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\Session\SessionManager;
  25 use WrappedString\WrappedString;
  26
  27 /**
  28  * This class should be covered by a general architecture document which does
  29  * not exist as of January 2011.  This is one of the Core classes and should
  30  * be read at least once by any new developers.
  31  *
  32  * This class is used to prepare the final rendering. A skin is then
  33  * applied to the output parameters (links, javascript, html, categories ...).
  34  *
  35  * @todo FIXME: Another class handles sending the whole page to the client.
  36  *
  37  * Some comments comes from a pairing session between Zak Greant and Antoine Musso
  38  * in November 2010.
  39  *
  40  * @todo document
  41  */
  42 class OutputPage extends ContextSource {
  43         /** @var array Should be private. Used with addMeta() which adds "<meta>" */
  44         protected $mMetatags = [];
  45
  46         /** @var array */
  47         protected $mLinktags = [];
  48
  49         /** @var bool */
  50         protected $mCanonicalUrl = false;
  51
  52         /**
  53          * @var array Additional stylesheets. Looks like this is for extensions.
  54          *   Might be replaced by ResourceLoader.
  55          */
  56         protected $mExtStyles = [];
  57
  58         /**
  59          * @var string Should be private - has getter and setter. Contains
  60          *   the HTML title */
  61         public $mPagetitle = '';
  62
  63         /**
  64          * @var string Contains all of the "<body>" content. Should be private we
  65          *   got set/get accessors and the append() method.
  66          */
  67         public $mBodytext = '';
  68
  69         /**
  70          * Holds the debug lines that will be output as comments in page source if
  71          * $wgDebugComments is enabled. See also $wgShowDebug.
  72          * @deprecated since 1.20; use MWDebug class instead.
  73          */
  74         public $mDebugtext = '';
  75
  76         /** @var string Stores contents of "<title>" tag */
  77         private $mHTMLtitle = '';
  78
  79         /**
  80          * @var bool Is the displayed content related to the source of the
  81          *   corresponding wiki article.
  82          */
  83         private $mIsarticle = false;
  84
  85         /** @var bool Stores "article flag" toggle. */
  86         private $mIsArticleRelated = true;
  87
  88         /**
  89          * @var bool We have to set isPrintable(). Some pages should
  90          * never be printed (ex: redirections).
  91          */
  92         private $mPrintable = false;
  93
  94         /**
  95          * @var array Contains the page subtitle. Special pages usually have some
  96          *   links here. Don't confuse with site subtitle added by skins.
  97          */
  98         private $mSubtitle = [];
  99
 100         /** @var string */
 101         public $mRedirect = '';
 102
 103         /** @var int */
 104         protected $mStatusCode;
 105
 106         /**
 107          * @var string Variable mLastModified and mEtag are used for sending cache control.
 108          *   The whole caching system should probably be moved into its own class.
 109          */
 110         protected $mLastModified = '';
 111
 112         /**
 113          * Contains an HTTP Entity Tags (see RFC 2616 section 3.13) which is used
 114          * as a unique identifier for the content. It is later used by the client
 115          * to compare its cached version with the server version. Client sends
 116          * headers If-Match and If-None-Match containing its locally cached ETAG value.
 117          *
 118          * To get more information, you will have to look at HTTP/1.1 protocol which
 119          * is properly described in RFC 2616 : http://tools.ietf.org/html/rfc2616
 120          */
 121         private $mETag = false;
 122
 123         /** @var array */
 124         protected $mCategoryLinks = [];
 125
 126         /** @var array */
 127         protected $mCategories = [];
 128
 129         /** @var array */
 130         protected $mIndicators = [];
 131
 132         /** @var array Array of Interwiki Prefixed (non DB key) Titles (e.g. 'fr:Test page') */
 133         private $mLanguageLinks = [];
 134
 135         /**
 136          * Used for JavaScript (predates ResourceLoader)
 137          * @todo We should split JS / CSS.
 138          * mScripts content is inserted as is in "<head>" by Skin. This might
 139          * contain either a link to a stylesheet or inline CSS.
 140          */
 141         private $mScripts = '';
 142
 143         /** @var string Inline CSS styles. Use addInlineStyle() sparingly */
 144         protected $mInlineStyles = '';
 145
 146         /**
 147          * @var string Used by skin template.
 148          * Example: $tpl->set( 'displaytitle', $out->mPageLinkTitle );
 149          */
 150         public $mPageLinkTitle = '';
 151
 152         /** @var array Array of elements in "<head>". Parser might add its own headers! */
 153         protected $mHeadItems = [];
 154
 155         /** @var array */
 156         protected $mModules = [];
 157
 158         /** @var array */
 159         protected $mModuleScripts = [];
 160
 161         /** @var array */
 162         protected $mModuleStyles = [];
 163
 164         /** @var ResourceLoader */
 165         protected $mResourceLoader;
 166
 167         /** @var array */
 168         protected $mJsConfigVars = [];
 169
 170         /** @var array */
 171         protected $mTemplateIds = [];
 172
 173         /** @var array */
 174         protected $mImageTimeKeys = [];
 175
 176         /** @var string */
 177         public $mRedirectCode = '';
 178
 179         protected $mFeedLinksAppendQuery = null;
 180
 181         /** @var array
 182          * What level of 'untrustworthiness' is allowed in CSS/JS modules loaded on this page?
 183          * @see ResourceLoaderModule::$origin
 184          * ResourceLoaderModule::ORIGIN_ALL is assumed unless overridden;
 185          */
 186         protected $mAllowedModules = [
 187                 ResourceLoaderModule::TYPE_COMBINED => ResourceLoaderModule::ORIGIN_ALL,
 188         ];
 189
 190         /** @var bool Whether output is disabled.  If this is true, the 'output' method will do nothing. */
 191         protected $mDoNothing = false;
 192
 193         // Parser related.
 194
 195         /** @var int */
 196         protected $mContainsNewMagic = 0;
 197
 198         /**
 199          * lazy initialised, use parserOptions()
 200          * @var ParserOptions
 201          */
 202         protected $mParserOptions = null;
 203
 204         /**
 205          * Handles the Atom / RSS links.
 206          * We probably only support Atom in 2011.
 207          * @see $wgAdvertisedFeedTypes
 208          */
 209         private $mFeedLinks = [];
 210
 211         // Gwicke work on squid caching? Roughly from 2003.
 212         protected $mEnableClientCache = true;
 213
 214         /** @var bool Flag if output should only contain the body of the article. */
 215         private $mArticleBodyOnly = false;
 216
 217         /** @var bool */
 218         protected $mNewSectionLink = false;
 219
 220         /** @var bool */
 221         protected $mHideNewSectionLink = false;
 222
 223         /**
 224          * @var bool Comes from the parser. This was probably made to load CSS/JS
 225          * only if we had "<gallery>". Used directly in CategoryPage.php.
 226          * Looks like ResourceLoader can replace this.
 227          */
 228         public $mNoGallery = false;
 229
 230         /** @var string */
 231         private $mPageTitleActionText = '';
 232
 233         /** @var int Cache stuff. Looks like mEnableClientCache */
 234         protected $mCdnMaxage = 0;
 235         /** @var int Upper limit on mCdnMaxage */
 236         protected $mCdnMaxageLimit = INF;
 237
 238         /**
 239          * @var bool Controls if anti-clickjacking / frame-breaking headers will
 240          * be sent. This should be done for pages where edit actions are possible.
 241          * Setters: $this->preventClickjacking() and $this->allowClickjacking().
 242          */
 243         protected $mPreventClickjacking = true;
 244
 245         /** @var int To include the variable {{REVISIONID}} */
 246         private $mRevisionId = null;
 247
 248         /** @var string */
 249         private $mRevisionTimestamp = null;
 250
 251         /** @var array */
 252         protected $mFileVersion = null;
 253
 254         /**
 255          * @var array An array of stylesheet filenames (relative from skins path),
 256          * with options for CSS media, IE conditions, and RTL/LTR direction.
 257          * For internal use; add settings in the skin via $this->addStyle()
 258          *
 259          * Style again! This seems like a code duplication since we already have
 260          * mStyles. This is what makes Open Source amazing.
 261          */
 262         protected $styles = [];
 263
 264         /**
 265          * Whether jQuery is already handled.
 266          */
 267         protected $mJQueryDone = false;
 268
 269         private $mIndexPolicy = 'index';
 270         private $mFollowPolicy = 'follow';
 271         private $mVaryHeader = [
 272                 'Accept-Encoding' => [ 'match=gzip' ],
 273         ];
 274
 275         /**
 276          * If the current page was reached through a redirect, $mRedirectedFrom contains the Title
 277          * of the redirect.
 278          *
 279          * @var Title
 280          */
 281         private $mRedirectedFrom = null;
 282
 283         /**
 284          * Additional key => value data
 285          */
 286         private $mProperties = [];
 287
 288         /**
 289          * @var string|null ResourceLoader target for load.php links. If null, will be omitted
 290          */
 291         private $mTarget = null;
 292
 293         /**
 294          * @var bool Whether parser output should contain table of contents
 295          */
 296         private $mEnableTOC = true;
 297
 298         /**
 299          * @var bool Whether parser output should contain section edit links
 300          */
 301         private $mEnableSectionEditLinks = true;
 302
 303         /**
 304          * @var string|null The URL to send in a <link> element with rel=copyright
 305          */
 306         private $copyrightUrl;
 307
 308         /**
 309          * Constructor for OutputPage. This should not be called directly.
 310          * Instead a new RequestContext should be created and it will implicitly create
 311          * a OutputPage tied to that context.
 312          * @param IContextSource|null $context
 313          */
 314         function __construct( IContextSource $context = null ) {
 315                 if ( $context === null ) {
 316                         # Extensions should use `new RequestContext` instead of `new OutputPage` now.
 317                         wfDeprecated( __METHOD__, '1.18' );
 318                 } else {
 319                         $this->setContext( $context );
 320                 }
 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() == $position )
 540                                 && ( !$this->mTarget || in_array( $this->mTarget, $module->getTargets() ) )
 541                         ) {
 542                                 $filteredModules[] = $val;
 543                         }
 544                 }
 545                 return $filteredModules;
 546         }
 547
 548         /**
 549          * Get the list of modules to include on this page
 550          *
 551          * @param bool $filter Whether to filter out insufficiently trustworthy modules
 552          * @param string|null $position If not null, only return modules with this position
 553          * @param string $param
 554          * @return array Array of module names
 555          */
 556         public function getModules( $filter = false, $position = null, $param = 'mModules' ) {
 557                 $modules = array_values( array_unique( $this->$param ) );
 558                 return $filter
 559                         ? $this->filterModules( $modules, $position )
 560                         : $modules;
 561         }
 562
 563         /**
 564          * Add one or more modules recognized by ResourceLoader. Modules added
 565          * through this function will be loaded by ResourceLoader when the
 566          * page loads.
 567          *
 568          * @param string|array $modules Module name (string) or array of module names
 569          */
 570         public function addModules( $modules ) {
 571                 $this->mModules = array_merge( $this->mModules, (array)$modules );
 572         }
 573
 574         /**
 575          * Get the list of module JS to include on this page
 576          *
 577          * @param bool $filter
 578          * @param string|null $position
 579          *
 580          * @return array Array of module names
 581          */
 582         public function getModuleScripts( $filter = false, $position = null ) {
 583                 return $this->getModules( $filter, $position, 'mModuleScripts' );
 584         }
 585
 586         /**
 587          * Add only JS of one or more modules recognized by ResourceLoader. Module
 588          * scripts added through this function will be loaded by ResourceLoader when
 589          * the page loads.
 590          *
 591          * @param string|array $modules Module name (string) or array of module names
 592          */
 593         public function addModuleScripts( $modules ) {
 594                 $this->mModuleScripts = array_merge( $this->mModuleScripts, (array)$modules );
 595         }
 596
 597         /**
 598          * Get the list of module CSS to include on this page
 599          *
 600          * @param bool $filter
 601          * @param string|null $position
 602          *
 603          * @return array Array of module names
 604          */
 605         public function getModuleStyles( $filter = false, $position = null ) {
 606                 return $this->getModules( $filter, $position, 'mModuleStyles' );
 607         }
 608
 609         /**
 610          * Add only CSS of one or more modules recognized by ResourceLoader.
 611          *
 612          * Module styles added through this function will be added using standard link CSS
 613          * tags, rather than as a combined Javascript and CSS package. Thus, they will
 614          * load when JavaScript is disabled (unless CSS also happens to be disabled).
 615          *
 616          * @param string|array $modules Module name (string) or array of module names
 617          */
 618         public function addModuleStyles( $modules ) {
 619                 $this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
 620         }
 621
 622         /**
 623          * Get the list of module messages to include on this page
 624          *
 625          * @deprecated since 1.26 Obsolete
 626          * @param bool $filter
 627          * @param string|null $position
 628          * @return array Array of module names
 629          */
 630         public function getModuleMessages( $filter = false, $position = null ) {
 631                 wfDeprecated( __METHOD__, '1.26' );
 632                 return [];
 633         }
 634
 635         /**
 636          * Load messages of one or more ResourceLoader modules.
 637          *
 638          * @deprecated since 1.26 Use addModules() instead
 639          * @param string|array $modules Module name (string) or array of module names
 640          */
 641         public function addModuleMessages( $modules ) {
 642                 wfDeprecated( __METHOD__, '1.26' );
 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 an header 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          * Check if the header item $name is already set
 688          *
 689          * @param string $name Item name
 690          * @return bool
 691          */
 692         public function hasHeadItem( $name ) {
 693                 return isset( $this->mHeadItems[$name] );
 694         }
 695
 696         /**
 697          * Set the value of the ETag HTTP header, only used if $wgUseETag is true
 698          *
 699          * @param string $tag Value of "ETag" header
 700          */
 701         function setETag( $tag ) {
 702                 $this->mETag = $tag;
 703         }
 704
 705         /**
 706          * Set whether the output should only contain the body of the article,
 707          * without any skin, sidebar, etc.
 708          * Used e.g. when calling with "action=render".
 709          *
 710          * @param bool $only Whether to output only the body of the article
 711          */
 712         public function setArticleBodyOnly( $only ) {
 713                 $this->mArticleBodyOnly = $only;
 714         }
 715
 716         /**
 717          * Return whether the output will contain only the body of the article
 718          *
 719          * @return bool
 720          */
 721         public function getArticleBodyOnly() {
 722                 return $this->mArticleBodyOnly;
 723         }
 724
 725         /**
 726          * Set an additional output property
 727          * @since 1.21
 728          *
 729          * @param string $name
 730          * @param mixed $value
 731          */
 732         public function setProperty( $name, $value ) {
 733                 $this->mProperties[$name] = $value;
 734         }
 735
 736         /**
 737          * Get an additional output property
 738          * @since 1.21
 739          *
 740          * @param string $name
 741          * @return mixed Property value or null if not found
 742          */
 743         public function getProperty( $name ) {
 744                 if ( isset( $this->mProperties[$name] ) ) {
 745                         return $this->mProperties[$name];
 746                 } else {
 747                         return null;
 748                 }
 749         }
 750
 751         /**
 752          * checkLastModified tells the client to use the client-cached page if
 753          * possible. If successful, the OutputPage is disabled so that
 754          * any future call to OutputPage->output() have no effect.
 755          *
 756          * Side effect: sets mLastModified for Last-Modified header
 757          *
 758          * @param string $timestamp
 759          *
 760          * @return bool True if cache-ok headers was sent.
 761          */
 762         public function checkLastModified( $timestamp ) {
 763                 if ( !$timestamp || $timestamp == '19700101000000' ) {
 764                         wfDebug( __METHOD__ . ": CACHE DISABLED, NO TIMESTAMP\n" );
 765                         return false;
 766                 }
 767                 $config = $this->getConfig();
 768                 if ( !$config->get( 'CachePages' ) ) {
 769                         wfDebug( __METHOD__ . ": CACHE DISABLED\n" );
 770                         return false;
 771                 }
 772
 773                 $timestamp = wfTimestamp( TS_MW, $timestamp );
 774                 $modifiedTimes = [
 775                         'page' => $timestamp,
 776                         'user' => $this->getUser()->getTouched(),
 777                         'epoch' => $config->get( 'CacheEpoch' )
 778                 ];
 779                 if ( $config->get( 'UseSquid' ) ) {
 780                         // bug 44570: the core page itself may not change, but resources might
 781                         $modifiedTimes['sepoch'] = wfTimestamp( TS_MW, time() - $config->get( 'SquidMaxage' ) );
 782                 }
 783                 Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes ] );
 784
 785                 $maxModified = max( $modifiedTimes );
 786                 $this->mLastModified = wfTimestamp( TS_RFC2822, $maxModified );
 787
 788                 $clientHeader = $this->getRequest()->getHeader( 'If-Modified-Since' );
 789                 if ( $clientHeader === false ) {
 790                         wfDebug( __METHOD__ . ": client did not send If-Modified-Since header", 'private' );
 791                         return false;
 792                 }
 793
 794                 # IE sends sizes after the date like this:
 795                 # Wed, 20 Aug 2003 06:51:19 GMT; length=5202
 796                 # this breaks strtotime().
 797                 $clientHeader = preg_replace( '/;.*$/', '', $clientHeader );
 798
 799                 MediaWiki\suppressWarnings(); // E_STRICT system time bitching
 800                 $clientHeaderTime = strtotime( $clientHeader );
 801                 MediaWiki\restoreWarnings();
 802                 if ( !$clientHeaderTime ) {
 803                         wfDebug( __METHOD__
 804                                 . ": unable to parse the client's If-Modified-Since header: $clientHeader\n" );
 805                         return false;
 806                 }
 807                 $clientHeaderTime = wfTimestamp( TS_MW, $clientHeaderTime );
 808
 809                 # Make debug info
 810                 $info = '';
 811                 foreach ( $modifiedTimes as $name => $value ) {
 812                         if ( $info !== '' ) {
 813                                 $info .= ', ';
 814                         }
 815                         $info .= "$name=" . wfTimestamp( TS_ISO_8601, $value );
 816                 }
 817
 818                 wfDebug( __METHOD__ . ": client sent If-Modified-Since: " .
