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[mediawiki.git] / includes / parser / Parser.php

<?php
/**
 * PHP parser that converts wiki markup to HTML.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup Parser
 */

use MediaWiki\Cache\CacheKeyHelper;
use MediaWiki\Category\TrackingCategories;
use MediaWiki\Config\ServiceOptions;
use MediaWiki\HookContainer\HookContainer;
use MediaWiki\HookContainer\HookRunner;
use MediaWiki\Http\HttpRequestFactory;
use MediaWiki\Language\RawMessage;
use MediaWiki\Languages\LanguageConverterFactory;
use MediaWiki\Languages\LanguageNameUtils;
use MediaWiki\Linker\Linker;
use MediaWiki\Linker\LinkRenderer;
use MediaWiki\Linker\LinkRendererFactory;
use MediaWiki\Linker\LinkTarget;
use MediaWiki\MainConfigNames;
use MediaWiki\MediaWikiServices;
use MediaWiki\Output\OutputPage;
use MediaWiki\Page\File\BadFileLookup;
use MediaWiki\Page\PageIdentity;
use MediaWiki\Page\PageReference;
use MediaWiki\Parser\MagicWordArray;
use MediaWiki\Parser\MagicWordFactory;
use MediaWiki\Parser\ParserOutputFlags;
use MediaWiki\Parser\Sanitizer;
use MediaWiki\Preferences\SignatureValidatorFactory;
use MediaWiki\Request\FauxRequest;
use MediaWiki\Revision\RevisionAccessException;
use MediaWiki\Revision\RevisionRecord;
use MediaWiki\Revision\SlotRecord;
use MediaWiki\SpecialPage\SpecialPage;
use MediaWiki\SpecialPage\SpecialPageFactory;
use MediaWiki\Tidy\TidyDriverBase;
use MediaWiki\Title\MalformedTitleException;
use MediaWiki\Title\MediaWikiTitleCodec;
use MediaWiki\Title\NamespaceInfo;
use MediaWiki\Title\Title;
use MediaWiki\Title\TitleFormatter;
use MediaWiki\User\User;
use MediaWiki\User\UserFactory;
use MediaWiki\User\UserIdentity;
use MediaWiki\User\UserNameUtils;
use MediaWiki\User\UserOptionsLookup;
use MediaWiki\Utils\MWTimestamp;
use MediaWiki\Utils\UrlUtils;
use Psr\Log\LoggerInterface;
use Wikimedia\Bcp47Code\Bcp47CodeValue;
use Wikimedia\IPUtils;
use Wikimedia\Parsoid\Core\SectionMetadata;
use Wikimedia\Parsoid\Core\TOCData;
use Wikimedia\ScopedCallback;

/**
 * @defgroup Parser Parser
 */

/**
 * PHP Parser - Processes wiki markup (which uses a more user-friendly
 * syntax, such as "[[link]]" for making links), and provides a one-way
 * transformation of that wiki markup it into (X)HTML output / markup
 * (which in turn the browser understands, and can display).
 *
 * There are seven main entry points into the Parser class:
 *
 * - Parser::parse()
 *     produces HTML output
 * - Parser::preSaveTransform()
 *     produces altered wiki markup
 * - Parser::preprocess()
 *     removes HTML comments and expands templates
 * - Parser::cleanSig() and Parser::cleanSigInSig()
 *     cleans a signature before saving it to preferences
 * - Parser::getSection()
 *     return the content of a section from an article for section editing
 * - Parser::replaceSection()
 *     replaces a section by number inside an article
 * - Parser::getPreloadText()
 *     removes <noinclude> sections and <includeonly> tags
 *
 * @warning $wgUser or $wgTitle or $wgRequest or $wgLang. Keep them away!
 *
 * @par Settings:
 * $wgNamespacesWithSubpages
 *
 * @par Settings only within ParserOptions:
 * $wgAllowExternalImages
 * $wgAllowSpecialInclusion
 * $wgInterwikiMagic
 * $wgMaxArticleSize
 *
 * @ingroup Parser
 */
#[AllowDynamicProperties]
class Parser {

        # Flags for Parser::setFunctionHook
        public const SFH_NO_HASH = 1;
        public const SFH_OBJECT_ARGS = 2;

        # Constants needed for external link processing
        /**
         * Everything except bracket, space, or control characters.
         * \p{Zs} is unicode 'separator, space' category. It covers the space 0x20
         * as well as U+3000 is IDEOGRAPHIC SPACE for T21052.
         * \x{FFFD} is the Unicode replacement character, which the HTML5 spec
         * uses to replace invalid HTML characters.
         */
        public const EXT_LINK_URL_CLASS = '[^][<>"\\x00-\\x20\\x7F\p{Zs}\x{FFFD}]';
        /**
         * Simplified expression to match an IPv4 or IPv6 address, or
         * at least one character of a host name (embeds Parser::EXT_LINK_URL_CLASS)
         */
        // phpcs:ignore Generic.Files.LineLength
        private const EXT_LINK_ADDR = '(?:[0-9.]+|\\[(?i:[0-9a-f:.]+)\\]|[^][<>"\\x00-\\x20\\x7F\p{Zs}\x{FFFD}])';
        /** RegExp to make image URLs (embeds IPv6 part of Parser::EXT_LINK_ADDR) */
        // phpcs:ignore Generic.Files.LineLength
        private const EXT_IMAGE_REGEX = '/^(http:\/\/|https:\/\/)((?:\\[(?i:[0-9a-f:.]+)\\])?[^][<>"\\x00-\\x20\\x7F\p{Zs}\x{FFFD}]+)
                \\/([A-Za-z0-9_.,~%\\-+&;#*?!=()@\\x80-\\xFF]+)\\.((?i)gif|png|jpg|jpeg)$/Sxu';

        /** Regular expression for a non-newline space */
        private const SPACE_NOT_NL = '(?:\t|&nbsp;|&\#0*160;|&\#[Xx]0*[Aa]0;|\p{Zs})';

        /**
         * @var int Preprocess wikitext in transclusion mode
         * @deprecated Since 1.36
         */
        public const PTD_FOR_INCLUSION = Preprocessor::DOM_FOR_INCLUSION;

        # Allowed values for $this->mOutputType
        /** Output type: like Parser::parse() */
        public const OT_HTML = 1;
        /** Output type: like Parser::preSaveTransform() */
        public const OT_WIKI = 2;
        /** Output type: like Parser::preprocess() */
        public const OT_PREPROCESS = 3;
        /**
         * Output type: like Parser::extractSections() - portions of the
         * original are returned unchanged.
         */
        public const OT_PLAIN = 4;

        /**
         * @var string Prefix and suffix for temporary replacement strings
         * for the multipass parser.
         *
         * \x7f should never appear in input as it's disallowed in XML.
         * Using it at the front also gives us a little extra robustness
         * since it shouldn't match when butted up against identifier-like
         * string constructs.
         *
         * Must not consist of all title characters, or else it will change
         * the behavior of <nowiki> in a link.
         *
         * Must have a character that needs escaping in attributes, otherwise
         * someone could put a strip marker in an attribute, to get around
         * escaping quote marks, and break out of the attribute. Thus we add
         * `'".
         */
        public const MARKER_SUFFIX = "-QINU`\"'\x7f";
        public const MARKER_PREFIX = "\x7f'\"`UNIQ-";

        /**
         * Internal marker used by parser to track where the table of
         * contents should be. Various magic words can change the position
         * during the parse.  The table of contents is generated during
         * the parse, however skins have the final decision on whether the
         * table of contents is injected.  This placeholder element
         * identifies where in the page the table of contents should be
         * injected, if at all.
         * @var string
         * @see Keep this in sync with BlockLevelPass::execute() and
         *  RemexCompatMunger::isTableOfContentsMarker()
         * @internal Skins should *not* directly reference TOC_PLACEHOLDER
         * but instead use Parser::replaceTableOfContentsMarker().
         */
        public const TOC_PLACEHOLDER = '<meta property="mw:PageProp/toc" />';

        /**
         * Permissive regexp matching TOC_PLACEHOLDER.  This allows for some
         * minor modifications to the placeholder to be made by extensions
         * without breaking the TOC (T317857); note also that Parsoid's version
         * of the placeholder might include additional attributes.
         * @var string
         */
        private const TOC_PLACEHOLDER_REGEX = '/<meta\\b[^>]*\\bproperty\\s*=\\s*"mw:PageProp\\/toc"[^>]*\\/>/';

        # Persistent:
        /** @var array<string,callable> */
        private array $mTagHooks = [];
        /** @var array<string,array{0:callable,1:int}> */
        private array $mFunctionHooks = [];
        /** @var array<int,array<string,string>> */
        private array $mFunctionSynonyms = [ 0 => [], 1 => [] ];
        /** @var string[] */
        private array $mStripList = [];
        /** @var array<string,string> */
        private array $mVarCache = [];
        /** @var array<string,array<string,string[]>> */
        private array $mImageParams = [];
        /** @var array<string,MagicWordArray> */
        private array $mImageParamsMagicArray = [];
        /** @deprecated since 1.35 */
        public $mMarkerIndex = 0;

        # Initialised by initializeVariables()
        private MagicWordArray $mVariables;
        private MagicWordArray $mSubstWords;

        # Initialised in constructor
        private string $mExtLinkBracketedRegex;
        private UrlUtils $urlUtils;
        private Preprocessor $mPreprocessor;

        # Cleared with clearState():
        private ParserOutput $mOutput;
        private int $mAutonumber = 0;
        private StripState $mStripState;
        private LinkHolderArray $mLinkHolders;
        private int $mLinkID = 0;
        private array $mIncludeSizes;
        /** @deprecated since 1.35 */
        public $mPPNodeCount;
        /** @deprecated since 1.35 */
        public $mHighestExpansionDepth;
        private array $mTplRedirCache;
        /** @internal */
        public array $mHeadings;
        /** @var array<string,string> */
        private array $mDoubleUnderscores;
        /**
         * Number of expensive parser function calls
         * @deprecated since 1.35
         */
        public $mExpensiveFunctionCount;
        private bool $mShowToc;
        private bool $mForceTocPosition;
        private array $mTplDomCache;
        private ?UserIdentity $mUser;

        # Temporary
        # These are variables reset at least once per parse regardless of $clearState

        /**
         * @var ParserOptions|null
         * @deprecated since 1.35, use Parser::getOptions()
         */
        public $mOptions;

        /**
         * Title context, used for self-link rendering and similar things
         *
         * @deprecated since 1.35, use Parser::getPage()
         */
        public Title $mTitle;
        /** Output type, one of the OT_xxx constants */
        private int $mOutputType;
        /**
         * Shortcut alias, see Parser::setOutputType()
         * @deprecated since 1.35
         */
        public $ot;
        /** ID to display in {{REVISIONID}} tags */
        private ?int $mRevisionId = null;
        /** The timestamp of the specified revision ID */
        private ?string $mRevisionTimestamp = null;
        /** User to display in {{REVISIONUSER}} tag */
        private ?string $mRevisionUser = null;
        /** Size to display in {{REVISIONSIZE}} variable */
        private ?int $mRevisionSize = null;
        /** @var int|false For {{PAGESIZE}} on current page */
        private $mInputSize = false;

        private ?RevisionRecord $mRevisionRecordObject = null;

        /**
         * Array with the language name of each language link (i.e. the
         * interwiki prefix) in the key, value arbitrary. Used to avoid sending
         * duplicate language links to the ParserOutput.
         */
        private array $mLangLinkLanguages;

        /**
         * A cache of the current revisions of titles. Keys are $title->getPrefixedDbKey()
         *
         * @since 1.24
         */
        private ?MapCacheLRU $currentRevisionCache = null;

        /**
         * @var bool|string Recursive call protection.
         * @internal
         */
        private $mInParse = false;

        private SectionProfiler $mProfiler;
        private ?LinkRenderer $mLinkRenderer = null;

        private MagicWordFactory $magicWordFactory;
        private Language $contLang;
        private LanguageConverterFactory $languageConverterFactory;
        private ParserFactory $factory;
        private SpecialPageFactory $specialPageFactory;
        private TitleFormatter $titleFormatter;
        /**
         * This is called $svcOptions instead of $options like elsewhere to avoid confusion with
         * $mOptions, which is public and widely used, and also with the local variable $options used
         * for ParserOptions throughout this file.
         */
        private ServiceOptions $svcOptions;
        private LinkRendererFactory $linkRendererFactory;
        private NamespaceInfo $nsInfo;
        private LoggerInterface $logger;
        private BadFileLookup $badFileLookup;
        private HookContainer $hookContainer;
        private HookRunner $hookRunner;
        private TidyDriverBase $tidy;
        private WANObjectCache $wanCache;
        private UserOptionsLookup $userOptionsLookup;
        private UserFactory $userFactory;
        private HttpRequestFactory $httpRequestFactory;
        private TrackingCategories $trackingCategories;
        private SignatureValidatorFactory $signatureValidatorFactory;
        private UserNameUtils $userNameUtils;

        /**
         * @internal For use by ServiceWiring
         */
        public const CONSTRUCTOR_OPTIONS = [
                // See documentation for the corresponding config options
                // Many of these are only used in (eg) CoreMagicVariables
                MainConfigNames::AllowDisplayTitle,
                MainConfigNames::AllowSlowParserFunctions,
                MainConfigNames::ArticlePath,
                MainConfigNames::EnableScaryTranscluding,
                MainConfigNames::ExtraInterlanguageLinkPrefixes,
                MainConfigNames::FragmentMode,
                MainConfigNames::Localtimezone,
                MainConfigNames::MaxSigChars,
                MainConfigNames::MaxTocLevel,
                MainConfigNames::MiserMode,
                MainConfigNames::RawHtml,
                MainConfigNames::ScriptPath,
                MainConfigNames::Server,
                MainConfigNames::ServerName,
                MainConfigNames::ShowHostnames,
                MainConfigNames::SignatureValidation,
                MainConfigNames::Sitename,
                MainConfigNames::StylePath,
                MainConfigNames::TranscludeCacheExpiry,
                MainConfigNames::PreprocessorCacheThreshold,
                MainConfigNames::ParserEnableLegacyMediaDOM,
                MainConfigNames::EnableParserLimitReporting,
        ];

        /**
         * Constructing parsers directly is not allowed! Use a ParserFactory.
         * @internal
         *
         * @param ServiceOptions $svcOptions
         * @param MagicWordFactory $magicWordFactory
         * @param Language $contLang Content language
         * @param ParserFactory $factory
         * @param UrlUtils $urlUtils
         * @param SpecialPageFactory $spFactory
         * @param LinkRendererFactory $linkRendererFactory
         * @param NamespaceInfo $nsInfo
         * @param LoggerInterface $logger
         * @param BadFileLookup $badFileLookup
         * @param LanguageConverterFactory $languageConverterFactory
         * @param HookContainer $hookContainer
         * @param TidyDriverBase $tidy
         * @param WANObjectCache $wanCache
         * @param UserOptionsLookup $userOptionsLookup
         * @param UserFactory $userFactory
         * @param TitleFormatter $titleFormatter
         * @param HttpRequestFactory $httpRequestFactory
         * @param TrackingCategories $trackingCategories
         * @param SignatureValidatorFactory $signatureValidatorFactory
         * @param UserNameUtils $userNameUtils
         */
        public function __construct(
                ServiceOptions $svcOptions,
                MagicWordFactory $magicWordFactory,
                Language $contLang,
                ParserFactory $factory,
                UrlUtils $urlUtils,
                SpecialPageFactory $spFactory,
                LinkRendererFactory $linkRendererFactory,
                NamespaceInfo $nsInfo,
                LoggerInterface $logger,
                BadFileLookup $badFileLookup,
                LanguageConverterFactory $languageConverterFactory,
                HookContainer $hookContainer,
                TidyDriverBase $tidy,
                WANObjectCache $wanCache,
                UserOptionsLookup $userOptionsLookup,
                UserFactory $userFactory,
                TitleFormatter $titleFormatter,
                HttpRequestFactory $httpRequestFactory,
                TrackingCategories $trackingCategories,
                SignatureValidatorFactory $signatureValidatorFactory,
                UserNameUtils $userNameUtils
        ) {
                if ( ParserFactory::$inParserFactory === 0 ) {
                        // Direct construction of Parser was deprecated in 1.34 and
                        // removed in 1.36; use a ParserFactory instead.
                        throw new BadMethodCallException( 'Direct construction of Parser not allowed' );
                }
                $svcOptions->assertRequiredOptions( self::CONSTRUCTOR_OPTIONS );
                $this->svcOptions = $svcOptions;

                $this->urlUtils = $urlUtils;
                $this->mExtLinkBracketedRegex = '/\[(((?i)' . $this->urlUtils->validProtocols() . ')' .
                        self::EXT_LINK_ADDR .
                        self::EXT_LINK_URL_CLASS . '*)\p{Zs}*([^\]\\x00-\\x08\\x0a-\\x1F\\x{FFFD}]*)\]/Su';

                $this->magicWordFactory = $magicWordFactory;

                $this->contLang = $contLang;

                $this->factory = $factory;
                $this->specialPageFactory = $spFactory;
                $this->linkRendererFactory = $linkRendererFactory;
                $this->nsInfo = $nsInfo;
                $this->logger = $logger;
                $this->badFileLookup = $badFileLookup;

                $this->languageConverterFactory = $languageConverterFactory;

                $this->hookContainer = $hookContainer;
                $this->hookRunner = new HookRunner( $hookContainer );

                $this->tidy = $tidy;

                $this->wanCache = $wanCache;
                $this->mPreprocessor = new Preprocessor_Hash(
                        $this,
                        $this->wanCache,
                        [
                                'cacheThreshold' => $svcOptions->get( MainConfigNames::PreprocessorCacheThreshold ),
                                'disableLangConversion' => $languageConverterFactory->isConversionDisabled(),
                        ]
                );

                $this->userOptionsLookup = $userOptionsLookup;
                $this->userFactory = $userFactory;
                $this->titleFormatter = $titleFormatter;
                $this->httpRequestFactory = $httpRequestFactory;
                $this->trackingCategories = $trackingCategories;
                $this->signatureValidatorFactory = $signatureValidatorFactory;
                $this->userNameUtils = $userNameUtils;

                // These steps used to be done in "::firstCallInit()"
                // (if you're chasing a reference from some old code)
                CoreParserFunctions::register(
                        $this,
                        new ServiceOptions( CoreParserFunctions::REGISTER_OPTIONS, $svcOptions )
                );
                CoreTagHooks::register(
                        $this,
                        new ServiceOptions( CoreTagHooks::REGISTER_OPTIONS, $svcOptions )
                );
                $this->initializeVariables();

                $this->hookRunner->onParserFirstCallInit( $this );
                $this->mTitle = Title::makeTitle( NS_SPECIAL, 'Badtitle/Missing' );
        }

        /**
         * Reduce memory usage to reduce the impact of circular references
         */
        public function __destruct() {
                // @phan-suppress-next-line PhanRedundantCondition Typed property not set in constructor, may be uninitialized
                if ( isset( $this->mLinkHolders ) ) {
                        // @phan-suppress-next-line PhanTypeObjectUnsetDeclaredProperty
                        unset( $this->mLinkHolders );
                }
                // @phan-suppress-next-line PhanTypeSuspiciousNonTraversableForeach
                foreach ( $this as $name => $value ) {
                        unset( $this->$name );
                }
        }

        /**
         * Allow extensions to clean up when the parser is cloned
         */
        public function __clone() {
                $this->mInParse = false;

                // T58226: When you create a reference "to" an object field, that
                // makes the object field itself be a reference too (until the other
                // reference goes out of scope). When cloning, any field that's a
                // reference is copied as a reference in the new object. Both of these
                // are defined PHP5 behaviors, as inconvenient as it is for us when old
                // hooks from PHP4 days are passing fields by reference.
                foreach ( [ 'mStripState', 'mVarCache' ] as $k ) {
                        // Make a non-reference copy of the field, then rebind the field to
                        // reference the new copy.
                        $tmp = $this->$k;
                        $this->$k =& $tmp;
                        unset( $tmp );
                }

                $this->mPreprocessor = clone $this->mPreprocessor;
                $this->mPreprocessor->resetParser( $this );

                $this->hookRunner->onParserCloned( $this );
        }

        /**
         * Used to do various kinds of initialisation on the first call of the
         * parser.
         * @deprecated since 1.35, this initialization is done in the constructor
         *  and manual calls to ::firstCallInit() have no effect.
         * @since 1.7
         */
        public function firstCallInit() {
                /*
                 * This method should be hard-deprecated once remaining calls are
                 * removed; it no longer does anything.
                 */
        }

        /**
         * Clear Parser state
         *
         * @internal
         */
        public function clearState() {
                $this->resetOutput();
                $this->mAutonumber = 0;
                $this->mLinkHolders = new LinkHolderArray(
                        $this,
                        $this->getContentLanguageConverter(),
                        $this->getHookContainer()
                );
                $this->mLinkID = 0;
                $this->mRevisionTimestamp = null;
                $this->mRevisionId = null;
                $this->mRevisionUser = null;
                $this->mRevisionSize = null;
                $this->mRevisionRecordObject = null;
                $this->mVarCache = [];
                $this->mUser = null;
                $this->mLangLinkLanguages = [];
                $this->currentRevisionCache = null;

                $this->mStripState = new StripState( $this );

                # Clear these on every parse, T6549
                $this->mTplRedirCache = [];
                $this->mTplDomCache = [];

