $return ) {
2472                         return ob_get_clean();
2473                 } else {
2474                         ob_end_flush();
2475                         return null;
2476                 }
2477         }
2478
2479         /**
2480          * Prepare this object to display an error page; disable caching and
2481          * indexing, clear the current text and redirect, set the page's title
2482          * and optionally an custom HTML title (content of the "<title>" tag).
2483          *
2484          * @param string|Message $pageTitle Will be passed directly to setPageTitle()
2485          * @param string|Message $htmlTitle Will be passed directly to setHTMLTitle();
2486          *                   optional, if not passed the "<title>" attribute will be
2487          *                   based on $pageTitle
2488          */
2489         public function prepareErrorPage( $pageTitle, $htmlTitle = false ) {
2490                 $this->setPageTitle( $pageTitle );
2491                 if ( $htmlTitle !== false ) {
2492                         $this->setHTMLTitle( $htmlTitle );
2493                 }
2494                 $this->setRobotPolicy( 'noindex,nofollow' );
2495                 $this->setArticleRelated( false );
2496                 $this->enableClientCache( false );
2497                 $this->mRedirect = '';
2498                 $this->clearSubtitle();
2499                 $this->clearHTML();
2500         }
2501
2502         /**
2503          * Output a standard error page
2504          *
2505          * showErrorPage( 'titlemsg', 'pagetextmsg' );
2506          * showErrorPage( 'titlemsg', 'pagetextmsg', [ 'param1', 'param2' ] );
2507          * showErrorPage( 'titlemsg', $messageObject );
2508          * showErrorPage( $titleMessageObject, $messageObject );
2509          *
2510          * @param string|Message $title Message key (string) for page title, or a Message object
2511          * @param string|Message $msg Message key (string) for page text, or a Message object
2512          * @param array $params Message parameters; ignored if $msg is a Message object
2513          */
2514         public function showErrorPage( $title, $msg, $params = [] ) {
2515                 if ( !$title instanceof Message ) {
2516                         $title = $this->msg( $title );
2517                 }
2518
2519                 $this->prepareErrorPage( $title );
2520
2521                 if ( $msg instanceof Message ) {
2522                         if ( $params !== [] ) {
2523                                 trigger_error( 'Argument ignored: $params. The message parameters argument '
2524                                         . 'is discarded when the $msg argument is a Message object instead of '
2525                                         . 'a string.', E_USER_NOTICE );
2526                         }
2527                         $this->addHTML( $msg->parseAsBlock() );
2528                 } else {
2529                         $this->addWikiMsgArray( $msg, $params );
2530                 }
2531
2532                 $this->returnToMain();
2533         }
2534
2535         /**
2536          * Output a standard permission error page
2537          *
2538          * @param array $errors Error message keys or [key, param...] arrays
2539          * @param string $action Action that was denied or null if unknown
2540          */
2541         public function showPermissionsErrorPage( array $errors, $action = null ) {
2542                 foreach ( $errors as $key => $error ) {
2543                         $errors[$key] = (array)$error;
2544                 }
2545
2546                 // For some action (read, edit, create and upload), display a "login to do this action"
2547                 // error if all of the following conditions are met:
2548                 // 1. the user is not logged in
2549                 // 2. the only error is insufficient permissions (i.e. no block or something else)
2550                 // 3. the error can be avoided simply by logging in
2551                 if ( in_array( $action, [ 'read', 'edit', 'createpage', 'createtalk', 'upload' ] )
2552                         && $this->getUser()->isAnon() && count( $errors ) == 1 && isset( $errors[0][0] )
2553                         && ( $errors[0][0] == 'badaccess-groups' || $errors[0][0] == 'badaccess-group0' )
2554                         && ( User::groupHasPermission( 'user', $action )
2555                         || User::groupHasPermission( 'autoconfirmed', $action ) )
2556                 ) {
2557                         $displayReturnto = null;
2558
2559                         # Due to T34276, if a user does not have read permissions,
2560                         # $this->getTitle() will just give Special:Badtitle, which is
2561                         # not especially useful as a returnto parameter. Use the title
2562                         # from the request instead, if there was one.
2563                         $request = $this->getRequest();
2564                         $returnto = Title::newFromText( $request->getVal( 'title', '' ) );
2565                         if ( $action == 'edit' ) {
2566                                 $msg = 'whitelistedittext';
2567                                 $displayReturnto = $returnto;
2568                         } elseif ( $action == 'createpage' || $action == 'createtalk' ) {
2569                                 $msg = 'nocreatetext';
2570                         } elseif ( $action == 'upload' ) {
2571                                 $msg = 'uploadnologintext';
2572                         } else { # Read
2573                                 $msg = 'loginreqpagetext';
2574                                 $displayReturnto = Title::newMainPage();
2575                         }
2576
2577                         $query = [];
2578
2579                         if ( $returnto ) {
2580                                 $query['returnto'] = $returnto->getPrefixedText();
2581
2582                                 if ( !$request->wasPosted() ) {
2583                                         $returntoquery = $request->getValues();
2584                                         unset( $returntoquery['title'] );
2585                                         unset( $returntoquery['returnto'] );
2586                                         unset( $returntoquery['returntoquery'] );
2587                                         $query['returntoquery'] = wfArrayToCgi( $returntoquery );
2588                                 }
2589                         }
2590                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
2591                         $loginLink = $linkRenderer->makeKnownLink(
2592                                 SpecialPage::getTitleFor( 'Userlogin' ),
2593                                 $this->msg( 'loginreqlink' )->text(),
2594                                 [],
2595                                 $query
2596                         );
2597
2598                         $this->prepareErrorPage( $this->msg( 'loginreqtitle' ) );
2599                         $this->addHTML( $this->msg( $msg )->rawParams( $loginLink )->parse() );
2600
2601                         # Don't return to a page the user can't read otherwise
2602                         # we'll end up in a pointless loop
2603                         if ( $displayReturnto && $displayReturnto->userCan( 'read', $this->getUser() ) ) {
2604                                 $this->returnToMain( null, $displayReturnto );
2605                         }
2606                 } else {
2607                         $this->prepareErrorPage( $this->msg( 'permissionserrors' ) );
2608                         $this->addWikiText( $this->formatPermissionsErrorMessage( $errors, $action ) );
2609                 }
2610         }
2611
2612         /**
2613          * Display an error page indicating that a given version of MediaWiki is
2614          * required to use it
2615          *
2616          * @param mixed $version The version of MediaWiki needed to use the page
2617          */
2618         public function versionRequired( $version ) {
2619                 $this->prepareErrorPage( $this->msg( 'versionrequired', $version ) );
2620
2621                 $this->addWikiMsg( 'versionrequiredtext', $version );
2622                 $this->returnToMain();
2623         }
2624
2625         /**
2626          * Format a list of error messages
2627          *
2628          * @param array $errors Array of arrays returned by Title::getUserPermissionsErrors
2629          * @param string $action Action that was denied or null if unknown
2630          * @return string The wikitext error-messages, formatted into a list.
2631          */
2632         public function formatPermissionsErrorMessage( array $errors, $action = null ) {
2633                 if ( $action == null ) {
2634                         $text = $this->msg( 'permissionserrorstext', count( $errors ) )->plain() . "\n\n";
2635                 } else {
2636                         $action_desc = $this->msg( "action-$action" )->plain();
2637                         $text = $this->msg(
2638                                 'permissionserrorstext-withaction',
2639                                 count( $errors ),
2640                                 $action_desc
2641                         )->plain() . "\n\n";
2642                 }
2643
2644                 if ( count( $errors ) > 1 ) {
2645                         $text .= '<ul class="permissions-errors">' . "\n";
2646
2647                         foreach ( $errors as $error ) {
2648                                 $text .= '<li>';
2649                                 $text .= call_user_func_array( [ $this, 'msg' ], $error )->plain();
2650                                 $text .= "</li>\n";
2651                         }
2652                         $text .= '</ul>';
2653                 } else {
2654                         $text .= "<div class=\"permissions-errors\">\n" .
2655                                         call_user_func_array( [ $this, 'msg' ], reset( $errors ) )->plain() .
2656                                         "\n</div>";
2657                 }
2658
2659                 return $text;
2660         }
2661
2662         /**
2663          * Display a page stating that the Wiki is in read-only mode.
2664          * Should only be called after wfReadOnly() has returned true.
2665          *
2666          * Historically, this function was used to show the source of the page that the user
2667          * was trying to edit and _also_ permissions error messages. The relevant code was
2668          * moved into EditPage in 1.19 (r102024 / d83c2a431c2a) and removed here in 1.25.
2669          *
2670          * @deprecated since 1.25; throw the exception directly
2671          * @throws ReadOnlyError
2672          */
2673         public function readOnlyPage() {
2674                 if ( func_num_args() > 0 ) {
2675                         throw new MWException( __METHOD__ . ' no longer accepts arguments since 1.25.' );
2676                 }
2677
2678                 throw new ReadOnlyError;
2679         }
2680
2681         /**
2682          * Turn off regular page output and return an error response
2683          * for when rate limiting has triggered.