 819                         wfTimestamp( TS_ISO_8601, $clientHeaderTime ), 'private' );
 820                 wfDebug( __METHOD__ . ": effective Last-Modified: " .
 821                         wfTimestamp( TS_ISO_8601, $maxModified ), 'private' );
 822                 if ( $clientHeaderTime < $maxModified ) {
 823                         wfDebug( __METHOD__ . ": STALE, $info", 'private' );
 824                         return false;
 825                 }
 826
 827                 # Not modified
 828                 # Give a 304 Not Modified response code and disable body output
 829                 wfDebug( __METHOD__ . ": NOT MODIFIED, $info", 'private' );
 830                 ini_set( 'zlib.output_compression', 0 );
 831                 $this->getRequest()->response()->statusHeader( 304 );
 832                 $this->sendCacheControl();
 833                 $this->disable();
 834
 835                 // Don't output a compressed blob when using ob_gzhandler;
 836                 // it's technically against HTTP spec and seems to confuse
 837                 // Firefox when the response gets split over two packets.
 838                 wfClearOutputBuffers();
 839
 840                 return true;
 841         }
 842
 843         /**
 844          * Override the last modified timestamp
 845          *
 846          * @param string $timestamp New timestamp, in a format readable by
 847          *        wfTimestamp()
 848          */
 849         public function setLastModified( $timestamp ) {
 850                 $this->mLastModified = wfTimestamp( TS_RFC2822, $timestamp );
 851         }
 852
 853         /**
 854          * Set the robot policy for the page: <http://www.robotstxt.org/meta.html>
 855          *
 856          * @param string $policy The literal string to output as the contents of
 857          *   the meta tag.  Will be parsed according to the spec and output in
 858          *   standardized form.
 859          * @return null
 860          */
 861         public function setRobotPolicy( $policy ) {
 862                 $policy = Article::formatRobotPolicy( $policy );
 863
 864                 if ( isset( $policy['index'] ) ) {
 865                         $this->setIndexPolicy( $policy['index'] );
 866                 }
 867                 if ( isset( $policy['follow'] ) ) {
 868                         $this->setFollowPolicy( $policy['follow'] );
 869                 }
 870         }
 871
 872         /**
 873          * Set the index policy for the page, but leave the follow policy un-
 874          * touched.
 875          *
 876          * @param string $policy Either 'index' or 'noindex'.
 877          * @return null
 878          */
 879         public function setIndexPolicy( $policy ) {
 880                 $policy = trim( $policy );
 881                 if ( in_array( $policy, [ 'index', 'noindex' ] ) ) {
 882                         $this->mIndexPolicy = $policy;
 883                 }
 884         }
 885
 886         /**
 887          * Set the follow policy for the page, but leave the index policy un-
 888          * touched.
 889          *
 890          * @param string $policy Either 'follow' or 'nofollow'.
 891          * @return null
 892          */
 893         public function setFollowPolicy( $policy ) {
 894                 $policy = trim( $policy );
 895                 if ( in_array( $policy, [ 'follow', 'nofollow' ] ) ) {
 896                         $this->mFollowPolicy = $policy;
 897                 }
 898         }
 899
 900         /**
 901          * Set the new value of the "action text", this will be added to the
 902          * "HTML title", separated from it with " - ".
 903          *
 904          * @param string $text New value of the "action text"
 905          */
 906         public function setPageTitleActionText( $text ) {
 907                 $this->mPageTitleActionText = $text;
 908         }
 909
 910         /**
 911          * Get the value of the "action text"
 912          *
 913          * @return string
 914          */
 915         public function getPageTitleActionText() {
 916                 return $this->mPageTitleActionText;
 917         }
 918
 919         /**
 920          * "HTML title" means the contents of "<title>".
 921          * It is stored as plain, unescaped text and will be run through htmlspecialchars in the skin file.
 922          *
 923          * @param string|Message $name
 924          */
 925         public function setHTMLTitle( $name ) {
 926                 if ( $name instanceof Message ) {
 927                         $this->mHTMLtitle = $name->setContext( $this->getContext() )->text();
 928                 } else {
 929                         $this->mHTMLtitle = $name;
 930                 }
 931         }
 932
 933         /**
 934          * Return the "HTML title", i.e. the content of the "<title>" tag.
 935          *
 936          * @return string
 937          */
 938         public function getHTMLTitle() {
 939                 return $this->mHTMLtitle;
 940         }
 941
 942         /**
 943          * Set $mRedirectedFrom, the Title of the page which redirected us to the current page.
 944          *
 945          * @param Title $t
 946          */
 947         public function setRedirectedFrom( $t ) {
 948                 $this->mRedirectedFrom = $t;
 949         }
 950
 951         /**
 952          * "Page title" means the contents of \<h1\>. It is stored as a valid HTML
 953          * fragment. This function allows good tags like \<sup\> in the \<h1\> tag,
 954          * but not bad tags like \<script\>. This function automatically sets
 955          * \<title\> to the same content as \<h1\> but with all tags removed. Bad
 956          * tags that were escaped in \<h1\> will still be escaped in \<title\>, and
 957          * good tags like \<i\> will be dropped entirely.
 958          *
 959          * @param string|Message $name
 960          */
 961         public function setPageTitle( $name ) {
 962                 if ( $name instanceof Message ) {
 963                         $name = $name->setContext( $this->getContext() )->text();
 964                 }
 965
 966                 # change "<script>foo&bar</script>" to "&lt;script&gt;foo&amp;bar&lt;/script&gt;"
 967                 # but leave "<i>foobar</i>" alone
 968                 $nameWithTags = Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $name ) );
 969                 $this->mPagetitle = $nameWithTags;
 970
 971                 # change "<i>foo&amp;bar</i>" to "foo&bar"
 972                 $this->setHTMLTitle(
 973                         $this->msg( 'pagetitle' )->rawParams( Sanitizer::stripAllTags( $nameWithTags ) )
 974                                 ->inContentLanguage()
 975                 );
 976         }
 977
 978         /**
 979          * Return the "page title", i.e. the content of the \<h1\> tag.
 980          *
 981          * @return string
 982          */
 983         public function getPageTitle() {
 984                 return $this->mPagetitle;
 985         }
 986
 987         /**
 988          * Set the Title object to use
 989          *
 990          * @param Title $t
 991          */
 992         public function setTitle( Title $t ) {
 993                 $this->getContext()->setTitle( $t );
 994         }
 995
 996         /**
 997          * Replace the subtitle with $str
 998          *
 999          * @param string|Message $str New value of the subtitle. String should be safe HTML.
1000          */
1001         public function setSubtitle( $str ) {
1002                 $this->clearSubtitle();
1003                 $this->addSubtitle( $str );
1004         }
1005
1006         /**
1007          * Add $str to the subtitle
1008          *
1009          * @param string|Message $str String or Message to add to the subtitle. String should be safe HTML.
1010          */
1011         public function addSubtitle( $str ) {
1012                 if ( $str instanceof Message ) {
1013                         $this->mSubtitle[] = $str->setContext( $this->getContext() )->parse();
1014                 } else {
1015                         $this->mSubtitle[] = $str;
1016                 }
1017         }
1018
1019         /**
1020          * Build message object for a subtitle containing a backlink to a page
1021          *
1022          * @param Title $title Title to link to
1023          * @param array $query Array of additional parameters to include in the link
1024          * @return Message
1025          * @since 1.25
1026          */
1027         public static function buildBacklinkSubtitle( Title $title, $query = [] ) {
1028                 if ( $title->isRedirect() ) {
1029                         $query['redirect'] = 'no';
1030                 }
1031                 return wfMessage( 'backlinksubtitle' )
1032                         ->rawParams( Linker::link( $title, null, [], $query ) );
1033         }
1034
1035         /**
1036          * Add a subtitle containing a backlink to a page
1037          *
1038          * @param Title $title Title to link to
1039          * @param array $query Array of additional parameters to include in the link
1040          */
1041         public function addBacklinkSubtitle( Title $title, $query = [] ) {
1042                 $this->addSubtitle( self::buildBacklinkSubtitle( $title, $query ) );
1043         }
1044
1045         /**
1046          * Clear the subtitles
1047          */
1048         public function clearSubtitle() {
1049                 $this->mSubtitle = [];
1050         }
1051
1052         /**
1053          * Get the subtitle
1054          *
1055          * @return string
1056          */
1057         public function getSubtitle() {
1058                 return implode( "<br />\n\t\t\t\t", $this->mSubtitle );
1059         }
1060
1061         /**
1062          * Set the page as printable, i.e. it'll be displayed with all
1063          * print styles included
1064          */
1065         public function setPrintable() {
1066                 $this->mPrintable = true;
1067         }
1068
1069         /**
1070          * Return whether the page is "printable"
1071          *
1072          * @return bool
1073          */
1074         public function isPrintable() {
1075                 return $this->mPrintable;
1076         }
1077
1078         /**
1079          * Disable output completely, i.e. calling output() will have no effect
1080          */
1081         public function disable() {
1082                 $this->mDoNothing = true;
1083         }
1084
1085         /**
1086          * Return whether the output will be completely disabled
1087          *
1088          * @return bool
1089          */
1090         public function isDisabled() {
1091                 return $this->mDoNothing;
1092         }
1093
1094         /**
1095          * Show an "add new section" link?
1096          *
1097          * @return bool
1098          */
1099         public function showNewSectionLink() {
1100                 return $this->mNewSectionLink;
1101         }
1102
1103         /**
1104          * Forcibly hide the new section link?
1105          *
1106          * @return bool
1107          */
1108         public function forceHideNewSectionLink() {
1109                 return $this->mHideNewSectionLink;
1110         }
1111
1112         /**
1113          * Add or remove feed links in the page header
1114          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1115          * for the new version
1116          * @see addFeedLink()
1117          *
1118          * @param bool $show True: add default feeds, false: remove all feeds
1119          */
1120         public function setSyndicated( $show = true ) {
1121                 if ( $show ) {
1122                         $this->setFeedAppendQuery( false );
1123                 } else {
1124                         $this->mFeedLinks = [];
1125                 }
1126         }
1127
1128         /**
1129          * Add default feeds to the page header
1130          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1131          * for the new version
1132          * @see addFeedLink()
1133          *
1134          * @param string $val Query to append to feed links or false to output
1135          *        default links
1136          */
1137         public function setFeedAppendQuery( $val ) {
1138                 $this->mFeedLinks = [];
1139
1140                 foreach ( $this->getConfig()->get( 'AdvertisedFeedTypes' ) as $type ) {
1141                         $query = "feed=$type";
1142                         if ( is_string( $val ) ) {
1143                                 $query .= '&' . $val;
1144                         }
1145                         $this->mFeedLinks[$type] = $this->getTitle()->getLocalURL( $query );
1146                 }
1147         }
1148
1149         /**
1150          * Add a feed link to the page header
1151          *
1152          * @param string $format Feed type, should be a key of $wgFeedClasses
1153          * @param string $href URL
1154          */
1155         public function addFeedLink( $format, $href ) {
1156                 if ( in_array( $format, $this->getConfig()->get( 'AdvertisedFeedTypes' ) ) ) {
1157                         $this->mFeedLinks[$format] = $href;
1158                 }
1159         }
1160
1161         /**
1162          * Should we output feed links for this page?
1163          * @return bool
1164          */
1165         public function isSyndicated() {
1166                 return count( $this->mFeedLinks ) > 0;
1167         }
1168
1169         /**
1170          * Return URLs for each supported syndication format for this page.
1171          * @return array Associating format keys with URLs
1172          */
1173         public function getSyndicationLinks() {
1174                 return $this->mFeedLinks;
1175         }
1176
1177         /**
1178          * Will currently always return null
1179          *
1180          * @return null
1181          */
1182         public function getFeedAppendQuery() {
1183                 return $this->mFeedLinksAppendQuery;
1184         }
1185
1186         /**
1187          * Set whether the displayed content is related to the source of the
1188          * corresponding article on the wiki
1189          * Setting true will cause the change "article related" toggle to true
1190          *
1191          * @param bool $v
1192          */
1193         public function setArticleFlag( $v ) {
1194                 $this->mIsarticle = $v;
1195                 if ( $v ) {
1196                         $this->mIsArticleRelated = $v;
1197                 }
1198         }
1199
1200         /**
1201          * Return whether the content displayed page is related to the source of
1202          * the corresponding article on the wiki
1203          *
1204          * @return bool
1205          */
1206         public function isArticle() {
1207                 return $this->mIsarticle;
1208         }
1209
1210         /**
1211          * Set whether this page is related an article on the wiki
1212          * Setting false will cause the change of "article flag" toggle to false
1213          *
1214          * @param bool $v
1215          */
1216         public function setArticleRelated( $v ) {
1217                 $this->mIsArticleRelated = $v;
1218                 if ( !$v ) {
1219                         $this->mIsarticle = false;
1220                 }
1221         }
1222
1223         /**
1224          * Return whether this page is related an article on the wiki
1225          *
1226          * @return bool
1227          */
1228         public function isArticleRelated() {
1229                 return $this->mIsArticleRelated;
1230         }
1231
1232         /**
1233          * Add new language links
1234          *
1235          * @param array $newLinkArray Associative array mapping language code to the page
1236          *                      name
1237          */
1238         public function addLanguageLinks( array $newLinkArray ) {
1239                 $this->mLanguageLinks += $newLinkArray;
1240         }
1241
1242         /**
1243          * Reset the language links and add new language links
1244          *
1245          * @param array $newLinkArray Associative array mapping language code to the page
1246          *                      name
1247          */
1248         public function setLanguageLinks( array $newLinkArray ) {
1249                 $this->mLanguageLinks = $newLinkArray;
1250         }
1251
1252         /**
1253          * Get the list of language links
1254          *
1255          * @return array Array of Interwiki Prefixed (non DB key) Titles (e.g. 'fr:Test page')
1256          */
1257         public function getLanguageLinks() {
1258                 return $this->mLanguageLinks;
1259         }
1260
1261         /**
1262          * Add an array of categories, with names in the keys
1263          *
1264          * @param array $categories Mapping category name => sort key
1265          */
1266         public function addCategoryLinks( array $categories ) {
1267                 global $wgContLang;
1268
1269                 if ( !is_array( $categories ) || count( $categories ) == 0 ) {
1270                         return;
1271                 }
1272
1273                 # Add the links to a LinkBatch
1274                 $arr = [ NS_CATEGORY => $categories ];
1275                 $lb = new LinkBatch;
1276                 $lb->setArray( $arr );
1277
1278                 # Fetch existence plus the hiddencat property
1279                 $dbr = wfGetDB( DB_SLAVE );
1280                 $fields = [ 'page_id', 'page_namespace', 'page_title', 'page_len',
1281                         'page_is_redirect', 'page_latest', 'pp_value' ];
1282
1283                 if ( $this->getConfig()->get( 'ContentHandlerUseDB' ) ) {
1284                         $fields[] = 'page_content_model';
1285                 }
1286                 if ( $this->getConfig()->get( 'PageLanguageUseDB' ) ) {
1287                         $fields[] = 'page_lang';
1288                 }
1289
1290                 $res = $dbr->select( [ 'page', 'page_props' ],
1291                         $fields,
1292                         $lb->constructSet( 'page', $dbr ),
1293                         __METHOD__,
1294                         [],
1295                         [ 'page_props' => [ 'LEFT JOIN', [
1296                                 'pp_propname' => 'hiddencat',
1297                                 'pp_page = page_id'
1298                         ] ] ]
1299                 );
1300
1301                 # Add the results to the link cache
1302                 $lb->addResultToCache( LinkCache::singleton(), $res );
1303
1304                 # Set all the values to 'normal'.
1305                 $categories = array_fill_keys( array_keys( $categories ), 'normal' );
1306
1307                 # Mark hidden categories
1308                 foreach ( $res as $row ) {
1309                         if ( isset( $row->pp_value ) ) {
1310                                 $categories[$row->page_title] = 'hidden';
1311                         }
1312                 }
1313
1314                 # Add the remaining categories to the skin
1315                 if ( Hooks::run(
1316                         'OutputPageMakeCategoryLinks',
1317                         [ &$this, $categories, &$this->mCategoryLinks ] )
1318                 ) {
1319                         foreach ( $categories as $category => $type ) {
1320                                 // array keys will cast numeric category names to ints, so cast back to string
1321                                 $category = (string)$category;
1322                                 $origcategory = $category;
1323                                 $title = Title::makeTitleSafe( NS_CATEGORY, $category );
1324                                 if ( !$title ) {
1325                                         continue;
1326                                 }
1327                                 $wgContLang->findVariantLink( $category, $title, true );
1328                                 if ( $category != $origcategory && array_key_exists( $category, $categories ) ) {
1329                                         continue;
1330                                 }
1331                                 $text = $wgContLang->convertHtml( $title->getText() );
1332                                 $this->mCategories[] = $title->getText();
1333                                 $this->mCategoryLinks[$type][] = Linker::link( $title, $text );
1334                         }
1335                 }
1336         }
1337
1338         /**
1339          * Reset the category links (but not the category list) and add $categories
1340          *
1341          * @param array $categories Mapping category name => sort key
1342          */
1343         public function setCategoryLinks( array $categories ) {
1344                 $this->mCategoryLinks = [];
1345                 $this->addCategoryLinks( $categories );
1346         }
1347
1348         /**
1349          * Get the list of category links, in a 2-D array with the following format:
1350          * $arr[$type][] = $link, where $type is either "normal" or "hidden" (for
1351          * hidden categories) and $link a HTML fragment with a link to the category
1352          * page
1353          *
1354          * @return array
1355          */
1356         public function getCategoryLinks() {
1357                 return $this->mCategoryLinks;
1358         }
1359
1360         /**
1361          * Get the list of category names this page belongs to
1362          *
1363          * @return array Array of strings
1364          */
1365         public function getCategories() {
1366                 return $this->mCategories;
1367         }
1368
1369         /**
1370          * Add an array of indicators, with their identifiers as array
1371          * keys and HTML contents as values.
1372          *
1373          * In case of duplicate keys, existing values are overwritten.