                $this->mShowToc = true;
                $this->mForceTocPosition = false;
                $this->mIncludeSizes = [
                        'post-expand' => 0,
                        'arg' => 0,
                ];
                $this->mPPNodeCount = 0;
                $this->mHighestExpansionDepth = 0;
                $this->mHeadings = [];
                $this->mDoubleUnderscores = [];
                $this->mExpensiveFunctionCount = 0;

                $this->mProfiler = new SectionProfiler();

                $this->hookRunner->onParserClearState( $this );
        }

        /**
         * Reset the ParserOutput
         * @since 1.34
         */
        public function resetOutput() {
                $this->mOutput = new ParserOutput;
                $this->mOptions->registerWatcher( [ $this->mOutput, 'recordOption' ] );
        }

        /**
         * Convert wikitext to HTML
         * Do not call this function recursively.
         *
         * @param string $text Text we want to parse
         * @param-taint $text escapes_htmlnoent
         * @param PageReference $page
         * @param ParserOptions $options
         * @param bool $linestart
         * @param bool $clearState
         * @param int|null $revid ID of the revision being rendered. This is used to render
         *  REVISION* magic words. 0 means that any current revision will be used. Null means
         *  that {{REVISIONID}}/{{REVISIONUSER}} will be empty and {{REVISIONTIMESTAMP}} will
         *  use the current timestamp.
         * @return ParserOutput
         * @return-taint escaped
         * @since 1.10 method is public
         */
        public function parse(
                $text, PageReference $page, ParserOptions $options,
                $linestart = true, $clearState = true, $revid = null
        ) {
                if ( $clearState ) {
                        // We use U+007F DELETE to construct strip markers, so we have to make
                        // sure that this character does not occur in the input text.
                        $text = strtr( $text, "\x7f", "?" );
                        $magicScopeVariable = $this->lock();
                }
                // Strip U+0000 NULL (T159174)
                $text = str_replace( "\000", '', $text );

                $this->startParse( $page, $options, self::OT_HTML, $clearState );

                $this->currentRevisionCache = null;
                $this->mInputSize = strlen( $text );
                $this->mOutput->resetParseStartTime();

                $oldRevisionId = $this->mRevisionId;
                $oldRevisionRecordObject = $this->mRevisionRecordObject;
                $oldRevisionTimestamp = $this->mRevisionTimestamp;
                $oldRevisionUser = $this->mRevisionUser;
                $oldRevisionSize = $this->mRevisionSize;
                if ( $revid !== null ) {
                        $this->mRevisionId = $revid;
                        $this->mRevisionRecordObject = null;
                        $this->mRevisionTimestamp = null;
                        $this->mRevisionUser = null;
                        $this->mRevisionSize = null;
                }

                $text = $this->internalParse( $text );
                $this->hookRunner->onParserAfterParse( $this, $text, $this->mStripState );

                $text = $this->internalParseHalfParsed( $text, true, $linestart );

                /**
                 * A converted title will be provided in the output object if title and
                 * content conversion are enabled, the article text does not contain
                 * a conversion-suppressing double-underscore tag, and no
                 * {{DISPLAYTITLE:...}} is present. DISPLAYTITLE takes precedence over
                 * automatic link conversion.
                 */
                if ( !$options->getDisableTitleConversion()
                        && !isset( $this->mDoubleUnderscores['nocontentconvert'] )
                        && !isset( $this->mDoubleUnderscores['notitleconvert'] )
                        && $this->mOutput->getDisplayTitle() === false
                ) {
                        $titleText = $this->getTargetLanguageConverter()->getConvRuleTitle();
                        if ( $titleText !== false ) {
                                $titleText = Sanitizer::removeSomeTags( $titleText );
                        } else {
                                [ $nsText, $nsSeparator, $mainText ] = $this->getTargetLanguageConverter()->convertSplitTitle( $page );
                                // In the future, those three pieces could be stored separately rather than joined into $titleText,
                                // and OutputPage would format them and join them together, to resolve T314399.
                                $titleText = self::formatPageTitle( $nsText, $nsSeparator, $mainText );
                        }
                        $this->mOutput->setTitleText( $titleText );
                }

                # Compute runtime adaptive expiry if set
                $this->mOutput->finalizeAdaptiveCacheExpiry();

                # Warn if too many heavyweight parser functions were used
                if ( $this->mExpensiveFunctionCount > $this->mOptions->getExpensiveParserFunctionLimit() ) {
                        $this->limitationWarn( 'expensive-parserfunction',
                                $this->mExpensiveFunctionCount,
                                $this->mOptions->getExpensiveParserFunctionLimit()
                        );
                }

                # Information on limits, for the benefit of users who try to skirt them
                if ( $this->svcOptions->get( MainConfigNames::EnableParserLimitReporting ) ) {
                        $this->makeLimitReport();
                }

                # Wrap non-interface parser output in a <div> so it can be targeted
                # with CSS (T37247)
                $class = $this->mOptions->getWrapOutputClass();
                if ( $class !== false && !$this->mOptions->getInterfaceMessage() ) {
                        $this->mOutput->addWrapperDivClass( $class );
                }

                $this->mOutput->setText( $text );

                $this->mRevisionId = $oldRevisionId;
                $this->mRevisionRecordObject = $oldRevisionRecordObject;
                $this->mRevisionTimestamp = $oldRevisionTimestamp;
                $this->mRevisionUser = $oldRevisionUser;
                $this->mRevisionSize = $oldRevisionSize;
                $this->mInputSize = false;
                $this->currentRevisionCache = null;

                return $this->mOutput;
        }

        /**
         * Set the limit report data in the current ParserOutput.
         */
        protected function makeLimitReport() {
                $maxIncludeSize = $this->mOptions->getMaxIncludeSize();

                $cpuTime = $this->mOutput->getTimeSinceStart( 'cpu' );
                if ( $cpuTime !== null ) {
                        $this->mOutput->setLimitReportData( 'limitreport-cputime',
                                sprintf( "%.3f", $cpuTime )
                        );
                }

                $wallTime = $this->mOutput->getTimeSinceStart( 'wall' );
                $this->mOutput->setLimitReportData( 'limitreport-walltime',
                        sprintf( "%.3f", $wallTime )
                );

                $this->mOutput->setLimitReportData( 'limitreport-ppvisitednodes',
                        [ $this->mPPNodeCount, $this->mOptions->getMaxPPNodeCount() ]
                );
                $this->mOutput->setLimitReportData( 'limitreport-postexpandincludesize',
                        [ $this->mIncludeSizes['post-expand'], $maxIncludeSize ]
                );
                $this->mOutput->setLimitReportData( 'limitreport-templateargumentsize',
                        [ $this->mIncludeSizes['arg'], $maxIncludeSize ]
                );
                $this->mOutput->setLimitReportData( 'limitreport-expansiondepth',
                        [ $this->mHighestExpansionDepth, $this->mOptions->getMaxPPExpandDepth() ]
                );
                $this->mOutput->setLimitReportData( 'limitreport-expensivefunctioncount',
                        [ $this->mExpensiveFunctionCount, $this->mOptions->getExpensiveParserFunctionLimit() ]
                );

                foreach ( $this->mStripState->getLimitReport() as [ $key, $value ] ) {
                        $this->mOutput->setLimitReportData( $key, $value );
                }

                $this->hookRunner->onParserLimitReportPrepare( $this, $this->mOutput );

                // Add on template profiling data in human/machine readable way
                $dataByFunc = $this->mProfiler->getFunctionStats();
                uasort( $dataByFunc, static function ( $a, $b ) {
                        return $b['real'] <=> $a['real']; // descending order
                } );
                $profileReport = [];
                foreach ( array_slice( $dataByFunc, 0, 10 ) as $item ) {
                        $profileReport[] = sprintf( "%6.2f%% %8.3f %6d %s",
                                $item['%real'], $item['real'], $item['calls'],
                                htmlspecialchars( $item['name'] ) );
                }

                $this->mOutput->setLimitReportData( 'limitreport-timingprofile', $profileReport );

                // Add other cache related metadata
                if ( $this->svcOptions->get( MainConfigNames::ShowHostnames ) ) {
                        $this->mOutput->setLimitReportData( 'cachereport-origin', wfHostname() );
                }
                $this->mOutput->setLimitReportData( 'cachereport-timestamp',
                        $this->mOutput->getCacheTime() );
                $this->mOutput->setLimitReportData( 'cachereport-ttl',
                        $this->mOutput->getCacheExpiry() );
                $this->mOutput->setLimitReportData( 'cachereport-transientcontent',
                        $this->mOutput->hasReducedExpiry() );
        }

        /**
         * Half-parse wikitext to half-parsed HTML. This recursive parser entry point
         * can be called from an extension tag hook.
         *
         * The output of this function IS NOT SAFE PARSED HTML; it is "half-parsed"
         * instead, which means that lists and links have not been fully parsed yet,
         * and strip markers are still present.
         *
         * Use recursiveTagParseFully() to fully parse wikitext to output-safe HTML.
         *
         * Use this function if you're a parser tag hook and you want to parse
         * wikitext before or after applying additional transformations, and you
         * intend to *return the result as hook output*, which will cause it to go
         * through the rest of parsing process automatically.
         *
         * If $frame is not provided, then template variables (e.g., {{{1}}}) within
         * $text are not expanded
         *
         * @param string $text Text extension wants to have parsed
         * @param-taint $text escapes_htmlnoent
         * @param PPFrame|false $frame The frame to use for expanding any template variables
         * @return string UNSAFE half-parsed HTML
         * @return-taint escaped
         * @since 1.8
         */
        public function recursiveTagParse( $text, $frame = false ) {
                $text = $this->internalParse( $text, false, $frame );
                return $text;
        }

        /**
         * Fully parse wikitext to fully parsed HTML. This recursive parser entry
         * point can be called from an extension tag hook.
         *
         * The output of this function is fully-parsed HTML that is safe for output.
         * If you're a parser tag hook, you might want to use recursiveTagParse()
         * instead.
         *
         * If $frame is not provided, then template variables (e.g., {{{1}}}) within
         * $text are not expanded
         *
         * @since 1.25
         *
         * @param string $text Text extension wants to have parsed
         * @param-taint $text escapes_htmlnoent
         * @param PPFrame|false $frame The frame to use for expanding any template variables
         * @return string Fully parsed HTML
         * @return-taint escaped
         */
        public function recursiveTagParseFully( $text, $frame = false ) {
                $text = $this->recursiveTagParse( $text, $frame );
                $text = $this->internalParseHalfParsed( $text, false );
                return $text;
        }

        /**
         * Needed by Parsoid/PHP to ensure all the hooks for extensions
         * are run in the right order. The primary differences between this
         * and recursiveTagParseFully are:
         * (a) absence of $frame
         * (b) passing true to internalParseHalfParse so all hooks are run
         * (c) running 'ParserAfterParse' hook at the same point in the parsing
         *     pipeline when parse() does it. This kinda mimics Parsoid/JS behavior
         *     where exttags are processed by the M/w API.
         *
         * This is a temporary convenience method and will go away as we proceed
         * further with Parsoid <-> Parser.php integration.
         *
         * @internal
         * @deprecated
         * @param string $text Wikitext source of the extension
         * @return string
         * @return-taint escaped
         */
        public function parseExtensionTagAsTopLevelDoc( $text ) {
                $text = $this->recursiveTagParse( $text );
                $this->hookRunner->onParserAfterParse( $this, $text, $this->mStripState );
                $text = $this->internalParseHalfParsed( $text, true );
                return $text;
        }

        /**
         * Expand templates and variables in the text, producing valid, static wikitext.
         * Also removes comments.
         * Do not call this function recursively.
         * @param string $text
         * @param ?PageReference $page
         * @param ParserOptions $options
         * @param int|null $revid
         * @param PPFrame|false $frame
         * @return mixed|string
         * @since 1.8
         */
        public function preprocess(
                $text,
                ?PageReference $page,
                ParserOptions $options,
                $revid = null,
                $frame = false
        ) {
                $magicScopeVariable = $this->lock();
                $this->startParse( $page, $options, self::OT_PREPROCESS, true );
                if ( $revid !== null ) {
                        $this->mRevisionId = $revid;
                }
                $this->hookRunner->onParserBeforePreprocess( $this, $text, $this->mStripState );
                $text = $this->replaceVariables( $text, $frame );
                $text = $this->mStripState->unstripBoth( $text );
                return $text;
        }

        /**
         * Recursive parser entry point that can be called from an extension tag
         * hook.
         *
         * @param string $text Text to be expanded
         * @param PPFrame|false $frame The frame to use for expanding any template variables
         * @return string
         * @since 1.19
         */
        public function recursivePreprocess( $text, $frame = false ) {
                $text = $this->replaceVariables( $text, $frame );
                $text = $this->mStripState->unstripBoth( $text );
                return $text;
        }

        /**
         * Process the wikitext for the "?preload=" feature. (T7210)
         *
         * "<noinclude>", "<includeonly>" etc. are parsed as for template
         * transclusion, comments, templates, arguments, tags hooks and parser
         * functions are untouched.
         *
         * @param string $text
         * @param PageReference $page
         * @param ParserOptions $options
         * @param array $params
         * @return string
         * @since 1.17
         */
        public function getPreloadText( $text, PageReference $page, ParserOptions $options, $params = [] ) {
                $msg = new RawMessage( $text );
                $text = $msg->params( $params )->plain();

                # Parser (re)initialisation
                $magicScopeVariable = $this->lock();
                $this->startParse( $page, $options, self::OT_PLAIN, true );

                $flags = PPFrame::NO_ARGS | PPFrame::NO_TEMPLATES;
                $dom = $this->preprocessToDom( $text, Preprocessor::DOM_FOR_INCLUSION );
                $text = $this->getPreprocessor()->newFrame()->expand( $dom, $flags );
                $text = $this->mStripState->unstripBoth( $text );
                return $text;
        }

        /**
         * Set the current user.
         * Should only be used when doing pre-save transform.
         *
         * @param UserIdentity|null $user user identity or null (to reset)
         * @since 1.17
         */
        public function setUser( ?UserIdentity $user ) {
                $this->mUser = $user;
        }

        /**
         * Set the context title
         *
         * @deprecated since 1.37, use setPage() instead.
         * @param Title|null $t
         * @since 1.12
         */
        public function setTitle( Title $t = null ) {
                $this->setPage( $t );
        }

        /**
         * @since 1.6
         * @deprecated since 1.37, use getPage instead.
         * @return Title
         */
        public function getTitle(): Title {
                return $this->mTitle;
        }

        /**
         * Set the page used as context for parsing, e.g. when resolving relative subpage links.
         *
         * @since 1.37
         * @param ?PageReference $t
         */
        public function setPage( ?PageReference $t = null ) {
                if ( !$t ) {
                        $t = Title::makeTitle( NS_SPECIAL, 'Badtitle/Parser' );
                } else {
                        // For now (early 1.37 alpha), always convert to Title, so we don't have to do it over
                        // and over again in other methods. Eventually, we will no longer need to have a Title
                        // instance internally.
                        $t = Title::newFromPageReference( $t );
                }

                if ( $t->hasFragment() ) {
                        # Strip the fragment to avoid various odd effects
                        $this->mTitle = $t->createFragmentTarget( '' );
                } else {
                        $this->mTitle = $t;
                }
        }

        /**
         * Returns the page used as context for parsing, e.g. when resolving relative subpage links.
         * @since 1.37
         * @return ?PageReference Null if no page is set (deprecated since 1.34)
         */
        public function getPage(): ?PageReference {
                if ( $this->mTitle->isSpecial( 'Badtitle' ) ) {
                        [ , $subPage ] = $this->specialPageFactory->resolveAlias( $this->mTitle->getDBkey() );

                        if ( $subPage === 'Missing' ) {
                                wfDeprecated( __METHOD__ . ' without a Title set', '1.34' );
                                return null;
                        }
                }

                return $this->mTitle;
        }

        /**
         * Accessor for the output type.
         * @return int One of the Parser::OT_... constants
         * @since 1.35
         */
        public function getOutputType(): int {
                return $this->mOutputType;
        }

        /**
         * Mutator for the output type.
         * @param int $ot One of the Parser::OT_… constants
         * @since 1.8
         */
        public function setOutputType( $ot ): void {
                $this->mOutputType = $ot;
                # Shortcut alias
                $this->ot = [
                        'html' => $ot == self::OT_HTML,
                        'wiki' => $ot == self::OT_WIKI,
                        'pre' => $ot == self::OT_PREPROCESS,
                        'plain' => $ot == self::OT_PLAIN,
                ];
        }

        /**
         * Accessor/mutator for the output type
         *
         * @param int|null $x New value or null to just get the current one
         * @return int
         * @deprecated since 1.35, use getOutputType()/setOutputType()
         */
        public function OutputType( $x = null ) {
                wfDeprecated( __METHOD__, '1.35' );
                return wfSetVar( $this->mOutputType, $x );
        }

        /**
         * @return ParserOutput
         * @since 1.14
         */
        public function getOutput() {
                // @phan-suppress-next-line PhanRedundantCondition False positive, see https://github.com/phan/phan/issues/4720
                if ( !isset( $this->mOutput ) ) {
                        wfDeprecated( __METHOD__ . ' before initialization', '1.42' );
                        // @phan-suppress-next-line PhanTypeMismatchReturnProbablyReal We don’t want to tell anyone we’re doing this
                        return null;
                }
                return $this->mOutput;
        }

        /**
         * @return ParserOptions|null
         * @since 1.6
         */
        public function getOptions() {
                return $this->mOptions;
        }

        /**
         * Mutator for the ParserOptions object
         * @param ParserOptions $options The new parser options
         * @since 1.35
         */
        public function setOptions( ParserOptions $options ): void {
                $this->mOptions = $options;
        }

        /**
         * Accessor/mutator for the ParserOptions object
         *
         * @param ParserOptions|null $x New value or null to just get the current one
         * @return ParserOptions Current ParserOptions object
         * @deprecated since 1.35, use getOptions() / setOptions()
         */
        public function Options( $x = null ) {
                wfDeprecated( __METHOD__, '1.35' );
                return wfSetVar( $this->mOptions, $x );
        }

        /**
         * @return int
         * @since 1.14
         */
        public function nextLinkID() {
                return $this->mLinkID++;
        }

        /**
         * @param int $id
         * @since 1.8
         */
        public function setLinkID( $id ) {
                $this->mLinkID = $id;
        }

        /**
         * Get a language object for use in parser functions such as {{FORMATNUM:}}
         * @return Language
         * @since 1.7
         * @deprecated since 1.40; use ::getTargetLanguage() instead.
         */
        public function getFunctionLang() {
                wfDeprecated( __METHOD__, '1.40' );
                return $this->getTargetLanguage();
        }

        /**
         * Get the target language for the content being parsed. This is usually the
         * language that the content is in.
         *
         * @since 1.19
         *
         * @return Language
         */
        public function getTargetLanguage() {
                $target = $this->mOptions->getTargetLanguage();

                if ( $target !== null ) {
                        return $target;
                } elseif ( $this->mOptions->getInterfaceMessage() ) {
                        return $this->mOptions->getUserLangObj();
                }

                return $this->getTitle()->getPageLanguage();
        }

        /**
         * Get a user either from the user set on Parser if it's set,
         * or from the ParserOptions object otherwise.
         *
         * @since 1.36
         * @return UserIdentity
         */
        public function getUserIdentity(): UserIdentity {
                return $this->mUser ?? $this->getOptions()->getUserIdentity();
        }

        /**
         * Get a preprocessor object
         *
         * @return Preprocessor
         * @since 1.12.0
         */
        public function getPreprocessor() {
                return $this->mPreprocessor;
        }

        /**
         * Get a LinkRenderer instance to make links with
         *
         * @since 1.28
         * @return LinkRenderer
         */
        public function getLinkRenderer() {
                // XXX We make the LinkRenderer with current options and then cache it forever
                if ( !$this->mLinkRenderer ) {
                        $this->mLinkRenderer = $this->linkRendererFactory->create();
                }

                return $this->mLinkRenderer;
        }

        /**
         * Get the MagicWordFactory that this Parser is using
         *
         * @since 1.32
         * @return MagicWordFactory
         */
        public function getMagicWordFactory() {
                return $this->magicWordFactory;
        }

        /**
         * Get the content language that this Parser is using
         *
         * @since 1.32
         * @return Language
         */
        public function getContentLanguage() {
                return $this->contLang;
        }

        /**
         * Get the BadFileLookup instance that this Parser is using
         *
         * @since 1.35
         * @return BadFileLookup
         */
        public function getBadFileLookup() {
                return $this->badFileLookup;
        }

        /**
         * Replaces all occurrences of HTML-style comments and the given tags
         * in the text with a random marker and returns the next text. The output
         * parameter $matches will be an associative array filled with data in
         * the form:
         *
         * @code
         *   'UNIQ-xxxxx' => [
         *     'element',
         *     'tag content',
         *     [ 'param' => 'x' ],
         *     '<element param="x">tag content</element>' ]
         * @endcode
         *
         * @param string[] $elements List of element names. Comments are always extracted.
         * @param string $text Source text string.
         * @param array[] &$matches Out parameter, Array: extracted tags
         * @return string Stripped text
         */
        public static function extractTagsAndParams( array $elements, $text, &$matches ) {
                static $n = 1;
                $stripped = '';
                $matches = [];

                $taglist = implode( '|', $elements );
                $start = "/<($taglist)(\\s+[^>]*?|\\s*?)(\/?>)|<(!--)/i";

                while ( $text != '' ) {
                        $p = preg_split( $start, $text, 2, PREG_SPLIT_DELIM_CAPTURE );
                        $stripped .= $p[0];
                        if ( count( $p ) < 5 ) {
                                break;
                        }
                        if ( count( $p ) > 5 ) {
                                # comment
                                $element = $p[4];
                                $attributes = '';
                                $close = '';
                                $inside = $p[5];
                        } else {
                                # tag
                                [ , $element, $attributes, $close, $inside ] = $p;
                        }