2684          *
2685          * @deprecated since 1.25; throw the exception directly
2686          */
2687         public function rateLimited() {
2688                 wfDeprecated( __METHOD__, '1.25' );
2689                 throw new ThrottledError;
2690         }
2691
2692         /**
2693          * Show a warning about replica DB lag
2694          *
2695          * If the lag is higher than $wgSlaveLagCritical seconds,
2696          * then the warning is a bit more obvious. If the lag is
2697          * lower than $wgSlaveLagWarning, then no warning is shown.
2698          *
2699          * @param int $lag Slave lag
2700          */
2701         public function showLagWarning( $lag ) {
2702                 $config = $this->getConfig();
2703                 if ( $lag >= $config->get( 'SlaveLagWarning' ) ) {
2704                         $lag = floor( $lag ); // floor to avoid nano seconds to display
2705                         $message = $lag < $config->get( 'SlaveLagCritical' )
2706                                 ? 'lag-warn-normal'
2707                                 : 'lag-warn-high';
2708                         $wrap = Html::rawElement( 'div', [ 'class' => "mw-{$message}" ], "\n$1\n" );
2709                         $this->wrapWikiMsg( "$wrap\n", [ $message, $this->getLanguage()->formatNum( $lag ) ] );
2710                 }
2711         }
2712
2713         public function showFatalError( $message ) {
2714                 $this->prepareErrorPage( $this->msg( 'internalerror' ) );
2715
2716                 $this->addHTML( $message );
2717         }
2718
2719         public function showUnexpectedValueError( $name, $val ) {
2720                 $this->showFatalError( $this->msg( 'unexpected', $name, $val )->text() );
2721         }
2722
2723         public function showFileCopyError( $old, $new ) {
2724                 $this->showFatalError( $this->msg( 'filecopyerror', $old, $new )->text() );
2725         }
2726
2727         public function showFileRenameError( $old, $new ) {
2728                 $this->showFatalError( $this->msg( 'filerenameerror', $old, $new )->text() );
2729         }
2730
2731         public function showFileDeleteError( $name ) {
2732                 $this->showFatalError( $this->msg( 'filedeleteerror', $name )->text() );
2733         }
2734
2735         public function showFileNotFoundError( $name ) {
2736                 $this->showFatalError( $this->msg( 'filenotfound', $name )->text() );
2737         }
2738
2739         /**
2740          * Add a "return to" link pointing to a specified title
2741          *
2742          * @param Title $title Title to link
2743          * @param array $query Query string parameters
2744          * @param string $text Text of the link (input is not escaped)
2745          * @param array $options Options array to pass to Linker
2746          */
2747         public function addReturnTo( $title, array $query = [], $text = null, $options = [] ) {
2748                 $linkRenderer = MediaWikiServices::getInstance()
2749                         ->getLinkRendererFactory()->createFromLegacyOptions( $options );
2750                 $link = $this->msg( 'returnto' )->rawParams(
2751                         $linkRenderer->makeLink( $title, $text, [], $query ) )->escaped();
2752                 $this->addHTML( "<p id=\"mw-returnto\">{$link}</p>\n" );
2753         }
2754
2755         /**
2756          * Add a "return to" link pointing to a specified title,
2757          * or the title indicated in the request, or else the main page
2758          *
2759          * @param mixed $unused
2760          * @param Title|string $returnto Title or String to return to
2761          * @param string $returntoquery Query string for the return to link
2762          */
2763         public function returnToMain( $unused = null, $returnto = null, $returntoquery = null ) {
2764                 if ( $returnto == null ) {
2765                         $returnto = $this->getRequest()->getText( 'returnto' );
2766                 }
2767
2768                 if ( $returntoquery == null ) {
2769                         $returntoquery = $this->getRequest()->getText( 'returntoquery' );
2770                 }
2771
2772                 if ( $returnto === '' ) {
2773                         $returnto = Title::newMainPage();
2774                 }
2775
2776                 if ( is_object( $returnto ) ) {
2777                         $titleObj = $returnto;
2778                 } else {
2779                         $titleObj = Title::newFromText( $returnto );
2780                 }
2781                 // We don't want people to return to external interwiki. That
2782                 // might potentially be used as part of a phishing scheme
2783                 if ( !is_object( $titleObj ) || $titleObj->isExternal() ) {
2784                         $titleObj = Title::newMainPage();
2785                 }
2786
2787                 $this->addReturnTo( $titleObj, wfCgiToArray( $returntoquery ) );
2788         }
2789
2790         private function getRlClientContext() {
2791                 if ( !$this->rlClientContext ) {
2792                         $query = ResourceLoader::makeLoaderQuery(
2793                                 [], // modules; not relevant
2794                                 $this->getLanguage()->getCode(),
2795                                 $this->getSkin()->getSkinName(),
2796                                 $this->getUser()->isLoggedIn() ? $this->getUser()->getName() : null,
2797                                 null, // version; not relevant
2798                                 ResourceLoader::inDebugMode(),
2799                                 null, // only; not relevant
2800                                 $this->isPrintable(),
2801                                 $this->getRequest()->getBool( 'handheld' )
2802                         );
2803                         $this->rlClientContext = new ResourceLoaderContext(
2804                                 $this->getResourceLoader(),
2805                                 new FauxRequest( $query )
2806                         );
2807                 }
2808                 return $this->rlClientContext;
2809         }
2810
2811         /**
2812          * Call this to freeze the module queue and JS config and create a formatter.
2813          *
2814          * Depending on the Skin, this may get lazy-initialised in either headElement() or
2815          * getBottomScripts(). See SkinTemplate::prepareQuickTemplate(). Calling this too early may
2816          * cause unexpected side-effects since disallowUserJs() may be called at any time to change
2817          * the module filters retroactively. Skins and extension hooks may also add modules until very
2818          * late in the request lifecycle.
2819          *
2820          * @return ResourceLoaderClientHtml
2821          */
2822         public function getRlClient() {
2823                 if ( !$this->rlClient ) {
2824                         $context = $this->getRlClientContext();
2825                         $rl = $this->getResourceLoader();
2826                         $this->addModules( [
2827                                 'user.options',
2828                                 'user.tokens',
2829                         ] );
2830                         $this->addModuleStyles( [
2831                                 'site.styles',
2832                                 'noscript',
2833                                 'user.styles',
2834                         ] );
2835                         $this->getSkin()->setupSkinUserCss( $this );
2836
2837                         // Prepare exempt modules for buildExemptModules()
2838                         $exemptGroups = [ 'site' => [], 'noscript' => [], 'private' => [], 'user' => [] ];
2839                         $exemptStates = [];
2840                         $moduleStyles = $this->getModuleStyles( /*filter*/ true );
2841
2842                         // Preload getTitleInfo for isKnownEmpty calls below and in ResourceLoaderClientHtml
2843                         // Separate user-specific batch for improved cache-hit ratio.
2844                         $userBatch = [ 'user.styles', 'user' ];
2845                         $siteBatch = array_diff( $moduleStyles, $userBatch );
2846                         $dbr = wfGetDB( DB_REPLICA );
2847                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $siteBatch );
2848                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $userBatch );
2849
2850                         // Filter out modules handled by buildExemptModules()
2851                         $moduleStyles = array_filter( $moduleStyles,
2852                                 function ( $name ) use ( $rl, $context, &$exemptGroups, &$exemptStates ) {
2853                                         $module = $rl->getModule( $name );
2854                                         if ( $module ) {
2855                                                 if ( $name === 'user.styles' && $this->isUserCssPreview() ) {
2856                                                         $exemptStates[$name] = 'ready';
2857                                                         // Special case in buildExemptModules()
2858                                                         return false;
2859                                                 }
2860                                                 $group = $module->getGroup();
2861                                                 if ( isset( $exemptGroups[$group] ) ) {
2862                                                         $exemptStates[$name] = 'ready';
2863                                                         if ( !$module->isKnownEmpty( $context ) ) {
2864                                                                 // E.g. Don't output empty <styles>
2865                                                                 $exemptGroups[$group][] = $name;
2866                                                         }
2867                                                         return false;
2868                                                 }
2869                                         }
2870                                         return true;
2871                                 }
2872                         );
2873                         $this->rlExemptStyleModules = $exemptGroups;
2874
2875                         $isUserModuleFiltered = !$this->filterModules( [ 'user' ] );
2876                         // If this page filters out 'user', makeResourceLoaderLink will drop it.
2877                         // Avoid indefinite "loading" state or untrue "ready" state (T145368).