1374          *
1375          * @param array $indicators
1376          * @since 1.25
1377          */
1378         public function setIndicators( array $indicators ) {
1379                 $this->mIndicators = $indicators + $this->mIndicators;
1380                 // Keep ordered by key
1381                 ksort( $this->mIndicators );
1382         }
1383
1384         /**
1385          * Get the indicators associated with this page.
1386          *
1387          * The array will be internally ordered by item keys.
1388          *
1389          * @return array Keys: identifiers, values: HTML contents
1390          * @since 1.25
1391          */
1392         public function getIndicators() {
1393                 return $this->mIndicators;
1394         }
1395
1396         /**
1397          * Adds help link with an icon via page indicators.
1398          * Link target can be overridden by a local message containing a wikilink:
1399          * the message key is: lowercase action or special page name + '-helppage'.
1400          * @param string $to Target MediaWiki.org page title or encoded URL.
1401          * @param bool $overrideBaseUrl Whether $url is a full URL, to avoid MW.o.
1402          * @since 1.25
1403          */
1404         public function addHelpLink( $to, $overrideBaseUrl = false ) {
1405                 $this->addModuleStyles( 'mediawiki.helplink' );
1406                 $text = $this->msg( 'helppage-top-gethelp' )->escaped();
1407
1408                 if ( $overrideBaseUrl ) {
1409                         $helpUrl = $to;
1410                 } else {
1411                         $toUrlencoded = wfUrlencode( str_replace( ' ', '_', $to ) );
1412                         $helpUrl = "//www.mediawiki.org/wiki/Special:MyLanguage/$toUrlencoded";
1413                 }
1414
1415                 $link = Html::rawElement(
1416                         'a',
1417                         [
1418                                 'href' => $helpUrl,
1419                                 'target' => '_blank',
1420                                 'class' => 'mw-helplink',
1421                         ],
1422                         $text
1423                 );
1424
1425                 $this->setIndicators( [ 'mw-helplink' => $link ] );
1426         }
1427
1428         /**
1429          * Do not allow scripts which can be modified by wiki users to load on this page;
1430          * only allow scripts bundled with, or generated by, the software.
1431          * Site-wide styles are controlled by a config setting, since they can be
1432          * used to create a custom skin/theme, but not user-specific ones.
1433          *
1434          * @todo this should be given a more accurate name
1435          */
1436         public function disallowUserJs() {
1437                 $this->reduceAllowedModules(
1438                         ResourceLoaderModule::TYPE_SCRIPTS,
1439                         ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
1440                 );
1441
1442                 // Site-wide styles are controlled by a config setting, see bug 71621
1443                 // for background on why. User styles are never allowed.
1444                 if ( $this->getConfig()->get( 'AllowSiteCSSOnRestrictedPages' ) ) {
1445                         $styleOrigin = ResourceLoaderModule::ORIGIN_USER_SITEWIDE;
1446                 } else {
1447                         $styleOrigin = ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL;
1448                 }
1449                 $this->reduceAllowedModules(
1450                         ResourceLoaderModule::TYPE_STYLES,
1451                         $styleOrigin
1452                 );
1453         }
1454
1455         /**
1456          * Show what level of JavaScript / CSS untrustworthiness is allowed on this page
1457          * @see ResourceLoaderModule::$origin
1458          * @param string $type ResourceLoaderModule TYPE_ constant
1459          * @return int ResourceLoaderModule ORIGIN_ class constant
1460          */
1461         public function getAllowedModules( $type ) {
1462                 if ( $type == ResourceLoaderModule::TYPE_COMBINED ) {
1463                         return min( array_values( $this->mAllowedModules ) );
1464                 } else {
1465                         return isset( $this->mAllowedModules[$type] )
1466                                 ? $this->mAllowedModules[$type]
1467                                 : ResourceLoaderModule::ORIGIN_ALL;
1468                 }
1469         }
1470
1471         /**
1472          * Limit the highest level of CSS/JS untrustworthiness allowed.
1473          *
1474          * If passed the same or a higher level than the current level of untrustworthiness set, the
1475          * level will remain unchanged.
1476          *
1477          * @param string $type
1478          * @param int $level ResourceLoaderModule class constant
1479          */
1480         public function reduceAllowedModules( $type, $level ) {
1481                 $this->mAllowedModules[$type] = min( $this->getAllowedModules( $type ), $level );
1482         }
1483
1484         /**
1485          * Prepend $text to the body HTML
1486          *
1487          * @param string $text HTML
1488          */
1489         public function prependHTML( $text ) {
1490                 $this->mBodytext = $text . $this->mBodytext;
1491         }
1492
1493         /**
1494          * Append $text to the body HTML
1495          *
1496          * @param string $text HTML
1497          */
1498         public function addHTML( $text ) {
1499                 $this->mBodytext .= $text;
1500         }
1501
1502         /**
1503          * Shortcut for adding an Html::element via addHTML.
1504          *
1505          * @since 1.19
1506          *
1507          * @param string $element
1508          * @param array $attribs
1509          * @param string $contents
1510          */
1511         public function addElement( $element, array $attribs = [], $contents = '' ) {
1512                 $this->addHTML( Html::element( $element, $attribs, $contents ) );
1513         }
1514
1515         /**
1516          * Clear the body HTML
1517          */
1518         public function clearHTML() {
1519                 $this->mBodytext = '';
1520         }
1521
1522         /**
1523          * Get the body HTML
1524          *
1525          * @return string HTML
1526          */
1527         public function getHTML() {
1528                 return $this->mBodytext;
1529         }
1530
1531         /**
1532          * Get/set the ParserOptions object to use for wikitext parsing
1533          *
1534          * @param ParserOptions|null $options Either the ParserOption to use or null to only get the
1535          *   current ParserOption object
1536          * @return ParserOptions
1537          */
1538         public function parserOptions( $options = null ) {
1539                 if ( $options !== null && !empty( $options->isBogus ) ) {
1540                         // Someone is trying to set a bogus pre-$wgUser PO. Check if it has
1541                         // been changed somehow, and keep it if so.
1542                         $anonPO = ParserOptions::newFromAnon();
1543                         $anonPO->setEditSection( false );
1544                         if ( !$options->matches( $anonPO ) ) {
1545                                 wfLogWarning( __METHOD__ . ': Setting a changed bogus ParserOptions: ' . wfGetAllCallers( 5 ) );
1546                                 $options->isBogus = false;
1547                         }
1548                 }
1549
1550                 if ( !$this->mParserOptions ) {
1551                         if ( !$this->getContext()->getUser()->isSafeToLoad() ) {
1552                                 // $wgUser isn't unstubbable yet, so don't try to get a
1553                                 // ParserOptions for it. And don't cache this ParserOptions
1554                                 // either.
1555                                 $po = ParserOptions::newFromAnon();
1556                                 $po->setEditSection( false );
1557                                 $po->isBogus = true;
1558                                 if ( $options !== null ) {
1559                                         $this->mParserOptions = empty( $options->isBogus ) ? $options : null;
1560                                 }
1561                                 return $po;
1562                         }
1563
1564                         $this->mParserOptions = ParserOptions::newFromContext( $this->getContext() );
1565                         $this->mParserOptions->setEditSection( false );
1566                 }
1567
1568                 if ( $options !== null && !empty( $options->isBogus ) ) {
1569                         // They're trying to restore the bogus pre-$wgUser PO. Do the right
1570                         // thing.
1571                         return wfSetVar( $this->mParserOptions, null, true );
1572                 } else {
1573                         return wfSetVar( $this->mParserOptions, $options );
1574                 }
1575         }
1576
1577         /**
1578          * Set the revision ID which will be seen by the wiki text parser
1579          * for things such as embedded {{REVISIONID}} variable use.
1580          *
1581          * @param int|null $revid An positive integer, or null
1582          * @return mixed Previous value
1583          */
1584         public function setRevisionId( $revid ) {
1585                 $val = is_null( $revid ) ? null : intval( $revid );
1586                 return wfSetVar( $this->mRevisionId, $val );
1587         }
1588
1589         /**
1590          * Get the displayed revision ID
1591          *
1592          * @return int
1593          */
1594         public function getRevisionId() {
1595                 return $this->mRevisionId;
1596         }
1597
1598         /**
1599          * Set the timestamp of the revision which will be displayed. This is used
1600          * to avoid a extra DB call in Skin::lastModified().
1601          *
1602          * @param string|null $timestamp
1603          * @return mixed Previous value
1604          */
1605         public function setRevisionTimestamp( $timestamp ) {
1606                 return wfSetVar( $this->mRevisionTimestamp, $timestamp );
1607         }
1608
1609         /**
1610          * Get the timestamp of displayed revision.
1611          * This will be null if not filled by setRevisionTimestamp().
1612          *
1613          * @return string|null
1614          */
1615         public function getRevisionTimestamp() {
1616                 return $this->mRevisionTimestamp;
1617         }
1618
1619         /**
1620          * Set the displayed file version
1621          *
1622          * @param File|bool $file
1623          * @return mixed Previous value
1624          */
1625         public function setFileVersion( $file ) {
1626                 $val = null;
1627                 if ( $file instanceof File && $file->exists() ) {
1628                         $val = [ 'time' => $file->getTimestamp(), 'sha1' => $file->getSha1() ];
1629                 }
1630                 return wfSetVar( $this->mFileVersion, $val, true );
1631         }
1632
1633         /**
1634          * Get the displayed file version
1635          *
1636          * @return array|null ('time' => MW timestamp, 'sha1' => sha1)
1637          */
1638         public function getFileVersion() {
1639                 return $this->mFileVersion;
1640         }
1641
1642         /**
1643          * Get the templates used on this page
1644          *
1645          * @return array (namespace => dbKey => revId)
1646          * @since 1.18
1647          */
1648         public function getTemplateIds() {
1649                 return $this->mTemplateIds;
1650         }
1651
1652         /**
1653          * Get the files used on this page
1654          *
1655          * @return array (dbKey => array('time' => MW timestamp or null, 'sha1' => sha1 or ''))
1656          * @since 1.18
1657          */
1658         public function getFileSearchOptions() {
1659                 return $this->mImageTimeKeys;
1660         }
1661
1662         /**
1663          * Convert wikitext to HTML and add it to the buffer
1664          * Default assumes that the current page title will be used.
1665          *
1666          * @param string $text
1667          * @param bool $linestart Is this the start of a line?
1668          * @param bool $interface Is this text in the user interface language?
1669          * @throws MWException
1670          */
1671         public function addWikiText( $text, $linestart = true, $interface = true ) {
1672                 $title = $this->getTitle(); // Work around E_STRICT
1673                 if ( !$title ) {
1674                         throw new MWException( 'Title is null' );
1675                 }
1676                 $this->addWikiTextTitle( $text, $title, $linestart, /*tidy*/false, $interface );
1677         }
1678
1679         /**
1680          * Add wikitext with a custom Title object
1681          *
1682          * @param string $text Wikitext
1683          * @param Title $title
1684          * @param bool $linestart Is this the start of a line?
1685          */
1686         public function addWikiTextWithTitle( $text, &$title, $linestart = true ) {
1687                 $this->addWikiTextTitle( $text, $title, $linestart );
1688         }
1689
1690         /**
1691          * Add wikitext with a custom Title object and tidy enabled.
1692          *
1693          * @param string $text Wikitext
1694          * @param Title $title
1695          * @param bool $linestart Is this the start of a line?
1696          */
1697         function addWikiTextTitleTidy( $text, &$title, $linestart = true ) {
1698                 $this->addWikiTextTitle( $text, $title, $linestart, true );
1699         }
1700
1701         /**
1702          * Add wikitext with tidy enabled
1703          *
1704          * @param string $text Wikitext
1705          * @param bool $linestart Is this the start of a line?
1706          */
1707         public function addWikiTextTidy( $text, $linestart = true ) {
1708                 $title = $this->getTitle();
1709                 $this->addWikiTextTitleTidy( $text, $title, $linestart );
1710         }
1711
1712         /**
1713          * Add wikitext with a custom Title object
1714          *
1715          * @param string $text Wikitext
1716          * @param Title $title
1717          * @param bool $linestart Is this the start of a line?
1718          * @param bool $tidy Whether to use tidy
1719          * @param bool $interface Whether it is an interface message
1720          *   (for example disables conversion)
1721          */
1722         public function addWikiTextTitle( $text, Title $title, $linestart,
1723                 $tidy = false, $interface = false
1724         ) {
1725                 global $wgParser;
1726
1727                 $popts = $this->parserOptions();
1728                 $oldTidy = $popts->setTidy( $tidy );
1729                 $popts->setInterfaceMessage( (bool)$interface );
1730
1731                 $parserOutput = $wgParser->getFreshParser()->parse(
1732                         $text, $title, $popts,
1733                         $linestart, true, $this->mRevisionId
1734                 );
1735
1736                 $popts->setTidy( $oldTidy );
1737
1738                 $this->addParserOutput( $parserOutput );
1739
1740         }
1741
1742         /**
1743          * Add a ParserOutput object, but without Html.
1744          *
1745          * @deprecated since 1.24, use addParserOutputMetadata() instead.
1746          * @param ParserOutput $parserOutput
1747          */
1748         public function addParserOutputNoText( $parserOutput ) {
1749                 wfDeprecated( __METHOD__, '1.24' );
1750                 $this->addParserOutputMetadata( $parserOutput );
1751         }
1752
1753         /**
1754          * Add all metadata associated with a ParserOutput object, but without the actual HTML. This
1755          * includes categories, language links, ResourceLoader modules, effects of certain magic words,
1756          * and so on.
1757          *
1758          * @since 1.24
1759          * @param ParserOutput $parserOutput
1760          */
1761         public function addParserOutputMetadata( $parserOutput ) {
1762                 $this->mLanguageLinks += $parserOutput->getLanguageLinks();
1763                 $this->addCategoryLinks( $parserOutput->getCategories() );
1764                 $this->setIndicators( $parserOutput->getIndicators() );
1765                 $this->mNewSectionLink = $parserOutput->getNewSection();
1766                 $this->mHideNewSectionLink = $parserOutput->getHideNewSection();
1767
1768                 if ( !$parserOutput->isCacheable() ) {
1769                         $this->enableClientCache( false );
1770                 }
1771                 $this->mNoGallery = $parserOutput->getNoGallery();
1772                 $this->mHeadItems = array_merge( $this->mHeadItems, $parserOutput->getHeadItems() );
1773                 $this->addModules( $parserOutput->getModules() );
1774                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1775                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1776                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1777                 $this->mPreventClickjacking = $this->mPreventClickjacking
1778                         || $parserOutput->preventClickjacking();
1779
1780                 // Template versioning...
1781                 foreach ( (array)$parserOutput->getTemplateIds() as $ns => $dbks ) {
1782                         if ( isset( $this->mTemplateIds[$ns] ) ) {
1783                                 $this->mTemplateIds[$ns] = $dbks + $this->mTemplateIds[$ns];
1784                         } else {
1785                                 $this->mTemplateIds[$ns] = $dbks;
1786                         }
1787                 }
1788                 // File versioning...
1789                 foreach ( (array)$parserOutput->getFileSearchOptions() as $dbk => $data ) {
1790                         $this->mImageTimeKeys[$dbk] = $data;
1791                 }
1792
1793                 // Hooks registered in the object
1794                 $parserOutputHooks = $this->getConfig()->get( 'ParserOutputHooks' );
1795                 foreach ( $parserOutput->getOutputHooks() as $hookInfo ) {
1796                         list( $hookName, $data ) = $hookInfo;
1797                         if ( isset( $parserOutputHooks[$hookName] ) ) {
1798                                 call_user_func( $parserOutputHooks[$hookName], $this, $parserOutput, $data );
1799                         }
1800                 }
1801
1802                 // enable OOUI if requested via ParserOutput
1803                 if ( $parserOutput->getEnableOOUI() ) {
1804                         $this->enableOOUI();
1805                 }
1806
1807                 // Link flags are ignored for now, but may in the future be
1808                 // used to mark individual language links.
1809                 $linkFlags = [];
1810                 Hooks::run( 'LanguageLinks', [ $this->getTitle(), &$this->mLanguageLinks, &$linkFlags ] );
1811                 Hooks::run( 'OutputPageParserOutput', [ &$this, $parserOutput ] );
1812         }
1813
1814         /**
1815          * Add the HTML and enhancements for it (like ResourceLoader modules) associated with a
1816          * ParserOutput object, without any other metadata.
1817          *
1818          * @since 1.24
1819          * @param ParserOutput $parserOutput
1820          */
1821         public function addParserOutputContent( $parserOutput ) {
1822                 $this->addParserOutputText( $parserOutput );
1823
1824                 $this->addModules( $parserOutput->getModules() );
1825                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1826                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1827
1828                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1829         }
1830
1831         /**
1832          * Add the HTML associated with a ParserOutput object, without any metadata.
1833          *
1834          * @since 1.24
1835          * @param ParserOutput $parserOutput
1836          */
1837         public function addParserOutputText( $parserOutput ) {
1838                 $text = $parserOutput->getText();
1839                 Hooks::run( 'OutputPageBeforeHTML', [ &$this, &$text ] );
1840                 $this->addHTML( $text );
1841         }
1842
1843         /**
1844          * Add everything from a ParserOutput object.
1845          *
1846          * @param ParserOutput $parserOutput
1847          */
1848         function addParserOutput( $parserOutput ) {
1849                 $this->addParserOutputMetadata( $parserOutput );
1850                 $parserOutput->setTOCEnabled( $this->mEnableTOC );
1851
1852                 // Touch section edit links only if not previously disabled
1853                 if ( $parserOutput->getEditSectionTokens() ) {
1854                         $parserOutput->setEditSectionTokens( $this->mEnableSectionEditLinks );
1855                 }
1856
1857                 $this->addParserOutputText( $parserOutput );
1858         }
1859
1860         /**
1861          * Add the output of a QuickTemplate to the output buffer
1862          *
1863          * @param QuickTemplate $template
1864          */
1865         public function addTemplate( &$template ) {
1866                 $this->addHTML( $template->getHTML() );
1867         }
1868
1869         /**
1870          * Parse wikitext and return the HTML.
1871          *
1872          * @param string $text
1873          * @param bool $linestart Is this the start of a line?
1874          * @param bool $interface Use interface language ($wgLang instead of
1875          *   $wgContLang) while parsing language sensitive magic words like GRAMMAR and PLURAL.