                        $marker = self::MARKER_PREFIX . "-$element-" . sprintf( '%08X', $n++ ) . self::MARKER_SUFFIX;
                        $stripped .= $marker;

                        if ( $close === '/>' ) {
                                # Empty element tag, <tag />
                                $content = null;
                                $text = $inside;
                                $tail = null;
                        } else {
                                if ( $element === '!--' ) {
                                        $end = '/(-->)/';
                                } else {
                                        $end = "/(<\\/$element\\s*>)/i";
                                }
                                $q = preg_split( $end, $inside, 2, PREG_SPLIT_DELIM_CAPTURE );
                                $content = $q[0];
                                if ( count( $q ) < 3 ) {
                                        # No end tag -- let it run out to the end of the text.
                                        $tail = '';
                                        $text = '';
                                } else {
                                        [ , $tail, $text ] = $q;
                                }
                        }

                        $matches[$marker] = [ $element,
                                $content,
                                Sanitizer::decodeTagAttributes( $attributes ),
                                "<$element$attributes$close$content$tail" ];
                }
                return $stripped;
        }

        /**
         * Get a list of strippable XML-like elements
         *
         * @return array
         */
        public function getStripList() {
                return $this->mStripList;
        }

        /**
         * @return StripState
         * @since 1.34
         */
        public function getStripState() {
                return $this->mStripState;
        }

        /**
         * Add an item to the strip state
         * Returns the unique tag which must be inserted into the stripped text
         * The tag will be replaced with the original text in unstrip()
         *
         * @param string $text
         *
         * @return string
         */
        public function insertStripItem( $text ) {
                $marker = self::MARKER_PREFIX . "-item-{$this->mMarkerIndex}-" . self::MARKER_SUFFIX;
                $this->mMarkerIndex++;
                $this->mStripState->addGeneral( $marker, $text );
                return $marker;
        }

        /**
         * Parse the wiki syntax used to render tables.
         *
         * @param string $text
         * @return string
         */
        private function handleTables( $text ) {
                $lines = StringUtils::explode( "\n", $text );
                $out = '';
                $td_history = []; # Is currently a td tag open?
                $last_tag_history = []; # Save history of last lag activated (td, th or caption)
                $tr_history = []; # Is currently a tr tag open?
                $tr_attributes = []; # history of tr attributes
                $has_opened_tr = []; # Did this table open a <tr> element?
                $indent_level = 0; # indent level of the table

                foreach ( $lines as $outLine ) {
                        $line = trim( $outLine );

                        if ( $line === '' ) { # empty line, go to next line
                                $out .= $outLine . "\n";
                                continue;
                        }

                        $first_character = $line[0];
                        $first_two = substr( $line, 0, 2 );
                        $matches = [];

                        if ( preg_match( '/^(:*)\s*\{\|(.*)$/', $line, $matches ) ) {
                                # First check if we are starting a new table
                                $indent_level = strlen( $matches[1] );

                                $attributes = $this->mStripState->unstripBoth( $matches[2] );
                                $attributes = Sanitizer::fixTagAttributes( $attributes, 'table' );

                                $outLine = str_repeat( '<dl><dd>', $indent_level ) . "<table{$attributes}>";
                                $td_history[] = false;
                                $last_tag_history[] = '';
                                $tr_history[] = false;
                                $tr_attributes[] = '';
                                $has_opened_tr[] = false;
                        } elseif ( count( $td_history ) == 0 ) {
                                # Don't do any of the following
                                $out .= $outLine . "\n";
                                continue;
                        } elseif ( $first_two === '|}' ) {
                                # We are ending a table
                                $line = '</table>' . substr( $line, 2 );
                                $last_tag = array_pop( $last_tag_history );

                                if ( !array_pop( $has_opened_tr ) ) {
                                        $line = "<tr><td></td></tr>{$line}";
                                }

                                if ( array_pop( $tr_history ) ) {
                                        $line = "</tr>{$line}";
                                }

                                if ( array_pop( $td_history ) ) {
                                        $line = "</{$last_tag}>{$line}";
                                }
                                array_pop( $tr_attributes );
                                if ( $indent_level > 0 ) {
                                        $outLine = rtrim( $line ) . str_repeat( '</dd></dl>', $indent_level );
                                } else {
                                        $outLine = $line;
                                }
                        } elseif ( $first_two === '|-' ) {
                                # Now we have a table row
                                $line = preg_replace( '#^\|-+#', '', $line );

                                # Whats after the tag is now only attributes
                                $attributes = $this->mStripState->unstripBoth( $line );
                                $attributes = Sanitizer::fixTagAttributes( $attributes, 'tr' );
                                array_pop( $tr_attributes );
                                $tr_attributes[] = $attributes;

                                $line = '';
                                $last_tag = array_pop( $last_tag_history );
                                array_pop( $has_opened_tr );
                                $has_opened_tr[] = true;

                                if ( array_pop( $tr_history ) ) {
                                        $line = '</tr>';
                                }

                                if ( array_pop( $td_history ) ) {
                                        $line = "</{$last_tag}>{$line}";
                                }

                                $outLine = $line;
                                $tr_history[] = false;
                                $td_history[] = false;
                                $last_tag_history[] = '';
                        } elseif ( $first_character === '|'
                                || $first_character === '!'
                                || $first_two === '|+'
                        ) {
                                # This might be cell elements, td, th or captions
                                if ( $first_two === '|+' ) {
                                        $first_character = '+';
                                        $line = substr( $line, 2 );
                                } else {
                                        $line = substr( $line, 1 );
                                }

                                // Implies both are valid for table headings.
                                if ( $first_character === '!' ) {
                                        $line = StringUtils::replaceMarkup( '!!', '||', $line );
                                }

                                # Split up multiple cells on the same line.
                                # FIXME : This can result in improper nesting of tags processed
                                # by earlier parser steps.
                                $cells = explode( '||', $line );

                                $outLine = '';

                                # Loop through each table cell
                                foreach ( $cells as $cell ) {
                                        $previous = '';
                                        if ( $first_character !== '+' ) {
                                                $tr_after = array_pop( $tr_attributes );
                                                if ( !array_pop( $tr_history ) ) {
                                                        $previous = "<tr{$tr_after}>\n";
                                                }
                                                $tr_history[] = true;
                                                $tr_attributes[] = '';
                                                array_pop( $has_opened_tr );
                                                $has_opened_tr[] = true;
                                        }

                                        $last_tag = array_pop( $last_tag_history );

                                        if ( array_pop( $td_history ) ) {
                                                $previous = "</{$last_tag}>\n{$previous}";
                                        }

                                        if ( $first_character === '|' ) {
                                                $last_tag = 'td';
                                        } elseif ( $first_character === '!' ) {
                                                $last_tag = 'th';
                                        } elseif ( $first_character === '+' ) {
                                                $last_tag = 'caption';
                                        } else {
                                                $last_tag = '';
                                        }

                                        $last_tag_history[] = $last_tag;

                                        # A cell could contain both parameters and data
                                        $cell_data = explode( '|', $cell, 2 );

                                        # T2553: Note that a '|' inside an invalid link should not
                                        # be mistaken as delimiting cell parameters
                                        # Bug T153140: Neither should language converter markup.
                                        if ( preg_match( '/\[\[|-\{/', $cell_data[0] ) === 1 ) {
                                                $cell = "{$previous}<{$last_tag}>" . trim( $cell );
                                        } elseif ( count( $cell_data ) == 1 ) {
                                                // Whitespace in cells is trimmed
                                                $cell = "{$previous}<{$last_tag}>" . trim( $cell_data[0] );
                                        } else {
                                                $attributes = $this->mStripState->unstripBoth( $cell_data[0] );
                                                $attributes = Sanitizer::fixTagAttributes( $attributes, $last_tag );
                                                // Whitespace in cells is trimmed
                                                $cell = "{$previous}<{$last_tag}{$attributes}>" . trim( $cell_data[1] );
                                        }

                                        $outLine .= $cell;
                                        $td_history[] = true;
                                }
                        }
                        $out .= $outLine . "\n";
                }

                # Closing open td, tr && table
                while ( count( $td_history ) > 0 ) {
                        if ( array_pop( $td_history ) ) {
                                $out .= "</td>\n";
                        }
                        if ( array_pop( $tr_history ) ) {
                                $out .= "</tr>\n";
                        }
                        if ( !array_pop( $has_opened_tr ) ) {
                                $out .= "<tr><td></td></tr>\n";
                        }

                        $out .= "</table>\n";
                }

                # Remove trailing line-ending (b/c)
                if ( substr( $out, -1 ) === "\n" ) {
                        $out = substr( $out, 0, -1 );
                }

                # special case: don't return empty table
                if ( $out === "<table>\n<tr><td></td></tr>\n</table>" ) {
                        $out = '';
                }

                return $out;
        }

        /**
         * Helper function for parse() that transforms wiki markup into half-parsed
         * HTML. Only called for $mOutputType == self::OT_HTML.
         *
         * @internal
         *
         * @param string $text The text to parse
         * @param-taint $text escapes_html
         * @param bool $isMain Whether this is being called from the main parse() function
         * @param PPFrame|false $frame A pre-processor frame
         *
         * @return string
         */
        public function internalParse( $text, $isMain = true, $frame = false ) {
                $origText = $text;

                # Hook to suspend the parser in this state
                if ( !$this->hookRunner->onParserBeforeInternalParse( $this, $text, $this->mStripState ) ) {
                        return $text;
                }

                # if $frame is provided, then use $frame for replacing any variables
                if ( $frame ) {
                        # use frame depth to infer how include/noinclude tags should be handled
                        # depth=0 means this is the top-level document; otherwise it's an included document
                        if ( !$frame->depth ) {
                                $flag = 0;
                        } else {
                                $flag = Preprocessor::DOM_FOR_INCLUSION;
                        }
                        $dom = $this->preprocessToDom( $text, $flag );
                        $text = $frame->expand( $dom );
                } else {
                        # if $frame is not provided, then use old-style replaceVariables
                        $text = $this->replaceVariables( $text );
                }

                $text = Sanitizer::internalRemoveHtmlTags(
                        $text,
                        // Callback from the Sanitizer for expanding items found in
                        // HTML attribute values, so they can be safely tested and escaped.
                        function ( &$text, $frame = false ) {
                                $text = $this->replaceVariables( $text, $frame );
                                $text = $this->mStripState->unstripBoth( $text );
                        },
                        false,
                        [],
                        []
                );
                $this->hookRunner->onInternalParseBeforeLinks( $this, $text, $this->mStripState );

                # Tables need to come after variable replacement for things to work
                # properly; putting them before other transformations should keep
                # exciting things like link expansions from showing up in surprising
                # places.
                $text = $this->handleTables( $text );

                $text = preg_replace( '/(^|\n)-----*/', '\\1<hr />', $text );

                $text = $this->handleDoubleUnderscore( $text );

                $text = $this->handleHeadings( $text );
                $text = $this->handleInternalLinks( $text );
                $text = $this->handleAllQuotes( $text );
                $text = $this->handleExternalLinks( $text );

                # handleInternalLinks may sometimes leave behind
                # absolute URLs, which have to be masked to hide them from handleExternalLinks
                $text = str_replace( self::MARKER_PREFIX . 'NOPARSE', '', $text );

                $text = $this->handleMagicLinks( $text );
                $text = $this->finalizeHeadings( $text, $origText, $isMain );

                return $text;
        }

        /**
         * Shorthand for getting a Language Converter for Target language
         *
         * @since public since 1.38
         * @return ILanguageConverter
         */
        public function getTargetLanguageConverter(): ILanguageConverter {
                return $this->languageConverterFactory->getLanguageConverter(
                        $this->getTargetLanguage()
                );
        }

        /**
         * Shorthand for getting a Language Converter for Content language
         *
         * @return ILanguageConverter
         */
        private function getContentLanguageConverter(): ILanguageConverter {
                return $this->languageConverterFactory->getLanguageConverter(
                        $this->getContentLanguage()
                );
        }

        /**
         * Get a HookContainer capable of returning metadata about hooks or running
         * extension hooks.
         *
         * @since 1.35
         * @return HookContainer
         */
        protected function getHookContainer() {
                return $this->hookContainer;
        }

        /**
         * Get a HookRunner for calling core hooks
         *
         * @internal This is for use by core only. Hook interfaces may be removed
         *   without notice.
         * @since 1.35
         * @return HookRunner
         */
        protected function getHookRunner() {
                return $this->hookRunner;
        }

        /**
         * Helper function for parse() that transforms half-parsed HTML into fully
         * parsed HTML.
         *
         * @param string $text
         * @param bool $isMain
         * @param bool $linestart
         * @return string
         */
        private function internalParseHalfParsed( $text, $isMain = true, $linestart = true ) {
                $text = $this->mStripState->unstripGeneral( $text );

                $text = BlockLevelPass::doBlockLevels( $text, $linestart );

                $this->replaceLinkHoldersPrivate( $text );

                /**
                 * The input doesn't get language converted if
                 * a) It's disabled
                 * b) Content isn't converted
                 * c) It's a conversion table
                 * d) it is an interface message (which is in the user language)
                 */
                $converter = null;
                if ( !( $this->mOptions->getDisableContentConversion()
                        || isset( $this->mDoubleUnderscores['nocontentconvert'] )
                        || $this->mOptions->getInterfaceMessage() )
                ) {
                        # The position of the convert() call should not be changed. it
                        # assumes that the links are all replaced and the only thing left
                        # is the <nowiki> mark.
                        $converter = $this->getTargetLanguageConverter();
                        $text = $converter->convert( $text );
                        // TOC will be converted below.
                }
                // Convert the TOC.   This is done *after* the main text
                // so that all the editor-defined conversion rules (by convention
                // defined at the start of the article) are applied to the TOC
                self::localizeTOC(
                        $this->mOutput->getTOCData(),
                        $this->getTargetLanguage(),
                        $converter // null if conversion is to be suppressed.
                );
                if ( $converter ) {
                        $this->mOutput->setLanguage( new Bcp47CodeValue(
                                LanguageCode::bcp47( $converter->getPreferredVariant() )
                        ) );
                } else {
                        $this->mOutput->setLanguage( $this->getTargetLanguage() );
                }

                $text = $this->mStripState->unstripNoWiki( $text );

                $text = $this->mStripState->unstripGeneral( $text );

                $text = $this->tidy->tidy( $text, [ Sanitizer::class, 'armorFrenchSpaces' ] );

                if ( $isMain ) {
                        $this->hookRunner->onParserAfterTidy( $this, $text );
                }

                return $text;
        }

        /**
         * Replace special strings like "ISBN xxx" and "RFC xxx" with
         * magic external links.
         *
         * DML
         *
         * @param string $text
         *
         * @return string
         */
        private function handleMagicLinks( $text ) {
                $prots = $this->urlUtils->validAbsoluteProtocols();
                $urlChar = self::EXT_LINK_URL_CLASS;
                $addr = self::EXT_LINK_ADDR;
                $space = self::SPACE_NOT_NL; #  non-newline space
                $spdash = "(?:-|$space)"; # a dash or a non-newline space
                $spaces = "$space++"; # possessive match of 1 or more spaces
                $text = preg_replace_callback(
                        '!(?:                        # Start cases
                                (<a[ \t\r\n>].*?</a>) |    # m[1]: Skip link text
                                (<.*?>) |                  # m[2]: Skip stuff inside HTML elements' . "
                                (\b                        # m[3]: Free external links
                                        (?i:$prots)
                                        ($addr$urlChar*)         # m[4]: Post-protocol path
                                ) |
                                \b(?:RFC|PMID) $spaces     # m[5]: RFC or PMID, capture number
                                        ([0-9]+)\b |
                                \bISBN $spaces (           # m[6]: ISBN, capture number
                                        (?: 97[89] $spdash? )?   #  optional 13-digit ISBN prefix
                                        (?: [0-9]  $spdash? ){9} #  9 digits with opt. delimiters
                                        [0-9Xx]                  #  check digit
                                )\b
                        )!xu",
                        [ $this, 'magicLinkCallback' ],
                        $text
                );
                return $text;
        }

        /**
         * @param array $m
         * @return string HTML
         */
        private function magicLinkCallback( array $m ) {
                if ( isset( $m[1] ) && $m[1] !== '' ) {
                        # Skip anchor
                        return $m[0];
                } elseif ( isset( $m[2] ) && $m[2] !== '' ) {
                        # Skip HTML element
                        return $m[0];
                } elseif ( isset( $m[3] ) && $m[3] !== '' ) {
                        # Free external link
                        return $this->makeFreeExternalLink( $m[0], strlen( $m[4] ) );
                } elseif ( isset( $m[5] ) && $m[5] !== '' ) {
                        # RFC or PMID
                        if ( substr( $m[0], 0, 3 ) === 'RFC' ) {
                                if ( !$this->mOptions->getMagicRFCLinks() ) {
                                        return $m[0];
                                }
                                $keyword = 'RFC';
                                $urlmsg = 'rfcurl';
                                $cssClass = 'mw-magiclink-rfc';
                                $trackingCat = 'magiclink-tracking-rfc';
                                $id = $m[5];
                        } elseif ( substr( $m[0], 0, 4 ) === 'PMID' ) {
                                if ( !$this->mOptions->getMagicPMIDLinks() ) {
                                        return $m[0];
                                }
                                $keyword = 'PMID';
                                $urlmsg = 'pubmedurl';
                                $cssClass = 'mw-magiclink-pmid';
                                $trackingCat = 'magiclink-tracking-pmid';
                                $id = $m[5];
                        } else {
                                // Should never happen
                                throw new UnexpectedValueException( __METHOD__ . ': unrecognised match type "' .
                                        substr( $m[0], 0, 20 ) . '"' );
                        }
                        $url = wfMessage( $urlmsg, $id )->inContentLanguage()->text();
                        $this->addTrackingCategory( $trackingCat );
                        return Linker::makeExternalLink(
                                $url,
                                "{$keyword} {$id}",
                                true,
                                $cssClass,
                                [],
                                $this->getTitle()
                        );
                } elseif ( isset( $m[6] ) && $m[6] !== ''
                        && $this->mOptions->getMagicISBNLinks()
                ) {
                        # ISBN
                        $isbn = $m[6];
                        $space = self::SPACE_NOT_NL; #  non-newline space
                        $isbn = preg_replace( "/$space/", ' ', $isbn );
                        $num = strtr( $isbn, [
                                '-' => '',
                                ' ' => '',
                                'x' => 'X',
                        ] );
                        $this->addTrackingCategory( 'magiclink-tracking-isbn' );
                        return $this->getLinkRenderer()->makeKnownLink(
                                SpecialPage::getTitleFor( 'Booksources', $num ),
                                "ISBN $isbn",
                                [
                                        'class' => 'internal mw-magiclink-isbn',
                                        'title' => false // suppress title attribute
                                ]
                        );
                } else {
                        return $m[0];
                }
        }

        /**
         * Make a free external link, given a user-supplied URL
         *
         * @param string $url
         * @param int $numPostProto
         *   The number of characters after the protocol.
         * @return string HTML
         * @internal
         */
        private function makeFreeExternalLink( $url, $numPostProto ) {
                $trail = '';

                # The characters '<' and '>' (which were escaped by
                # internalRemoveHtmlTags()) should not be included in
                # URLs, per RFC 2396.
                # Make &nbsp; terminate a URL as well (bug T84937)
                $m2 = [];
                if ( preg_match(
                        '/&(lt|gt|nbsp|#x0*(3[CcEe]|[Aa]0)|#0*(60|62|160));/',
                        $url,
                        $m2,
                        PREG_OFFSET_CAPTURE
                ) ) {
                        $trail = substr( $url, $m2[0][1] ) . $trail;
                        $url = substr( $url, 0, $m2[0][1] );
                }

                # Move trailing punctuation to $trail
                $sep = ',;\.:!?';
                # If there is no left bracket, then consider right brackets fair game too
                if ( strpos( $url, '(' ) === false ) {
                        $sep .= ')';
                }

                $urlRev = strrev( $url );
                $numSepChars = strspn( $urlRev, $sep );
                # Don't break a trailing HTML entity by moving the ; into $trail
                # This is in hot code, so use substr_compare to avoid having to
                # create a new string object for the comparison
                if ( $numSepChars && substr_compare( $url, ";", -$numSepChars, 1 ) === 0 ) {
                        # more optimization: instead of running preg_match with a $
                        # anchor, which can be slow, do the match on the reversed
                        # string starting at the desired offset.
                        # un-reversed regexp is: /&([a-z]+|#x[\da-f]+|#\d+)$/i
                        if ( preg_match( '/\G([a-z]+|[\da-f]+x#|\d+#)&/i', $urlRev, $m2, 0, $numSepChars ) ) {
                                $numSepChars--;
                        }
                }
                if ( $numSepChars ) {
                        $trail = substr( $url, -$numSepChars ) . $trail;
                        $url = substr( $url, 0, -$numSepChars );
                }

                # Verify that we still have a real URL after trail removal, and
                # not just lone protocol
                if ( strlen( $trail ) >= $numPostProto ) {
                        return $url . $trail;
                }

                $url = Sanitizer::cleanUrl( $url );