2878                         if ( !$isUserModuleFiltered ) {
2879                                 // Manually handled by getBottomScripts()
2880                                 $userModule = $rl->getModule( 'user' );
2881                                 $userState = $userModule->isKnownEmpty( $context ) && !$this->isUserJsPreview()
2882                                         ? 'ready'
2883                                         : 'loading';
2884                                 $this->rlUserModuleState = $exemptStates['user'] = $userState;
2885                         }
2886
2887                         $rlClient = new ResourceLoaderClientHtml( $context, $this->getTarget() );
2888                         $rlClient->setConfig( $this->getJSVars() );
2889                         $rlClient->setModules( $this->getModules( /*filter*/ true ) );
2890                         $rlClient->setModuleStyles( $moduleStyles );
2891                         $rlClient->setModuleScripts( $this->getModuleScripts( /*filter*/ true ) );
2892                         $rlClient->setExemptStates( $exemptStates );
2893                         $this->rlClient = $rlClient;
2894                 }
2895                 return $this->rlClient;
2896         }
2897
2898         /**
2899          * @param Skin $sk The given Skin
2900          * @param bool $includeStyle Unused
2901          * @return string The doctype, opening "<html>", and head element.
2902          */
2903         public function headElement( Skin $sk, $includeStyle = true ) {
2904                 global $wgContLang;
2905
2906                 $userdir = $this->getLanguage()->getDir();
2907                 $sitedir = $wgContLang->getDir();
2908
2909                 $pieces = [];
2910                 $pieces[] = Html::htmlHeader( Sanitizer::mergeAttributes(
2911                         $this->getRlClient()->getDocumentAttributes(),
2912                         $sk->getHtmlElementAttributes()
2913                 ) );
2914                 $pieces[] = Html::openElement( 'head' );
2915
2916                 if ( $this->getHTMLTitle() == '' ) {
2917                         $this->setHTMLTitle( $this->msg( 'pagetitle', $this->getPageTitle() )->inContentLanguage() );
2918                 }
2919
2920                 if ( !Html::isXmlMimeType( $this->getConfig()->get( 'MimeType' ) ) ) {
2921                         // Add <meta charset="UTF-8">
2922                         // This should be before <title> since it defines the charset used by
2923                         // text including the text inside <title>.
2924                         // The spec recommends defining XHTML5's charset using the XML declaration
2925                         // instead of meta.
2926                         // Our XML declaration is output by Html::htmlHeader.
2927                         // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-content-type
2928                         // https://html.spec.whatwg.org/multipage/semantics.html#charset
2929                         $pieces[] = Html::element( 'meta', [ 'charset' => 'UTF-8' ] );
2930                 }
2931
2932                 $pieces[] = Html::element( 'title', null, $this->getHTMLTitle() );
2933                 $pieces[] = $this->getRlClient()->getHeadHtml();
2934                 $pieces[] = $this->buildExemptModules();
2935                 $pieces = array_merge( $pieces, array_values( $this->getHeadLinksArray() ) );
2936                 $pieces = array_merge( $pieces, array_values( $this->mHeadItems ) );
2937
2938                 // Use an IE conditional comment to serve the script only to old IE
2939                 $pieces[] = '<!--[if lt IE 9]>' .
2940                         ResourceLoaderClientHtml::makeLoad(
2941                                 ResourceLoaderContext::newDummyContext(),
2942                                 [ 'html5shiv' ],
2943                                 ResourceLoaderModule::TYPE_SCRIPTS,
2944                                 [ 'sync' => true ]
2945                         ) .
2946                         '<![endif]-->';
2947
2948                 $pieces[] = Html::closeElement( 'head' );
2949
2950                 $bodyClasses = $this->mAdditionalBodyClasses;
2951                 $bodyClasses[] = 'mediawiki';
2952
2953                 # Classes for LTR/RTL directionality support
2954                 $bodyClasses[] = $userdir;
2955                 $bodyClasses[] = "sitedir-$sitedir";
2956
2957                 $underline = $this->getUser()->getOption( 'underline' );
2958                 if ( $underline < 2 ) {
2959                         // The following classes can be used here:
2960                         // * mw-underline-always
2961                         // * mw-underline-never
2962                         $bodyClasses[] = 'mw-underline-' . ( $underline ? 'always' : 'never' );
2963                 }
2964
2965                 if ( $this->getLanguage()->capitalizeAllNouns() ) {
2966                         # A <body> class is probably not the best way to do this . . .
2967                         $bodyClasses[] = 'capitalize-all-nouns';
2968                 }
2969
2970                 // Parser feature migration class
2971                 // The idea is that this will eventually be removed, after the wikitext
2972                 // which requires it is cleaned up.
2973                 $bodyClasses[] = 'mw-hide-empty-elt';
2974
2975                 $bodyClasses[] = $sk->getPageClasses( $this->getTitle() );
2976                 $bodyClasses[] = 'skin-' . Sanitizer::escapeClass( $sk->getSkinName() );
2977                 $bodyClasses[] =
2978                         'action-' . Sanitizer::escapeClass( Action::getActionName( $this->getContext() ) );
2979
2980                 $bodyAttrs = [];
2981                 // While the implode() is not strictly needed, it's used for backwards compatibility
2982                 // (this used to be built as a string and hooks likely still expect that).
2983                 $bodyAttrs['class'] = implode( ' ', $bodyClasses );
2984
2985                 // Allow skins and extensions to add body attributes they need
2986                 $sk->addToBodyAttributes( $this, $bodyAttrs );
2987                 Hooks::run( 'OutputPageBodyAttributes', [ $this, $sk, &$bodyAttrs ] );
2988
2989                 $pieces[] = Html::openElement( 'body', $bodyAttrs );
2990
2991                 return self::combineWrappedStrings( $pieces );
2992         }
2993
2994         /**
2995          * Get a ResourceLoader object associated with this OutputPage
2996          *
2997          * @return ResourceLoader
2998          */
2999         public function getResourceLoader() {
3000                 if ( is_null( $this->mResourceLoader ) ) {
3001                         $this->mResourceLoader = new ResourceLoader(
3002                                 $this->getConfig(),
3003                                 LoggerFactory::getInstance( 'resourceloader' )
3004                         );
3005                 }
3006                 return $this->mResourceLoader;
3007         }
3008
3009         /**
3010          * Explicily load or embed modules on a page.
3011          *
3012          * @param array|string $modules One or more module names
3013          * @param string $only ResourceLoaderModule TYPE_ class constant
3014          * @param array $extraQuery [optional] Array with extra query parameters for the request
3015          * @return string|WrappedStringList HTML
3016          */
3017         public function makeResourceLoaderLink( $modules, $only, array $extraQuery = [] ) {
3018                 // Apply 'target' and 'origin' filters
3019                 $modules = $this->filterModules( (array)$modules, null, $only );
3020
3021                 return ResourceLoaderClientHtml::makeLoad(
3022                         $this->getRlClientContext(),
3023                         $modules,
3024                         $only,
3025                         $extraQuery
3026                 );
3027         }
3028
3029         /**
3030          * Combine WrappedString chunks and filter out empty ones
3031          *
3032          * @param array $chunks
3033          * @return string|WrappedStringList HTML
3034          */
3035         protected static function combineWrappedStrings( array $chunks ) {
3036                 // Filter out empty values
3037                 $chunks = array_filter( $chunks, 'strlen' );
3038                 return WrappedString::join( "\n", $chunks );
3039         }
3040
3041         private function isUserJsPreview() {
3042                 return $this->getConfig()->get( 'AllowUserJs' )
3043                         && $this->getTitle()
3044                         && $this->getTitle()->isJsSubpage()
3045                         && $this->userCanPreview();
3046         }
3047
3048         protected function isUserCssPreview() {
3049                 return $this->getConfig()->get( 'AllowUserCss' )
3050                         && $this->getTitle()
3051                         && $this->getTitle()->isCssSubpage()
3052                         && $this->userCanPreview();
3053         }
3054
3055         /**
3056          * JS stuff to put at the bottom of the `<body>`. These are modules with position 'bottom',
3057          * legacy scripts ($this->mScripts), and user JS.
3058          *
3059          * @return string|WrappedStringList HTML
3060          */
3061         public function getBottomScripts() {
3062                 $chunks = [];
3063                 $chunks[] = $this->getRlClient()->getBodyHtml();
3064
3065                 // Legacy non-ResourceLoader scripts
3066                 $chunks[] = $this->mScripts;
3067
3068                 // Exempt 'user' module
3069                 // - May need excludepages for live preview. (T28283)
3070                 // - Must use TYPE_COMBINED so its response is handled by mw.loader.implement() which
3071                 //   ensures execution is scheduled after the "site" module.
3072                 // - Don't load if module state is already resolved as "ready".