1876          *   This also disables LanguageConverter.
1877          * @param Language $language Target language object, will override $interface
1878          * @throws MWException
1879          * @return string HTML
1880          */
1881         public function parse( $text, $linestart = true, $interface = false, $language = null ) {
1882                 global $wgParser;
1883
1884                 if ( is_null( $this->getTitle() ) ) {
1885                         throw new MWException( 'Empty $mTitle in ' . __METHOD__ );
1886                 }
1887
1888                 $popts = $this->parserOptions();
1889                 if ( $interface ) {
1890                         $popts->setInterfaceMessage( true );
1891                 }
1892                 if ( $language !== null ) {
1893                         $oldLang = $popts->setTargetLanguage( $language );
1894                 }
1895
1896                 $parserOutput = $wgParser->getFreshParser()->parse(
1897                         $text, $this->getTitle(), $popts,
1898                         $linestart, true, $this->mRevisionId
1899                 );
1900
1901                 if ( $interface ) {
1902                         $popts->setInterfaceMessage( false );
1903                 }
1904                 if ( $language !== null ) {
1905                         $popts->setTargetLanguage( $oldLang );
1906                 }
1907
1908                 return $parserOutput->getText();
1909         }
1910
1911         /**
1912          * Parse wikitext, strip paragraphs, and return the HTML.
1913          *
1914          * @param string $text
1915          * @param bool $linestart Is this the start of a line?
1916          * @param bool $interface Use interface language ($wgLang instead of
1917          *   $wgContLang) while parsing language sensitive magic
1918          *   words like GRAMMAR and PLURAL
1919          * @return string HTML
1920          */
1921         public function parseInline( $text, $linestart = true, $interface = false ) {
1922                 $parsed = $this->parse( $text, $linestart, $interface );
1923                 return Parser::stripOuterParagraph( $parsed );
1924         }
1925
1926         /**
1927          * @param $maxage
1928          * @deprecated since 1.27 Use setCdnMaxage() instead
1929          */
1930         public function setSquidMaxage( $maxage ) {
1931                 $this->setCdnMaxage( $maxage );
1932         }
1933
1934         /**
1935          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header
1936          *
1937          * @param int $maxage Maximum cache time on the CDN, in seconds.
1938          */
1939         public function setCdnMaxage( $maxage ) {
1940                 $this->mCdnMaxage = min( $maxage, $this->mCdnMaxageLimit );
1941         }
1942
1943         /**
1944          * Lower the value of the "s-maxage" part of the "Cache-control" HTTP header
1945          *
1946          * @param int $maxage Maximum cache time on the CDN, in seconds
1947          * @since 1.27
1948          */
1949         public function lowerCdnMaxage( $maxage ) {
1950                 $this->mCdnMaxageLimit = min( $maxage, $this->mCdnMaxageLimit );
1951                 $this->setCdnMaxage( $this->mCdnMaxage );
1952         }
1953
1954         /**
1955          * Use enableClientCache(false) to force it to send nocache headers
1956          *
1957          * @param bool $state
1958          *
1959          * @return bool
1960          */
1961         public function enableClientCache( $state ) {
1962                 return wfSetVar( $this->mEnableClientCache, $state );
1963         }
1964
1965         /**
1966          * Get the list of cookies that will influence on the cache
1967          *
1968          * @return array
1969          */
1970         function getCacheVaryCookies() {
1971                 static $cookies;
1972                 if ( $cookies === null ) {
1973                         $config = $this->getConfig();
1974                         $cookies = array_merge(
1975                                 SessionManager::singleton()->getVaryCookies(),
1976                                 [
1977                                         'forceHTTPS',
1978                                 ],
1979                                 $config->get( 'CacheVaryCookies' )
1980                         );
1981                         Hooks::run( 'GetCacheVaryCookies', [ $this, &$cookies ] );
1982                 }
1983                 return $cookies;
1984         }
1985
1986         /**
1987          * Check if the request has a cache-varying cookie header
1988          * If it does, it's very important that we don't allow public caching
1989          *
1990          * @return bool
1991          */
1992         function haveCacheVaryCookies() {
1993                 $request = $this->getRequest();
1994                 foreach ( $this->getCacheVaryCookies() as $cookieName ) {
1995                         if ( $request->getCookie( $cookieName, '', '' ) !== '' ) {
1996                                 wfDebug( __METHOD__ . ": found $cookieName\n" );
1997                                 return true;
1998                         }
1999                 }
2000                 wfDebug( __METHOD__ . ": no cache-varying cookies found\n" );
2001                 return false;
2002         }
2003
2004         /**
2005          * Add an HTTP header that will influence on the cache
2006          *
2007          * @param string $header Header name
2008          * @param string[]|null $option Options for the Key header. See
2009          * https://datatracker.ietf.org/doc/draft-fielding-http-key/
2010          * for the list of valid options.
2011          */
2012         public function addVaryHeader( $header, array $option = null ) {
2013                 if ( !array_key_exists( $header, $this->mVaryHeader ) ) {
2014                         $this->mVaryHeader[$header] = [];
2015                 }
2016                 if ( !is_array( $option ) ) {
2017                         $option = [];
2018                 }
2019                 $this->mVaryHeader[$header] = array_unique( array_merge( $this->mVaryHeader[$header], $option ) );
2020         }
2021
2022         /**
2023          * Return a Vary: header on which to vary caches. Based on the keys of $mVaryHeader,
2024          * such as Accept-Encoding or Cookie
2025          *
2026          * @return string
2027          */
2028         public function getVaryHeader() {
2029                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2030                         $this->addVaryHeader( $header, $options );
2031                 }
2032                 return 'Vary: ' . implode( ', ', array_keys( $this->mVaryHeader ) );
2033         }
2034
2035         /**
2036          * Get a complete Key header
2037          *
2038          * @return string
2039          */
2040         public function getKeyHeader() {
2041                 $cvCookies = $this->getCacheVaryCookies();
2042
2043                 $cookiesOption = [];
2044                 foreach ( $cvCookies as $cookieName ) {
2045                         $cookiesOption[] = 'param=' . $cookieName;
2046                 }
2047                 $this->addVaryHeader( 'Cookie', $cookiesOption );
2048
2049                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2050                         $this->addVaryHeader( $header, $options );
2051                 }
2052
2053                 $headers = [];
2054                 foreach ( $this->mVaryHeader as $header => $option ) {
2055                         $newheader = $header;
2056                         if ( is_array( $option ) && count( $option ) > 0 ) {
2057                                 $newheader .= ';' . implode( ';', $option );
2058                         }
2059                         $headers[] = $newheader;
2060                 }
2061                 $key = 'Key: ' . implode( ',', $headers );
2062
2063                 return $key;
2064         }
2065
2066         /**
2067          * T23672: Add Accept-Language to Vary and Key headers
2068          * if there's no 'variant' parameter existed in GET.
2069          *
2070          * For example:
2071          *   /w/index.php?title=Main_page should always be served; but
2072          *   /w/index.php?title=Main_page&variant=zh-cn should never be served.
2073          */
2074         function addAcceptLanguage() {
2075                 $title = $this->getTitle();
2076                 if ( !$title instanceof Title ) {
2077                         return;
2078                 }
2079
2080                 $lang = $title->getPageLanguage();
2081                 if ( !$this->getRequest()->getCheck( 'variant' ) && $lang->hasVariants() ) {
2082                         $variants = $lang->getVariants();
2083                         $aloption = [];
2084                         foreach ( $variants as $variant ) {
2085                                 if ( $variant === $lang->getCode() ) {
2086                                         continue;
2087                                 } else {
2088                                         $aloption[] = 'substr=' . $variant;
2089
2090                                         // IE and some other browsers use BCP 47 standards in
2091                                         // their Accept-Language header, like "zh-CN" or "zh-Hant".
2092                                         // We should handle these too.
2093                                         $variantBCP47 = wfBCP47( $variant );
2094                                         if ( $variantBCP47 !== $variant ) {
2095                                                 $aloption[] = 'substr=' . $variantBCP47;
2096                                         }
2097                                 }
2098                         }
2099                         $this->addVaryHeader( 'Accept-Language', $aloption );
2100                 }
2101         }
2102
2103         /**
2104          * Set a flag which will cause an X-Frame-Options header appropriate for
2105          * edit pages to be sent. The header value is controlled by
2106          * $wgEditPageFrameOptions.
2107          *
2108          * This is the default for special pages. If you display a CSRF-protected
2109          * form on an ordinary view page, then you need to call this function.
2110          *
2111          * @param bool $enable
2112          */
2113         public function preventClickjacking( $enable = true ) {
2114                 $this->mPreventClickjacking = $enable;
2115         }
2116
2117         /**
2118          * Turn off frame-breaking. Alias for $this->preventClickjacking(false).
2119          * This can be called from pages which do not contain any CSRF-protected
2120          * HTML form.
2121          */
2122         public function allowClickjacking() {
2123                 $this->mPreventClickjacking = false;
2124         }
2125
2126         /**
2127          * Get the prevent-clickjacking flag
2128          *
2129          * @since 1.24
2130          * @return bool
2131          */
2132         public function getPreventClickjacking() {
2133                 return $this->mPreventClickjacking;
2134         }
2135
2136         /**
2137          * Get the X-Frame-Options header value (without the name part), or false
2138          * if there isn't one. This is used by Skin to determine whether to enable
2139          * JavaScript frame-breaking, for clients that don't support X-Frame-Options.
2140          *
2141          * @return string
2142          */
2143         public function getFrameOptions() {
2144                 $config = $this->getConfig();
2145                 if ( $config->get( 'BreakFrames' ) ) {
2146                         return 'DENY';
2147                 } elseif ( $this->mPreventClickjacking && $config->get( 'EditPageFrameOptions' ) ) {
2148                         return $config->get( 'EditPageFrameOptions' );
2149                 }
2150                 return false;
2151         }
2152
2153         /**
2154          * Send cache control HTTP headers
2155          */
2156         public function sendCacheControl() {
2157                 $response = $this->getRequest()->response();
2158                 $config = $this->getConfig();
2159                 if ( $config->get( 'UseETag' ) && $this->mETag ) {
2160                         $response->header( "ETag: $this->mETag" );
2161                 }
2162
2163                 $this->addVaryHeader( 'Cookie' );
2164                 $this->addAcceptLanguage();
2165
2166                 # don't serve compressed data to clients who can't handle it
2167                 # maintain different caches for logged-in users and non-logged in ones
2168                 $response->header( $this->getVaryHeader() );
2169
2170                 if ( $config->get( 'UseKeyHeader' ) ) {
2171                         $response->header( $this->getKeyHeader() );
2172                 }
2173
2174                 if ( $this->mEnableClientCache ) {
2175                         if (
2176                                 $config->get( 'UseSquid' ) &&
2177                                 !$response->hasCookies() &&
2178                                 !SessionManager::getGlobalSession()->isPersistent() &&
2179                                 !$this->isPrintable() &&
2180                                 $this->mCdnMaxage != 0 &&
2181                                 !$this->haveCacheVaryCookies()
2182                         ) {
2183                                 if ( $config->get( 'UseESI' ) ) {
2184                                         # We'll purge the proxy cache explicitly, but require end user agents
2185                                         # to revalidate against the proxy on each visit.
2186                                         # Surrogate-Control controls our CDN, Cache-Control downstream caches
2187                                         wfDebug( __METHOD__ . ": proxy caching with ESI; {$this->mLastModified} **", 'private' );
2188                                         # start with a shorter timeout for initial testing
2189                                         # header( 'Surrogate-Control: max-age=2678400+2678400, content="ESI/1.0"');
2190                                         $response->header( 'Surrogate-Control: max-age=' . $config->get( 'SquidMaxage' )
2191                                                 . '+' . $this->mCdnMaxage . ', content="ESI/1.0"' );
2192                                         $response->header( 'Cache-Control: s-maxage=0, must-revalidate, max-age=0' );
2193                                 } else {
2194                                         # We'll purge the proxy cache for anons explicitly, but require end user agents
2195                                         # to revalidate against the proxy on each visit.
2196                                         # IMPORTANT! The CDN needs to replace the Cache-Control header with
2197                                         # Cache-Control: s-maxage=0, must-revalidate, max-age=0
2198                                         wfDebug( __METHOD__ . ": local proxy caching; {$this->mLastModified} **", 'private' );
2199                                         # start with a shorter timeout for initial testing
2200                                         # header( "Cache-Control: s-maxage=2678400, must-revalidate, max-age=0" );
2201                                         $response->header( 'Cache-Control: s-maxage=' . $this->mCdnMaxage
2202                                                 . ', must-revalidate, max-age=0' );
2203                                 }
2204                         } else {
2205                                 # We do want clients to cache if they can, but they *must* check for updates
2206                                 # on revisiting the page.
2207                                 wfDebug( __METHOD__ . ": private caching; {$this->mLastModified} **", 'private' );
2208                                 $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2209                                 $response->header( "Cache-Control: private, must-revalidate, max-age=0" );
2210                         }
2211                         if ( $this->mLastModified ) {
2212                                 $response->header( "Last-Modified: {$this->mLastModified}" );
2213                         }
2214                 } else {
2215                         wfDebug( __METHOD__ . ": no caching **", 'private' );
2216
2217                         # In general, the absence of a last modified header should be enough to prevent
2218                         # the client from using its cache. We send a few other things just to make sure.
2219                         $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2220                         $response->header( 'Cache-Control: no-cache, no-store, max-age=0, must-revalidate' );
2221                         $response->header( 'Pragma: no-cache' );
2222                 }
2223         }
2224
2225         /**
2226          * Finally, all the text has been munged and accumulated into
2227          * the object, let's actually output it:
2228          */
2229         public function output() {
2230                 if ( $this->mDoNothing ) {
2231                         return;
2232                 }
2233
2234                 $response = $this->getRequest()->response();
2235                 $config = $this->getConfig();
2236
2237                 if ( $this->mRedirect != '' ) {
2238                         # Standards require redirect URLs to be absolute
2239                         $this->mRedirect = wfExpandUrl( $this->mRedirect, PROTO_CURRENT );
2240
2241                         $redirect = $this->mRedirect;
2242                         $code = $this->mRedirectCode;
2243
2244                         if ( Hooks::run( "BeforePageRedirect", [ $this, &$redirect, &$code ] ) ) {
2245                                 if ( $code == '301' || $code == '303' ) {
2246                                         if ( !$config->get( 'DebugRedirects' ) ) {
2247                                                 $response->statusHeader( $code );
2248                                         }
2249                                         $this->mLastModified = wfTimestamp( TS_RFC2822 );
2250                                 }
2251                                 if ( $config->get( 'VaryOnXFP' ) ) {
2252                                         $this->addVaryHeader( 'X-Forwarded-Proto' );
2253                                 }
2254                                 $this->sendCacheControl();
2255
2256                                 $response->header( "Content-Type: text/html; charset=utf-8" );
2257                                 if ( $config->get( 'DebugRedirects' ) ) {
2258                                         $url = htmlspecialchars( $redirect );
2259                                         print "<html>\n<head>\n<title>Redirect</title>\n</head>\n<body>\n";
2260                                         print "<p>Location: <a href=\"$url\">$url</a></p>\n";
2261                                         print "</body>\n</html>\n";
2262                                 } else {
2263                                         $response->header( 'Location: ' . $redirect );
2264                                 }
2265                         }
2266
2267                         return;
2268                 } elseif ( $this->mStatusCode ) {
2269                         $response->statusHeader( $this->mStatusCode );
2270                 }
2271
2272                 # Buffer output; final headers may depend on later processing
2273                 ob_start();
2274
2275                 $response->header( 'Content-type: ' . $config->get( 'MimeType' ) . '; charset=UTF-8' );
2276                 $response->header( 'Content-language: ' . $config->get( 'LanguageCode' ) );
2277
2278                 // Avoid Internet Explorer "compatibility view" in IE 8-10, so that
2279                 // jQuery etc. can work correctly.
2280                 $response->header( 'X-UA-Compatible: IE=Edge' );
2281
2282                 // Prevent framing, if requested
2283                 $frameOptions = $this->getFrameOptions();
2284                 if ( $frameOptions ) {
2285                         $response->header( "X-Frame-Options: $frameOptions" );
2286                 }
2287
2288                 if ( $this->mArticleBodyOnly ) {
2289                         echo $this->mBodytext;
2290                 } else {
2291                         $sk = $this->getSkin();
2292                         // add skin specific modules
2293                         $modules = $sk->getDefaultModules();
2294
2295                         // Enforce various default modules for all skins
2296                         $coreModules = [
2297                                 // Keep this list as small as possible
2298                                 'site',
2299                                 'mediawiki.page.startup',
2300                                 'mediawiki.user',
2301                         ];
2302
2303                         // Support for high-density display images if enabled
2304                         if ( $config->get( 'ResponsiveImages' ) ) {
2305                                 $coreModules[] = 'mediawiki.hidpi';
2306                         }
2307
2308                         $this->addModules( $coreModules );
2309                         foreach ( $modules as $group ) {
2310                                 $this->addModules( $group );
2311                         }
2312                         MWDebug::addModules( $this );
2313
2314                         // Hook that allows last minute changes to the output page, e.g.
2315                         // adding of CSS or Javascript by extensions.
2316                         Hooks::run( 'BeforePageDisplay', [ &$this, &$sk ] );
2317
2318                         $sk->outputPage();
2319                 }
2320
2321                 // This hook allows last minute changes to final overall output by modifying output buffer
2322                 Hooks::run( 'AfterFinalPageOutput', [ $this ] );
2323
2324                 $this->sendCacheControl();
2325
2326                 ob_end_flush();
2327
2328         }
2329
2330         /**
2331          * Prepare this object to display an error page; disable caching and
2332          * indexing, clear the current text and redirect, set the page's title
2333          * and optionally an custom HTML title (content of the "<title>" tag).