                # Is this an external image?
                $text = $this->maybeMakeExternalImage( $url );
                if ( $text === false ) {
                        # Not an image, make a link
                        $text = Linker::makeExternalLink(
                                $url,
                                $this->getTargetLanguageConverter()->markNoConversion( $url ),
                                true,
                                'free',
                                $this->getExternalLinkAttribs( $url ),
                                $this->getTitle()
                        );
                        # Register it in the output object...
                        $this->mOutput->addExternalLink( $url );
                }
                return $text . $trail;
        }

        /**
         * Parse headers and return html
         *
         * @param string $text
         * @return string
         */
        private function handleHeadings( $text ) {
                for ( $i = 6; $i >= 1; --$i ) {
                        $h = str_repeat( '=', $i );
                        // Trim non-newline whitespace from headings
                        // Using \s* will break for: "==\n===\n" and parse as <h2>=</h2>
                        $text = preg_replace( "/^(?:$h)[ \\t]*(.+?)[ \\t]*(?:$h)\\s*$/m", "<h$i>\\1</h$i>", $text );
                }
                return $text;
        }

        /**
         * Replace single quotes with HTML markup
         *
         * @param string $text
         *
         * @return string The altered text
         */
        private function handleAllQuotes( $text ) {
                $outtext = '';
                $lines = StringUtils::explode( "\n", $text );
                foreach ( $lines as $line ) {
                        $outtext .= $this->doQuotes( $line ) . "\n";
                }
                $outtext = substr( $outtext, 0, -1 );
                return $outtext;
        }

        /**
         * Helper function for handleAllQuotes()
         *
         * @param string $text
         *
         * @return string
         * @internal
         */
        public function doQuotes( $text ) {
                $arr = preg_split( "/(''+)/", $text, -1, PREG_SPLIT_DELIM_CAPTURE );
                $countarr = count( $arr );
                if ( $countarr == 1 ) {
                        return $text;
                }

                // First, do some preliminary work. This may shift some apostrophes from
                // being mark-up to being text. It also counts the number of occurrences
                // of bold and italics mark-ups.
                $numbold = 0;
                $numitalics = 0;
                for ( $i = 1; $i < $countarr; $i += 2 ) {
                        $thislen = strlen( $arr[$i] );
                        // If there are ever four apostrophes, assume the first is supposed to
                        // be text, and the remaining three constitute mark-up for bold text.
                        // (T15227: ''''foo'''' turns into ' ''' foo ' ''')
                        if ( $thislen == 4 ) {
                                $arr[$i - 1] .= "'";
                                $arr[$i] = "'''";
                                $thislen = 3;
                        } elseif ( $thislen > 5 ) {
                                // If there are more than 5 apostrophes in a row, assume they're all
                                // text except for the last 5.
                                // (T15227: ''''''foo'''''' turns into ' ''''' foo ' ''''')
                                $arr[$i - 1] .= str_repeat( "'", $thislen - 5 );
                                $arr[$i] = "'''''";
                                $thislen = 5;
                        }
                        // Count the number of occurrences of bold and italics mark-ups.
                        if ( $thislen == 2 ) {
                                $numitalics++;
                        } elseif ( $thislen == 3 ) {
                                $numbold++;
                        } elseif ( $thislen == 5 ) {
                                $numitalics++;
                                $numbold++;
                        }
                }

                // If there is an odd number of both bold and italics, it is likely
                // that one of the bold ones was meant to be an apostrophe followed
                // by italics. Which one we cannot know for certain, but it is more
                // likely to be one that has a single-letter word before it.
                if ( ( $numbold % 2 == 1 ) && ( $numitalics % 2 == 1 ) ) {
                        $firstsingleletterword = -1;
                        $firstmultiletterword = -1;
                        $firstspace = -1;
                        for ( $i = 1; $i < $countarr; $i += 2 ) {
                                if ( strlen( $arr[$i] ) == 3 ) {
                                        $x1 = substr( $arr[$i - 1], -1 );
                                        $x2 = substr( $arr[$i - 1], -2, 1 );
                                        if ( $x1 === ' ' ) {
                                                if ( $firstspace == -1 ) {
                                                        $firstspace = $i;
                                                }
                                        } elseif ( $x2 === ' ' ) {
                                                $firstsingleletterword = $i;
                                                // if $firstsingleletterword is set, we don't
                                                // look at the other options, so we can bail early.
                                                break;
                                        } elseif ( $firstmultiletterword == -1 ) {
                                                $firstmultiletterword = $i;
                                        }
                                }
                        }

                        // If there is a single-letter word, use it!
                        if ( $firstsingleletterword > -1 ) {
                                $arr[$firstsingleletterword] = "''";
                                $arr[$firstsingleletterword - 1] .= "'";
                        } elseif ( $firstmultiletterword > -1 ) {
                                // If not, but there's a multi-letter word, use that one.
                                $arr[$firstmultiletterword] = "''";
                                $arr[$firstmultiletterword - 1] .= "'";
                        } elseif ( $firstspace > -1 ) {
                                // ... otherwise use the first one that has neither.
                                // (notice that it is possible for all three to be -1 if, for example,
                                // there is only one pentuple-apostrophe in the line)
                                $arr[$firstspace] = "''";
                                $arr[$firstspace - 1] .= "'";
                        }
                }

                // Now let's actually convert our apostrophic mush to HTML!
                $output = '';
                $buffer = '';
                $state = '';
                $i = 0;
                foreach ( $arr as $r ) {
                        if ( ( $i % 2 ) == 0 ) {
                                if ( $state === 'both' ) {
                                        $buffer .= $r;
                                } else {
                                        $output .= $r;
                                }
                        } else {
                                $thislen = strlen( $r );
                                if ( $thislen == 2 ) {
                                        // two quotes - open or close italics
                                        if ( $state === 'i' ) {
                                                $output .= '</i>';
                                                $state = '';
                                        } elseif ( $state === 'bi' ) {
                                                $output .= '</i>';
                                                $state = 'b';
                                        } elseif ( $state === 'ib' ) {
                                                $output .= '</b></i><b>';
                                                $state = 'b';
                                        } elseif ( $state === 'both' ) {
                                                $output .= '<b><i>' . $buffer . '</i>';
                                                $state = 'b';
                                        } else { // $state can be 'b' or ''
                                                $output .= '<i>';
                                                $state .= 'i';
                                        }
                                } elseif ( $thislen == 3 ) {
                                        // three quotes - open or close bold
                                        if ( $state === 'b' ) {
                                                $output .= '</b>';
                                                $state = '';
                                        } elseif ( $state === 'bi' ) {
                                                $output .= '</i></b><i>';
                                                $state = 'i';
                                        } elseif ( $state === 'ib' ) {
                                                $output .= '</b>';
                                                $state = 'i';
                                        } elseif ( $state === 'both' ) {
                                                $output .= '<i><b>' . $buffer . '</b>';
                                                $state = 'i';
                                        } else { // $state can be 'i' or ''
                                                $output .= '<b>';
                                                $state .= 'b';
                                        }
                                } elseif ( $thislen == 5 ) {
                                        // five quotes - open or close both separately
                                        if ( $state === 'b' ) {
                                                $output .= '</b><i>';
                                                $state = 'i';
                                        } elseif ( $state === 'i' ) {
                                                $output .= '</i><b>';
                                                $state = 'b';
                                        } elseif ( $state === 'bi' ) {
                                                $output .= '</i></b>';
                                                $state = '';
                                        } elseif ( $state === 'ib' ) {
                                                $output .= '</b></i>';
                                                $state = '';
                                        } elseif ( $state === 'both' ) {
                                                $output .= '<i><b>' . $buffer . '</b></i>';
                                                $state = '';
                                        } else { // ($state == '')
                                                $buffer = '';
                                                $state = 'both';
                                        }
                                }
                        }
                        $i++;
                }
                // Now close all remaining tags.  Notice that the order is important.
                if ( $state === 'b' || $state === 'ib' ) {
                        $output .= '</b>';
                }
                if ( $state === 'i' || $state === 'bi' || $state === 'ib' ) {
                        $output .= '</i>';
                }
                if ( $state === 'bi' ) {
                        $output .= '</b>';
                }
                // There might be lonely ''''', so make sure we have a buffer
                if ( $state === 'both' && $buffer ) {
                        $output .= '<b><i>' . $buffer . '</i></b>';
                }
                return $output;
        }

        /**
         * Replace external links (REL)
         *
         * Note: this is all very hackish and the order of execution matters a lot.
         * Make sure to run tests/parser/parserTests.php if you change this code.
         *
         * @param string $text
         * @return string
         */
        private function handleExternalLinks( $text ) {
                $bits = preg_split( $this->mExtLinkBracketedRegex, $text, -1, PREG_SPLIT_DELIM_CAPTURE );
                // @phan-suppress-next-line PhanTypeComparisonFromArray See phan issue #3161
                if ( $bits === false ) {
                        throw new RuntimeException( "PCRE failure" );
                }
                $s = array_shift( $bits );

                $i = 0;
                while ( $i < count( $bits ) ) {
                        $url = $bits[$i++];
                        $i++; // protocol
                        $text = $bits[$i++];
                        $trail = $bits[$i++];

                        # The characters '<' and '>' (which were escaped by
                        # internalRemoveHtmlTags()) should not be included in
                        # URLs, per RFC 2396.
                        $m2 = [];
                        if ( preg_match( '/&(lt|gt);/', $url, $m2, PREG_OFFSET_CAPTURE ) ) {
                                $text = substr( $url, $m2[0][1] ) . ' ' . $text;
                                $url = substr( $url, 0, $m2[0][1] );
                        }

                        # If the link text is an image URL, replace it with an <img> tag
                        # This happened by accident in the original parser, but some people used it extensively
                        $img = $this->maybeMakeExternalImage( $text );
                        if ( $img !== false ) {
                                $text = $img;
                        }

                        $dtrail = '';

                        # Set linktype for CSS
                        $linktype = 'text';

                        # No link text, e.g. [http://domain.tld/some.link]
                        if ( $text == '' ) {
                                # Autonumber
                                $langObj = $this->getTargetLanguage();
                                $text = '[' . $langObj->formatNum( ++$this->mAutonumber ) . ']';
                                $linktype = 'autonumber';
                        } else {
                                # Have link text, e.g. [http://domain.tld/some.link text]s
                                # Check for trail
                                [ $dtrail, $trail ] = Linker::splitTrail( $trail );
                        }

                        // Excluding protocol-relative URLs may avoid many false positives.
                        if ( preg_match( '/^(?:' . $this->urlUtils->validAbsoluteProtocols() . ')/', $text ) ) {
                                $text = $this->getTargetLanguageConverter()->markNoConversion( $text );
                        }

                        $url = Sanitizer::cleanUrl( $url );

                        # Use the encoded URL
                        # This means that users can paste URLs directly into the text
                        # Funny characters like ö aren't valid in URLs anyway
                        # This was changed in August 2004
                        $s .= Linker::makeExternalLink( $url, $text, false, $linktype,
                                $this->getExternalLinkAttribs( $url ), $this->getTitle() ) . $dtrail . $trail;

                        # Register link in the output object.
                        $this->mOutput->addExternalLink( $url );
                }

                // @phan-suppress-next-line PhanTypeMismatchReturnNullable False positive from array_shift
                return $s;
        }

        /**
         * Get the rel attribute for a particular external link.
         *
         * @since 1.21
         * @internal
         * @param string|false $url Optional URL, to extract the domain from for rel =>
         *   nofollow if appropriate
         * @param LinkTarget|null $title Optional LinkTarget, for wgNoFollowNsExceptions lookups
         * @return string|null Rel attribute for $url
         */
        public static function getExternalLinkRel( $url = false, LinkTarget $title = null ) {
                $mainConfig = MediaWikiServices::getInstance()->getMainConfig();
                $noFollowLinks = $mainConfig->get( MainConfigNames::NoFollowLinks );
                $noFollowNsExceptions = $mainConfig->get( MainConfigNames::NoFollowNsExceptions );
                $noFollowDomainExceptions = $mainConfig->get( MainConfigNames::NoFollowDomainExceptions );
                $ns = $title ? $title->getNamespace() : false;
                if ( $noFollowLinks && !in_array( $ns, $noFollowNsExceptions )
                        && !wfMatchesDomainList( $url, $noFollowDomainExceptions )
                ) {
                        return 'nofollow';
                }
                return null;
        }

        /**
         * Get an associative array of additional HTML attributes appropriate for a
         * particular external link.  This currently may include rel => nofollow
         * (depending on configuration, namespace, and the URL's domain) and/or a
         * target attribute (depending on configuration).
         *
         * @internal
         * @param string $url URL to extract the domain from for rel =>
         *   nofollow if appropriate
         * @return array Associative array of HTML attributes
         */
        public function getExternalLinkAttribs( $url ) {
                $attribs = [];
                $rel = self::getExternalLinkRel( $url, $this->getTitle() ) ?? '';

                $target = $this->mOptions->getExternalLinkTarget();
                if ( $target ) {
                        $attribs['target'] = $target;
                        if ( !in_array( $target, [ '_self', '_parent', '_top' ] ) ) {
                                // T133507. New windows can navigate parent cross-origin.
                                // Including noreferrer due to lacking browser
                                // support of noopener. Eventually noreferrer should be removed.
                                if ( $rel !== '' ) {
                                        $rel .= ' ';
                                }
                                $rel .= 'noreferrer noopener';
                        }
                }
                if ( $rel !== '' ) {
                        $attribs['rel'] = $rel;
                }
                return $attribs;
        }

        /**
         * Replace unusual escape codes in a URL with their equivalent characters
         *
         * This generally follows the syntax defined in RFC 3986, with special
         * consideration for HTTP query strings.
         *
         * @internal
         * @param string $url
         * @return string
         */
        public static function normalizeLinkUrl( $url ) {
                # Test for RFC 3986 IPv6 syntax
                $scheme = '[a-z][a-z0-9+.-]*:';
                $userinfo = '(?:[a-z0-9\-._~!$&\'()*+,;=:]|%[0-9a-f]{2})*';
                $ipv6Host = '\\[((?:[0-9a-f:]|%3[0-A]|%[46][1-6])+)\\]';
                if ( preg_match( "<^(?:{$scheme})?//(?:{$userinfo}@)?{$ipv6Host}(?:[:/?#].*|)$>i", $url, $m ) &&
                        IPUtils::isValid( rawurldecode( $m[1] ) )
                ) {
                        $isIPv6 = rawurldecode( $m[1] );
                } else {
                        $isIPv6 = false;
                }

                # Make sure unsafe characters are encoded
                $url = preg_replace_callback(
                        '/[\x00-\x20"<>\[\\\\\]^`{|}\x7F-\xFF]/',
                        static function ( $m ) {
                                return rawurlencode( $m[0] );
                        },
                        $url
                );

                $ret = '';
                $end = strlen( $url );

                # Fragment part - 'fragment'
                $start = strpos( $url, '#' );
                if ( $start !== false && $start < $end ) {
                        $ret = self::normalizeUrlComponent(
                                substr( $url, $start, $end - $start ), '"#%<>[\]^`{|}' ) . $ret;
                        $end = $start;
                }

                # Query part - 'query' minus &=+;
                $start = strpos( $url, '?' );
                if ( $start !== false && $start < $end ) {
                        $ret = self::normalizeUrlComponent(
                                substr( $url, $start, $end - $start ), '"#%<>[\]^`{|}&=+;' ) . $ret;
                        $end = $start;
                }

                # Scheme and path part - 'pchar'
                # (we assume no userinfo or encoded colons in the host)
                $ret = self::normalizeUrlComponent(
                        substr( $url, 0, $end ), '"#%<>[\]^`{|}/?' ) . $ret;

                # Fix IPv6 syntax
                if ( $isIPv6 !== false ) {
                        $ipv6Host = "%5B({$isIPv6})%5D";
                        $ret = preg_replace(
                                "<^((?:{$scheme})?//(?:{$userinfo}@)?){$ipv6Host}(?=[:/?#]|$)>i",
                                "$1[$2]",
                                $ret
                        );
                }

                return $ret;
        }

        private static function normalizeUrlComponent( $component, $unsafe ) {
                $callback = static function ( $matches ) use ( $unsafe ) {
                        $char = urldecode( $matches[0] );
                        $ord = ord( $char );
                        if ( $ord > 32 && $ord < 127 && strpos( $unsafe, $char ) === false ) {
                                # Unescape it
                                return $char;
                        } else {
                                # Leave it escaped, but use uppercase for a-f
                                return strtoupper( $matches[0] );
                        }
                };
                return preg_replace_callback( '/%[0-9A-Fa-f]{2}/', $callback, $component );
        }

        /**
         * make an image if it's allowed, either through the global
         * option, through the exception, or through the on-wiki whitelist
         *
         * @param string $url
         *
         * @return string
         */
        private function maybeMakeExternalImage( $url ) {
                $imagesfrom = $this->mOptions->getAllowExternalImagesFrom();
                $imagesexception = (bool)$imagesfrom;
                $text = false;
                # $imagesfrom could be either a single string or an array of strings, parse out the latter
                if ( $imagesexception && is_array( $imagesfrom ) ) {
                        $imagematch = false;
                        foreach ( $imagesfrom as $match ) {
                                if ( strpos( $url, $match ) === 0 ) {
                                        $imagematch = true;
                                        break;
                                }
                        }
                } elseif ( $imagesexception ) {
                        $imagematch = ( strpos( $url, $imagesfrom ) === 0 );
                } else {
                        $imagematch = false;
                }

                if ( $this->mOptions->getAllowExternalImages()
                        || ( $imagesexception && $imagematch )
                ) {
                        if ( preg_match( self::EXT_IMAGE_REGEX, $url ) ) {
                                # Image found
                                $text = Linker::makeExternalImage( $url );
                        }
                }
                if ( !$text && $this->mOptions->getEnableImageWhitelist()
                        && preg_match( self::EXT_IMAGE_REGEX, $url )
                ) {
                        $whitelist = explode(
                                "\n",
                                wfMessage( 'external_image_whitelist' )->inContentLanguage()->text()
                        );

                        foreach ( $whitelist as $entry ) {
                                # Sanitize the regex fragment, make it case-insensitive, ignore blank entries/comments
                                if ( strpos( $entry, '#' ) === 0 || $entry === '' ) {
                                        continue;
                                }
                                // @phan-suppress-next-line SecurityCheck-ReDoS preg_quote is not wanted here
                                if ( preg_match( '/' . str_replace( '/', '\\/', $entry ) . '/i', $url ) ) {
                                        # Image matches a whitelist entry
                                        $text = Linker::makeExternalImage( $url );
                                        break;
                                }
                        }
                }
                return $text;
        }

        /**
         * Process [[ ]] wikilinks
         *
         * @param string $text
         *
         * @return string Processed text
         */
        private function handleInternalLinks( $text ) {
                $this->mLinkHolders->merge( $this->handleInternalLinks2( $text ) );
                return $text;
        }

        /**
         * Process [[ ]] wikilinks (RIL)
         * @param string &$s
         * @return LinkHolderArray
         */
        private function handleInternalLinks2( &$s ) {
                static $tc = false, $e1, $e1_img;
                # the % is needed to support urlencoded titles as well
                if ( !$tc ) {
                        $tc = Title::legalChars() . '#%';
                        # Match a link having the form [[namespace:link|alternate]]trail
                        $e1 = "/^([{$tc}]+)(?:\\|(.+?))?]](.*)\$/sD";
                        # Match cases where there is no "]]", which might still be images
                        $e1_img = "/^([{$tc}]+)\\|(.*)\$/sD";
                }

                $holders = new LinkHolderArray(
                        $this,
                        $this->getContentLanguageConverter(),
                        $this->getHookContainer() );

                # split the entire text string on occurrences of [[
                $a = StringUtils::explode( '[[', ' ' . $s );
                # get the first element (all text up to first [[), and remove the space we added
                $s = $a->current();
                $a->next();
                $line = $a->current(); # Workaround for broken ArrayIterator::next() that returns "void"
                $s = substr( $s, 1 );

                $nottalk = !$this->getTitle()->isTalkPage();

                $useLinkPrefixExtension = $this->getTargetLanguage()->linkPrefixExtension();
                $e2 = null;
                if ( $useLinkPrefixExtension ) {
                        # Match the end of a line for a word that's not followed by whitespace,
                        # e.g. in the case of 'The Arab al[[Razi]]', 'al' will be matched
                        $charset = $this->contLang->linkPrefixCharset();
                        $e2 = "/^((?>.*[^$charset]|))(.+)$/sDu";
                        $m = [];
                        if ( preg_match( $e2, $s, $m ) ) {
                                $first_prefix = $m[2];
                        } else {
                                $first_prefix = false;
                        }
                        $prefix = false;
                } else {
                        $first_prefix = false;
                        $prefix = '';
                }

                # Some namespaces don't allow subpages
                $useSubpages = $this->nsInfo->hasSubpages(
                        $this->getTitle()->getNamespace()
                );

                # Loop for each link
                for ( ; $line !== false && $line !== null; $a->next(), $line = $a->current() ) {
                        # Check for excessive memory usage
                        if ( $holders->isBig() ) {
                                # Too big
                                # Do the existence check, replace the link holders and clear the array
                                $holders->replace( $s );
                                $holders->clear();
                        }

                        if ( $useLinkPrefixExtension ) {
                                // @phan-suppress-next-line PhanTypeMismatchArgumentNullableInternal $e2 is set under this condition
                                if ( preg_match( $e2, $s, $m ) ) {
                                        [ , $s, $prefix ] = $m;
                                } else {
                                        $prefix = '';
                                }
                                # first link
                                if ( $first_prefix ) {
                                        $prefix = $first_prefix;
                                        $first_prefix = false;
                                }
                        }