3073                 if ( $this->rlUserModuleState === 'loading' ) {
3074                         if ( $this->isUserJsPreview() ) {
3075                                 $chunks[] = $this->makeResourceLoaderLink( 'user', ResourceLoaderModule::TYPE_COMBINED,
3076                                         [ 'excludepage' => $this->getTitle()->getPrefixedDBkey() ]
3077                                 );
3078                                 $chunks[] = ResourceLoader::makeInlineScript(
3079                                         Xml::encodeJsCall( 'mw.loader.using', [
3080                                                 [ 'user', 'site' ],
3081                                                 new XmlJsCode(
3082                                                         'function () {'
3083                                                                 . Xml::encodeJsCall( '$.globalEval', [
3084                                                                         $this->getRequest()->getText( 'wpTextbox1' )
3085                                                                 ] )
3086                                                                 . '}'
3087                                                 )
3088                                         ] )
3089                                 );
3090                                 // FIXME: If the user is previewing, say, ./vector.js, his ./common.js will be loaded
3091                                 // asynchronously and may arrive *after* the inline script here. So the previewed code
3092                                 // may execute before ./common.js runs. Normally, ./common.js runs before ./vector.js.
3093                                 // Similarly, when previewing ./common.js and the user module does arrive first,
3094                                 // it will arrive without common.js and the inline script runs after.
3095                                 // Thus running common after the excluded subpage.
3096                         } else {
3097                                 // Load normally
3098                                 $chunks[] = $this->makeResourceLoaderLink( 'user', ResourceLoaderModule::TYPE_COMBINED );
3099                         }
3100                 }
3101
3102                 if ( $this->limitReportJSData ) {
3103                         $chunks[] = ResourceLoader::makeInlineScript(
3104                                 ResourceLoader::makeConfigSetScript(
3105                                         [ 'wgPageParseReport' => $this->limitReportJSData ]
3106                                 )
3107                         );
3108                 }
3109
3110                 return self::combineWrappedStrings( $chunks );
3111         }
3112
3113         /**
3114          * Get the javascript config vars to include on this page
3115          *
3116          * @return array Array of javascript config vars
3117          * @since 1.23
3118          */
3119         public function getJsConfigVars() {
3120                 return $this->mJsConfigVars;
3121         }
3122
3123         /**
3124          * Add one or more variables to be set in mw.config in JavaScript
3125          *
3126          * @param string|array $keys Key or array of key/value pairs
3127          * @param mixed $value [optional] Value of the configuration variable
3128          */
3129         public function addJsConfigVars( $keys, $value = null ) {
3130                 if ( is_array( $keys ) ) {
3131                         foreach ( $keys as $key => $value ) {
3132                                 $this->mJsConfigVars[$key] = $value;
3133                         }
3134                         return;
3135                 }
3136
3137                 $this->mJsConfigVars[$keys] = $value;
3138         }
3139
3140         /**
3141          * Get an array containing the variables to be set in mw.config in JavaScript.
3142          *
3143          * Do not add things here which can be evaluated in ResourceLoaderStartUpModule
3144          * - in other words, page-independent/site-wide variables (without state).
3145          * You will only be adding bloat to the html page and causing page caches to
3146          * have to be purged on configuration changes.
3147          * @return array
3148          */
3149         public function getJSVars() {
3150                 global $wgContLang;
3151
3152                 $curRevisionId = 0;
3153                 $articleId = 0;
3154                 $canonicalSpecialPageName = false; # T23115
3155
3156                 $title = $this->getTitle();
3157                 $ns = $title->getNamespace();
3158                 $canonicalNamespace = MWNamespace::exists( $ns )
3159                         ? MWNamespace::getCanonicalName( $ns )
3160                         : $title->getNsText();
3161
3162                 $sk = $this->getSkin();
3163                 // Get the relevant title so that AJAX features can use the correct page name
3164                 // when making API requests from certain special pages (T36972).
3165                 $relevantTitle = $sk->getRelevantTitle();
3166                 $relevantUser = $sk->getRelevantUser();
3167
3168                 if ( $ns == NS_SPECIAL ) {
3169                         list( $canonicalSpecialPageName, /*...*/ ) =
3170                                 SpecialPageFactory::resolveAlias( $title->getDBkey() );
3171                 } elseif ( $this->canUseWikiPage() ) {
3172                         $wikiPage = $this->getWikiPage();
3173                         $curRevisionId = $wikiPage->getLatest();
3174                         $articleId = $wikiPage->getId();
3175                 }
3176
3177                 $lang = $title->getPageViewLanguage();
3178
3179                 // Pre-process information
3180                 $separatorTransTable = $lang->separatorTransformTable();
3181                 $separatorTransTable = $separatorTransTable ? $separatorTransTable : [];
3182                 $compactSeparatorTransTable = [
3183                         implode( "\t", array_keys( $separatorTransTable ) ),
3184                         implode( "\t", $separatorTransTable ),
3185                 ];
3186                 $digitTransTable = $lang->digitTransformTable();
3187                 $digitTransTable = $digitTransTable ? $digitTransTable : [];
3188                 $compactDigitTransTable = [
3189                         implode( "\t", array_keys( $digitTransTable ) ),
3190                         implode( "\t", $digitTransTable ),
3191                 ];
3192
3193                 $user = $this->getUser();
3194
3195                 $vars = [
3196                         'wgCanonicalNamespace' => $canonicalNamespace,
3197                         'wgCanonicalSpecialPageName' => $canonicalSpecialPageName,
3198                         'wgNamespaceNumber' => $title->getNamespace(),
3199                         'wgPageName' => $title->getPrefixedDBkey(),
3200                         'wgTitle' => $title->getText(),
3201                         'wgCurRevisionId' => $curRevisionId,
3202                         'wgRevisionId' => (int)$this->getRevisionId(),
3203                         'wgArticleId' => $articleId,
3204                         'wgIsArticle' => $this->isArticle(),
3205                         'wgIsRedirect' => $title->isRedirect(),
3206                         'wgAction' => Action::getActionName( $this->getContext() ),
3207                         'wgUserName' => $user->isAnon() ? null : $user->getName(),
3208                         'wgUserGroups' => $user->getEffectiveGroups(),
3209                         'wgCategories' => $this->getCategories(),
3210                         'wgBreakFrames' => $this->getFrameOptions() == 'DENY',
3211                         'wgPageContentLanguage' => $lang->getCode(),
3212                         'wgPageContentModel' => $title->getContentModel(),
3213                         'wgSeparatorTransformTable' => $compactSeparatorTransTable,
3214                         'wgDigitTransformTable' => $compactDigitTransTable,
3215                         'wgDefaultDateFormat' => $lang->getDefaultDateFormat(),
3216                         'wgMonthNames' => $lang->getMonthNamesArray(),
3217                         'wgMonthNamesShort' => $lang->getMonthAbbreviationsArray(),
3218                         'wgRelevantPageName' => $relevantTitle->getPrefixedDBkey(),
3219                         'wgRelevantArticleId' => $relevantTitle->getArticleID(),
3220                         'wgRequestId' => WebRequest::getRequestId(),
3221                 ];
3222
3223                 if ( $user->isLoggedIn() ) {
3224                         $vars['wgUserId'] = $user->getId();
3225                         $vars['wgUserEditCount'] = $user->getEditCount();
3226                         $userReg = $user->getRegistration();
3227                         $vars['wgUserRegistration'] = $userReg ? wfTimestamp( TS_UNIX, $userReg ) * 1000 : null;
3228                         // Get the revision ID of the oldest new message on the user's talk
3229                         // page. This can be used for constructing new message alerts on
3230                         // the client side.
3231                         $vars['wgUserNewMsgRevisionId'] = $user->getNewMessageRevisionId();
3232                 }
3233
3234                 if ( $wgContLang->hasVariants() ) {
3235                         $vars['wgUserVariant'] = $wgContLang->getPreferredVariant();
3236                 }
3237                 // Same test as SkinTemplate
3238                 $vars['wgIsProbablyEditable'] = $title->quickUserCan( 'edit', $user )
3239                         && ( $title->exists() || $title->quickUserCan( 'create', $user ) );
3240
3241                 $vars['wgRelevantPageIsProbablyEditable'] = $relevantTitle
3242                         && $relevantTitle->quickUserCan( 'edit', $user )
3243                         && ( $relevantTitle->exists() || $relevantTitle->quickUserCan( 'create', $user ) );
3244
3245                 foreach ( $title->getRestrictionTypes() as $type ) {
3246                         $vars['wgRestriction' . ucfirst( $type )] = $title->getRestrictions( $type );
3247                 }
3248
3249                 if ( $title->isMainPage() ) {
3250                         $vars['wgIsMainPage'] = true;
3251                 }
3252
3253                 if ( $this->mRedirectedFrom ) {
3254                         $vars['wgRedirectedFrom'] = $this->mRedirectedFrom->getPrefixedDBkey();
3255                 }
3256
3257                 if ( $relevantUser ) {
3258                         $vars['wgRelevantUserName'] = $relevantUser->getName();
3259                 }
3260
3261                 // Allow extensions to add their custom variables to the mw.config map.