2334          *
2335          * @param string|Message $pageTitle Will be passed directly to setPageTitle()
2336          * @param string|Message $htmlTitle Will be passed directly to setHTMLTitle();
2337          *                   optional, if not passed the "<title>" attribute will be
2338          *                   based on $pageTitle
2339          */
2340         public function prepareErrorPage( $pageTitle, $htmlTitle = false ) {
2341                 $this->setPageTitle( $pageTitle );
2342                 if ( $htmlTitle !== false ) {
2343                         $this->setHTMLTitle( $htmlTitle );
2344                 }
2345                 $this->setRobotPolicy( 'noindex,nofollow' );
2346                 $this->setArticleRelated( false );
2347                 $this->enableClientCache( false );
2348                 $this->mRedirect = '';
2349                 $this->clearSubtitle();
2350                 $this->clearHTML();
2351         }
2352
2353         /**
2354          * Output a standard error page
2355          *
2356          * showErrorPage( 'titlemsg', 'pagetextmsg' );
2357          * showErrorPage( 'titlemsg', 'pagetextmsg', array( 'param1', 'param2' ) );
2358          * showErrorPage( 'titlemsg', $messageObject );
2359          * showErrorPage( $titleMessageObject, $messageObject );
2360          *
2361          * @param string|Message $title Message key (string) for page title, or a Message object
2362          * @param string|Message $msg Message key (string) for page text, or a Message object
2363          * @param array $params Message parameters; ignored if $msg is a Message object
2364          */
2365         public function showErrorPage( $title, $msg, $params = [] ) {
2366                 if ( !$title instanceof Message ) {
2367                         $title = $this->msg( $title );
2368                 }
2369
2370                 $this->prepareErrorPage( $title );
2371
2372                 if ( $msg instanceof Message ) {
2373                         if ( $params !== [] ) {
2374                                 trigger_error( 'Argument ignored: $params. The message parameters argument '
2375                                         . 'is discarded when the $msg argument is a Message object instead of '
2376                                         . 'a string.', E_USER_NOTICE );
2377                         }
2378                         $this->addHTML( $msg->parseAsBlock() );
2379                 } else {
2380                         $this->addWikiMsgArray( $msg, $params );
2381                 }
2382
2383                 $this->returnToMain();
2384         }
2385
2386         /**
2387          * Output a standard permission error page
2388          *
2389          * @param array $errors Error message keys
2390          * @param string $action Action that was denied or null if unknown
2391          */
2392         public function showPermissionsErrorPage( array $errors, $action = null ) {
2393                 // For some action (read, edit, create and upload), display a "login to do this action"
2394                 // error if all of the following conditions are met:
2395                 // 1. the user is not logged in
2396                 // 2. the only error is insufficient permissions (i.e. no block or something else)
2397                 // 3. the error can be avoided simply by logging in
2398                 if ( in_array( $action, [ 'read', 'edit', 'createpage', 'createtalk', 'upload' ] )
2399                         && $this->getUser()->isAnon() && count( $errors ) == 1 && isset( $errors[0][0] )
2400                         && ( $errors[0][0] == 'badaccess-groups' || $errors[0][0] == 'badaccess-group0' )
2401                         && ( User::groupHasPermission( 'user', $action )
2402                         || User::groupHasPermission( 'autoconfirmed', $action ) )
2403                 ) {
2404                         $displayReturnto = null;
2405
2406                         # Due to bug 32276, if a user does not have read permissions,
2407                         # $this->getTitle() will just give Special:Badtitle, which is
2408                         # not especially useful as a returnto parameter. Use the title
2409                         # from the request instead, if there was one.
2410                         $request = $this->getRequest();
2411                         $returnto = Title::newFromText( $request->getVal( 'title', '' ) );
2412                         if ( $action == 'edit' ) {
2413                                 $msg = 'whitelistedittext';
2414                                 $displayReturnto = $returnto;
2415                         } elseif ( $action == 'createpage' || $action == 'createtalk' ) {
2416                                 $msg = 'nocreatetext';
2417                         } elseif ( $action == 'upload' ) {
2418                                 $msg = 'uploadnologintext';
2419                         } else { # Read
2420                                 $msg = 'loginreqpagetext';
2421                                 $displayReturnto = Title::newMainPage();
2422                         }
2423
2424                         $query = [];
2425
2426                         if ( $returnto ) {
2427                                 $query['returnto'] = $returnto->getPrefixedText();
2428
2429                                 if ( !$request->wasPosted() ) {
2430                                         $returntoquery = $request->getValues();
2431                                         unset( $returntoquery['title'] );
2432                                         unset( $returntoquery['returnto'] );
2433                                         unset( $returntoquery['returntoquery'] );
2434                                         $query['returntoquery'] = wfArrayToCgi( $returntoquery );
2435                                 }
2436                         }
2437                         $loginLink = Linker::linkKnown(
2438                                 SpecialPage::getTitleFor( 'Userlogin' ),
2439                                 $this->msg( 'loginreqlink' )->escaped(),
2440                                 [],
2441                                 $query
2442                         );
2443
2444                         $this->prepareErrorPage( $this->msg( 'loginreqtitle' ) );
2445                         $this->addHTML( $this->msg( $msg )->rawParams( $loginLink )->parse() );
2446
2447                         # Don't return to a page the user can't read otherwise
2448                         # we'll end up in a pointless loop
2449                         if ( $displayReturnto && $displayReturnto->userCan( 'read', $this->getUser() ) ) {
2450                                 $this->returnToMain( null, $displayReturnto );
2451                         }
2452                 } else {
2453                         $this->prepareErrorPage( $this->msg( 'permissionserrors' ) );
2454                         $this->addWikiText( $this->formatPermissionsErrorMessage( $errors, $action ) );
2455                 }
2456         }
2457
2458         /**
2459          * Display an error page indicating that a given version of MediaWiki is
2460          * required to use it
2461          *
2462          * @param mixed $version The version of MediaWiki needed to use the page
2463          */
2464         public function versionRequired( $version ) {
2465                 $this->prepareErrorPage( $this->msg( 'versionrequired', $version ) );
2466
2467                 $this->addWikiMsg( 'versionrequiredtext', $version );
2468                 $this->returnToMain();
2469         }
2470
2471         /**
2472          * Format a list of error messages
2473          *
2474          * @param array $errors Array of arrays returned by Title::getUserPermissionsErrors
2475          * @param string $action Action that was denied or null if unknown
2476          * @return string The wikitext error-messages, formatted into a list.
2477          */
2478         public function formatPermissionsErrorMessage( array $errors, $action = null ) {
2479                 if ( $action == null ) {
2480                         $text = $this->msg( 'permissionserrorstext', count( $errors ) )->plain() . "\n\n";
2481                 } else {
2482                         $action_desc = $this->msg( "action-$action" )->plain();
2483                         $text = $this->msg(
2484                                 'permissionserrorstext-withaction',
2485                                 count( $errors ),
2486                                 $action_desc
2487                         )->plain() . "\n\n";
2488                 }
2489
2490                 if ( count( $errors ) > 1 ) {
2491                         $text .= '<ul class="permissions-errors">' . "\n";
2492
2493                         foreach ( $errors as $error ) {
2494                                 $text .= '<li>';
2495                                 $text .= call_user_func_array( [ $this, 'msg' ], $error )->plain();
2496                                 $text .= "</li>\n";
2497                         }
2498                         $text .= '</ul>';
2499                 } else {
2500                         $text .= "<div class=\"permissions-errors\">\n" .
2501                                         call_user_func_array( [ $this, 'msg' ], reset( $errors ) )->plain() .
2502                                         "\n</div>";
2503                 }
2504
2505                 return $text;
2506         }
2507
2508         /**
2509          * Display a page stating that the Wiki is in read-only mode.
2510          * Should only be called after wfReadOnly() has returned true.
2511          *
2512          * Historically, this function was used to show the source of the page that the user
2513          * was trying to edit and _also_ permissions error messages. The relevant code was
2514          * moved into EditPage in 1.19 (r102024 / d83c2a431c2a) and removed here in 1.25.
2515          *
2516          * @deprecated since 1.25; throw the exception directly
2517          * @throws ReadOnlyError
2518          */
2519         public function readOnlyPage() {
2520                 if ( func_num_args() > 0 ) {
2521                         throw new MWException( __METHOD__ . ' no longer accepts arguments since 1.25.' );
2522                 }
2523
2524                 throw new ReadOnlyError;
2525         }
2526
2527         /**
2528          * Turn off regular page output and return an error response
2529          * for when rate limiting has triggered.
2530          *
2531          * @deprecated since 1.25; throw the exception directly
2532          */
2533         public function rateLimited() {
2534                 wfDeprecated( __METHOD__, '1.25' );
2535                 throw new ThrottledError;
2536         }
2537
2538         /**
2539          * Show a warning about slave lag
2540          *
2541          * If the lag is higher than $wgSlaveLagCritical seconds,
2542          * then the warning is a bit more obvious. If the lag is
2543          * lower than $wgSlaveLagWarning, then no warning is shown.
2544          *
2545          * @param int $lag Slave lag
2546          */
2547         public function showLagWarning( $lag ) {
2548                 $config = $this->getConfig();
2549                 if ( $lag >= $config->get( 'SlaveLagWarning' ) ) {
2550                         $message = $lag < $config->get( 'SlaveLagCritical' )
2551                                 ? 'lag-warn-normal'
2552                                 : 'lag-warn-high';
2553                         $wrap = Html::rawElement( 'div', [ 'class' => "mw-{$message}" ], "\n$1\n" );
2554                         $this->wrapWikiMsg( "$wrap\n", [ $message, $this->getLanguage()->formatNum( $lag ) ] );
2555                 }
2556         }
2557
2558         public function showFatalError( $message ) {
2559                 $this->prepareErrorPage( $this->msg( 'internalerror' ) );
2560
2561                 $this->addHTML( $message );
2562         }
2563
2564         public function showUnexpectedValueError( $name, $val ) {
2565                 $this->showFatalError( $this->msg( 'unexpected', $name, $val )->text() );
2566         }
2567
2568         public function showFileCopyError( $old, $new ) {
2569                 $this->showFatalError( $this->msg( 'filecopyerror', $old, $new )->text() );
2570         }
2571
2572         public function showFileRenameError( $old, $new ) {
2573                 $this->showFatalError( $this->msg( 'filerenameerror', $old, $new )->text() );
2574         }
2575
2576         public function showFileDeleteError( $name ) {
2577                 $this->showFatalError( $this->msg( 'filedeleteerror', $name )->text() );
2578         }
2579
2580         public function showFileNotFoundError( $name ) {
2581                 $this->showFatalError( $this->msg( 'filenotfound', $name )->text() );
2582         }
2583
2584         /**
2585          * Add a "return to" link pointing to a specified title
2586          *
2587          * @param Title $title Title to link
2588          * @param array $query Query string parameters
2589          * @param string $text Text of the link (input is not escaped)
2590          * @param array $options Options array to pass to Linker
2591          */
2592         public function addReturnTo( $title, array $query = [], $text = null, $options = [] ) {
2593                 $link = $this->msg( 'returnto' )->rawParams(
2594                         Linker::link( $title, $text, [], $query, $options ) )->escaped();
2595                 $this->addHTML( "<p id=\"mw-returnto\">{$link}</p>\n" );
2596         }
2597
2598         /**
2599          * Add a "return to" link pointing to a specified title,
2600          * or the title indicated in the request, or else the main page
2601          *
2602          * @param mixed $unused
2603          * @param Title|string $returnto Title or String to return to
2604          * @param string $returntoquery Query string for the return to link
2605          */
2606         public function returnToMain( $unused = null, $returnto = null, $returntoquery = null ) {
2607                 if ( $returnto == null ) {
2608                         $returnto = $this->getRequest()->getText( 'returnto' );
2609                 }
2610
2611                 if ( $returntoquery == null ) {
2612                         $returntoquery = $this->getRequest()->getText( 'returntoquery' );
2613                 }
2614
2615                 if ( $returnto === '' ) {
2616                         $returnto = Title::newMainPage();
2617                 }
2618
2619                 if ( is_object( $returnto ) ) {
2620                         $titleObj = $returnto;
2621                 } else {
2622                         $titleObj = Title::newFromText( $returnto );
2623                 }
2624                 if ( !is_object( $titleObj ) ) {
2625                         $titleObj = Title::newMainPage();
2626                 }
2627
2628                 $this->addReturnTo( $titleObj, wfCgiToArray( $returntoquery ) );
2629         }
2630
2631         /**
2632          * @param Skin $sk The given Skin
2633          * @param bool $includeStyle Unused
2634          * @return string The doctype, opening "<html>", and head element.
2635          */
2636         public function headElement( Skin $sk, $includeStyle = true ) {
2637                 global $wgContLang;
2638
2639                 $userdir = $this->getLanguage()->getDir();
2640                 $sitedir = $wgContLang->getDir();
2641
2642                 $ret = Html::htmlHeader( $sk->getHtmlElementAttributes() );
2643
2644                 if ( $this->getHTMLTitle() == '' ) {
2645                         $this->setHTMLTitle( $this->msg( 'pagetitle', $this->getPageTitle() )->inContentLanguage() );
2646                 }
2647
2648                 $openHead = Html::openElement( 'head' );
2649                 if ( $openHead ) {
2650                         # Don't bother with the newline if $head == ''
2651                         $ret .= "$openHead\n";
2652                 }
2653
2654                 if ( !Html::isXmlMimeType( $this->getConfig()->get( 'MimeType' ) ) ) {
2655                         // Add <meta charset="UTF-8">
2656                         // This should be before <title> since it defines the charset used by
2657                         // text including the text inside <title>.
2658                         // The spec recommends defining XHTML5's charset using the XML declaration
2659                         // instead of meta.
2660                         // Our XML declaration is output by Html::htmlHeader.
2661                         // http://www.whatwg.org/html/semantics.html#attr-meta-http-equiv-content-type
2662                         // http://www.whatwg.org/html/semantics.html#charset
2663                         $ret .= Html::element( 'meta', [ 'charset' => 'UTF-8' ] ) . "\n";
2664                 }
2665
2666                 $ret .= Html::element( 'title', null, $this->getHTMLTitle() ) . "\n";
2667                 $ret .= $this->getInlineHeadScripts() . "\n";
2668                 $ret .= $this->buildCssLinks() . "\n";
2669                 $ret .= $this->getExternalHeadScripts() . "\n";
2670
2671                 foreach ( $this->getHeadLinksArray() as $item ) {
2672                         $ret .= $item . "\n";
2673                 }
2674
2675                 foreach ( $this->mHeadItems as $item ) {
2676                         $ret .= $item . "\n";
2677                 }
2678
2679                 $closeHead = Html::closeElement( 'head' );
2680                 if ( $closeHead ) {
2681                         $ret .= "$closeHead\n";
2682                 }
2683
2684                 $bodyClasses = [];
2685                 $bodyClasses[] = 'mediawiki';
2686
2687                 # Classes for LTR/RTL directionality support
2688                 $bodyClasses[] = $userdir;
2689                 $bodyClasses[] = "sitedir-$sitedir";
2690
2691                 if ( $this->getLanguage()->capitalizeAllNouns() ) {
2692                         # A <body> class is probably not the best way to do this . . .
2693                         $bodyClasses[] = 'capitalize-all-nouns';
2694                 }
2695
2696                 $bodyClasses[] = $sk->getPageClasses( $this->getTitle() );
2697                 $bodyClasses[] = 'skin-' . Sanitizer::escapeClass( $sk->getSkinName() );
2698                 $bodyClasses[] =
2699                         'action-' . Sanitizer::escapeClass( Action::getActionName( $this->getContext() ) );
2700
2701                 $bodyAttrs = [];
2702                 // While the implode() is not strictly needed, it's used for backwards compatibility
2703                 // (this used to be built as a string and hooks likely still expect that).
2704                 $bodyAttrs['class'] = implode( ' ', $bodyClasses );
2705
2706                 // Allow skins and extensions to add body attributes they need
2707                 $sk->addToBodyAttributes( $this, $bodyAttrs );
2708                 Hooks::run( 'OutputPageBodyAttributes', [ $this, $sk, &$bodyAttrs ] );
2709
2710                 $ret .= Html::openElement( 'body', $bodyAttrs ) . "\n";
2711
2712                 return $ret;
2713         }
2714
2715         /**
2716          * Get a ResourceLoader object associated with this OutputPage
2717          *
2718          * @return ResourceLoader
2719          */
2720         public function getResourceLoader() {
2721                 if ( is_null( $this->mResourceLoader ) ) {
2722                         $this->mResourceLoader = new ResourceLoader(
2723                                 $this->getConfig(),
2724                                 LoggerFactory::getInstance( 'resourceloader' )
2725                         );
2726                 }
2727                 return $this->mResourceLoader;
2728         }
2729
2730         /**
2731          * Construct neccecary html and loader preset states to load modules on a page.
2732          *
2733          * Use getHtmlFromLoaderLinks() to convert this array to HTML.