                        $might_be_img = false;

                        if ( preg_match( $e1, $line, $m ) ) { # page with normal text or alt
                                $text = $m[2];
                                # If we get a ] at the beginning of $m[3] that means we have a link that's something like:
                                # [[Image:Foo.jpg|[http://example.com desc]]] <- having three ] in a row fucks up,
                                # the real problem is with the $e1 regex
                                # See T1500.
                                # Still some problems for cases where the ] is meant to be outside punctuation,
                                # and no image is in sight. See T4095.
                                if ( $text !== ''
                                        && substr( $m[3], 0, 1 ) === ']'
                                        && strpos( $text, '[' ) !== false
                                ) {
                                        $text .= ']'; # so that handleExternalLinks($text) works later
                                        $m[3] = substr( $m[3], 1 );
                                }
                                # fix up urlencoded title texts
                                if ( strpos( $m[1], '%' ) !== false ) {
                                        # Should anchors '#' also be rejected?
                                        $m[1] = str_replace( [ '<', '>' ], [ '&lt;', '&gt;' ], rawurldecode( $m[1] ) );
                                }
                                $trail = $m[3];
                        } elseif ( preg_match( $e1_img, $line, $m ) ) {
                                # Invalid, but might be an image with a link in its caption
                                $might_be_img = true;
                                $text = $m[2];
                                if ( strpos( $m[1], '%' ) !== false ) {
                                        $m[1] = str_replace( [ '<', '>' ], [ '&lt;', '&gt;' ], rawurldecode( $m[1] ) );
                                }
                                $trail = "";
                        } else { # Invalid form; output directly
                                $s .= $prefix . '[[' . $line;
                                continue;
                        }

                        // @phan-suppress-next-line PhanTypePossiblyInvalidDimOffset preg_match success when reached here
                        $origLink = ltrim( $m[1], ' ' );

                        # Don't allow internal links to pages containing
                        # PROTO: where PROTO is a valid URL protocol; these
                        # should be external links.
                        if ( preg_match( '/^(?i:' . $this->urlUtils->validProtocols() . ')/', $origLink ) ) {
                                $s .= $prefix . '[[' . $line;
                                continue;
                        }

                        # Make subpage if necessary
                        if ( $useSubpages ) {
                                $link = Linker::normalizeSubpageLink(
                                        $this->getTitle(), $origLink, $text
                                );
                        } else {
                                $link = $origLink;
                        }

                        // \x7f isn't a default legal title char, so most likely strip
                        // markers will force us into the "invalid form" path above.  But,
                        // just in case, let's assert that xmlish tags aren't valid in
                        // the title position.
                        $unstrip = $this->mStripState->killMarkers( $link );
                        $noMarkers = ( $unstrip === $link );

                        $nt = $noMarkers ? Title::newFromText( $link ) : null;
                        if ( $nt === null ) {
                                $s .= $prefix . '[[' . $line;
                                continue;
                        }

                        $ns = $nt->getNamespace();
                        $iw = $nt->getInterwiki();

                        $noforce = ( substr( $origLink, 0, 1 ) !== ':' );

                        if ( $might_be_img ) { # if this is actually an invalid link
                                if ( $ns === NS_FILE && $noforce ) { # but might be an image
                                        $found = false;
                                        while ( true ) {
                                                # look at the next 'line' to see if we can close it there
                                                $a->next();
                                                $next_line = $a->current();
                                                if ( $next_line === false || $next_line === null ) {
                                                        break;
                                                }
                                                $m = explode( ']]', $next_line, 3 );
                                                if ( count( $m ) == 3 ) {
                                                        # the first ]] closes the inner link, the second the image
                                                        $found = true;
                                                        $text .= "[[{$m[0]}]]{$m[1]}";
                                                        $trail = $m[2];
                                                        break;
                                                } elseif ( count( $m ) == 2 ) {
                                                        # if there's exactly one ]] that's fine, we'll keep looking
                                                        $text .= "[[{$m[0]}]]{$m[1]}";
                                                } else {
                                                        # if $next_line is invalid too, we need look no further
                                                        $text .= '[[' . $next_line;
                                                        break;
                                                }
                                        }
                                        if ( !$found ) {
                                                # we couldn't find the end of this imageLink, so output it raw
                                                # but don't ignore what might be perfectly normal links in the text we've examined
                                                $holders->merge( $this->handleInternalLinks2( $text ) );
                                                $s .= "{$prefix}[[$link|$text";
                                                # note: no $trail, because without an end, there *is* no trail
                                                continue;
                                        }
                                } else { # it's not an image, so output it raw
                                        $s .= "{$prefix}[[$link|$text";
                                        # note: no $trail, because without an end, there *is* no trail
                                        continue;
                                }
                        }

                        $wasblank = ( $text == '' );
                        if ( $wasblank ) {
                                $text = $link;
                                if ( !$noforce ) {
                                        # Strip off leading ':'
                                        $text = substr( $text, 1 );
                                }
                        } else {
                                # T6598 madness. Handle the quotes only if they come from the alternate part
                                # [[Lista d''e paise d''o munno]] -> <a href="...">Lista d''e paise d''o munno</a>
                                # [[Criticism of Harry Potter|Criticism of ''Harry Potter'']]
                                #    -> <a href="Criticism of Harry Potter">Criticism of <i>Harry Potter</i></a>
                                $text = $this->doQuotes( $text );
                        }

                        # Link not escaped by : , create the various objects
                        if ( $noforce && !$nt->wasLocalInterwiki() ) {
                                # Interwikis
                                if (
                                        $iw && $this->mOptions->getInterwikiMagic() && $nottalk && (
                                                MediaWikiServices::getInstance()->getLanguageNameUtils()
                                                        ->getLanguageName(
                                                                $iw,
                                                                LanguageNameUtils::AUTONYMS,
                                                                LanguageNameUtils::DEFINED
                                                        )
                                                || in_array( $iw, $this->svcOptions->get( MainConfigNames::ExtraInterlanguageLinkPrefixes ) )
                                        )
                                ) {
                                        # T26502: filter duplicates
                                        if ( !isset( $this->mLangLinkLanguages[$iw] ) ) {
                                                $this->mLangLinkLanguages[$iw] = true;
                                                $this->mOutput->addLanguageLink( $nt->getFullText() );
                                        }

                                        /**
                                         * Strip the whitespace interwiki links produce, see T10897
                                         */
                                        $s = rtrim( $s . $prefix ) . $trail; # T175416
                                        continue;
                                }

                                if ( $ns === NS_FILE ) {
                                        if ( $wasblank ) {
                                                # if no parameters were passed, $text
                                                # becomes something like "File:Foo.png",
                                                # which we don't want to pass on to the
                                                # image generator
                                                $text = '';
                                        } else {
                                                # recursively parse links inside the image caption
                                                # actually, this will parse them in any other parameters, too,
                                                # but it might be hard to fix that, and it doesn't matter ATM
                                                $text = $this->handleExternalLinks( $text );
                                                $holders->merge( $this->handleInternalLinks2( $text ) );
                                        }
                                        # cloak any absolute URLs inside the image markup, so handleExternalLinks() won't touch them
                                        $s .= $prefix . $this->armorLinks(
                                                $this->makeImage( $nt, $text, $holders ) ) . $trail;
                                        continue;
                                } elseif ( $ns === NS_CATEGORY ) {
                                        /**
                                         * Strip the whitespace Category links produce, see T2087
                                         */
                                        $s = rtrim( $s . $prefix ) . $trail; # T2087, T87753

                                        if ( $wasblank ) {
                                                $sortkey = $this->mOutput->getPageProperty( 'defaultsort' ) ?? '';
                                        } else {
                                                $sortkey = $text;
                                        }
                                        $sortkey = Sanitizer::decodeCharReferences( $sortkey );
                                        $sortkey = str_replace( "\n", '', $sortkey );
                                        $sortkey = $this->getTargetLanguageConverter()->convertCategoryKey( $sortkey );
                                        $this->mOutput->addCategory( $nt->getDBkey(), $sortkey );

                                        continue;
                                }
                        }

                        # Self-link checking. For some languages, variants of the title are checked in
                        # LinkHolderArray::doVariants() to allow batching the existence checks necessary
                        # for linking to a different variant.
                        if ( $ns !== NS_SPECIAL && $nt->equals( $this->getTitle() ) ) {
                                $s .= $prefix . Linker::makeSelfLinkObj( $nt, $text, '', $trail, '',
                                        Sanitizer::escapeIdForLink( $nt->getFragment() ) );
                                continue;
                        }

                        # NS_MEDIA is a pseudo-namespace for linking directly to a file
                        # @todo FIXME: Should do batch file existence checks, see comment below
                        if ( $ns === NS_MEDIA ) {
                                # Give extensions a chance to select the file revision for us
                                $options = [];
                                $descQuery = false;
                                $this->hookRunner->onBeforeParserFetchFileAndTitle(
                                        // @phan-suppress-next-line PhanTypeMismatchArgument Type mismatch on pass-by-ref args
                                        $this, $nt, $options, $descQuery
                                );
                                # Fetch and register the file (file title may be different via hooks)
                                [ $file, $nt ] = $this->fetchFileAndTitle( $nt, $options );
                                # Cloak with NOPARSE to avoid replacement in handleExternalLinks
                                $s .= $prefix . $this->armorLinks(
                                        Linker::makeMediaLinkFile( $nt, $file, $text ) ) . $trail;
                                continue;
                        }

                        # Some titles, such as valid special pages or files in foreign repos, should
                        # be shown as bluelinks even though they're not included in the page table
                        # @todo FIXME: isAlwaysKnown() can be expensive for file links; we should really do
                        # batch file existence checks for NS_FILE and NS_MEDIA
                        if ( $iw == '' && $nt->isAlwaysKnown() ) {
                                $this->mOutput->addLink( $nt );
                                $s .= $this->makeKnownLinkHolder( $nt, $text, $trail, $prefix );
                        } else {
                                # Links will be added to the output link list after checking
                                $s .= $holders->makeHolder( $nt, $text, $trail, $prefix );
                        }
                }
                return $holders;
        }

        /**
         * Render a forced-blue link inline; protect against double expansion of
         * URLs if we're in a mode that prepends full URL prefixes to internal links.
         * Since this little disaster has to split off the trail text to avoid
         * breaking URLs in the following text without breaking trails on the
         * wiki links, it's been made into a horrible function.
         *
         * @param LinkTarget $nt
         * @param string $text
         * @param string $trail
         * @param string $prefix
         * @return string HTML-wikitext mix oh yuck
         */
        private function makeKnownLinkHolder( LinkTarget $nt, $text = '', $trail = '', $prefix = '' ) {
                [ $inside, $trail ] = Linker::splitTrail( $trail );

                if ( $text == '' ) {
                        $text = htmlspecialchars( $this->titleFormatter->getPrefixedText( $nt ) );
                }

                $link = $this->getLinkRenderer()->makeKnownLink(
                        $nt, new HtmlArmor( "$prefix$text$inside" )
                );

                return $this->armorLinks( $link ) . $trail;
        }

        /**
         * Insert a NOPARSE hacky thing into any inline links in a chunk that's
         * going to go through further parsing steps before inline URL expansion.
         *
         * Not needed quite as much as it used to be since free links are a bit
         * more sensible these days. But bracketed links are still an issue.
         *
         * @param string $text More-or-less HTML
         * @return string Less-or-more HTML with NOPARSE bits
         */
        private function armorLinks( $text ) {
                return preg_replace( '/\b((?i)' . $this->urlUtils->validProtocols() . ')/',
                        self::MARKER_PREFIX . "NOPARSE$1", $text );
        }

        /**
         * Make lists from lines starting with ':', '*', '#', etc. (DBL)
         *
         * @param string $text
         * @param bool $linestart Whether or not this is at the start of a line.
         * @internal
         * @return string The lists rendered as HTML
         * @deprecated since 1.35, will not be supported in future parsers
         */
        public function doBlockLevels( $text, $linestart ) {
                wfDeprecated( __METHOD__, '1.35' );
                return BlockLevelPass::doBlockLevels( $text, $linestart );
        }

        /**
         * Return value of a magic variable (like PAGENAME)
         *
         * @param string $index Magic variable identifier as mapped in MagicWordFactory::$mVariableIDs
         * @param PPFrame|false $frame
         *
         * @return string
         */
        private function expandMagicVariable( $index, $frame = false ) {
                /**
                 * Some of these require message or data lookups and can be
                 * expensive to check many times.
                 */
                if ( isset( $this->mVarCache[$index] ) ) {
                        return $this->mVarCache[$index];
                }

                $ts = new MWTimestamp( $this->mOptions->getTimestamp() /* TS_MW */ );
                if ( $this->hookContainer->isRegistered( 'ParserGetVariableValueTs' ) ) {
                        $s = $ts->getTimestamp( TS_UNIX );
                        $this->hookRunner->onParserGetVariableValueTs( $this, $s );
                        $ts = new MWTimestamp( $s );
                }

                $value = CoreMagicVariables::expand(
                        $this, $index, $ts, $this->svcOptions, $this->logger
                );

                if ( $value === null ) {
                        // Not a defined core magic word
                        // Don't give this hook unrestricted access to mVarCache
                        $fakeCache = [];
                        $this->hookRunner->onParserGetVariableValueSwitch(
                                // @phan-suppress-next-line PhanTypeMismatchArgument $value is passed as null but returned as string
                                $this, $fakeCache, $index, $value, $frame
                        );
                        // Cache the value returned by the hook by falling through here.
                        // Assert the the hook returned a non-null value for this MV
                        '@phan-var string $value';
                }

                $this->mVarCache[$index] = $value;

                return $value;
        }

        /**
         * Initialize the magic variables (like CURRENTMONTHNAME) and
         * substitution modifiers.
         */
        private function initializeVariables() {
                $variableIDs = $this->magicWordFactory->getVariableIDs();
                $substIDs = $this->magicWordFactory->getSubstIDs();

                $this->mVariables = $this->magicWordFactory->newArray( $variableIDs );
                $this->mSubstWords = $this->magicWordFactory->newArray( $substIDs );
        }

        /**
         * Get the document object model for the given wikitext
         *
         * @see Preprocessor::preprocessToObj()
         *
         * The generated DOM tree must depend only on the input text and the flags.
         * The DOM tree must be the same in OT_HTML and OT_WIKI mode, to avoid a
         * regression of T6899.
         *
         * Any flag added to the $flags parameter here, or any other parameter liable to cause a
         * change in the DOM tree for a given text, must be passed through the section identifier
         * in the section edit link and thus back to extractSections().
         *
         * @param string $text Wikitext
         * @param int $flags Bit field of Preprocessor::DOM_* constants
         * @return PPNode
         * @since 1.23 method is public
         */
        public function preprocessToDom( $text, $flags = 0 ) {
                return $this->getPreprocessor()->preprocessToObj( $text, $flags );
        }

        /**
         * Replace magic variables, templates, and template arguments
         * with the appropriate text. Templates are substituted recursively,
         * taking care to avoid infinite loops.
         *
         * Note that the substitution depends on value of $mOutputType:
         *  self::OT_WIKI: only {{subst:}} templates
         *  self::OT_PREPROCESS: templates but not extension tags
         *  self::OT_HTML: all templates and extension tags
         *
         * @param string $text The text to transform
         * @param false|PPFrame|array $frame Object describing the arguments passed to the
         *   template. Arguments may also be provided as an associative array, as
         *   was the usual case before MW1.12. Providing arguments this way may be
         *   useful for extensions wishing to perform variable replacement
         *   explicitly.
         * @param bool $argsOnly Only do argument (triple-brace) expansion, not
         *   double-brace expansion.
         * @return string
         * @since 1.24 method is public
         */
        public function replaceVariables( $text, $frame = false, $argsOnly = false ) {
                # Is there any text? Also, Prevent too big inclusions!
                $textSize = strlen( $text );
                if ( $textSize < 1 || $textSize > $this->mOptions->getMaxIncludeSize() ) {
                        return $text;
                }

                if ( $frame === false ) {
                        $frame = $this->getPreprocessor()->newFrame();
                } elseif ( !( $frame instanceof PPFrame ) ) {
                        $this->logger->debug(
                                __METHOD__ . " called using plain parameters instead of " .
                                "a PPFrame instance. Creating custom frame."
                        );
                        $frame = $this->getPreprocessor()->newCustomFrame( $frame );
                }

                $dom = $this->preprocessToDom( $text );
                $flags = $argsOnly ? PPFrame::NO_TEMPLATES : 0;
                $text = $frame->expand( $dom, $flags );

                return $text;
        }

        /**
         * Warn the user when a parser limitation is reached
         * Will warn at most once the user per limitation type
         *
         * The results are shown during preview and run through the Parser (See EditPage.php)
         *
         * @param string $limitationType Should be one of:
         *   'expensive-parserfunction' (corresponding messages:
         *       'expensive-parserfunction-warning',
         *       'expensive-parserfunction-category')
         *   'post-expand-template-argument' (corresponding messages:
         *       'post-expand-template-argument-warning',
         *       'post-expand-template-argument-category')
         *   'post-expand-template-inclusion' (corresponding messages:
         *       'post-expand-template-inclusion-warning',
         *       'post-expand-template-inclusion-category')
         *   'node-count-exceeded' (corresponding messages:
         *       'node-count-exceeded-warning',
         *       'node-count-exceeded-category')
         *   'expansion-depth-exceeded' (corresponding messages:
         *       'expansion-depth-exceeded-warning',
         *       'expansion-depth-exceeded-category')
         * @param string|int|null $current Current value
         * @param string|int|null $max Maximum allowed, when an explicit limit has been
         *       exceeded, provide the values (optional)
         * @internal
         */
        public function limitationWarn( $limitationType, $current = '', $max = '' ) {
                # does no harm if $current and $max are present but are unnecessary for the message
                # Not doing ->inLanguage( $this->mOptions->getUserLangObj() ), since this is shown
                # only during preview, and that would split the parser cache unnecessarily.
                $this->mOutput->addWarningMsg(
                        "$limitationType-warning",
                        Message::numParam( $current ),
                        Message::numParam( $max )
                );
                $this->addTrackingCategory( "$limitationType-category" );
        }

        /**
         * Return the text of a template, after recursively
         * replacing any variables or templates within the template.
         *
         * @param array $piece The parts of the template
         *   $piece['title']: the title, i.e. the part before the |
         *   $piece['parts']: the parameter array
         *   $piece['lineStart']: whether the brace was at the start of a line
         * @param PPFrame $frame The current frame, contains template arguments
         * @throws Exception
         * @return string|array The text of the template
         * @internal
         */
        public function braceSubstitution( array $piece, PPFrame $frame ) {
                // Flags

                // $text has been filled
                $found = false;
                $text = '';
                // wiki markup in $text should be escaped
                $nowiki = false;
                // $text is HTML, armour it against wikitext transformation
                $isHTML = false;
                // Force interwiki transclusion to be done in raw mode not rendered
                $forceRawInterwiki = false;
                // $text is a DOM node needing expansion in a child frame
                $isChildObj = false;
                // $text is a DOM node needing expansion in the current frame
                $isLocalObj = false;

                # Title object, where $text came from
                $title = false;

                # $part1 is the bit before the first |, and must contain only title characters.
                # Various prefixes will be stripped from it later.
                $titleWithSpaces = $frame->expand( $piece['title'] );
                $part1 = trim( $titleWithSpaces );
                $titleText = false;

                # Original title text preserved for various purposes
                $originalTitle = $part1;

                # $args is a list of argument nodes, starting from index 0, not including $part1
                # @todo FIXME: If piece['parts'] is null then the call to getLength()
                # below won't work b/c this $args isn't an object
                $args = ( $piece['parts'] == null ) ? [] : $piece['parts'];

                $profileSection = null; // profile templates

                $sawDeprecatedTemplateEquals = false; // T91154

                # SUBST
                // @phan-suppress-next-line PhanImpossibleCondition
                if ( !$found ) {
                        $substMatch = $this->mSubstWords->matchStartAndRemove( $part1 );
                        $part1 = trim( $part1 );

                        # Possibilities for substMatch: "subst", "safesubst" or FALSE
                        # Decide whether to expand template or keep wikitext as-is.
                        if ( $this->ot['wiki'] ) {
                                if ( $substMatch === false ) {
                                        $literal = true;  # literal when in PST with no prefix
                                } else {
                                        $literal = false; # expand when in PST with subst: or safesubst:
                                }
                        } else {
                                if ( $substMatch == 'subst' ) {
                                        $literal = true;  # literal when not in PST with plain subst:
                                } else {
                                        $literal = false; # expand when not in PST with safesubst: or no prefix
                                }
                        }
                        if ( $literal ) {
                                $text = $frame->virtualBracketedImplode( '{{', '|', '}}', $titleWithSpaces, $args );
                                $isLocalObj = true;
                                $found = true;
                        }
                }

                # Variables
                if ( !$found && $args->getLength() == 0 ) {
                        $id = $this->mVariables->matchStartToEnd( $part1 );
                        if ( $id !== false ) {
                                if ( strpos( $part1, ':' ) !== false ) {
                                        wfDeprecatedMsg(
                                                'Registering a magic variable with a name including a colon',
                                                '1.39', false, false
                                        );
                                }
                                $text = $this->expandMagicVariable( $id, $frame );
                                $found = true;
                        }
                }