3262                 // Use the 'ResourceLoaderGetConfigVars' hook if the variable is not
3263                 // page-dependant but site-wide (without state).
3264                 // Alternatively, you may want to use OutputPage->addJsConfigVars() instead.
3265                 Hooks::run( 'MakeGlobalVariablesScript', [ &$vars, $this ] );
3266
3267                 // Merge in variables from addJsConfigVars last
3268                 return array_merge( $vars, $this->getJsConfigVars() );
3269         }
3270
3271         /**
3272          * To make it harder for someone to slip a user a fake
3273          * user-JavaScript or user-CSS preview, a random token
3274          * is associated with the login session. If it's not
3275          * passed back with the preview request, we won't render
3276          * the code.
3277          *
3278          * @return bool
3279          */
3280         public function userCanPreview() {
3281                 $request = $this->getRequest();
3282                 if (
3283                         $request->getVal( 'action' ) !== 'submit' ||
3284                         !$request->getCheck( 'wpPreview' ) ||
3285                         !$request->wasPosted()
3286                 ) {
3287                         return false;
3288                 }
3289
3290                 $user = $this->getUser();
3291
3292                 if ( !$user->isLoggedIn() ) {
3293                         // Anons have predictable edit tokens
3294                         return false;
3295                 }
3296                 if ( !$user->matchEditToken( $request->getVal( 'wpEditToken' ) ) ) {
3297                         return false;
3298                 }
3299
3300                 $title = $this->getTitle();
3301                 if ( !$title->isJsSubpage() && !$title->isCssSubpage() ) {
3302                         return false;
3303                 }
3304                 if ( !$title->isSubpageOf( $user->getUserPage() ) ) {
3305                         // Don't execute another user's CSS or JS on preview (T85855)
3306                         return false;
3307                 }
3308
3309                 $errors = $title->getUserPermissionsErrors( 'edit', $user );
3310                 if ( count( $errors ) !== 0 ) {
3311                         return false;
3312                 }
3313
3314                 return true;
3315         }
3316
3317         /**
3318          * @return array Array in format "link name or number => 'link html'".
3319          */
3320         public function getHeadLinksArray() {
3321                 global $wgVersion;
3322
3323                 $tags = [];
3324                 $config = $this->getConfig();
3325
3326                 $canonicalUrl = $this->mCanonicalUrl;
3327
3328                 $tags['meta-generator'] = Html::element( 'meta', [
3329                         'name' => 'generator',
3330                         'content' => "MediaWiki $wgVersion",
3331                 ] );
3332
3333                 if ( $config->get( 'ReferrerPolicy' ) !== false ) {
3334                         $tags['meta-referrer'] = Html::element( 'meta', [
3335                                 'name' => 'referrer',
3336                                 'content' => $config->get( 'ReferrerPolicy' )
3337                         ] );
3338                 }
3339
3340                 $p = "{$this->mIndexPolicy},{$this->mFollowPolicy}";
3341                 if ( $p !== 'index,follow' ) {
3342                         // http://www.robotstxt.org/wc/meta-user.html
3343                         // Only show if it's different from the default robots policy
3344                         $tags['meta-robots'] = Html::element( 'meta', [
3345                                 'name' => 'robots',
3346                                 'content' => $p,
3347                         ] );
3348                 }
3349
3350                 foreach ( $this->mMetatags as $tag ) {
3351                         if ( strncasecmp( $tag[0], 'http:', 5 ) === 0 ) {
3352                                 $a = 'http-equiv';
3353                                 $tag[0] = substr( $tag[0], 5 );
3354                         } elseif ( strncasecmp( $tag[0], 'og:', 3 ) === 0 ) {
3355                                 $a = 'property';
3356                         } else {
3357                                 $a = 'name';
3358                         }
3359                         $tagName = "meta-{$tag[0]}";
3360                         if ( isset( $tags[$tagName] ) ) {
3361                                 $tagName .= $tag[1];
3362                         }
3363                         $tags[$tagName] = Html::element( 'meta',
3364                                 [
3365                                         $a => $tag[0],
3366                                         'content' => $tag[1]
3367                                 ]
3368                         );
3369                 }
3370
3371                 foreach ( $this->mLinktags as $tag ) {
3372                         $tags[] = Html::element( 'link', $tag );
3373                 }
3374
3375                 # Universal edit button
3376                 if ( $config->get( 'UniversalEditButton' ) && $this->isArticleRelated() ) {
3377                         $user = $this->getUser();
3378                         if ( $this->getTitle()->quickUserCan( 'edit', $user )
3379                                 && ( $this->getTitle()->exists() ||
3380                                         $this->getTitle()->quickUserCan( 'create', $user ) )
3381                         ) {
3382                                 // Original UniversalEditButton
3383                                 $msg = $this->msg( 'edit' )->text();
3384                                 $tags['universal-edit-button'] = Html::element( 'link', [
3385                                         'rel' => 'alternate',
3386                                         'type' => 'application/x-wiki',
3387                                         'title' => $msg,
3388                                         'href' => $this->getTitle()->getEditURL(),
3389                                 ] );
3390                                 // Alternate edit link
3391                                 $tags['alternative-edit'] = Html::element( 'link', [
3392                                         'rel' => 'edit',
3393                                         'title' => $msg,
3394                                         'href' => $this->getTitle()->getEditURL(),
3395                                 ] );
3396                         }
3397                 }
3398
3399                 # Generally the order of the favicon and apple-touch-icon links
3400                 # should not matter, but Konqueror (3.5.9 at least) incorrectly
3401                 # uses whichever one appears later in the HTML source. Make sure
3402                 # apple-touch-icon is specified first to avoid this.
3403                 if ( $config->get( 'AppleTouchIcon' ) !== false ) {
3404                         $tags['apple-touch-icon'] = Html::element( 'link', [
3405                                 'rel' => 'apple-touch-icon',
3406                                 'href' => $config->get( 'AppleTouchIcon' )
3407                         ] );
3408                 }
3409
3410                 if ( $config->get( 'Favicon' ) !== false ) {
3411                         $tags['favicon'] = Html::element( 'link', [
3412                                 'rel' => 'shortcut icon',
3413                                 'href' => $config->get( 'Favicon' )
3414                         ] );
3415                 }
3416
3417                 # OpenSearch description link
3418                 $tags['opensearch'] = Html::element( 'link', [
3419                         'rel' => 'search',
3420                         'type' => 'application/opensearchdescription+xml',
3421                         'href' => wfScript( 'opensearch_desc' ),
3422                         'title' => $this->msg( 'opensearch-desc' )->inContentLanguage()->text(),
3423                 ] );
3424
3425                 if ( $config->get( 'EnableAPI' ) ) {
3426                         # Real Simple Discovery link, provides auto-discovery information
3427                         # for the MediaWiki API (and potentially additional custom API
3428                         # support such as WordPress or Twitter-compatible APIs for a
3429                         # blogging extension, etc)
3430                         $tags['rsd'] = Html::element( 'link', [
3431                                 'rel' => 'EditURI',
3432                                 'type' => 'application/rsd+xml',
3433                                 // Output a protocol-relative URL here if $wgServer is protocol-relative.
3434                                 // Whether RSD accepts relative or protocol-relative URLs is completely
3435                                 // undocumented, though.
3436                                 'href' => wfExpandUrl( wfAppendQuery(
3437                                         wfScript( 'api' ),
3438                                         [ 'action' => 'rsd' ] ),
3439                                         PROTO_RELATIVE
3440                                 ),
3441                         ] );
3442                 }
3443
3444                 # Language variants
3445                 if ( !$config->get( 'DisableLangConversion' ) ) {
3446                         $lang = $this->getTitle()->getPageLanguage();
3447                         if ( $lang->hasVariants() ) {
3448                                 $variants = $lang->getVariants();
3449                                 foreach ( $variants as $variant ) {
3450                                         $tags["variant-$variant"] = Html::element( 'link', [
3451                                                 'rel' => 'alternate',
3452                                                 'hreflang' => LanguageCode::bcp47( $variant ),
3453                                                 'href' => $this->getTitle()->getLocalURL(
3454                                                         [ 'variant' => $variant ] )
3455                                                 ]
3456                                         );
3457                                 }
3458                                 # x-default link per https://support.google.com/webmasters/answer/189077?hl=en
3459                                 $tags["variant-x-default"] = Html::element( 'link', [
3460                                         'rel' => 'alternate',
3461                                         'hreflang' => 'x-default',
3462                                         'href' => $this->getTitle()->getLocalURL() ] );
3463                         }
3464                 }
3465
3466                 # Copyright
3467                 if ( $this->copyrightUrl !== null ) {
3468                         $copyright = $this->copyrightUrl;
3469                 } else {
3470                         $copyright = '';
3471                         if ( $config->get( 'RightsPage' ) ) {
3472                                 $copy = Title::newFromText( $config->get( 'RightsPage' ) );
3473
3474                                 if ( $copy ) {
3475                                         $copyright = $copy->getLocalURL();
3476                                 }
3477                         }
3478
3479                         if ( !$copyright && $config->get( 'RightsUrl' ) ) {
3480                                 $copyright = $config->get( 'RightsUrl' );
3481                         }
3482                 }
3483
3484                 if ( $copyright ) {
3485                         $tags['copyright'] = Html::element( 'link', [
3486                                 'rel' => 'license',
3487                                 'href' => $copyright ]
3488                         );
3489                 }
3490
3491                 # Feeds
3492                 if ( $config->get( 'Feed' ) ) {
3493                         $feedLinks = [];
3494
3495                         foreach ( $this->getSyndicationLinks() as $format => $link ) {
3496                                 # Use the page name for the title.  In principle, this could
3497                                 # lead to issues with having the same name for different feeds
3498                                 # corresponding to the same page, but we can't avoid that at
3499                                 # this low a level.