2734          *
2735          * @param array|string $modules One or more module names
2736          * @param string $only ResourceLoaderModule TYPE_ class constant
2737          * @param array $extraQuery [optional] Array with extra query parameters for the request
2738          * @return array A list of HTML strings and array of client loader preset states
2739          */
2740         public function makeResourceLoaderLink( $modules, $only, array $extraQuery = [] ) {
2741                 $modules = (array)$modules;
2742
2743                 $links = [
2744                         // List of html strings
2745                         'html' => [],
2746                         // Associative array of module names and their states
2747                         'states' => [],
2748                 ];
2749
2750                 if ( !count( $modules ) ) {
2751                         return $links;
2752                 }
2753
2754                 if ( count( $modules ) > 1 ) {
2755                         // Remove duplicate module requests
2756                         $modules = array_unique( $modules );
2757                         // Sort module names so requests are more uniform
2758                         sort( $modules );
2759
2760                         if ( ResourceLoader::inDebugMode() ) {
2761                                 // Recursively call us for every item
2762                                 foreach ( $modules as $name ) {
2763                                         $link = $this->makeResourceLoaderLink( $name, $only, $extraQuery );
2764                                         $links['html'] = array_merge( $links['html'], $link['html'] );
2765                                         $links['states'] += $link['states'];
2766                                 }
2767                                 return $links;
2768                         }
2769                 }
2770
2771                 if ( !is_null( $this->mTarget ) ) {
2772                         $extraQuery['target'] = $this->mTarget;
2773                 }
2774
2775                 // Create keyed-by-source and then keyed-by-group list of module objects from modules list
2776                 $sortedModules = [];
2777                 $resourceLoader = $this->getResourceLoader();
2778                 foreach ( $modules as $name ) {
2779                         $module = $resourceLoader->getModule( $name );
2780                         # Check that we're allowed to include this module on this page
2781                         if ( !$module
2782                                 || ( $module->getOrigin() > $this->getAllowedModules( ResourceLoaderModule::TYPE_SCRIPTS )
2783                                         && $only == ResourceLoaderModule::TYPE_SCRIPTS )
2784                                 || ( $module->getOrigin() > $this->getAllowedModules( ResourceLoaderModule::TYPE_STYLES )
2785                                         && $only == ResourceLoaderModule::TYPE_STYLES )
2786                                 || ( $module->getOrigin() > $this->getAllowedModules( ResourceLoaderModule::TYPE_COMBINED )
2787                                         && $only == ResourceLoaderModule::TYPE_COMBINED )
2788                                 || ( $this->mTarget && !in_array( $this->mTarget, $module->getTargets() ) )
2789                         ) {
2790                                 continue;
2791                         }
2792
2793                         $sortedModules[$module->getSource()][$module->getGroup()][$name] = $module;
2794                 }
2795
2796                 foreach ( $sortedModules as $source => $groups ) {
2797                         foreach ( $groups as $group => $grpModules ) {
2798                                 // Special handling for user-specific groups
2799                                 $user = null;
2800                                 if ( ( $group === 'user' || $group === 'private' ) && $this->getUser()->isLoggedIn() ) {
2801                                         $user = $this->getUser()->getName();
2802                                 }
2803
2804                                 // Create a fake request based on the one we are about to make so modules return
2805                                 // correct timestamp and emptiness data
2806                                 $query = ResourceLoader::makeLoaderQuery(
2807                                         [], // modules; not determined yet
2808                                         $this->getLanguage()->getCode(),
2809                                         $this->getSkin()->getSkinName(),
2810                                         $user,
2811                                         null, // version; not determined yet
2812                                         ResourceLoader::inDebugMode(),
2813                                         $only === ResourceLoaderModule::TYPE_COMBINED ? null : $only,
2814                                         $this->isPrintable(),
2815                                         $this->getRequest()->getBool( 'handheld' ),
2816                                         $extraQuery
2817                                 );
2818                                 $context = new ResourceLoaderContext( $resourceLoader, new FauxRequest( $query ) );
2819
2820                                 // Extract modules that know they're empty and see if we have one or more
2821                                 // raw modules
2822                                 $isRaw = false;
2823                                 foreach ( $grpModules as $key => $module ) {
2824                                         // Inline empty modules: since they're empty, just mark them as 'ready' (bug 46857)
2825                                         // If we're only getting the styles, we don't need to do anything for empty modules.
2826                                         if ( $module->isKnownEmpty( $context ) ) {
2827                                                 unset( $grpModules[$key] );
2828                                                 if ( $only !== ResourceLoaderModule::TYPE_STYLES ) {
2829                                                         $links['states'][$key] = 'ready';
2830                                                 }
2831                                         }
2832
2833                                         $isRaw |= $module->isRaw();
2834                                 }
2835
2836                                 // If there are no non-empty modules, skip this group
2837                                 if ( count( $grpModules ) === 0 ) {
2838                                         continue;
2839                                 }
2840
2841                                 // Inline private modules. These can't be loaded through load.php for security
2842                                 // reasons, see bug 34907. Note that these modules should be loaded from
2843                                 // getExternalHeadScripts() before the first loader call. Otherwise other modules can't
2844                                 // properly use them as dependencies (bug 30914)
2845                                 if ( $group === 'private' ) {
2846                                         if ( $only == ResourceLoaderModule::TYPE_STYLES ) {
2847                                                 $links['html'][] = Html::inlineStyle(
2848                                                         $resourceLoader->makeModuleResponse( $context, $grpModules )
2849                                                 );
2850                                         } else {
2851                                                 $links['html'][] = ResourceLoader::makeInlineScript(
2852                                                         $resourceLoader->makeModuleResponse( $context, $grpModules )
2853                                                 );
2854                                         }
2855                                         continue;
2856                                 }
2857
2858                                 // Special handling for the user group; because users might change their stuff
2859                                 // on-wiki like user pages, or user preferences; we need to find the highest
2860                                 // timestamp of these user-changeable modules so we can ensure cache misses on change
2861                                 // This should NOT be done for the site group (bug 27564) because anons get that too
2862                                 // and we shouldn't be putting timestamps in CDN-cached HTML
2863                                 $version = null;
2864                                 if ( $group === 'user' ) {
2865                                         $query['version'] = $resourceLoader->getCombinedVersion( $context, array_keys( $grpModules ) );
2866                                 }
2867
2868                                 $query['modules'] = ResourceLoader::makePackedModulesString( array_keys( $grpModules ) );
2869                                 $moduleContext = new ResourceLoaderContext( $resourceLoader, new FauxRequest( $query ) );
2870                                 $url = $resourceLoader->createLoaderURL( $source, $moduleContext, $extraQuery );
2871
2872                                 // Automatically select style/script elements
2873                                 if ( $only === ResourceLoaderModule::TYPE_STYLES ) {
2874                                         $link = Html::linkedStyle( $url );
2875                                 } else {
2876                                         if ( $context->getRaw() || $isRaw ) {
2877                                                 // Startup module can't load itself, needs to use <script> instead of mw.loader.load
2878                                                 $link = Html::element( 'script', [
2879                                                         // In SpecialJavaScriptTest, QUnit must load synchronous
2880                                                         'async' => !isset( $extraQuery['sync'] ),
2881                                                         'src' => $url
2882                                                 ] );
2883                                         } else {
2884                                                 $link = ResourceLoader::makeInlineScript(
2885                                                         Xml::encodeJsCall( 'mw.loader.load', [ $url ] )
2886                                                 );
2887                                         }
2888
2889                                         // For modules requested directly in the html via <script> or mw.loader.load
2890                                         // tell mw.loader they are being loading to prevent duplicate requests.
2891                                         foreach ( $grpModules as $key => $module ) {
2892                                                 // Don't output state=loading for the startup module.
2893                                                 if ( $key !== 'startup' ) {
2894                                                         $links['states'][$key] = 'loading';
2895                                                 }
2896                                         }
2897                                 }
2898
2899                                 if ( $group == 'noscript' ) {
2900                                         $links['html'][] = Html::rawElement( 'noscript', [], $link );
2901                                 } else {
2902                                         $links['html'][] = $link;
2903                                 }
2904                         }
2905                 }
2906
2907                 return $links;
2908         }
2909
2910         /**
2911          * Build html output from an array of links from makeResourceLoaderLink.
2912          * @param array $links
2913          * @return string HTML
2914          */
2915         protected static function getHtmlFromLoaderLinks( array $links ) {
2916                 $html = [];
2917                 $states = [];
2918                 foreach ( $links as $link ) {
2919                         if ( !is_array( $link ) ) {
2920                                 $html[] = $link;
2921                         } else {
2922                                 $html = array_merge( $html, $link['html'] );
2923                                 $states += $link['states'];
2924                         }
2925                 }
2926                 // Filter out empty values
2927                 $html = array_filter( $html, 'strlen' );
2928
2929                 if ( count( $states ) ) {
2930                         array_unshift( $html, ResourceLoader::makeInlineScript(
2931                                 ResourceLoader::makeLoaderStateScript( $states )
2932                         ) );
2933                 }
2934
2935                 return WrappedString::join( "\n", $html );
2936         }
2937
2938         /**
2939          * JS stuff to put in the "<head>". This is the startup module, config
2940          * vars and modules marked with position 'top'
2941          *
2942          * @return string HTML fragment
2943          */
2944         function getHeadScripts() {
2945                 return $this->getInlineHeadScripts() . $this->getExternalHeadScripts();
2946         }
2947
2948         /**
2949          * <script src="..."> tags for "<head>". This is the startup module
2950          * and other modules marked with position 'top'.
2951          *
2952          * @return string HTML fragment
2953          */
2954         function getExternalHeadScripts() {
2955                 $links = [];
2956
2957                 // Startup - this provides the client with the module
2958                 // manifest and loads jquery and mediawiki base modules
2959                 $links[] = $this->makeResourceLoaderLink( 'startup', ResourceLoaderModule::TYPE_SCRIPTS );
2960
2961                 return self::getHtmlFromLoaderLinks( $links );
2962         }
2963
2964         /**
2965          * <script>...</script> tags to put in "<head>".
2966          *
2967          * @return string HTML fragment
2968          */
2969         function getInlineHeadScripts() {
2970                 $links = [];
2971
2972                 // Client profile classes for <html>. Allows for easy hiding/showing of UI components.
2973                 // Must be done synchronously on every page to avoid flashes of wrong content.
2974                 // Note: This class distinguishes MediaWiki-supported JavaScript from the rest.
2975                 // The "rest" includes browsers that support JavaScript but not supported by our runtime.
2976                 // For the performance benefit of the majority, this is added unconditionally here and is
2977                 // then fixed up by the startup module for unsupported browsers.
2978                 $links[] = Html::inlineScript(
2979                         'document.documentElement.className = document.documentElement.className'
2980                         . '.replace( /(^|\s)client-nojs(\s|$)/, "$1client-js$2" );'
2981                 );
2982
2983                 // Load config before anything else
2984                 $links[] = ResourceLoader::makeInlineScript(
2985                         ResourceLoader::makeConfigSetScript( $this->getJSVars() )
2986                 );
2987
2988                 // Load embeddable private modules before any loader links
2989                 // This needs to be TYPE_COMBINED so these modules are properly wrapped
2990                 // in mw.loader.implement() calls and deferred until mw.user is available
2991                 $embedScripts = [ 'user.options' ];
2992                 $links[] = $this->makeResourceLoaderLink(
2993                         $embedScripts,
2994                         ResourceLoaderModule::TYPE_COMBINED
2995                 );
2996                 // Separate user.tokens as otherwise caching will be allowed (T84960)
2997                 $links[] = $this->makeResourceLoaderLink(
2998                         'user.tokens',
2999                         ResourceLoaderModule::TYPE_COMBINED
3000                 );
3001
3002                 // Modules requests - let the client calculate dependencies and batch requests as it likes
3003                 // Only load modules that have marked themselves for loading at the top
3004                 $modules = $this->getModules( true, 'top' );
3005                 if ( $modules ) {
3006                         $links[] = ResourceLoader::makeInlineScript(
3007                                 Xml::encodeJsCall( 'mw.loader.load', [ $modules ] )
3008                         );
3009                 }
3010
3011                 // "Scripts only" modules marked for top inclusion
3012                 $links[] = $this->makeResourceLoaderLink(
3013                         $this->getModuleScripts( true, 'top' ),
3014                         ResourceLoaderModule::TYPE_SCRIPTS
3015                 );
3016
3017                 return self::getHtmlFromLoaderLinks( $links );
3018         }
3019
3020         /**
3021          * JS stuff to put at the 'bottom', which goes at the bottom of the `<body>`.
3022          * These are modules marked with position 'bottom', legacy scripts ($this->mScripts),
3023          * site JS, and user JS.
3024          *
3025          * @param bool $unused Previously used to let this method change its output based
3026          *  on whether it was called by getExternalHeadScripts() or getBottomScripts().
3027          * @return string
3028          */
3029         function getScriptsForBottomQueue( $unused = null ) {
3030                 // Scripts "only" requests marked for bottom inclusion
3031                 // If we're in the <head>, use load() calls rather than <script src="..."> tags
3032                 $links = [];
3033
3034                 $links[] = $this->makeResourceLoaderLink( $this->getModuleScripts( true, 'bottom' ),
3035                         ResourceLoaderModule::TYPE_SCRIPTS
3036                 );
3037
3038                 // Modules requests - let the client calculate dependencies and batch requests as it likes
3039                 // Only load modules that have marked themselves for loading at the bottom
3040                 $modules = $this->getModules( true, 'bottom' );
3041                 if ( $modules ) {
3042                         $links[] = ResourceLoader::makeInlineScript(
3043                                 Xml::encodeJsCall( 'mw.loader.load', [ $modules ] )
3044                         );
3045                 }
3046
3047                 // Legacy Scripts
3048                 $links[] = $this->mScripts;
3049
3050                 // Add user JS if enabled
3051                 // This must use TYPE_COMBINED instead of only=scripts so that its request is handled by
3052                 // mw.loader.implement() which ensures that execution is scheduled after the "site" module.
3053                 if ( $this->getConfig()->get( 'AllowUserJs' )
3054                         && $this->getUser()->isLoggedIn()
3055                         && $this->getTitle()
3056                         && $this->getTitle()->isJsSubpage()
3057                         && $this->userCanPreview()
3058                 ) {
3059                         // We're on a preview of a JS subpage. Exclude this page from the user module (T28283)
3060                         // and include the draft contents as a raw script instead.
3061                         $links[] = $this->makeResourceLoaderLink( 'user', ResourceLoaderModule::TYPE_COMBINED,
3062                                 [ 'excludepage' => $this->getTitle()->getPrefixedDBkey() ]
3063                         );
3064                         // Load the previewed JS
3065                         $links[] = ResourceLoader::makeInlineScript(
3066                                 Xml::encodeJsCall( 'mw.loader.using', [
3067                                         [ 'user', 'site' ],
3068                                         new XmlJsCode(
3069                                                 'function () {'
3070                                                         . Xml::encodeJsCall( '$.globalEval', [
3071                                                                 $this->getRequest()->getText( 'wpTextbox1' )
3072                                                         ] )
3073                                                         . '}'
3074                                         )
3075                                 ] )
3076                         );
3077
3078                         // FIXME: If the user is previewing, say, ./vector.js, his ./common.js will be loaded
3079                         // asynchronously and may arrive *after* the inline script here. So the previewed code
3080                         // may execute before ./common.js runs. Normally, ./common.js runs before ./vector.js.
3081                         // Similarly, when previewing ./common.js and the user module does arrive first,
3082                         // it will arrive without common.js and the inline script runs after.
3083                         // Thus running common after the excluded subpage.
3084                 } else {
3085                         // Include the user module normally, i.e., raw to avoid it being wrapped in a closure.
3086                         $links[] = $this->makeResourceLoaderLink( 'user', ResourceLoaderModule::TYPE_COMBINED );
3087                 }
3088
3089                 // Group JS is only enabled if site JS is enabled.
3090                 $links[] = $this->makeResourceLoaderLink(
3091                         'user.groups',
3092                         ResourceLoaderModule::TYPE_COMBINED
3093                 );
3094
3095                 return self::getHtmlFromLoaderLinks( $links );
3096         }
3097
3098         /**
3099          * JS stuff to put at the bottom of the "<body>"
3100          * @return string
3101          */
3102         function getBottomScripts() {
3103                 return $this->getScriptsForBottomQueue();
3104         }
3105
3106         /**
3107          * Get the javascript config vars to include on this page
3108          *
3109          * @return array Array of javascript config vars
3110          * @since 1.23
3111          */
3112         public function getJsConfigVars() {
3113                 return $this->mJsConfigVars;
3114         }
3115
3116         /**
3117          * Add one or more variables to be set in mw.config in JavaScript
3118          *
3119          * @param string|array $keys Key or array of key/value pairs
3120          * @param mixed $value [optional] Value of the configuration variable
3121          */
3122         public function addJsConfigVars( $keys, $value = null ) {
3123                 if ( is_array( $keys ) ) {
3124                         foreach ( $keys as $key => $value ) {
3125                                 $this->mJsConfigVars[$key] = $value;
3126                         }
3127                         return;
3128                 }
3129
3130                 $this->mJsConfigVars[$keys] = $value;
3131         }
3132
3133         /**
3134          * Get an array containing the variables to be set in mw.config in JavaScript.
3135          *
3136          * Do not add things here which can be evaluated in ResourceLoaderStartUpModule
3137          * - in other words, page-independent/site-wide variables (without state).
3138          * You will only be adding bloat to the html page and causing page caches to
3139          * have to be purged on configuration changes.
3140          * @return array
3141          */
3142         public function getJSVars() {
3143                 global $wgContLang;
3144
3145                 $curRevisionId = 0;
3146                 $articleId = 0;
3147                 $canonicalSpecialPageName = false; # bug 21115
3148
3149                 $title = $this->getTitle();
3150                 $ns = $title->getNamespace();
3151                 $canonicalNamespace = MWNamespace::exists( $ns )
3152                         ? MWNamespace::getCanonicalName( $ns )
3153                         : $title->getNsText();
3154
3155                 $sk = $this->getSkin();
3156                 // Get the relevant title so that AJAX features can use the correct page name
3157                 // when making API requests from certain special pages (bug 34972).