                # MSG, MSGNW and RAW
                if ( !$found ) {
                        # Check for MSGNW:
                        $mwMsgnw = $this->magicWordFactory->get( 'msgnw' );
                        if ( $mwMsgnw->matchStartAndRemove( $part1 ) ) {
                                $nowiki = true;
                        } else {
                                # Remove obsolete MSG:
                                $mwMsg = $this->magicWordFactory->get( 'msg' );
                                $mwMsg->matchStartAndRemove( $part1 );
                        }

                        # Check for RAW:
                        $mwRaw = $this->magicWordFactory->get( 'raw' );
                        if ( $mwRaw->matchStartAndRemove( $part1 ) ) {
                                $forceRawInterwiki = true;
                        }
                }

                # Parser functions
                if ( !$found ) {
                        $colonPos = strpos( $part1, ':' );
                        if ( $colonPos !== false ) {
                                $func = substr( $part1, 0, $colonPos );
                                $funcArgs = [ trim( substr( $part1, $colonPos + 1 ) ) ];
                                $argsLength = $args->getLength();
                                for ( $i = 0; $i < $argsLength; $i++ ) {
                                        $funcArgs[] = $args->item( $i );
                                }

                                $result = $this->callParserFunction( $frame, $func, $funcArgs );

                                // Extract any forwarded flags
                                if ( isset( $result['title'] ) ) {
                                        $title = $result['title'];
                                }
                                if ( isset( $result['found'] ) ) {
                                        $found = $result['found'];
                                }
                                if ( array_key_exists( 'text', $result ) ) {
                                        // a string or null
                                        $text = $result['text'];
                                }
                                if ( isset( $result['nowiki'] ) ) {
                                        $nowiki = $result['nowiki'];
                                }
                                if ( isset( $result['isHTML'] ) ) {
                                        $isHTML = $result['isHTML'];
                                }
                                if ( isset( $result['forceRawInterwiki'] ) ) {
                                        $forceRawInterwiki = $result['forceRawInterwiki'];
                                }
                                if ( isset( $result['isChildObj'] ) ) {
                                        $isChildObj = $result['isChildObj'];
                                }
                                if ( isset( $result['isLocalObj'] ) ) {
                                        $isLocalObj = $result['isLocalObj'];
                                }
                        }
                }

                # Finish mangling title and then check for loops.
                # Set $title to a Title object and $titleText to the PDBK
                if ( !$found ) {
                        $ns = NS_TEMPLATE;
                        # Split the title into page and subpage
                        $subpage = '';
                        $relative = Linker::normalizeSubpageLink(
                                $this->getTitle(), $part1, $subpage
                        );
                        if ( $part1 !== $relative ) {
                                $part1 = $relative;
                                $ns = $this->getTitle()->getNamespace();
                        }
                        $title = Title::newFromText( $part1, $ns );
                        if ( $title ) {
                                $titleText = $title->getPrefixedText();
                                # Check for language variants if the template is not found
                                if ( $this->getTargetLanguageConverter()->hasVariants() && $title->getArticleID() == 0 ) {
                                        $this->getTargetLanguageConverter()->findVariantLink( $part1, $title, true );
                                }
                                # Do recursion depth check
                                $limit = $this->mOptions->getMaxTemplateDepth();
                                if ( $frame->depth >= $limit ) {
                                        $found = true;
                                        $text = '<span class="error">'
                                                . wfMessage( 'parser-template-recursion-depth-warning' )
                                                        ->numParams( $limit )->inContentLanguage()->text()
                                                . '</span>';
                                }
                        }
                }

                # Load from database
                if ( !$found && $title ) {
                        $profileSection = $this->mProfiler->scopedProfileIn( $title->getPrefixedDBkey() );
                        if ( !$title->isExternal() ) {
                                if ( $title->isSpecialPage()
                                        && $this->mOptions->getAllowSpecialInclusion()
                                        && $this->ot['html']
                                ) {
                                        $specialPage = $this->specialPageFactory->getPage( $title->getDBkey() );
                                        // Pass the template arguments as URL parameters.
                                        // "uselang" will have no effect since the Language object
                                        // is forced to the one defined in ParserOptions.
                                        $pageArgs = [];
                                        $argsLength = $args->getLength();
                                        for ( $i = 0; $i < $argsLength; $i++ ) {
                                                $bits = $args->item( $i )->splitArg();
                                                if ( strval( $bits['index'] ) === '' ) {
                                                        $name = trim( $frame->expand( $bits['name'], PPFrame::STRIP_COMMENTS ) );
                                                        $value = trim( $frame->expand( $bits['value'] ) );
                                                        $pageArgs[$name] = $value;
                                                }
                                        }

                                        // Create a new context to execute the special page
                                        $context = new RequestContext;
                                        $context->setTitle( $title );
                                        $context->setRequest( new FauxRequest( $pageArgs ) );
                                        if ( $specialPage && $specialPage->maxIncludeCacheTime() === 0 ) {
                                                $context->setUser( $this->userFactory->newFromUserIdentity( $this->getUserIdentity() ) );
                                        } else {
                                                // If this page is cached, then we better not be per user.
                                                $context->setUser( User::newFromName( '127.0.0.1', false ) );
                                        }
                                        $context->setLanguage( $this->mOptions->getUserLangObj() );
                                        $ret = $this->specialPageFactory->capturePath( $title, $context, $this->getLinkRenderer() );
                                        if ( $ret ) {
                                                $text = $context->getOutput()->getHTML();
                                                $this->mOutput->addOutputPageMetadata( $context->getOutput() );
                                                $found = true;
                                                $isHTML = true;
                                                if ( $specialPage && $specialPage->maxIncludeCacheTime() !== false ) {
                                                        $this->mOutput->updateRuntimeAdaptiveExpiry(
                                                                $specialPage->maxIncludeCacheTime()
                                                        );
                                                }
                                        }
                                } elseif ( $this->nsInfo->isNonincludable( $title->getNamespace() ) ) {
                                        $found = false; # access denied
                                        $this->logger->debug(
                                                __METHOD__ .
                                                ": template inclusion denied for " . $title->getPrefixedDBkey()
                                        );
                                } else {
                                        [ $text, $title ] = $this->getTemplateDom( $title );
                                        if ( $text !== false ) {
                                                $found = true;
                                                $isChildObj = true;
                                                if (
                                                        $title->getNamespace() === NS_TEMPLATE &&
                                                        $title->getDBkey() === '=' &&
                                                        $originalTitle === '='
                                                ) {
                                                        // Note that we won't get here if `=` is evaluated
                                                        // (in the future) as a parser function, nor if
                                                        // the Template namespace is given explicitly,
                                                        // ie `{{Template:=}}`.  Only `{{=}}` triggers.
                                                        $sawDeprecatedTemplateEquals = true; // T91154
                                                }
                                        }
                                }

                                # If the title is valid but undisplayable, make a link to it
                                if ( !$found && ( $this->ot['html'] || $this->ot['pre'] ) ) {
                                        $text = "[[:$titleText]]";
                                        $found = true;
                                }
                        } elseif ( $title->isTrans() ) {
                                # Interwiki transclusion
                                if ( $this->ot['html'] && !$forceRawInterwiki ) {
                                        $text = $this->interwikiTransclude( $title, 'render' );
                                        $isHTML = true;
                                } else {
                                        $text = $this->interwikiTransclude( $title, 'raw' );
                                        # Preprocess it like a template
                                        $text = $this->preprocessToDom( $text, Preprocessor::DOM_FOR_INCLUSION );
                                        $isChildObj = true;
                                }
                                $found = true;
                        }

                        # Do infinite loop check
                        # This has to be done after redirect resolution to avoid infinite loops via redirects
                        if ( !$frame->loopCheck( $title ) ) {
                                $found = true;
                                $text = '<span class="error">'
                                        . wfMessage( 'parser-template-loop-warning', $titleText )->inContentLanguage()->text()
                                        . '</span>';
                                $this->addTrackingCategory( 'template-loop-category' );
                                $this->mOutput->addWarningMsg(
                                        'template-loop-warning',
                                        Message::plaintextParam( $titleText )
                                );
                                $this->logger->debug( __METHOD__ . ": template loop broken at '$titleText'" );
                        }
                }

                # If we haven't found text to substitute by now, we're done
                # Recover the source wikitext and return it
                if ( !$found ) {
                        $text = $frame->virtualBracketedImplode( '{{', '|', '}}', $titleWithSpaces, $args );
                        if ( $profileSection ) {
                                $this->mProfiler->scopedProfileOut( $profileSection );
                        }
                        return [ 'object' => $text ];
                }

                # Expand DOM-style return values in a child frame
                if ( $isChildObj ) {
                        # Clean up argument array
                        $newFrame = $frame->newChild( $args, $title );

                        if ( $nowiki ) {
                                $text = $newFrame->expand( $text, PPFrame::RECOVER_ORIG );
                        } elseif ( $titleText !== false && $newFrame->isEmpty() ) {
                                # Expansion is eligible for the empty-frame cache
                                $text = $newFrame->cachedExpand( $titleText, $text );
                        } else {
                                # Uncached expansion
                                $text = $newFrame->expand( $text );
                        }
                }
                if ( $isLocalObj && $nowiki ) {
                        $text = $frame->expand( $text, PPFrame::RECOVER_ORIG );
                        $isLocalObj = false;
                }

                if ( $profileSection ) {
                        $this->mProfiler->scopedProfileOut( $profileSection );
                }
                if (
                        $sawDeprecatedTemplateEquals &&
                        $this->mStripState->unstripBoth( $text ) !== '='
                ) {
                        // T91154: {{=}} is deprecated when it doesn't expand to `=`;
                        // use {{Template:=}} if you must.
                        $this->addTrackingCategory( 'template-equals-category' );
                        $this->mOutput->addWarningMsg( 'template-equals-warning' );
                }

                # Replace raw HTML by a placeholder
                if ( $isHTML ) {
                        $text = $this->insertStripItem( $text );
                } elseif ( $nowiki && ( $this->ot['html'] || $this->ot['pre'] ) ) {
                        # Escape nowiki-style return values
                        $text = wfEscapeWikiText( $text );
                } elseif ( is_string( $text )
                        && !$piece['lineStart']
                        && preg_match( '/^(?:{\\||:|;|#|\*)/', $text )
                ) {
                        # T2529: if the template begins with a table or block-level
                        # element, it should be treated as beginning a new line.
                        # This behavior is somewhat controversial.
                        $text = "\n" . $text;
                }

                if ( is_string( $text ) && !$this->incrementIncludeSize( 'post-expand', strlen( $text ) ) ) {
                        # Error, oversize inclusion
                        if ( $titleText !== false ) {
                                # Make a working, properly escaped link if possible (T25588)
                                $text = "[[:$titleText]]";
                        } else {
                                # This will probably not be a working link, but at least it may
                                # provide some hint of where the problem is
                                $originalTitle = preg_replace( '/^:/', '', $originalTitle );
                                $text = "[[:$originalTitle]]";
                        }
                        $text .= $this->insertStripItem( '<!-- WARNING: template omitted, '
                                . 'post-expand include size too large -->' );
                        $this->limitationWarn( 'post-expand-template-inclusion' );
                }

                if ( $isLocalObj ) {
                        $ret = [ 'object' => $text ];
                } else {
                        $ret = [ 'text' => $text ];
                }

                return $ret;
        }

        /**
         * Call a parser function and return an array with text and flags.
         *
         * The returned array will always contain a boolean 'found', indicating
         * whether the parser function was found or not. It may also contain the
         * following:
         *  text: string|object, resulting wikitext or PP DOM object
         *  isHTML: bool, $text is HTML, armour it against wikitext transformation
         *  isChildObj: bool, $text is a DOM node needing expansion in a child frame
         *  isLocalObj: bool, $text is a DOM node needing expansion in the current frame
         *  nowiki: bool, wiki markup in $text should be escaped
         *
         * @since 1.21
         * @param PPFrame $frame The current frame, contains template arguments
         * @param string $function Function name
         * @param array $args Arguments to the function
         * @return array
         */
        public function callParserFunction( PPFrame $frame, $function, array $args = [] ) {
                # Case sensitive functions
                if ( isset( $this->mFunctionSynonyms[1][$function] ) ) {
                        $function = $this->mFunctionSynonyms[1][$function];
                } else {
                        # Case insensitive functions
                        $function = $this->contLang->lc( $function );
                        if ( isset( $this->mFunctionSynonyms[0][$function] ) ) {
                                $function = $this->mFunctionSynonyms[0][$function];
                        } else {
                                return [ 'found' => false ];
                        }
                }

                [ $callback, $flags ] = $this->mFunctionHooks[$function];

                $allArgs = [ $this ];
                if ( $flags & self::SFH_OBJECT_ARGS ) {
                        # Convert arguments to PPNodes and collect for appending to $allArgs
                        $funcArgs = [];
                        foreach ( $args as $k => $v ) {
                                if ( $v instanceof PPNode || $k === 0 ) {
                                        $funcArgs[] = $v;
                                } else {
                                        $funcArgs[] = $this->mPreprocessor->newPartNodeArray( [ $k => $v ] )->item( 0 );
                                }
                        }

                        # Add a frame parameter, and pass the arguments as an array
                        $allArgs[] = $frame;
                        $allArgs[] = $funcArgs;
                } else {
                        # Convert arguments to plain text and append to $allArgs
                        foreach ( $args as $k => $v ) {
                                if ( $v instanceof PPNode ) {
                                        $allArgs[] = trim( $frame->expand( $v ) );
                                } elseif ( is_int( $k ) && $k >= 0 ) {
                                        $allArgs[] = trim( $v );
                                } else {
                                        $allArgs[] = trim( "$k=$v" );
                                }
                        }
                }

                $result = $callback( ...$allArgs );

                # The interface for function hooks allows them to return a wikitext
                # string or an array containing the string and any flags. This mungs
                # things around to match what this method should return.
                if ( !is_array( $result ) ) {
                        $result = [
                                'found' => true,
                                'text' => $result,
                        ];
                } else {
                        if ( isset( $result[0] ) && !isset( $result['text'] ) ) {
                                $result['text'] = $result[0];
                        }
                        unset( $result[0] );
                        $result += [
                                'found' => true,
                        ];
                }

                $noparse = true;
                $preprocessFlags = 0;
                if ( isset( $result['noparse'] ) ) {
                        $noparse = $result['noparse'];
                }
                if ( isset( $result['preprocessFlags'] ) ) {
                        $preprocessFlags = $result['preprocessFlags'];
                }

                if ( !$noparse ) {
                        $result['text'] = $this->preprocessToDom( $result['text'], $preprocessFlags );
                        $result['isChildObj'] = true;
                }

                return $result;
        }

        /**
         * Get the semi-parsed DOM representation of a template with a given title,
         * and its redirect destination title. Cached.
         *
         * @param LinkTarget $title
         *
         * @return array
         * @since 1.12
         */
        public function getTemplateDom( LinkTarget $title ) {
                $cacheTitle = $title;
                $titleKey = CacheKeyHelper::getKeyForPage( $title );

                if ( isset( $this->mTplRedirCache[$titleKey] ) ) {
                        [ $ns, $dbk ] = $this->mTplRedirCache[$titleKey];
                        $title = Title::makeTitle( $ns, $dbk );
                        $titleKey = CacheKeyHelper::getKeyForPage( $title );
                }
                if ( isset( $this->mTplDomCache[$titleKey] ) ) {
                        return [ $this->mTplDomCache[$titleKey], $title ];
                }

                # Cache miss, go to the database
                [ $text, $title ] = $this->fetchTemplateAndTitle( $title );

                if ( $text === false ) {
                        $this->mTplDomCache[$titleKey] = false;
                        return [ false, $title ];
                }

                $dom = $this->preprocessToDom( $text, Preprocessor::DOM_FOR_INCLUSION );
                $this->mTplDomCache[$titleKey] = $dom;

                if ( !$title->isSamePageAs( $cacheTitle ) ) {
                        $this->mTplRedirCache[ CacheKeyHelper::getKeyForPage( $cacheTitle ) ] =
                                [ $title->getNamespace(), $title->getDBkey() ];
                }

                return [ $dom, $title ];
        }

        /**
         * Fetch the current revision of a given title as a RevisionRecord.
         * Note that the revision (and even the title) may not exist in the database,
         * so everything contributing to the output of the parser should use this method
         * where possible, rather than getting the revisions themselves. This
         * method also caches its results, so using it benefits performance.
         *
         * This can return null if the callback returns false
         *
         * @since 1.35
         * @param LinkTarget $link
         * @return RevisionRecord|null
         */
        public function fetchCurrentRevisionRecordOfTitle( LinkTarget $link ) {
                $cacheKey = CacheKeyHelper::getKeyForPage( $link );
                if ( !$this->currentRevisionCache ) {
                        $this->currentRevisionCache = new MapCacheLRU( 100 );
                }
                if ( !$this->currentRevisionCache->has( $cacheKey ) ) {
                        $title = Title::newFromLinkTarget( $link ); // hook signature compat
                        $revisionRecord =
                                // Defaults to Parser::statelessFetchRevisionRecord()
                                call_user_func(
                                        $this->mOptions->getCurrentRevisionRecordCallback(),
                                        $title,
                                        $this
                                );
                        if ( $revisionRecord === false ) {
                                // Parser::statelessFetchRevisionRecord() can return false;
                                // normalize it to null.
                                $revisionRecord = null;
                        }
                        $this->currentRevisionCache->set( $cacheKey, $revisionRecord );
                }
                return $this->currentRevisionCache->get( $cacheKey );
        }

        /**
         * @param LinkTarget $link
         * @return bool
         * @since 1.34
         * @internal
         */
        public function isCurrentRevisionOfTitleCached( LinkTarget $link ) {
                $key = CacheKeyHelper::getKeyForPage( $link );
                return (
                        $this->currentRevisionCache &&
                        $this->currentRevisionCache->has( $key )
                );
        }

        /**
         * Wrapper around RevisionLookup::getKnownCurrentRevision
         *
         * @since 1.34
         * @param LinkTarget $link
         * @param Parser|null $parser
         * @return RevisionRecord|false False if missing
         */
        public static function statelessFetchRevisionRecord( LinkTarget $link, $parser = null ) {
                if ( $link instanceof PageIdentity ) {
                        // probably a Title, just use it.
                        $page = $link;
                } else {
                        // XXX: use RevisionStore::getPageForLink()!
                        //      ...but get the info for the current revision at the same time?
                        //      Should RevisionStore::getKnownCurrentRevision accept a LinkTarget?
                        $page = Title::newFromLinkTarget( $link );
                }

                $revRecord = MediaWikiServices::getInstance()
                        ->getRevisionLookup()
                        ->getKnownCurrentRevision( $page );
                return $revRecord;
        }

        /**
         * Fetch the unparsed text of a template and register a reference to it.
         * @param LinkTarget $link
         * @return array ( string or false, Title )
         * @since 1.11
         */
        public function fetchTemplateAndTitle( LinkTarget $link ) {
                // Use Title for compatibility with callbacks and return type
                $title = Title::newFromLinkTarget( $link );

                // Defaults to Parser::statelessFetchTemplate()
                $templateCb = $this->mOptions->getTemplateCallback();
                $stuff = $templateCb( $title, $this );
                $revRecord = $stuff['revision-record'] ?? null;

                $text = $stuff['text'];
                if ( is_string( $stuff['text'] ) ) {
                        // We use U+007F DELETE to distinguish strip markers from regular text
                        $text = strtr( $text, "\x7f", "?" );
                }
                $finalTitle = $stuff['finalTitle'] ?? $title;
                foreach ( ( $stuff['deps'] ?? [] ) as $dep ) {
                        $this->mOutput->addTemplate( $dep['title'], $dep['page_id'], $dep['rev_id'] );
                        if ( $dep['title']->equals( $this->getTitle() ) && $revRecord instanceof RevisionRecord ) {
                                // Self-transclusion; final result may change based on the new page version
                                try {
                                        $sha1 = $revRecord->getSha1();
                                } catch ( RevisionAccessException $e ) {
                                        $sha1 = null;
                                }
                                $this->setOutputFlag( ParserOutputFlags::VARY_REVISION_SHA1, 'Self transclusion' );
                                $this->getOutput()->setRevisionUsedSha1Base36( $sha1 );
                        }
                }

                return [ $text, $finalTitle ];
        }

        /**
         * Static function to get a template
         * Can be overridden via ParserOptions::setTemplateCallback().
         *
         * @param LinkTarget $page
         * @param Parser|false $parser
         *
         * @return array
         * @since 1.12
         */
        public static function statelessFetchTemplate( $page, $parser = false ) {
                $title = Title::castFromLinkTarget( $page ); // for compatibility with return type
                $text = $skip = false;
                $finalTitle = $title;
                $deps = [];
                $revRecord = null;
                $contextTitle = $parser ? $parser->getTitle() : null;

                $services = MediaWikiServices::getInstance();
                # Loop to fetch the article, with up to 2 redirects
                $revLookup = $services->getRevisionLookup();
                $hookRunner = new HookRunner( $services->getHookContainer() );
                for ( $i = 0; $i < 3 && is_object( $title ); $i++ ) {
                        # Give extensions a chance to select the revision instead
                        $revRecord = null; # Assume no hook
                        $id = false; # Assume current
                        $origTitle = $title;
                        $titleChanged = false;
                        $hookRunner->onBeforeParserFetchTemplateRevisionRecord(
                                # The $title is a not a PageIdentity, as it may
                                # contain fragments or even represent an attempt to transclude
                                # a broken or otherwise-missing Title, which the hook may
                                # fix up.  Similarly, the $contextTitle may represent a special
                                # page or other page which "exists" as a parsing context but
                                # is not in the DB.
                                $contextTitle, $title,
                                $skip, $revRecord
                        );