3500
3501                                 $feedLinks[] = $this->feedLink(
3502                                         $format,
3503                                         $link,
3504                                         # Used messages: 'page-rss-feed' and 'page-atom-feed' (for an easier grep)
3505                                         $this->msg(
3506                                                 "page-{$format}-feed", $this->getTitle()->getPrefixedText()
3507                                         )->text()
3508                                 );
3509                         }
3510
3511                         # Recent changes feed should appear on every page (except recentchanges,
3512                         # that would be redundant). Put it after the per-page feed to avoid
3513                         # changing existing behavior. It's still available, probably via a
3514                         # menu in your browser. Some sites might have a different feed they'd
3515                         # like to promote instead of the RC feed (maybe like a "Recent New Articles"
3516                         # or "Breaking news" one). For this, we see if $wgOverrideSiteFeed is defined.
3517                         # If so, use it instead.
3518                         $sitename = $config->get( 'Sitename' );
3519                         if ( $config->get( 'OverrideSiteFeed' ) ) {
3520                                 foreach ( $config->get( 'OverrideSiteFeed' ) as $type => $feedUrl ) {
3521                                         // Note, this->feedLink escapes the url.
3522                                         $feedLinks[] = $this->feedLink(
3523                                                 $type,
3524                                                 $feedUrl,
3525                                                 $this->msg( "site-{$type}-feed", $sitename )->text()
3526                                         );
3527                                 }
3528                         } elseif ( !$this->getTitle()->isSpecial( 'Recentchanges' ) ) {
3529                                 $rctitle = SpecialPage::getTitleFor( 'Recentchanges' );
3530                                 foreach ( $config->get( 'AdvertisedFeedTypes' ) as $format ) {
3531                                         $feedLinks[] = $this->feedLink(
3532                                                 $format,
3533                                                 $rctitle->getLocalURL( [ 'feed' => $format ] ),
3534                                                 # For grep: 'site-rss-feed', 'site-atom-feed'
3535                                                 $this->msg( "site-{$format}-feed", $sitename )->text()
3536                                         );
3537                                 }
3538                         }
3539
3540                         # Allow extensions to change the list pf feeds. This hook is primarily for changing,
3541                         # manipulating or removing existing feed tags. If you want to add new feeds, you should
3542                         # use OutputPage::addFeedLink() instead.
3543                         Hooks::run( 'AfterBuildFeedLinks', [ &$feedLinks ] );
3544
3545                         $tags += $feedLinks;
3546                 }
3547
3548                 # Canonical URL
3549                 if ( $config->get( 'EnableCanonicalServerLink' ) ) {
3550                         if ( $canonicalUrl !== false ) {
3551                                 $canonicalUrl = wfExpandUrl( $canonicalUrl, PROTO_CANONICAL );
3552                         } else {
3553                                 if ( $this->isArticleRelated() ) {
3554                                         // This affects all requests where "setArticleRelated" is true. This is
3555                                         // typically all requests that show content (query title, curid, oldid, diff),
3556                                         // and all wikipage actions (edit, delete, purge, info, history etc.).
3557                                         // It does not apply to File pages and Special pages.
3558                                         // 'history' and 'info' actions address page metadata rather than the page
3559                                         // content itself, so they may not be canonicalized to the view page url.
3560                                         // TODO: this ought to be better encapsulated in the Action class.
3561                                         $action = Action::getActionName( $this->getContext() );
3562                                         if ( in_array( $action, [ 'history', 'info' ] ) ) {
3563                                                 $query = "action={$action}";
3564                                         } else {
3565                                                 $query = '';
3566                                         }
3567                                         $canonicalUrl = $this->getTitle()->getCanonicalURL( $query );
3568                                 } else {
3569                                         $reqUrl = $this->getRequest()->getRequestURL();
3570                                         $canonicalUrl = wfExpandUrl( $reqUrl, PROTO_CANONICAL );
3571                                 }
3572                         }
3573                 }
3574                 if ( $canonicalUrl !== false ) {
3575                         $tags[] = Html::element( 'link', [
3576                                 'rel' => 'canonical',
3577                                 'href' => $canonicalUrl
3578                         ] );
3579                 }
3580
3581                 return $tags;
3582         }
3583
3584         /**
3585          * Generate a "<link rel/>" for a feed.
3586          *
3587          * @param string $type Feed type
3588          * @param string $url URL to the feed
3589          * @param string $text Value of the "title" attribute
3590          * @return string HTML fragment
3591          */
3592         private function feedLink( $type, $url, $text ) {
3593                 return Html::element( 'link', [
3594                         'rel' => 'alternate',
3595                         'type' => "application/$type+xml",
3596                         'title' => $text,
3597                         'href' => $url ]
3598                 );
3599         }
3600
3601         /**
3602          * Add a local or specified stylesheet, with the given media options.
3603          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3604          *
3605          * @param string $style URL to the file
3606          * @param string $media To specify a media type, 'screen', 'printable', 'handheld' or any.
3607          * @param string $condition For IE conditional comments, specifying an IE version
3608          * @param string $dir Set to 'rtl' or 'ltr' for direction-specific sheets
3609          */
3610         public function addStyle( $style, $media = '', $condition = '', $dir = '' ) {
3611                 $options = [];
3612                 if ( $media ) {
3613                         $options['media'] = $media;
3614                 }
3615                 if ( $condition ) {
3616                         $options['condition'] = $condition;
3617                 }
3618                 if ( $dir ) {
3619                         $options['dir'] = $dir;
3620                 }
3621                 $this->styles[$style] = $options;
3622         }
3623
3624         /**
3625          * Adds inline CSS styles
3626          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3627          *
3628          * @param mixed $style_css Inline CSS
3629          * @param string $flip Set to 'flip' to flip the CSS if needed
3630          */
3631         public function addInlineStyle( $style_css, $flip = 'noflip' ) {
3632                 if ( $flip === 'flip' && $this->getLanguage()->isRTL() ) {
3633                         # If wanted, and the interface is right-to-left, flip the CSS
3634                         $style_css = CSSJanus::transform( $style_css, true, false );
3635                 }
3636                 $this->mInlineStyles .= Html::inlineStyle( $style_css );
3637         }
3638
3639         /**
3640          * Build exempt modules and legacy non-ResourceLoader styles.
3641          *
3642          * @return string|WrappedStringList HTML
3643          */
3644         protected function buildExemptModules() {
3645                 global $wgContLang;
3646
3647                 $chunks = [];
3648                 // Things that go after the ResourceLoaderDynamicStyles marker
3649                 $append = [];
3650
3651                 // Exempt 'user' styles module (may need 'excludepages' for live preview)
3652                 if ( $this->isUserCssPreview() ) {
3653                         $append[] = $this->makeResourceLoaderLink(
3654                                 'user.styles',
3655                                 ResourceLoaderModule::TYPE_STYLES,
3656                                 [ 'excludepage' => $this->getTitle()->getPrefixedDBkey() ]
3657                         );
3658
3659                         // Load the previewed CSS. Janus it if needed.
3660                         // User-supplied CSS is assumed to in the wiki's content language.