3158                 $relevantTitle = $sk->getRelevantTitle();
3159                 $relevantUser = $sk->getRelevantUser();
3160
3161                 if ( $ns == NS_SPECIAL ) {
3162                         list( $canonicalSpecialPageName, /*...*/ ) =
3163                                 SpecialPageFactory::resolveAlias( $title->getDBkey() );
3164                 } elseif ( $this->canUseWikiPage() ) {
3165                         $wikiPage = $this->getWikiPage();
3166                         $curRevisionId = $wikiPage->getLatest();
3167                         $articleId = $wikiPage->getId();
3168                 }
3169
3170                 $lang = $title->getPageViewLanguage();
3171
3172                 // Pre-process information
3173                 $separatorTransTable = $lang->separatorTransformTable();
3174                 $separatorTransTable = $separatorTransTable ? $separatorTransTable : [];
3175                 $compactSeparatorTransTable = [
3176                         implode( "\t", array_keys( $separatorTransTable ) ),
3177                         implode( "\t", $separatorTransTable ),
3178                 ];
3179                 $digitTransTable = $lang->digitTransformTable();
3180                 $digitTransTable = $digitTransTable ? $digitTransTable : [];
3181                 $compactDigitTransTable = [
3182                         implode( "\t", array_keys( $digitTransTable ) ),
3183                         implode( "\t", $digitTransTable ),
3184                 ];
3185
3186                 $user = $this->getUser();
3187
3188                 $vars = [
3189                         'wgCanonicalNamespace' => $canonicalNamespace,
3190                         'wgCanonicalSpecialPageName' => $canonicalSpecialPageName,
3191                         'wgNamespaceNumber' => $title->getNamespace(),
3192                         'wgPageName' => $title->getPrefixedDBkey(),
3193                         'wgTitle' => $title->getText(),
3194                         'wgCurRevisionId' => $curRevisionId,
3195                         'wgRevisionId' => (int)$this->getRevisionId(),
3196                         'wgArticleId' => $articleId,
3197                         'wgIsArticle' => $this->isArticle(),
3198                         'wgIsRedirect' => $title->isRedirect(),
3199                         'wgAction' => Action::getActionName( $this->getContext() ),
3200                         'wgUserName' => $user->isAnon() ? null : $user->getName(),
3201                         'wgUserGroups' => $user->getEffectiveGroups(),
3202                         'wgCategories' => $this->getCategories(),
3203                         'wgBreakFrames' => $this->getFrameOptions() == 'DENY',
3204                         'wgPageContentLanguage' => $lang->getCode(),
3205                         'wgPageContentModel' => $title->getContentModel(),
3206                         'wgSeparatorTransformTable' => $compactSeparatorTransTable,
3207                         'wgDigitTransformTable' => $compactDigitTransTable,
3208                         'wgDefaultDateFormat' => $lang->getDefaultDateFormat(),
3209                         'wgMonthNames' => $lang->getMonthNamesArray(),
3210                         'wgMonthNamesShort' => $lang->getMonthAbbreviationsArray(),
3211                         'wgRelevantPageName' => $relevantTitle->getPrefixedDBkey(),
3212                         'wgRelevantArticleId' => $relevantTitle->getArticleID(),
3213                 ];
3214
3215                 if ( $user->isLoggedIn() ) {
3216                         $vars['wgUserId'] = $user->getId();
3217                         $vars['wgUserEditCount'] = $user->getEditCount();
3218                         $userReg = wfTimestampOrNull( TS_UNIX, $user->getRegistration() );
3219                         $vars['wgUserRegistration'] = $userReg !== null ? ( $userReg * 1000 ) : null;
3220                         // Get the revision ID of the oldest new message on the user's talk
3221                         // page. This can be used for constructing new message alerts on
3222                         // the client side.
3223                         $vars['wgUserNewMsgRevisionId'] = $user->getNewMessageRevisionId();
3224                 }
3225
3226                 if ( $wgContLang->hasVariants() ) {
3227                         $vars['wgUserVariant'] = $wgContLang->getPreferredVariant();
3228                 }
3229                 // Same test as SkinTemplate
3230                 $vars['wgIsProbablyEditable'] = $title->quickUserCan( 'edit', $user )
3231                         && ( $title->exists() || $title->quickUserCan( 'create', $user ) );
3232
3233                 foreach ( $title->getRestrictionTypes() as $type ) {
3234                         $vars['wgRestriction' . ucfirst( $type )] = $title->getRestrictions( $type );
3235                 }
3236
3237                 if ( $title->isMainPage() ) {
3238                         $vars['wgIsMainPage'] = true;
3239                 }
3240
3241                 if ( $this->mRedirectedFrom ) {
3242                         $vars['wgRedirectedFrom'] = $this->mRedirectedFrom->getPrefixedDBkey();
3243                 }
3244
3245                 if ( $relevantUser ) {
3246                         $vars['wgRelevantUserName'] = $relevantUser->getName();
3247                 }
3248
3249                 // Allow extensions to add their custom variables to the mw.config map.
3250                 // Use the 'ResourceLoaderGetConfigVars' hook if the variable is not
3251                 // page-dependant but site-wide (without state).
3252                 // Alternatively, you may want to use OutputPage->addJsConfigVars() instead.
3253                 Hooks::run( 'MakeGlobalVariablesScript', [ &$vars, $this ] );
3254
3255                 // Merge in variables from addJsConfigVars last
3256                 return array_merge( $vars, $this->getJsConfigVars() );
3257         }
3258
3259         /**
3260          * To make it harder for someone to slip a user a fake
3261          * user-JavaScript or user-CSS preview, a random token
3262          * is associated with the login session. If it's not
3263          * passed back with the preview request, we won't render
3264          * the code.
3265          *
3266          * @return bool
3267          */
3268         public function userCanPreview() {
3269                 $request = $this->getRequest();
3270                 if (
3271                         $request->getVal( 'action' ) !== 'submit' ||
3272                         !$request->getCheck( 'wpPreview' ) ||
3273                         !$request->wasPosted()
3274                 ) {
3275                         return false;
3276                 }
3277
3278                 $user = $this->getUser();
3279                 if ( !$user->matchEditToken( $request->getVal( 'wpEditToken' ) ) ) {
3280                         return false;
3281                 }
3282
3283                 $title = $this->getTitle();
3284                 if ( !$title->isJsSubpage() && !$title->isCssSubpage() ) {
3285                         return false;
3286                 }
3287                 if ( !$title->isSubpageOf( $user->getUserPage() ) ) {
3288                         // Don't execute another user's CSS or JS on preview (T85855)
3289                         return false;
3290                 }
3291
3292                 $errors = $title->getUserPermissionsErrors( 'edit', $user );
3293                 if ( count( $errors ) !== 0 ) {
3294                         return false;
3295                 }
3296
3297                 return true;
3298         }
3299
3300         /**
3301          * @return array Array in format "link name or number => 'link html'".
3302          */
3303         public function getHeadLinksArray() {
3304                 global $wgVersion;
3305
3306                 $tags = [];
3307                 $config = $this->getConfig();
3308
3309                 $canonicalUrl = $this->mCanonicalUrl;
3310
3311                 $tags['meta-generator'] = Html::element( 'meta', [
3312                         'name' => 'generator',
3313                         'content' => "MediaWiki $wgVersion",
3314                 ] );
3315
3316                 if ( $config->get( 'ReferrerPolicy' ) !== false ) {
3317                         $tags['meta-referrer'] = Html::element( 'meta', [
3318                                 'name' => 'referrer',
3319                                 'content' => $config->get( 'ReferrerPolicy' )
3320                         ] );
3321                 }
3322
3323                 $p = "{$this->mIndexPolicy},{$this->mFollowPolicy}";
3324                 if ( $p !== 'index,follow' ) {
3325                         // http://www.robotstxt.org/wc/meta-user.html
3326                         // Only show if it's different from the default robots policy
3327                         $tags['meta-robots'] = Html::element( 'meta', [
3328                                 'name' => 'robots',
3329                                 'content' => $p,
3330                         ] );
3331                 }
3332
3333                 foreach ( $this->mMetatags as $tag ) {
3334                         if ( 0 == strcasecmp( 'http:', substr( $tag[0], 0, 5 ) ) ) {
3335                                 $a = 'http-equiv';
3336                                 $tag[0] = substr( $tag[0], 5 );
3337                         } else {
3338                                 $a = 'name';
3339                         }
3340                         $tagName = "meta-{$tag[0]}";
3341                         if ( isset( $tags[$tagName] ) ) {
3342                                 $tagName .= $tag[1];
3343                         }
3344                         $tags[$tagName] = Html::element( 'meta',
3345                                 [
3346                                         $a => $tag[0],
3347                                         'content' => $tag[1]
3348                                 ]
3349                         );
3350                 }
3351
3352                 foreach ( $this->mLinktags as $tag ) {
3353                         $tags[] = Html::element( 'link', $tag );
3354                 }
3355
3356                 # Universal edit button
3357                 if ( $config->get( 'UniversalEditButton' ) && $this->isArticleRelated() ) {
3358                         $user = $this->getUser();
3359                         if ( $this->getTitle()->quickUserCan( 'edit', $user )
3360                                 && ( $this->getTitle()->exists() ||
3361                                         $this->getTitle()->quickUserCan( 'create', $user ) )
3362                         ) {
3363                                 // Original UniversalEditButton
3364                                 $msg = $this->msg( 'edit' )->text();
3365                                 $tags['universal-edit-button'] = Html::element( 'link', [
3366                                         'rel' => 'alternate',
3367                                         'type' => 'application/x-wiki',
3368                                         'title' => $msg,
3369                                         'href' => $this->getTitle()->getEditURL(),
3370                                 ] );
3371                                 // Alternate edit link
3372                                 $tags['alternative-edit'] = Html::element( 'link', [
3373                                         'rel' => 'edit',
3374                                         'title' => $msg,
3375                                         'href' => $this->getTitle()->getEditURL(),
3376                                 ] );
3377                         }
3378                 }
3379
3380                 # Generally the order of the favicon and apple-touch-icon links
3381                 # should not matter, but Konqueror (3.5.9 at least) incorrectly
3382                 # uses whichever one appears later in the HTML source. Make sure
3383                 # apple-touch-icon is specified first to avoid this.
3384                 if ( $config->get( 'AppleTouchIcon' ) !== false ) {
3385                         $tags['apple-touch-icon'] = Html::element( 'link', [
3386                                 'rel' => 'apple-touch-icon',
3387                                 'href' => $config->get( 'AppleTouchIcon' )
3388                         ] );
3389                 }
3390
3391                 if ( $config->get( 'Favicon' ) !== false ) {
3392                         $tags['favicon'] = Html::element( 'link', [
3393                                 'rel' => 'shortcut icon',
3394                                 'href' => $config->get( 'Favicon' )
3395                         ] );
3396                 }
3397
3398                 # OpenSearch description link
3399                 $tags['opensearch'] = Html::element( 'link', [
3400                         'rel' => 'search',
3401                         'type' => 'application/opensearchdescription+xml',
3402                         'href' => wfScript( 'opensearch_desc' ),
3403                         'title' => $this->msg( 'opensearch-desc' )->inContentLanguage()->text(),
3404                 ] );
3405
3406                 if ( $config->get( 'EnableAPI' ) ) {
3407                         # Real Simple Discovery link, provides auto-discovery information
3408                         # for the MediaWiki API (and potentially additional custom API
3409                         # support such as WordPress or Twitter-compatible APIs for a
3410                         # blogging extension, etc)
3411                         $tags['rsd'] = Html::element( 'link', [
3412                                 'rel' => 'EditURI',
3413                                 'type' => 'application/rsd+xml',
3414                                 // Output a protocol-relative URL here if $wgServer is protocol-relative.
3415                                 // Whether RSD accepts relative or protocol-relative URLs is completely
3416                                 // undocumented, though.
3417                                 'href' => wfExpandUrl( wfAppendQuery(
3418                                         wfScript( 'api' ),
3419                                         [ 'action' => 'rsd' ] ),
3420                                         PROTO_RELATIVE
3421                                 ),
3422                         ] );
3423                 }
3424
3425                 # Language variants
3426                 if ( !$config->get( 'DisableLangConversion' ) ) {
3427                         $lang = $this->getTitle()->getPageLanguage();
3428                         if ( $lang->hasVariants() ) {
3429                                 $variants = $lang->getVariants();
3430                                 foreach ( $variants as $variant ) {
3431                                         $tags["variant-$variant"] = Html::element( 'link', [
3432                                                 'rel' => 'alternate',
3433                                                 'hreflang' => wfBCP47( $variant ),
3434                                                 'href' => $this->getTitle()->getLocalURL(
3435                                                         [ 'variant' => $variant ] )
3436                                                 ]
3437                                         );
3438                                 }
3439                                 # x-default link per https://support.google.com/webmasters/answer/189077?hl=en
3440                                 $tags["variant-x-default"] = Html::element( 'link', [
3441                                         'rel' => 'alternate',
3442                                         'hreflang' => 'x-default',
3443                                         'href' => $this->getTitle()->getLocalURL() ] );
3444                         }
3445                 }
3446
3447                 # Copyright
3448                 if ( $this->copyrightUrl !== null ) {
3449                         $copyright = $this->copyrightUrl;
3450                 } else {
3451                         $copyright = '';
3452                         if ( $config->get( 'RightsPage' ) ) {
3453                                 $copy = Title::newFromText( $config->get( 'RightsPage' ) );
3454
3455                                 if ( $copy ) {
3456                                         $copyright = $copy->getLocalURL();
3457                                 }
3458                         }
3459
3460                         if ( !$copyright && $config->get( 'RightsUrl' ) ) {
3461                                 $copyright = $config->get( 'RightsUrl' );
3462                         }
3463                 }
3464
3465                 if ( $copyright ) {
3466                         $tags['copyright'] = Html::element( 'link', [
3467                                 'rel' => 'copyright',
3468                                 'href' => $copyright ]
3469                         );
3470                 }
3471
3472                 # Feeds
3473                 if ( $config->get( 'Feed' ) ) {
3474                         $feedLinks = [];
3475
3476                         foreach ( $this->getSyndicationLinks() as $format => $link ) {
3477                                 # Use the page name for the title.  In principle, this could
3478                                 # lead to issues with having the same name for different feeds
3479                                 # corresponding to the same page, but we can't avoid that at
3480                                 # this low a level.
3481
3482                                 $feedLinks[] = $this->feedLink(
3483                                         $format,
3484                                         $link,
3485                                         # Used messages: 'page-rss-feed' and 'page-atom-feed' (for an easier grep)
3486                                         $this->msg(
3487                                                 "page-{$format}-feed", $this->getTitle()->getPrefixedText()
3488                                         )->text()
3489                                 );
3490                         }
3491
3492                         # Recent changes feed should appear on every page (except recentchanges,
3493                         # that would be redundant). Put it after the per-page feed to avoid
3494                         # changing existing behavior. It's still available, probably via a
3495                         # menu in your browser. Some sites might have a different feed they'd
3496                         # like to promote instead of the RC feed (maybe like a "Recent New Articles"
3497                         # or "Breaking news" one). For this, we see if $wgOverrideSiteFeed is defined.
3498                         # If so, use it instead.
3499                         $sitename = $config->get( 'Sitename' );
3500                         if ( $config->get( 'OverrideSiteFeed' ) ) {
3501                                 foreach ( $config->get( 'OverrideSiteFeed' ) as $type => $feedUrl ) {
3502                                         // Note, this->feedLink escapes the url.
3503                                         $feedLinks[] = $this->feedLink(
3504                                                 $type,
3505                                                 $feedUrl,
3506                                                 $this->msg( "site-{$type}-feed", $sitename )->text()
3507                                         );
3508                                 }
3509                         } elseif ( !$this->getTitle()->isSpecial( 'Recentchanges' ) ) {
3510                                 $rctitle = SpecialPage::getTitleFor( 'Recentchanges' );
3511                                 foreach ( $config->get( 'AdvertisedFeedTypes' ) as $format ) {
3512                                         $feedLinks[] = $this->feedLink(
3513                                                 $format,
3514                                                 $rctitle->getLocalURL( [ 'feed' => $format ] ),
3515                                                 # For grep: 'site-rss-feed', 'site-atom-feed'
3516                                                 $this->msg( "site-{$format}-feed", $sitename )->text()
3517                                         );
3518                                 }
3519                         }
3520
3521                         # Allow extensions to change the list pf feeds. This hook is primarily for changing,
3522                         # manipulating or removing existing feed tags. If you want to add new feeds, you should
3523                         # use OutputPage::addFeedLink() instead.
3524                         Hooks::run( 'AfterBuildFeedLinks', [ &$feedLinks ] );
3525
3526                         $tags += $feedLinks;
3527                 }
3528
3529                 # Canonical URL
3530                 if ( $config->get( 'EnableCanonicalServerLink' ) ) {
3531                         if ( $canonicalUrl !== false ) {
3532                                 $canonicalUrl = wfExpandUrl( $canonicalUrl, PROTO_CANONICAL );
3533                         } else {
3534                                 if ( $this->isArticleRelated() ) {
3535                                         // This affects all requests where "setArticleRelated" is true. This is
3536                                         // typically all requests that show content (query title, curid, oldid, diff),
3537                                         // and all wikipage actions (edit, delete, purge, info, history etc.).
3538                                         // It does not apply to File pages and Special pages.
3539                                         // 'history' and 'info' actions address page metadata rather than the page
3540                                         // content itself, so they may not be canonicalized to the view page url.
3541                                         // TODO: this ought to be better encapsulated in the Action class.
3542                                         $action = Action::getActionName( $this->getContext() );
3543                                         if ( in_array( $action, [ 'history', 'info' ] ) ) {
3544                                                 $query = "action={$action}";
3545                                         } else {
3546                                                 $query = '';
3547                                         }
3548                                         $canonicalUrl = $this->getTitle()->getCanonicalURL( $query );
3549                                 } else {
3550                                         $reqUrl = $this->getRequest()->getRequestURL();
3551                                         $canonicalUrl = wfExpandUrl( $reqUrl, PROTO_CANONICAL );
3552                                 }
3553                         }
3554                 }
3555                 if ( $canonicalUrl !== false ) {
3556                         $tags[] = Html::element( 'link', [
3557                                 'rel' => 'canonical',
3558                                 'href' => $canonicalUrl
3559                         ] );
3560                 }
3561
3562                 return $tags;
3563         }
3564
3565         /**
3566          * @return string HTML tag links to be put in the header.
3567          * @deprecated since 1.24 Use OutputPage::headElement or if you have to,
3568          *   OutputPage::getHeadLinksArray directly.
3569          */
3570         public function getHeadLinks() {
3571                 wfDeprecated( __METHOD__, '1.24' );
3572                 return implode( "\n", $this->getHeadLinksArray() );
3573         }
3574
3575         /**
3576          * Generate a "<link rel/>" for a feed.
3577          *
3578          * @param string $type Feed type
3579          * @param string $url URL to the feed
3580          * @param string $text Value of the "title" attribute
3581          * @return string HTML fragment
3582          */
3583         private function feedLink( $type, $url, $text ) {
3584                 return Html::element( 'link', [
3585                         'rel' => 'alternate',
3586                         'type' => "application/$type+xml",
3587                         'title' => $text,
3588                         'href' => $url ]
3589                 );
3590         }
3591
3592         /**
3593          * Add a local or specified stylesheet, with the given media options.
3594          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3595          *
3596          * @param string $style URL to the file
3597          * @param string $media To specify a media type, 'screen', 'printable', 'handheld' or any.