                        if ( $skip ) {
                                $text = false;
                                $deps[] = [
                                        'title' => $title,
                                        'page_id' => $title->getArticleID(),
                                        'rev_id' => null
                                ];
                                break;
                        }
                        # Get the revision
                        if ( !$revRecord ) {
                                if ( $id ) {
                                        # Handle $id returned by deprecated legacy hook
                                        $revRecord = $revLookup->getRevisionById( $id );
                                } elseif ( $parser ) {
                                        $revRecord = $parser->fetchCurrentRevisionRecordOfTitle( $title );
                                } else {
                                        $revRecord = $revLookup->getRevisionByTitle( $title );
                                }
                        }
                        if ( $revRecord ) {
                                # Update title, as $revRecord may have been changed by hook
                                $title = Title::newFromLinkTarget(
                                        $revRecord->getPageAsLinkTarget()
                                );
                                $deps[] = [
                                        'title' => $title,
                                        'page_id' => $revRecord->getPageId(),
                                        'rev_id' => $revRecord->getId(),
                                ];
                        } else {
                                $deps[] = [
                                        'title' => $title,
                                        'page_id' => $title->getArticleID(),
                                        'rev_id' => null,
                                ];
                        }
                        if ( !$title->equals( $origTitle ) ) {
                                # If we fetched a rev from a different title, register
                                # the original title too...
                                $deps[] = [
                                        'title' => $origTitle,
                                        'page_id' => $origTitle->getArticleID(),
                                        'rev_id' => null,
                                ];
                                $titleChanged = true;
                        }
                        # If there is no current revision, there is no page
                        if ( $revRecord === null || $revRecord->getId() === null ) {
                                $linkCache = $services->getLinkCache();
                                $linkCache->addBadLinkObj( $title );
                        }
                        if ( $revRecord ) {
                                if ( $titleChanged && !$revRecord->hasSlot( SlotRecord::MAIN ) ) {
                                        // We've added this (missing) title to the dependencies;
                                        // give the hook another chance to redirect it to an
                                        // actual page.
                                        $text = false;
                                        $finalTitle = $title;
                                        continue;
                                }
                                if ( $revRecord->hasSlot( SlotRecord::MAIN ) ) { // T276476
                                        $content = $revRecord->getContent( SlotRecord::MAIN );
                                        $text = $content ? $content->getWikitextForTransclusion() : null;
                                } else {
                                        $text = false;
                                }

                                if ( $text === false || $text === null ) {
                                        $text = false;
                                        break;
                                }
                        } elseif ( $title->getNamespace() === NS_MEDIAWIKI ) {
                                $message = wfMessage( $services->getContentLanguage()->
                                        lcfirst( $title->getText() ) )->inContentLanguage();
                                if ( !$message->exists() ) {
                                        $text = false;
                                        break;
                                }
                                $text = $message->plain();
                                break;
                        } else {
                                break;
                        }
                        // @phan-suppress-next-line PhanPossiblyUndeclaredVariable Only reached when content is set
                        if ( !$content ) {
                                break;
                        }
                        # Redirect?
                        $finalTitle = $title;
                        $title = $content->getRedirectTarget();
                }

                $retValues = [
                        // previously, when this also returned a Revision object, we set
                        // 'revision-record' to false instead of null if it was unavailable,
                        // so that callers to use isset and then rely on the revision-record
                        // key instead of the revision key, even if there was no corresponding
                        // object - we continue to set to false here for backwards compatability
                        'revision-record' => $revRecord ?: false,
                        'text' => $text,
                        'finalTitle' => $finalTitle,
                        'deps' => $deps
                ];
                return $retValues;
        }

        /**
         * Fetch a file and its title and register a reference to it.
         * If 'broken' is a key in $options then the file will appear as a broken thumbnail.
         * @param LinkTarget $link
         * @param array $options Array of options to RepoGroup::findFile
         * @return array ( File or false, Title of file )
         * @since 1.18
         */
        public function fetchFileAndTitle( LinkTarget $link, array $options = [] ) {
                $file = $this->fetchFileNoRegister( $link, $options );

                $time = $file ? $file->getTimestamp() : false;
                $sha1 = $file ? $file->getSha1() : false;
                # Register the file as a dependency...
                $this->mOutput->addImage( $link->getDBkey(), $time, $sha1 );
                if ( $file && !$link->isSameLinkAs( $file->getTitle() ) ) {
                        # Update fetched file title after resolving redirects, etc.
                        $link = $file->getTitle();
                        $this->mOutput->addImage( $link->getDBkey(), $time, $sha1 );
                }

                $title = Title::newFromLinkTarget( $link ); // for return type compat
                return [ $file, $title ];
        }

        /**
         * Helper function for fetchFileAndTitle.
         *
         * Also useful if you need to fetch a file but not use it yet,
         * for example to get the file's handler.
         *
         * @param LinkTarget $link
         * @param array $options Array of options to RepoGroup::findFile
         * @return File|false
         */
        protected function fetchFileNoRegister( LinkTarget $link, array $options = [] ) {
                if ( isset( $options['broken'] ) ) {
                        $file = false; // broken thumbnail forced by hook
                } else {
                        $repoGroup = MediaWikiServices::getInstance()->getRepoGroup();
                        if ( isset( $options['sha1'] ) ) { // get by (sha1,timestamp)
                                $file = $repoGroup->findFileFromKey( $options['sha1'], $options );
                        } else { // get by (name,timestamp)
                                $file = $repoGroup->findFile( $link, $options );
                        }
                }
                return $file;
        }

        /**
         * Transclude an interwiki link.
         *
         * @param LinkTarget $link
         * @param string $action Usually one of (raw, render)
         *
         * @return string
         * @internal
         */
        public function interwikiTransclude( LinkTarget $link, $action ) {
                if ( !$this->svcOptions->get( MainConfigNames::EnableScaryTranscluding ) ) {
                        return wfMessage( 'scarytranscludedisabled' )->inContentLanguage()->text();
                }

                // TODO: extract relevant functionality from Title
                $title = Title::newFromLinkTarget( $link );

                $url = $title->getFullURL( [ 'action' => $action ] );
                if ( strlen( $url ) > 1024 ) {
                        return wfMessage( 'scarytranscludetoolong' )->inContentLanguage()->text();
                }

                $wikiId = $title->getTransWikiID(); // remote wiki ID or false

                $fname = __METHOD__;

                $cache = $this->wanCache;
                $data = $cache->getWithSetCallback(
                        $cache->makeGlobalKey(
                                'interwiki-transclude',
                                ( $wikiId !== false ) ? $wikiId : 'external',
                                sha1( $url )
                        ),
                        $this->svcOptions->get( MainConfigNames::TranscludeCacheExpiry ),
                        function ( $oldValue, &$ttl ) use ( $url, $fname, $cache ) {
                                $req = $this->httpRequestFactory->create( $url, [], $fname );

                                $status = $req->execute(); // Status object
                                if ( !$status->isOK() ) {
                                        $ttl = $cache::TTL_UNCACHEABLE;
                                } elseif ( $req->getResponseHeader( 'X-Database-Lagged' ) !== null ) {
                                        $ttl = min( $cache::TTL_LAGGED, $ttl );
                                }

                                return [
                                        'text' => $status->isOK() ? $req->getContent() : null,
                                        'code' => $req->getStatus()
                                ];
                        },
                        [
                                'checkKeys' => ( $wikiId !== false )
                                        ? [ $cache->makeGlobalKey( 'interwiki-page', $wikiId, $title->getDBkey() ) ]
                                        : [],
                                'pcGroup' => 'interwiki-transclude:5',
                                'pcTTL' => $cache::TTL_PROC_LONG
                        ]
                );

                if ( is_string( $data['text'] ) ) {
                        $text = $data['text'];
                } elseif ( $data['code'] != 200 ) {
                        // Though we failed to fetch the content, this status is useless.
                        $text = wfMessage( 'scarytranscludefailed-httpstatus' )
                                ->params( $url, $data['code'] )->inContentLanguage()->text();
                } else {
                        $text = wfMessage( 'scarytranscludefailed', $url )->inContentLanguage()->text();
                }

                return $text;
        }

        /**
         * Triple brace replacement -- used for template arguments
         * @internal
         *
         * @param array $piece
         * @param PPFrame $frame
         *
         * @return array
         * @internal
         */
        public function argSubstitution( array $piece, PPFrame $frame ) {
                $error = false;
                $parts = $piece['parts'];
                $nameWithSpaces = $frame->expand( $piece['title'] );
                $argName = trim( $nameWithSpaces );
                $object = false;
                $text = $frame->getArgument( $argName );
                if ( $text === false && $parts->getLength() > 0
                        && ( $this->ot['html']
                                || $this->ot['pre']
                                || ( $this->ot['wiki'] && $frame->isTemplate() )
                        )
                ) {
                        # No match in frame, use the supplied default
                        $object = $parts->item( 0 )->getChildren();
                }
                if ( !$this->incrementIncludeSize( 'arg', strlen( $text ) ) ) {
                        $error = '<!-- WARNING: argument omitted, expansion size too large -->';
                        $this->limitationWarn( 'post-expand-template-argument' );
                }

                if ( $text === false && $object === false ) {
                        # No match anywhere
                        $object = $frame->virtualBracketedImplode( '{{{', '|', '}}}', $nameWithSpaces, $parts );
                }
                if ( $error !== false ) {
                        $text .= $error;
                }
                if ( $object !== false ) {
                        $ret = [ 'object' => $object ];
                } else {
                        $ret = [ 'text' => $text ];
                }

                return $ret;
        }

        /**
         * @param string $lowerTagName
         * @return bool
         */
        public function tagNeedsNowikiStrippedInTagPF( string $lowerTagName ): bool {
                $parsoidSiteConfig = MediaWikiServices::getInstance()->getParsoidSiteConfig();
                return $parsoidSiteConfig->tagNeedsNowikiStrippedInTagPF( $lowerTagName );
        }

        /**
         * Return the text to be used for a given extension tag.
         * This is the ghost of strip().
         *
         * @param array $params Associative array of parameters:
         *     name       PPNode for the tag name
         *     attr       PPNode for unparsed text where tag attributes are thought to be
         *     attributes Optional associative array of parsed attributes
         *     inner      Contents of extension element
         *     noClose    Original text did not have a close tag
         * @param PPFrame $frame
         * @param bool $processNowiki Process nowiki tags by running the nowiki tag handler
         *     Normally, nowikis are only processed for the HTML output type. With this
         *     arg set to true, they are processed (and converted to a nowiki strip marker)
         *     for all output types.
         * @return string
         * @internal
         * @since 1.12
         */
        public function extensionSubstitution( array $params, PPFrame $frame, bool $processNowiki = false ) {
                static $errorStr = '<span class="error">';

                $name = $frame->expand( $params['name'] );
                if ( str_starts_with( $name, $errorStr ) ) {
                        // Probably expansion depth or node count exceeded. Just punt the
                        // error up.
                        return $name;
                }

                // Parse attributes from XML-like wikitext syntax
                $attrText = !isset( $params['attr'] ) ? '' : $frame->expand( $params['attr'] );
                if ( str_starts_with( $attrText, $errorStr ) ) {
                        // See above
                        return $attrText;
                }

                // We can't safely check if the expansion for $content resulted in an
                // error, because the content could happen to be the error string
                // (T149622).
                $content = !isset( $params['inner'] ) ? null : $frame->expand( $params['inner'] );

                $marker = self::MARKER_PREFIX . "-$name-"
                        . sprintf( '%08X', $this->mMarkerIndex++ ) . self::MARKER_SUFFIX;

                $normalizedName = strtolower( $name );
                $isNowiki = $normalizedName === 'nowiki';
                $markerType = $isNowiki ? 'nowiki' : 'general';
                if ( $this->ot['html'] || ( $processNowiki && $isNowiki ) ) {
                        $attributes = Sanitizer::decodeTagAttributes( $attrText );
                        // Merge in attributes passed via {{#tag:}} parser function
                        if ( isset( $params['attributes'] ) ) {
                                $attributes += $params['attributes'];
                        }

                        if ( isset( $this->mTagHooks[$normalizedName] ) ) {
                                // Note that $content may be null here, for example if the
                                // tag is self-closed.
                                $output = call_user_func_array( $this->mTagHooks[$normalizedName],
                                        [ $content, $attributes, $this, $frame ] );
                        } else {
                                $output = '<span class="error">Invalid tag extension name: ' .
                                        htmlspecialchars( $normalizedName ) . '</span>';
                        }

                        if ( is_array( $output ) ) {
                                // Extract flags
                                $flags = $output;
                                $output = $flags[0];
                                if ( isset( $flags['markerType'] ) ) {
                                        $markerType = $flags['markerType'];
                                }
                        }
                } else {
                        // We're substituting a {{subst:#tag:}} parser function.
                        // Convert the attributes it passed into the XML-like string.
                        if ( isset( $params['attributes'] ) ) {
                                foreach ( $params['attributes'] as $attrName => $attrValue ) {
                                        $attrText .= ' ' . htmlspecialchars( $attrName ) . '="' .
                                                htmlspecialchars( $attrValue, ENT_COMPAT ) . '"';
                                }
                        }
                        if ( $content === null ) {
                                $output = "<$name$attrText/>";
                        } else {
                                $close = $params['close'] === null ? '' : $frame->expand( $params['close'] );
                                if ( str_starts_with( $close, $errorStr ) ) {
                                        // See above
                                        return $close;
                                }
                                $output = "<$name$attrText>$content$close";
                        }
                }

                if ( $markerType === 'none' ) {
                        return $output;
                } elseif ( $markerType === 'nowiki' ) {
                        $this->mStripState->addNoWiki( $marker, $output );
                } elseif ( $markerType === 'general' ) {
                        $this->mStripState->addGeneral( $marker, $output );
                } else {
                        throw new UnexpectedValueException( __METHOD__ . ': invalid marker type' );
                }
                return $marker;
        }

        /**
         * Increment an include size counter
         *
         * @param string $type The type of expansion
         * @param int $size The size of the text
         * @return bool False if this inclusion would take it over the maximum, true otherwise
         */
        private function incrementIncludeSize( $type, $size ) {
                if ( $this->mIncludeSizes[$type] + $size > $this->mOptions->getMaxIncludeSize() ) {
                        return false;
                } else {
                        $this->mIncludeSizes[$type] += $size;
                        return true;
                }
        }

        /**
         * @return bool False if the limit has been exceeded
         * @since 1.13
         */
        public function incrementExpensiveFunctionCount() {
                $this->mExpensiveFunctionCount++;
                return $this->mExpensiveFunctionCount <= $this->mOptions->getExpensiveParserFunctionLimit();
        }

        /**
         * Strip double-underscore items like __NOGALLERY__ and __NOTOC__
         * Fills $this->mDoubleUnderscores, returns the modified text
         *
         * @param string $text
         * @return string
         */
        private function handleDoubleUnderscore( $text ) {
                # The position of __TOC__ needs to be recorded
                $mw = $this->magicWordFactory->get( 'toc' );
                if ( $mw->match( $text ) ) {
                        $this->mShowToc = true;
                        $this->mForceTocPosition = true;

                        # Set a placeholder. At the end we'll fill it in with the TOC.
                        $text = $mw->replace( self::TOC_PLACEHOLDER, $text, 1 );

                        # Only keep the first one.
                        $text = $mw->replace( '', $text );
                        # For consistency with all other double-underscores
                        # (see below)
                        $this->mOutput->setPageProperty( 'toc', '' );
                }

                # Now match and remove the rest of them
                $mwa = $this->magicWordFactory->getDoubleUnderscoreArray();
                $this->mDoubleUnderscores = $mwa->matchAndRemove( $text );

                if ( isset( $this->mDoubleUnderscores['nogallery'] ) ) {
                        $this->mOutput->setNoGallery( true );
                }
                if ( isset( $this->mDoubleUnderscores['notoc'] ) && !$this->mForceTocPosition ) {
                        $this->mShowToc = false;
                }
                if ( isset( $this->mDoubleUnderscores['hiddencat'] )
                        && $this->getTitle()->getNamespace() === NS_CATEGORY
                ) {
                        $this->addTrackingCategory( 'hidden-category-category' );
                }
                # (T10068) Allow control over whether robots index a page.
                # __INDEX__ always overrides __NOINDEX__, see T16899
                if ( isset( $this->mDoubleUnderscores['noindex'] ) && $this->getTitle()->canUseNoindex() ) {
                        $this->mOutput->setIndexPolicy( 'noindex' );
                        $this->addTrackingCategory( 'noindex-category' );
                }
                if ( isset( $this->mDoubleUnderscores['index'] ) && $this->getTitle()->canUseNoindex() ) {
                        $this->mOutput->setIndexPolicy( 'index' );
                        $this->addTrackingCategory( 'index-category' );
                }

                # Cache all double underscores in the database
                foreach ( $this->mDoubleUnderscores as $key => $val ) {
                        $this->mOutput->setPageProperty( $key, '' );
                }

                return $text;
        }

        /**
         * @see TrackingCategories::addTrackingCategory()
         * @param string $msg Message key
         * @return bool Whether the addition was successful
         * @since 1.19 method is public
         */
        public function addTrackingCategory( $msg ) {
                return $this->trackingCategories->addTrackingCategory(
                        $this->mOutput, $msg, $this->getPage()
                );
        }

        /**
         * Helper function to correctly set the target language and title of
         * a message based on the parser context. Most uses of system messages
         * inside extensions or parser functions should use this method (instead
         * of directly using `wfMessage`) to ensure that the cache is not
         * polluted.
         *
         * @param string $msg The localization message key
         * @param mixed ...$args Optional arguments for the message
         * @return Message
         * @since 1.40
         * @see https://phabricator.wikimedia.org/T202481
         */
        public function msg( string $msg, ...$args ): Message {
                return wfMessage( $msg, ...$args )
                        ->inLanguage( $this->getTargetLanguage() )
                        ->page( $this->getPage() );
        }

        /**
         * This function accomplishes several tasks:
         * 1) Auto-number headings if that option is enabled
         * 2) Add an [edit] link to sections for users who have enabled the option and can edit the page
         * 3) Add a Table of contents on the top for users who have enabled the option
         * 4) Auto-anchor headings
         *
         * It loops through all headlines, collects the necessary data, then splits up the
         * string and re-inserts the newly formatted headlines.
         *
         * @param string $text
         * @param string $origText Original, untouched wikitext
         * @param bool $isMain
         * @return string
         */
        private function finalizeHeadings( $text, $origText, $isMain = true ) {
                # Inhibit editsection links if requested in the page
                if ( isset( $this->mDoubleUnderscores['noeditsection'] ) ) {
                        $maybeShowEditLink = false;
                } else {
                        $maybeShowEditLink = true; /* Actual presence will depend on post-cache transforms */
                }

                # Get all headlines for numbering them and adding funky stuff like [edit]
                # links - this is for later, but we need the number of headlines right now
                # NOTE: white space in headings have been trimmed in handleHeadings. They shouldn't
                # be trimmed here since whitespace in HTML headings is significant.
                $matches = [];
                $numMatches = preg_match_all(
                        '/<H(?P<level>[1-6])(?P<attrib>.*?>)(?P<header>[\s\S]*?)<\/H[1-6] *>/i',
                        $text,
                        $matches
                );

                # if there are fewer than 4 headlines in the article, do not show TOC
                # unless it's been explicitly enabled.
                $enoughToc = $this->mShowToc &&
                        ( ( $numMatches >= 4 ) || $this->mForceTocPosition );

                # Allow user to stipulate that a page should have a "new section"
                # link added via __NEWSECTIONLINK__
                if ( isset( $this->mDoubleUnderscores['newsectionlink'] ) ) {
                        $this->mOutput->setNewSection( true );
                }

                # Allow user to remove the "new section"
                # link via __NONEWSECTIONLINK__
                if ( isset( $this->mDoubleUnderscores['nonewsectionlink'] ) ) {
                        $this->mOutput->setHideNewSection( true );
                }

                # if the string __FORCETOC__ (not case-sensitive) occurs in the HTML,
                # override above conditions and always show TOC above first header
                if ( isset( $this->mDoubleUnderscores['forcetoc'] ) ) {
                        $this->mShowToc = true;
                        $enoughToc = true;
                }

                # headline counter
                $headlineCount = 0;
                $haveTocEntries = false;

                # Ugh .. the TOC should have neat indentation levels which can be
                # passed to the skin functions. These are determined here
                $full = '';
                $head = [];
                $level = 0;
                $tocData = new TOCData();
                $markerRegex = self::MARKER_PREFIX . "-h-(\d+)-" . self::MARKER_SUFFIX;
                $baseTitleText = $this->getTitle()->getPrefixedDBkey();
                $oldType = $this->mOutputType;
                $this->setOutputType( self::OT_WIKI );
                $frame = $this->getPreprocessor()->newFrame();
                $root = $this->preprocessToDom( $origText );
                $node = $root->getFirstChild();
                $cpOffset = 0;
                $refers = [];

                $headlines = $numMatches !== false ? $matches[3] : [];

                $maxTocLevel = $this->svcOptions->get( MainConfigNames::MaxTocLevel );
                foreach ( $headlines as $headline ) {
                        $isTemplate = false;
                        $titleText = false;
                        $sectionIndex = false;
                        $markerMatches = [];
                        if ( preg_match( "/^$markerRegex/", $headline, $markerMatches ) ) {
                                $serial = (int)$markerMatches[1];
                                [ $titleText, $sectionIndex ] = $this->mHeadings[$serial];
                                $isTemplate = ( $titleText != $baseTitleText );
                                $headline = preg_replace( "/^$markerRegex\\s*/", "", $headline );
                        }