3661                         $previewedCSS = $this->getRequest()->getText( 'wpTextbox1' );
3662                         if ( $this->getLanguage()->getDir() !== $wgContLang->getDir() ) {
3663                                 $previewedCSS = CSSJanus::transform( $previewedCSS, true, false );
3664                         }
3665                         $append[] = Html::inlineStyle( $previewedCSS );
3666                 }
3667
3668                 // We want site, private and user styles to override dynamically added styles from
3669                 // general modules, but we want dynamically added styles to override statically added
3670                 // style modules. So the order has to be:
3671                 // - page style modules (formatted by ResourceLoaderClientHtml::getHeadHtml())
3672                 // - dynamically loaded styles (added by mw.loader before ResourceLoaderDynamicStyles)
3673                 // - ResourceLoaderDynamicStyles marker
3674                 // - site/private/user styles
3675
3676                 // Add legacy styles added through addStyle()/addInlineStyle() here
3677                 $chunks[] = implode( '', $this->buildCssLinksArray() ) . $this->mInlineStyles;
3678
3679                 $chunks[] = Html::element(
3680                         'meta',
3681                         [ 'name' => 'ResourceLoaderDynamicStyles', 'content' => '' ]
3682                 );
3683
3684                 $separateReq = [ 'site.styles', 'user.styles' ];
3685                 foreach ( $this->rlExemptStyleModules as $group => $moduleNames ) {
3686                         // Combinable modules
3687                         $chunks[] = $this->makeResourceLoaderLink(
3688                                 array_diff( $moduleNames, $separateReq ),
3689                                 ResourceLoaderModule::TYPE_STYLES
3690                         );
3691
3692                         foreach ( array_intersect( $moduleNames, $separateReq ) as $name ) {
3693                                 // These require their own dedicated request in order to support "@import"
3694                                 // syntax, which is incompatible with concatenation. (T147667, T37562)
3695                                 $chunks[] = $this->makeResourceLoaderLink( $name,
3696                                         ResourceLoaderModule::TYPE_STYLES
3697                                 );
3698                         }
3699                 }
3700
3701                 return self::combineWrappedStrings( array_merge( $chunks, $append ) );
3702         }
3703
3704         /**
3705          * @return array
3706          */
3707         public function buildCssLinksArray() {
3708                 $links = [];
3709
3710                 // Add any extension CSS
3711                 foreach ( $this->mExtStyles as $url ) {
3712                         $this->addStyle( $url );
3713                 }
3714                 $this->mExtStyles = [];
3715
3716                 foreach ( $this->styles as $file => $options ) {
3717                         $link = $this->styleLink( $file, $options );
3718                         if ( $link ) {
3719                                 $links[$file] = $link;
3720                         }
3721                 }
3722                 return $links;
3723         }
3724
3725         /**
3726          * Generate \<link\> tags for stylesheets
3727          *
3728          * @param string $style URL to the file
3729          * @param array $options Option, can contain 'condition', 'dir', 'media' keys
3730          * @return string HTML fragment
3731          */
3732         protected function styleLink( $style, array $options ) {
3733                 if ( isset( $options['dir'] ) ) {
3734                         if ( $this->getLanguage()->getDir() != $options['dir'] ) {
3735                                 return '';
3736                         }
3737                 }
3738
3739                 if ( isset( $options['media'] ) ) {
3740                         $media = self::transformCssMedia( $options['media'] );
3741                         if ( is_null( $media ) ) {
3742                                 return '';
3743                         }
3744                 } else {
3745                         $media = 'all';
3746                 }
3747
3748                 if ( substr( $style, 0, 1 ) == '/' ||
3749                         substr( $style, 0, 5 ) == 'http:' ||
3750                         substr( $style, 0, 6 ) == 'https:' ) {
3751                         $url = $style;
3752                 } else {
3753                         $config = $this->getConfig();
3754                         $url = $config->get( 'StylePath' ) . '/' . $style . '?' .
3755                                 $config->get( 'StyleVersion' );
3756                 }
3757
3758                 $link = Html::linkedStyle( $url, $media );
3759
3760                 if ( isset( $options['condition'] ) ) {
3761                         $condition = htmlspecialchars( $options['condition'] );
3762                         $link = "<!--[if $condition]>$link<![endif]-->";
3763                 }
3764                 return $link;
3765         }
3766
3767         /**
3768          * Transform path to web-accessible static resource.
3769          *
3770          * This is used to add a validation hash as query string.
3771          * This aids various behaviors:
3772          *
3773          * - Put long Cache-Control max-age headers on responses for improved
3774          *   cache performance.
3775          * - Get the correct version of a file as expected by the current page.
3776          * - Instantly get the updated version of a file after deployment.
3777          *
3778          * Avoid using this for urls included in HTML as otherwise clients may get different
3779          * versions of a resource when navigating the site depending on when the page was cached.
3780          * If changes to the url propagate, this is not a problem (e.g. if the url is in
3781          * an external stylesheet).
3782          *
3783          * @since 1.27
3784          * @param Config $config
3785          * @param string $path Path-absolute URL to file (from document root, must start with "/")
3786          * @return string URL
3787          */
3788         public static function transformResourcePath( Config $config, $path ) {
3789                 global $IP;
3790
3791                 $localDir = $IP;
3792                 $remotePathPrefix = $config->get( 'ResourceBasePath' );
3793                 if ( $remotePathPrefix === '' ) {
3794                         // The configured base path is required to be empty string for
3795                         // wikis in the domain root
3796                         $remotePath = '/';
3797                 } else {
3798                         $remotePath = $remotePathPrefix;
3799                 }
3800                 if ( strpos( $path, $remotePath ) !== 0 || substr( $path, 0, 2 ) === '//' ) {
3801                         // - Path is outside wgResourceBasePath, ignore.
3802                         // - Path is protocol-relative. Fixes T155310. Not supported by RelPath lib.
3803                         return $path;
3804                 }
3805                 // For files in resources, extensions/ or skins/, ResourceBasePath is preferred here.
3806                 // For other misc files in $IP, we'll fallback to that as well. There is, however, a fourth
3807                 // supported dir/path pair in the configuration (wgUploadDirectory, wgUploadPath)
3808                 // which is not expected to be in wgResourceBasePath on CDNs. (T155146)
3809                 $uploadPath = $config->get( 'UploadPath' );
3810                 if ( strpos( $path, $uploadPath ) === 0 ) {
3811                         $localDir = $config->get( 'UploadDirectory' );
3812                         $remotePathPrefix = $remotePath = $uploadPath;
3813                 }
3814
3815                 $path = RelPath\getRelativePath( $path, $remotePath );
3816                 return self::transformFilePath( $remotePathPrefix, $localDir, $path );
3817         }
3818
3819         /**
3820          * Utility method for transformResourceFilePath().
3821          *
3822          * Caller is responsible for ensuring the file exists. Emits a PHP warning otherwise.
3823          *
3824          * @since 1.27
3825          * @param string $remotePathPrefix URL path prefix that points to $localPath
3826          * @param string $localPath File directory exposed at $remotePath
3827          * @param string $file Path to target file relative to $localPath
3828          * @return string URL
3829          */
3830         public static function transformFilePath( $remotePathPrefix, $localPath, $file ) {
3831                 $hash = md5_file( "$localPath/$file" );
3832                 if ( $hash === false ) {
3833                         wfLogWarning( __METHOD__ . ": Failed to hash $localPath/$file" );
3834                         $hash = '';
3835                 }
3836                 return "$remotePathPrefix/$file?" . substr( $hash, 0, 5 );
3837         }
3838
3839         /**
3840          * Transform "media" attribute based on request parameters
3841          *
3842          * @param string $media Current value of the "media" attribute
3843          * @return string Modified value of the "media" attribute, or null to skip
3844          * this stylesheet
3845          */
3846         public static function transformCssMedia( $media ) {
3847                 global $wgRequest;
3848
3849                 // https://www.w3.org/TR/css3-mediaqueries/#syntax
3850                 $screenMediaQueryRegex = '/^(?:only\s+)?screen\b/i';
3851
3852                 // Switch in on-screen display for media testing
3853                 $switches = [
3854                         'printable' => 'print',
3855                         'handheld' => 'handheld',
3856                 ];
3857                 foreach ( $switches as $switch => $targetMedia ) {
3858                         if ( $wgRequest->getBool( $switch ) ) {
3859                                 if ( $media == $targetMedia ) {
3860                                         $media = '';
3861                                 } elseif ( preg_match( $screenMediaQueryRegex, $media ) === 1 ) {
3862                                         /* This regex will not attempt to understand a comma-separated media_query_list
3863                                          *
3864                                          * Example supported values for $media:
3865                                          * 'screen', 'only screen', 'screen and (min-width: 982px)' ),
3866                                          * Example NOT supported value for $media:
3867                                          * '3d-glasses, screen, print and resolution > 90dpi'
3868                                          *
3869                                          * If it's a print request, we never want any kind of screen stylesheets
3870                                          * If it's a handheld request (currently the only other choice with a switch),
3871                                          * we don't want simple 'screen' but we might want screen queries that
3872                                          * have a max-width or something, so we'll pass all others on and let the
3873                                          * client do the query.
3874                                          */
3875                                         if ( $targetMedia == 'print' || $media == 'screen' ) {
3876                                                 return null;
3877                                         }
3878                                 }
3879                         }
3880                 }
3881
3882                 return $media;
3883         }
3884
3885         /**
3886          * Add a wikitext-formatted message to the output.