3598          * @param string $condition For IE conditional comments, specifying an IE version
3599          * @param string $dir Set to 'rtl' or 'ltr' for direction-specific sheets
3600          */
3601         public function addStyle( $style, $media = '', $condition = '', $dir = '' ) {
3602                 $options = [];
3603                 if ( $media ) {
3604                         $options['media'] = $media;
3605                 }
3606                 if ( $condition ) {
3607                         $options['condition'] = $condition;
3608                 }
3609                 if ( $dir ) {
3610                         $options['dir'] = $dir;
3611                 }
3612                 $this->styles[$style] = $options;
3613         }
3614
3615         /**
3616          * Adds inline CSS styles
3617          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3618          *
3619          * @param mixed $style_css Inline CSS
3620          * @param string $flip Set to 'flip' to flip the CSS if needed
3621          */
3622         public function addInlineStyle( $style_css, $flip = 'noflip' ) {
3623                 if ( $flip === 'flip' && $this->getLanguage()->isRTL() ) {
3624                         # If wanted, and the interface is right-to-left, flip the CSS
3625                         $style_css = CSSJanus::transform( $style_css, true, false );
3626                 }
3627                 $this->mInlineStyles .= Html::inlineStyle( $style_css );
3628         }
3629
3630         /**
3631          * Build a set of "<link>" elements for the stylesheets specified in the $this->styles array.
3632          * These will be applied to various media & IE conditionals.
3633          *
3634          * @return string
3635          */
3636         public function buildCssLinks() {
3637                 global $wgContLang;
3638
3639                 $this->getSkin()->setupSkinUserCss( $this );
3640
3641                 // Add ResourceLoader styles
3642                 // Split the styles into these groups
3643                 $styles = [
3644                         'other' => [],
3645                         'user' => [],
3646                         'site' => [],
3647                         'private' => [],
3648                         'noscript' => []
3649                 ];
3650                 $links = [];
3651                 $otherTags = []; // Tags to append after the normal <link> tags
3652                 $resourceLoader = $this->getResourceLoader();
3653
3654                 $moduleStyles = $this->getModuleStyles();
3655
3656                 // Per-site custom styles
3657                 $moduleStyles[] = 'site';
3658                 $moduleStyles[] = 'noscript';
3659                 $moduleStyles[] = 'user.groups';
3660
3661                 // Per-user custom styles
3662                 if ( $this->getConfig()->get( 'AllowUserCss' ) && $this->getTitle()->isCssSubpage()
3663                         && $this->userCanPreview()
3664                 ) {
3665                         // We're on a preview of a CSS subpage
3666                         // Exclude this page from the user module in case it's in there (bug 26283)
3667                         $link = $this->makeResourceLoaderLink( 'user', ResourceLoaderModule::TYPE_STYLES,
3668                                 [ 'excludepage' => $this->getTitle()->getPrefixedDBkey() ]
3669                         );
3670                         $otherTags = array_merge( $otherTags, $link['html'] );
3671
3672                         // Load the previewed CSS
3673                         // If needed, Janus it first. This is user-supplied CSS, so it's
3674                         // assumed to be right for the content language directionality.
3675                         $previewedCSS = $this->getRequest()->getText( 'wpTextbox1' );
3676                         if ( $this->getLanguage()->getDir() !== $wgContLang->getDir() ) {
3677                                 $previewedCSS = CSSJanus::transform( $previewedCSS, true, false );
3678                         }
3679                         $otherTags[] = Html::inlineStyle( $previewedCSS );
3680                 } else {
3681                         // Load the user styles normally
3682                         $moduleStyles[] = 'user';
3683                 }
3684
3685                 // Per-user preference styles
3686                 $moduleStyles[] = 'user.cssprefs';
3687
3688                 foreach ( $moduleStyles as $name ) {
3689                         $module = $resourceLoader->getModule( $name );
3690                         if ( !$module ) {
3691                                 continue;
3692                         }
3693                         if ( $name === 'site' ) {
3694                                 // HACK: The site module shouldn't be fragmented with a cache group and
3695                                 // http request. But in order to ensure its styles are separated and after the
3696                                 // ResourceLoaderDynamicStyles marker, pretend it is in a group called 'site'.
3697                                 // The scripts remain ungrouped and rides the bottom queue.
3698                                 $styles['site'][] = $name;
3699                                 continue;
3700                         }
3701                         $group = $module->getGroup();
3702                         // Modules in groups other than the ones needing special treatment
3703                         // (see $styles assignment)
3704                         // will be placed in the "other" style category.
3705                         $styles[isset( $styles[$group] ) ? $group : 'other'][] = $name;
3706                 }
3707
3708                 // We want site, private and user styles to override dynamically added
3709                 // styles from modules, but we want dynamically added styles to override
3710                 // statically added styles from other modules. So the order has to be
3711                 // other, dynamic, site, private, user. Add statically added styles for
3712                 // other modules
3713                 $links[] = $this->makeResourceLoaderLink(
3714                         $styles['other'],
3715                         ResourceLoaderModule::TYPE_STYLES
3716                 );
3717                 // Add normal styles added through addStyle()/addInlineStyle() here
3718                 $links[] = implode( '', $this->buildCssLinksArray() ) . $this->mInlineStyles;
3719                 // Add marker tag to mark the place where the client-side
3720                 // loader should inject dynamic styles
3721                 // We use a <meta> tag with a made-up name for this because that's valid HTML
3722                 $links[] = Html::element(
3723                         'meta',
3724                         [ 'name' => 'ResourceLoaderDynamicStyles', 'content' => '' ]
3725                 );
3726
3727                 // Add site-specific and user-specific styles
3728                 // 'private' at present only contains user.options, so put that before 'user'
3729                 // Any future private modules will likely have a similar user-specific character
3730                 foreach ( [ 'site', 'noscript', 'private', 'user' ] as $group ) {
3731                         $links[] = $this->makeResourceLoaderLink( $styles[$group],
3732                                 ResourceLoaderModule::TYPE_STYLES
3733                         );
3734                 }
3735
3736                 // Add stuff in $otherTags (previewed user CSS if applicable)
3737                 return self::getHtmlFromLoaderLinks( $links ) . implode( '', $otherTags );
3738         }
3739
3740         /**
3741          * @return array
3742          */
3743         public function buildCssLinksArray() {
3744                 $links = [];
3745
3746                 // Add any extension CSS
3747                 foreach ( $this->mExtStyles as $url ) {
3748                         $this->addStyle( $url );
3749                 }
3750                 $this->mExtStyles = [];
3751
3752                 foreach ( $this->styles as $file => $options ) {
3753                         $link = $this->styleLink( $file, $options );
3754                         if ( $link ) {
3755                                 $links[$file] = $link;
3756                         }
3757                 }
3758                 return $links;
3759         }
3760
3761         /**
3762          * Generate \<link\> tags for stylesheets
3763          *
3764          * @param string $style URL to the file
3765          * @param array $options Option, can contain 'condition', 'dir', 'media' keys
3766          * @return string HTML fragment
3767          */
3768         protected function styleLink( $style, array $options ) {
3769                 if ( isset( $options['dir'] ) ) {
3770                         if ( $this->getLanguage()->getDir() != $options['dir'] ) {
3771                                 return '';
3772                         }
3773                 }
3774
3775                 if ( isset( $options['media'] ) ) {
3776                         $media = self::transformCssMedia( $options['media'] );
3777                         if ( is_null( $media ) ) {
3778                                 return '';
3779                         }
3780                 } else {
3781                         $media = 'all';
3782                 }
3783
3784                 if ( substr( $style, 0, 1 ) == '/' ||
3785                         substr( $style, 0, 5 ) == 'http:' ||
3786                         substr( $style, 0, 6 ) == 'https:' ) {
3787                         $url = $style;
3788                 } else {
3789                         $config = $this->getConfig();
3790                         $url = $config->get( 'StylePath' ) . '/' . $style . '?' .
3791                                 $config->get( 'StyleVersion' );
3792                 }
3793
3794                 $link = Html::linkedStyle( $url, $media );
3795
3796                 if ( isset( $options['condition'] ) ) {
3797                         $condition = htmlspecialchars( $options['condition'] );
3798                         $link = "<!--[if $condition]>$link<![endif]-->";
3799                 }
3800                 return $link;
3801         }
3802
3803         /**
3804          * Transform path to web-accessible static resource.
3805          *
3806          * This is used to add a validation hash as query string.
3807          * This aids various behaviors:
3808          *
3809          * - Put long Cache-Control max-age headers on responses for improved
3810          *   cache performance.
3811          * - Get the correct version of a file as expected by the current page.
3812          * - Instantly get the updated version of a file after deployment.
3813          *
3814          * Avoid using this for urls included in HTML as otherwise clients may get different
3815          * versions of a resource when navigating the site depending on when the page was cached.
3816          * If changes to the url propagate, this is not a problem (e.g. if the url is in
3817          * an external stylesheet).
3818          *
3819          * @since 1.27
3820          * @param Config $config
3821          * @param string $path Path-absolute URL to file (from document root, must start with "/")
3822          * @return string URL
3823          */
3824         public static function transformResourcePath( Config $config, $path ) {
3825                 global $IP;
3826                 $remotePathPrefix = $config->get( 'ResourceBasePath' );
3827                 if ( $remotePathPrefix === '' ) {
3828                         // The configured base path is required to be empty string for
3829                         // wikis in the domain root
3830                         $remotePath = '/';
3831                 } else {
3832                         $remotePath = $remotePathPrefix;
3833                 }
3834                 if ( strpos( $path, $remotePath ) !== 0 ) {
3835                         // Path is outside wgResourceBasePath, ignore.
3836                         return $path;
3837                 }
3838                 $path = RelPath\getRelativePath( $path, $remotePath );
3839                 return self::transformFilePath( $remotePathPrefix, $IP, $path );
3840         }
3841
3842         /**
3843          * Utility method for transformResourceFilePath().
3844          *
3845          * Caller is responsible for ensuring the file exists. Emits a PHP warning otherwise.
3846          *
3847          * @since 1.27
3848          * @param string $remotePath URL path prefix that points to $localPath
3849          * @param string $localPath File directory exposed at $remotePath
3850          * @param string $file Path to target file relative to $localPath
3851          * @return string URL
3852          */
3853         public static function transformFilePath( $remotePathPrefix, $localPath, $file ) {
3854                 $hash = md5_file( "$localPath/$file" );
3855                 if ( $hash === false ) {
3856                         wfLogWarning( __METHOD__ . ": Failed to hash $localPath/$file" );
3857                         $hash = '';
3858                 }
3859                 return "$remotePathPrefix/$file?" . substr( $hash, 0, 5 );
3860         }
3861
3862         /**
3863          * Transform "media" attribute based on request parameters
3864          *
3865          * @param string $media Current value of the "media" attribute
3866          * @return string Modified value of the "media" attribute, or null to skip
3867          * this stylesheet
3868          */
3869         public static function transformCssMedia( $media ) {
3870                 global $wgRequest;
3871
3872                 // http://www.w3.org/TR/css3-mediaqueries/#syntax
3873                 $screenMediaQueryRegex = '/^(?:only\s+)?screen\b/i';
3874
3875                 // Switch in on-screen display for media testing
3876                 $switches = [
3877                         'printable' => 'print',
3878                         'handheld' => 'handheld',
3879                 ];
3880                 foreach ( $switches as $switch => $targetMedia ) {
3881                         if ( $wgRequest->getBool( $switch ) ) {
3882                                 if ( $media == $targetMedia ) {
3883                                         $media = '';
3884                                 } elseif ( preg_match( $screenMediaQueryRegex, $media ) === 1 ) {
3885                                         /* This regex will not attempt to understand a comma-separated media_query_list
3886                                          *
3887                                          * Example supported values for $media:
3888                                          * 'screen', 'only screen', 'screen and (min-width: 982px)' ),
3889                                          * Example NOT supported value for $media:
3890                                          * '3d-glasses, screen, print and resolution > 90dpi'
3891                                          *
3892                                          * If it's a print request, we never want any kind of screen stylesheets
3893                                          * If it's a handheld request (currently the only other choice with a switch),
3894                                          * we don't want simple 'screen' but we might want screen queries that
3895                                          * have a max-width or something, so we'll pass all others on and let the
3896                                          * client do the query.
3897                                          */
3898                                         if ( $targetMedia == 'print' || $media == 'screen' ) {
3899                                                 return null;
3900                                         }
3901                                 }
3902                         }
3903                 }
3904
3905                 return $media;
3906         }
3907
3908         /**
3909          * Add a wikitext-formatted message to the output.
3910          * This is equivalent to:
3911          *
3912          *    $wgOut->addWikiText( wfMessage( ... )->plain() )
3913          */
3914         public function addWikiMsg( /*...*/ ) {
3915                 $args = func_get_args();
3916                 $name = array_shift( $args );
3917                 $this->addWikiMsgArray( $name, $args );
3918         }
3919
3920         /**
3921          * Add a wikitext-formatted message to the output.
3922          * Like addWikiMsg() except the parameters are taken as an array
3923          * instead of a variable argument list.
3924          *
3925          * @param string $name
3926          * @param array $args
3927          */
3928         public function addWikiMsgArray( $name, $args ) {
3929                 $this->addHTML( $this->msg( $name, $args )->parseAsBlock() );
3930         }
3931
3932         /**
3933          * This function takes a number of message/argument specifications, wraps them in
3934          * some overall structure, and then parses the result and adds it to the output.
3935          *
3936          * In the $wrap, $1 is replaced with the first message, $2 with the second,
3937          * and so on. The subsequent arguments may be either
3938          * 1) strings, in which case they are message names, or
3939          * 2) arrays, in which case, within each array, the first element is the message
3940          *    name, and subsequent elements are the parameters to that message.
3941          *
3942          * Don't use this for messages that are not in the user's interface language.
3943          *
3944          * For example:
3945          *
3946          *    $wgOut->wrapWikiMsg( "<div class='error'>\n$1\n</div>", 'some-error' );
3947          *
3948          * Is equivalent to:
3949          *
3950          *    $wgOut->addWikiText( "<div class='error'>\n"
3951          *        . wfMessage( 'some-error' )->plain() . "\n</div>" );
3952          *
3953          * The newline after the opening div is needed in some wikitext. See bug 19226.
3954          *
3955          * @param string $wrap
3956          */
3957         public function wrapWikiMsg( $wrap /*, ...*/ ) {
3958                 $msgSpecs = func_get_args();
3959                 array_shift( $msgSpecs );
3960                 $msgSpecs = array_values( $msgSpecs );
3961                 $s = $wrap;
3962                 foreach ( $msgSpecs as $n => $spec ) {
3963                         if ( is_array( $spec ) ) {
3964                                 $args = $spec;
3965                                 $name = array_shift( $args );
3966                                 if ( isset( $args['options'] ) ) {
3967                                         unset( $args['options'] );
3968                                         wfDeprecated(
3969                                                 'Adding "options" to ' . __METHOD__ . ' is no longer supported',
3970                                                 '1.20'
3971                                         );
3972                                 }
3973                         } else {
3974                                 $args = [];
3975                                 $name = $spec;
3976                         }
3977                         $s = str_replace( '$' . ( $n + 1 ), $this->msg( $name, $args )->plain(), $s );
3978                 }
3979                 $this->addWikiText( $s );
3980         }
3981
3982         /**
3983          * Enables/disables TOC, doesn't override __NOTOC__
3984          * @param bool $flag
3985          * @since 1.22
3986          */
3987         public function enableTOC( $flag = true ) {
3988                 $this->mEnableTOC = $flag;
3989         }
3990
3991         /**
3992          * @return bool
3993          * @since 1.22
3994          */
3995         public function isTOCEnabled() {
3996                 return $this->mEnableTOC;
3997         }
3998
3999         /**
4000          * Enables/disables section edit links, doesn't override __NOEDITSECTION__
4001          * @param bool $flag
4002          * @since 1.23
4003          */
4004         public function enableSectionEditLinks( $flag = true ) {
4005                 $this->mEnableSectionEditLinks = $flag;
4006         }
4007
4008         /**
4009          * @return bool
4010          * @since 1.23
4011          */
4012         public function sectionEditLinksEnabled() {
4013                 return $this->mEnableSectionEditLinks;
4014         }
4015
4016         /**
4017          * Helper function to setup the PHP implementation of OOUI to use in this request.
4018          *
4019          * @since 1.26
4020          * @param String $skinName The Skin name to determine the correct OOUI theme
4021          * @param String $dir Language direction
4022          */
4023         public static function setupOOUI( $skinName = '', $dir = 'ltr' ) {
4024                 $themes = ExtensionRegistry::getInstance()->getAttribute( 'SkinOOUIThemes' );
4025                 // Make keys (skin names) lowercase for case-insensitive matching.
4026                 $themes = array_change_key_case( $themes, CASE_LOWER );
4027                 $theme = isset( $themes[$skinName] ) ? $themes[$skinName] : 'MediaWiki';
4028                 // For example, 'OOUI\MediaWikiTheme'.
4029                 $themeClass = "OOUI\\{$theme}Theme";
4030                 OOUI\Theme::setSingleton( new $themeClass() );
4031                 OOUI\Element::setDefaultDir( $dir );
4032         }
4033
4034         /**
4035          * Add ResourceLoader module styles for OOUI and set up the PHP implementation of it for use with
4036          * MediaWiki and this OutputPage instance.
4037          *
4038          * @since 1.25
4039          */
4040         public function enableOOUI() {
4041                 self::setupOOUI(
4042                         strtolower( $this->getSkin()->getSkinName() ),
4043                         $this->getLanguage()->getDir()
4044                 );
4045                 $this->addModuleStyles( [
4046                         'oojs-ui-core.styles',
4047                         'oojs-ui.styles.icons',
4048                         'oojs-ui.styles.indicators',
4049                         'oojs-ui.styles.textures',
4050                         'mediawiki.widgets.styles',
4051                 ] );
4052                 // Used by 'skipFunction' of the four 'oojs-ui.styles.*' modules. Please don't treat this as a
4053                 // public API or you'll be severely disappointed when T87871 is fixed and it disappears.
4054                 $this->addMeta( 'X-OOUI-PHP', '1' );
4055         }
4056 }