3887          * This is equivalent to:
3888          *
3889          *    $wgOut->addWikiText( wfMessage( ... )->plain() )
3890          */
3891         public function addWikiMsg( /*...*/ ) {
3892                 $args = func_get_args();
3893                 $name = array_shift( $args );
3894                 $this->addWikiMsgArray( $name, $args );
3895         }
3896
3897         /**
3898          * Add a wikitext-formatted message to the output.
3899          * Like addWikiMsg() except the parameters are taken as an array
3900          * instead of a variable argument list.
3901          *
3902          * @param string $name
3903          * @param array $args
3904          */
3905         public function addWikiMsgArray( $name, $args ) {
3906                 $this->addHTML( $this->msg( $name, $args )->parseAsBlock() );
3907         }
3908
3909         /**
3910          * This function takes a number of message/argument specifications, wraps them in
3911          * some overall structure, and then parses the result and adds it to the output.
3912          *
3913          * In the $wrap, $1 is replaced with the first message, $2 with the second,
3914          * and so on. The subsequent arguments may be either
3915          * 1) strings, in which case they are message names, or
3916          * 2) arrays, in which case, within each array, the first element is the message
3917          *    name, and subsequent elements are the parameters to that message.
3918          *
3919          * Don't use this for messages that are not in the user's interface language.
3920          *
3921          * For example:
3922          *
3923          *    $wgOut->wrapWikiMsg( "<div class='error'>\n$1\n</div>", 'some-error' );
3924          *
3925          * Is equivalent to:
3926          *
3927          *    $wgOut->addWikiText( "<div class='error'>\n"
3928          *        . wfMessage( 'some-error' )->plain() . "\n</div>" );
3929          *
3930          * The newline after the opening div is needed in some wikitext. See T21226.
3931          *
3932          * @param string $wrap
3933          */
3934         public function wrapWikiMsg( $wrap /*, ...*/ ) {
3935                 $msgSpecs = func_get_args();
3936                 array_shift( $msgSpecs );
3937                 $msgSpecs = array_values( $msgSpecs );
3938                 $s = $wrap;
3939                 foreach ( $msgSpecs as $n => $spec ) {
3940                         if ( is_array( $spec ) ) {
3941                                 $args = $spec;
3942                                 $name = array_shift( $args );
3943                                 if ( isset( $args['options'] ) ) {
3944                                         unset( $args['options'] );
3945                                         wfDeprecated(
3946                                                 'Adding "options" to ' . __METHOD__ . ' is no longer supported',
3947                                                 '1.20'
3948                                         );
3949                                 }
3950                         } else {
3951                                 $args = [];
3952                                 $name = $spec;
3953                         }
3954                         $s = str_replace( '$' . ( $n + 1 ), $this->msg( $name, $args )->plain(), $s );
3955                 }
3956                 $this->addWikiText( $s );
3957         }
3958
3959         /**
3960          * Whether the output has a table of contents
3961          * @return bool
3962          * @since 1.22
3963          */
3964         public function isTOCEnabled() {
3965                 return $this->mEnableTOC;
3966         }
3967
3968         /**
3969          * Enables/disables section edit links, doesn't override __NOEDITSECTION__
3970          * @param bool $flag
3971          * @since 1.23
3972          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
3973          */
3974         public function enableSectionEditLinks( $flag = true ) {
3975                 $this->mEnableSectionEditLinks = $flag;
3976         }
3977
3978         /**
3979          * @return bool
3980          * @since 1.23
3981          * @deprecated since 1.31, use $poOptions to addParserOutput() instead.
3982          */
3983         public function sectionEditLinksEnabled() {
3984                 return $this->mEnableSectionEditLinks;
3985         }
3986
3987         /**
3988          * Helper function to setup the PHP implementation of OOUI to use in this request.
3989          *
3990          * @since 1.26
3991          * @param String $skinName The Skin name to determine the correct OOUI theme
3992          * @param String $dir Language direction
3993          */
3994         public static function setupOOUI( $skinName = 'default', $dir = 'ltr' ) {
3995                 $themes = ResourceLoaderOOUIModule::getSkinThemeMap();
3996                 $theme = isset( $themes[$skinName] ) ? $themes[$skinName] : $themes['default'];
3997                 // For example, 'OOUI\WikimediaUITheme'.
3998                 $themeClass = "OOUI\\{$theme}Theme";
3999                 OOUI\Theme::setSingleton( new $themeClass() );
4000                 OOUI\Element::setDefaultDir( $dir );
4001         }
4002
4003         /**
4004          * Add ResourceLoader module styles for OOUI and set up the PHP implementation of it for use with
4005          * MediaWiki and this OutputPage instance.
4006          *
4007          * @since 1.25
4008          */
4009         public function enableOOUI() {
4010                 self::setupOOUI(
4011                         strtolower( $this->getSkin()->getSkinName() ),
4012                         $this->getLanguage()->getDir()
4013                 );
4014                 $this->addModuleStyles( [
4015                         'oojs-ui-core.styles',
4016                         'oojs-ui.styles.indicators',
4017                         'oojs-ui.styles.textures',
4018                         'mediawiki.widgets.styles',
4019                         'oojs-ui.styles.icons-content',
4020                         'oojs-ui.styles.icons-alerts',
4021                         'oojs-ui.styles.icons-interactions',
4022                 ] );
4023         }
4024
4025         /**
4026          * Add Link headers for preloading the wiki's logo.
4027          *
4028          * @since 1.26
4029          */
4030         protected function addLogoPreloadLinkHeaders() {
4031                 $logo = ResourceLoaderSkinModule::getLogo( $this->getConfig() );
4032
4033                 $tags = [];
4034                 $logosPerDppx = [];
4035                 $logos = [];
4036
4037                 if ( !is_array( $logo ) ) {
4038                         // No media queries required if we only have one variant
4039                         $this->addLinkHeader( '<' . $logo . '>;rel=preload;as=image' );
4040                         return;
4041                 }
4042
4043                 if ( isset( $logo['svg'] ) ) {
4044                         // No media queries required if we only have a 1x and svg variant
4045                         // because all preload-capable browsers support SVGs
4046                         $this->addLinkHeader( '<' . $logo['svg'] . '>;rel=preload;as=image' );
4047                         return;
4048                 }
4049
4050                 foreach ( $logo as $dppx => $src ) {
4051                         // Keys are in this format: "1.5x"
4052                         $dppx = substr( $dppx, 0, -1 );
4053                         $logosPerDppx[$dppx] = $src;
4054                 }
4055
4056                 // Because PHP can't have floats as array keys
4057                 uksort( $logosPerDppx, function ( $a , $b ) {
4058                         $a = floatval( $a );
4059                         $b = floatval( $b );
4060
4061                         if ( $a == $b ) {
4062                                 return 0;
4063                         }
4064                         // Sort from smallest to largest (e.g. 1x, 1.5x, 2x)
4065                         return ( $a < $b ) ? -1 : 1;
4066                 } );
4067
4068                 foreach ( $logosPerDppx as $dppx => $src ) {
4069                         $logos[] = [ 'dppx' => $dppx, 'src' => $src ];
4070                 }
4071
4072                 $logosCount = count( $logos );
4073                 // Logic must match ResourceLoaderSkinModule:
4074                 // - 1x applies to resolution < 1.5dppx
4075                 // - 1.5x applies to resolution >= 1.5dppx && < 2dppx
4076                 // - 2x applies to resolution >= 2dppx
4077                 // Note that min-resolution and max-resolution are both inclusive.
4078                 for ( $i = 0; $i < $logosCount; $i++ ) {
4079                         if ( $i === 0 ) {
4080                                 // Smallest dppx
4081                                 // min-resolution is ">=" (larger than or equal to)
4082                                 // "not min-resolution" is essentially "<"
4083                                 $media_query = 'not all and (min-resolution: ' . $logos[ 1 ]['dppx'] . 'dppx)';
4084                         } elseif ( $i !== $logosCount - 1 ) {
4085                                 // In between
4086                                 // Media query expressions can only apply "not" to the entire expression
4087                                 // (e.g. can't express ">= 1.5 and not >= 2).
4088                                 // Workaround: Use <= 1.9999 in place of < 2.
4089                                 $upper_bound = floatval( $logos[ $i + 1 ]['dppx'] ) - 0.000001;
4090                                 $media_query = '(min-resolution: ' . $logos[ $i ]['dppx'] .
4091                                         'dppx) and (max-resolution: ' . $upper_bound . 'dppx)';
4092                         } else {
4093                                 // Largest dppx
4094                                 $media_query = '(min-resolution: ' . $logos[ $i ]['dppx'] . 'dppx)';
4095                         }
4096
4097                         $this->addLinkHeader(
4098                                 '<' . $logos[$i]['src'] . '>;rel=preload;as=image;media=' . $media_query
4099                         );
4100                 }
4101         }
4102 }