                        $sectionMetadata = SectionMetadata::fromLegacy( [
                                "fromtitle" => $titleText ?: null,
                                "index" => $sectionIndex === false
                                        ? '' : ( ( $isTemplate ? 'T-' : '' ) . $sectionIndex )
                        ] );
                        $tocData->addSection( $sectionMetadata );

                        $oldLevel = $level;
                        $level = (int)$matches[1][$headlineCount];
                        $tocData->processHeading( $oldLevel, $level, $sectionMetadata );

                        if ( $tocData->getCurrentTOCLevel() < $maxTocLevel ) {
                                $haveTocEntries = true;
                        }

                        # The safe header is a version of the header text safe to use for links

                        # Remove link placeholders by the link text.
                        #     <!--LINK number-->
                        # turns into
                        #     link text with suffix
                        # Do this before unstrip since link text can contain strip markers
                        $safeHeadline = $this->replaceLinkHoldersText( $headline );

                        # Avoid insertion of weird stuff like <math> by expanding the relevant sections
                        $safeHeadline = $this->mStripState->unstripBoth( $safeHeadline );

                        # Remove any <style> or <script> tags (T198618)
                        $safeHeadline = preg_replace(
                                '#<(style|script)(?: [^>]*[^>/])?>.*?</\1>#is',
                                '',
                                $safeHeadline
                        );

                        # Strip out HTML (first regex removes any tag not allowed)
                        # Allowed tags are:
                        # * <sup> and <sub> (T10393)
                        # * <i> (T28375)
                        # * <b> (r105284)
                        # * <bdi> (T74884)
                        # * <span dir="rtl"> and <span dir="ltr"> (T37167)
                        # * <s> and <strike> (T35715)
                        # * <q> (T251672)
                        # We strip any parameter from accepted tags (second regex), except dir="rtl|ltr" from <span>,
                        # to allow setting directionality in toc items.
                        $tocline = preg_replace(
                                [
                                        '#<(?!/?(span|sup|sub|bdi|i|b|s|strike|q)(?: [^>]*)?>).*?>#',
                                        '#<(/?(?:span(?: dir="(?:rtl|ltr)")?|sup|sub|bdi|i|b|s|strike))(?: .*?)?>#'
                                ],
                                [ '', '<$1>' ],
                                $safeHeadline
                        );

                        # Strip '<span></span>', which is the result from the above if
                        # <span id="foo"></span> is used to produce an additional anchor
                        # for a section.
                        $tocline = str_replace( '<span></span>', '', $tocline );

                        $tocline = trim( $tocline );

                        # For the anchor, strip out HTML-y stuff period
                        $safeHeadline = preg_replace( '/<.*?>/', '', $safeHeadline );
                        $safeHeadline = Sanitizer::normalizeSectionNameWhitespace( $safeHeadline );

                        # Save headline for section edit hint before it's escaped
                        $headlineHint = $safeHeadline;

                        # Decode HTML entities
                        $safeHeadline = Sanitizer::decodeCharReferences( $safeHeadline );

                        $safeHeadline = self::normalizeSectionName( $safeHeadline );

                        $fallbackHeadline = Sanitizer::escapeIdForAttribute( $safeHeadline, Sanitizer::ID_FALLBACK );
                        $linkAnchor = Sanitizer::escapeIdForLink( $safeHeadline );
                        $safeHeadline = Sanitizer::escapeIdForAttribute( $safeHeadline, Sanitizer::ID_PRIMARY );
                        if ( $fallbackHeadline === $safeHeadline ) {
                                # No reason to have both (in fact, we can't)
                                $fallbackHeadline = false;
                        }

                        # HTML IDs must be case-insensitively unique for IE compatibility (T12721).
                        $arrayKey = strtolower( $safeHeadline );
                        if ( $fallbackHeadline === false ) {
                                $fallbackArrayKey = false;
                        } else {
                                $fallbackArrayKey = strtolower( $fallbackHeadline );
                        }

                        # Create the anchor for linking from the TOC to the section
                        $anchor = $safeHeadline;
                        $fallbackAnchor = $fallbackHeadline;
                        if ( isset( $refers[$arrayKey] ) ) {
                                for ( $i = 2; isset( $refers["{$arrayKey}_$i"] ); ++$i );
                                $anchor .= "_$i";
                                $linkAnchor .= "_$i";
                                $refers["{$arrayKey}_$i"] = true;
                        } else {
                                $refers[$arrayKey] = true;
                        }
                        if ( $fallbackHeadline !== false && isset( $refers[$fallbackArrayKey] ) ) {
                                for ( $i = 2; isset( $refers["{$fallbackArrayKey}_$i"] ); ++$i );
                                $fallbackAnchor .= "_$i";
                                $refers["{$fallbackArrayKey}_$i"] = true;
                        } else {
                                $refers[$fallbackArrayKey] = true;
                        }

                        # Add the section to the section tree
                        # Find the DOM node for this header
                        $noOffset = ( $isTemplate || $sectionIndex === false );
                        while ( $node && !$noOffset ) {
                                if ( $node->getName() === 'h' ) {
                                        $bits = $node->splitHeading();
                                        if ( $bits['i'] == $sectionIndex ) {
                                                break;
                                        }
                                }
                                $cpOffset += mb_strlen(
                                        $this->mStripState->unstripBoth(
                                                $frame->expand( $node, PPFrame::RECOVER_ORIG )
                                        )
                                );
                                $node = $node->getNextSibling();
                        }
                        $sectionMetadata->line = $tocline;
                        $sectionMetadata->codepointOffset = ( $noOffset ? null : $cpOffset );
                        $sectionMetadata->anchor = $anchor;
                        $sectionMetadata->linkAnchor = $linkAnchor;

                        # give headline the correct <h#> tag
                        if ( $maybeShowEditLink && $sectionIndex !== false ) {
                                // Output edit section links as markers with styles that can be customized by skins
                                if ( $isTemplate ) {
                                        # Put a T flag in the section identifier, to indicate to extractSections()
                                        # that sections inside <includeonly> should be counted.
                                        $editsectionPage = $titleText;
                                        $editsectionSection = "T-$sectionIndex";
                                } else {
                                        $editsectionPage = $this->getTitle()->getPrefixedText();
                                        $editsectionSection = $sectionIndex;
                                }
                                $editsectionContent = $headlineHint;
                                // We use a bit of pesudo-xml for editsection markers. The
                                // language converter is run later on. Using a UNIQ style marker
                                // leads to the converter screwing up the tokens when it
                                // converts stuff. And trying to insert strip tags fails too. At
                                // this point all real inputted tags have already been escaped,
                                // so we don't have to worry about a user trying to input one of
                                // these markers directly. We use a page and section attribute
                                // to stop the language converter from converting these
                                // important bits of data, but put the headline hint inside a
                                // content block because the language converter is supposed to
                                // be able to convert that piece of data.
                                // Gets replaced with html in ParserOutput::getText
                                $editlink = '<mw:editsection page="' . htmlspecialchars( $editsectionPage, ENT_COMPAT );
                                $editlink .= '" section="' . htmlspecialchars( $editsectionSection, ENT_COMPAT ) . '"';
                                $editlink .= '>' . $editsectionContent . '</mw:editsection>';
                        } else {
                                $editlink = '';
                        }
                        $head[$headlineCount] = Linker::makeHeadline(
                                $level,
                                $matches['attrib'][$headlineCount],
                                $anchor,
                                $headline,
                                $editlink,
                                $fallbackAnchor
                        );

                        $headlineCount++;
                }

                $this->setOutputType( $oldType );

                # Never ever show TOC if no headers (or suppressed)
                $suppressToc = $this->mOptions->getSuppressTOC();
                if ( !$haveTocEntries ) {
                        $enoughToc = false;
                }
                $addTOCPlaceholder = false;

                if ( $isMain && !$suppressToc ) {
                        // We generally output the section information via the API
                        // even if there isn't "enough" of a ToC to merit showing
                        // it -- but the "suppress TOC" parser option is set when
                        // any sections that might be found aren't "really there"
                        // (ie, JavaScript content that might have spurious === or
                        // <h2>: T307691) so we will *not* set section information
                        // in that case.
                        $this->mOutput->setTOCData( $tocData );

                        // T294950: Record a suggestion that the TOC should be shown.
                        // We shouldn't be looking at ::getTOCHTML() for this because
                        // that was replaced (T293513); and $tocData will contain sections
                        // even if there aren't $enoughToc to show (T332243).
                        // Skins are free to ignore this suggestion and implement their
                        // own criteria for showing/suppressing TOC (T318186).
                        if ( $enoughToc ) {
                                $this->mOutput->setOutputFlag( ParserOutputFlags::SHOW_TOC );
                                if ( !$this->mForceTocPosition ) {
                                        $addTOCPlaceholder = true;
                                }
                        }

                        // If __NOTOC__ is used on the page (and not overridden by
                        // __TOC__ or __FORCETOC__) set the NO_TOC flag to tell
                        // the skin that although the section information is
                        // valid, it should perhaps not be presented as a Table Of
                        // Contents.
                        if ( !$this->mShowToc ) {
                                $this->mOutput->setOutputFlag( ParserOutputFlags::NO_TOC );
                        }
                }

                # split up and insert constructed headlines
                $blocks = preg_split( '/<H[1-6].*?>[\s\S]*?<\/H[1-6]>/i', $text );
                $i = 0;

                // build an array of document sections
                $sections = [];
                foreach ( $blocks as $block ) {
                        // $head is zero-based, sections aren't.
                        if ( empty( $head[$i - 1] ) ) {
                                $sections[$i] = $block;
                        } else {
                                $sections[$i] = $head[$i - 1] . $block;
                        }

                        $i++;
                }

                if ( $addTOCPlaceholder ) {
                        // append the TOC at the beginning
                        // Top anchor now in skin
                        // @phan-suppress-next-line PhanTypePossiblyInvalidDimOffset At least one element when enoughToc is true
                        $sections[0] .= self::TOC_PLACEHOLDER . "\n";
                }

                $full .= implode( '', $sections );

                return $full;
        }

        /**
         * Localize the TOC into the given target language; this includes
         * invoking the language converter on the headings.
         * @param ?TOCData $tocData The Table of Contents
         * @param Language $lang The target language
         * @param ?ILanguageConverter $converter The target language converter, or
         *   null if language conversion is to be suppressed.
         * @internal
         */
        private static function localizeTOC(
                ?TOCData $tocData, Language $lang, ?ILanguageConverter $converter
        ) {
                if ( $tocData === null ) {
                        return; // Nothing to do
                }
                foreach ( $tocData->getSections() as $s ) {
                        // Localize heading
                        if ( $converter ) {
                                // T331316: don't use 'convert' or 'convertTo' as these reset
                                // the language converter state.
                                $s->line = $converter->convertTo(
                                        $s->line, $converter->getPreferredVariant(), false
                                );
                        }
                        // Localize numbering
                        $dot = '.';
                        $pieces = explode( $dot, $s->number );
                        $numbering = '';
                        foreach ( $pieces as $i => $p ) {
                                if ( $i > 0 ) {
                                        $numbering .= $dot;
                                }
                                $numbering .= $lang->formatNum( $p );
                        }
                        $s->number = $numbering;
                }
        }

        /**
         * Transform wiki markup when saving a page by doing "\r\n" -> "\n"
         * conversion, substituting signatures, {{subst:}} templates, etc.
         *
         * @param string $text The text to transform
         * @param PageReference $page the current article
         * @param UserIdentity $user the current user
         * @param ParserOptions $options Parsing options
         * @param bool $clearState Whether to clear the parser state first
         * @return string The altered wiki markup
         * @since 1.3
         */
        public function preSaveTransform(
                $text,
                PageReference $page,
                UserIdentity $user,
                ParserOptions $options,
                $clearState = true
        ) {
                if ( $clearState ) {
                        $magicScopeVariable = $this->lock();
                }
                $this->startParse( $page, $options, self::OT_WIKI, $clearState );
                $this->setUser( $user );

                // Strip U+0000 NULL (T159174)
                $text = str_replace( "\000", '', $text );

                // We still normalize line endings (including trimming trailing whitespace) for
                // backwards-compatibility with other code that just calls PST, but this should already
                // be handled in TextContent subclasses
                $text = TextContent::normalizeLineEndings( $text );

                if ( $options->getPreSaveTransform() ) {
                        $text = $this->pstPass2( $text, $user );
                }
                $text = $this->mStripState->unstripBoth( $text );

                // Trim trailing whitespace again, because the previous steps can introduce it.
                $text = rtrim( $text );

                $this->hookRunner->onParserPreSaveTransformComplete( $this, $text );

                $this->setUser( null ); # Reset

                return $text;
        }

        /**
         * Pre-save transform helper function
         *
         * @param string $text
         * @param UserIdentity $user
         *
         * @return string
         */
        private function pstPass2( $text, UserIdentity $user ) {
                # Note: This is the timestamp saved as hardcoded wikitext to the database, we use
                # $this->contLang here in order to give everyone the same signature and use the default one
                # rather than the one selected in each user's preferences.  (see also T14815)
                $ts = $this->mOptions->getTimestamp();
                $timestamp = MWTimestamp::getLocalInstance( $ts );
                $ts = $timestamp->format( 'YmdHis' );
                $tzMsg = $timestamp->getTimezoneMessage()->inContentLanguage()->text();

                $d = $this->contLang->timeanddate( $ts, false, false ) . " ($tzMsg)";

                # Variable replacement
                # Because mOutputType is OT_WIKI, this will only process {{subst:xxx}} type tags
                $text = $this->replaceVariables( $text );

                # This works almost by chance, as the replaceVariables are done before the getUserSig(),
                # which may corrupt this parser instance via its wfMessage()->text() call-

                # Signatures
                if ( strpos( $text, '~~~' ) !== false ) {
                        $sigText = $this->getUserSig( $user );
                        $text = strtr( $text, [
                                '~~~~~' => $d,
                                '~~~~' => "$sigText $d",
                                '~~~' => $sigText
                        ] );
                        # The main two signature forms used above are time-sensitive
                        $this->setOutputFlag( ParserOutputFlags::USER_SIGNATURE, 'User signature detected' );
                }

                # Context links ("pipe tricks"): [[|name]] and [[name (context)|]]
                $tc = '[' . Title::legalChars() . ']';
                $nc = '[ _0-9A-Za-z\x80-\xff-]'; # Namespaces can use non-ascii!

                // [[ns:page (context)|]]
                $p1 = "/\[\[(:?$nc+:|:|)($tc+?)( ?\\($tc+\\))\\|]]/";
                // [[ns:page（context）|]] (double-width brackets, added in r40257)
                $p4 = "/\[\[(:?$nc+:|:|)($tc+?)( ?（$tc+）)\\|]]/";
                // [[ns:page (context), context|]] (using single, double-width or Arabic comma)
                $p3 = "/\[\[(:?$nc+:|:|)($tc+?)( ?\\($tc+\\)|)((?:, |，|، )$tc+|)\\|]]/";
                // [[|page]] (reverse pipe trick: add context from page title)
                $p2 = "/\[\[\\|($tc+)]]/";

                # try $p1 first, to turn "[[A, B (C)|]]" into "[[A, B (C)|A, B]]"
                $text = preg_replace( $p1, '[[\\1\\2\\3|\\2]]', $text );
                $text = preg_replace( $p4, '[[\\1\\2\\3|\\2]]', $text );
                $text = preg_replace( $p3, '[[\\1\\2\\3\\4|\\2]]', $text );

                $t = $this->getTitle()->getText();
                $m = [];
                if ( preg_match( "/^($nc+:|)$tc+?( \\($tc+\\))$/", $t, $m ) ) {
                        $text = preg_replace( $p2, "[[$m[1]\\1$m[2]|\\1]]", $text );
                } elseif ( preg_match( "/^($nc+:|)$tc+?(, $tc+|)$/", $t, $m ) && "$m[1]$m[2]" != '' ) {
                        $text = preg_replace( $p2, "[[$m[1]\\1$m[2]|\\1]]", $text );
                } else {
                        # if there's no context, don't bother duplicating the title
                        $text = preg_replace( $p2, '[[\\1]]', $text );
                }

                return $text;
        }

        /**
         * Fetch the user's signature text, if any, and normalize to
         * validated, ready-to-insert wikitext.
         * If you have pre-fetched the nickname or the fancySig option, you can
         * specify them here to save a database query.
         * Do not reuse this parser instance after calling getUserSig(),
         * as it may have changed.
         *
         * @param UserIdentity $user
         * @param string|false $nickname Nickname to use or false to use user's default nickname
         * @param bool|null $fancySig whether the nicknname is the complete signature
         *    or null to use default value
         * @return string
         * @since 1.6
         */
        public function getUserSig( UserIdentity $user, $nickname = false, $fancySig = null ) {
                $username = $user->getName();

                # If not given, retrieve from the user object.
                if ( $nickname === false ) {
                        $nickname = $this->userOptionsLookup->getOption( $user, 'nickname' );
                }

                if ( $fancySig === null ) {
                        $fancySig = $this->userOptionsLookup->getBoolOption( $user, 'fancysig' );
                }

                if ( $nickname === null || $nickname === '' ) {
                        // Empty value results in the default signature (even when fancysig is enabled)
                        $nickname = $username;
                } elseif ( mb_strlen( $nickname ) > $this->svcOptions->get( MainConfigNames::MaxSigChars ) ) {
                        $nickname = $username;
                        $this->logger->debug( __METHOD__ . ": $username has overlong signature." );
                } elseif ( $fancySig !== false ) {
                        # Sig. might contain markup; validate this
                        $isValid = $this->validateSig( $nickname ) !== false;

                        # New validator
                        $sigValidation = $this->svcOptions->get( MainConfigNames::SignatureValidation );
                        if ( $isValid && $sigValidation === 'disallow' ) {
                                $parserOpts = new ParserOptions(
                                        $this->mOptions->getUserIdentity(),
                                        $this->contLang
                                );
                                $validator = $this->signatureValidatorFactory
                                        ->newSignatureValidator( $user, null, $parserOpts );
                                $isValid = !$validator->validateSignature( $nickname );
                        }

                        if ( $isValid ) {
                                # Validated; clean up (if needed) and return it
                                return $this->cleanSig( $nickname, true );
                        } else {
                                # Failed to validate; fall back to the default
                                $nickname = $username;
                                $this->logger->debug( __METHOD__ . ": $username has invalid signature." );
                        }
                }

                # Make sure nickname doesnt get a sig in a sig
                $nickname = self::cleanSigInSig( $nickname );

                # If we're still here, make it a link to the user page
                $userText = wfEscapeWikiText( $username );
                $nickText = wfEscapeWikiText( $nickname );
                if ( $this->userNameUtils->isTemp( $username ) ) {
                        $msgName = 'signature-temp';
                } elseif ( $user->isRegistered() ) {
                        $msgName = 'signature';
                } else {
                        $msgName = 'signature-anon';
                }

                return wfMessage( $msgName, $userText, $nickText )->inContentLanguage()
                        ->page( $this->getPage() )->text();
        }

        /**
         * Check that the user's signature contains no bad XML
         *
         * @param string $text
         * @return string|false An expanded string, or false if invalid.
         * @since 1.6
         */
        public function validateSig( $text ) {
                return Xml::isWellFormedXmlFragment( $text ) ? $text : false;
        }

        /**
         * Clean up signature text
         *
         * 1) Strip 3, 4 or 5 tildes out of signatures @see cleanSigInSig
         * 2) Substitute all transclusions
         *
         * @param string $text
         * @param bool $parsing Whether we're cleaning (preferences save) or parsing
         * @return string Signature text
         * @since 1.6
         */
        public function cleanSig( $text, $parsing = false ) {
                if ( !$parsing ) {
                        $magicScopeVariable = $this->lock();
                        $this->startParse(
                                $this->mTitle,
                                ParserOptions::newFromUser( RequestContext::getMain()->getUser() ),
                                self::OT_PREPROCESS,
                                true
                        );
                }

                # Option to disable this feature
                if ( !$this->mOptions->getCleanSignatures() ) {
                        return $text;
                }

                # @todo FIXME: Regex doesn't respect extension tags or nowiki
                #  => Move this logic to braceSubstitution()
                $substWord = $this->magicWordFactory->get( 'subst' );
                $substRegex = '/\{\{(?!(?:' . $substWord->getBaseRegex() . '))/x' . $substWord->getRegexCase();
                $substText = '{{' . $substWord->getSynonym( 0 );

                $text = preg_replace( $substRegex, $substText, $text );
                $text = self::cleanSigInSig( $text );
                $dom = $this->preprocessToDom( $text );
                $frame = $this->getPreprocessor()->newFrame();
                $text = $frame->expand( $dom );

                if ( !$parsing ) {
                        $text = $this->mStripState->unstripBoth( $text );
                }

                return $text;
        }

        /**
         * Strip 3, 4 or 5 tildes out of signatures.
         *
         * @param string $text
         * @return string Signature text with /~{3,5}/ removed
         * @since 1.7
         */
        public static function cleanSigInSig( $text ) {
                $text = preg_replace( '/~{3,5}/', '', $text );
                return $text;
        }

        /**
         * Replace table of contents marker in parsed HTML.
         *
         * Used to remove or replace the marker.  This method should be
         * used instead of direct access to Parser::TOC_PLACEHOLDER, since
         * in the future the placeholder might have additional attributes
         * attached which should be ignored when the replacement is made.
         *
         * @since 1.38
         * @stable
         *
         * @param string $text Parsed HTML
         * @param string $toc HTML table of contents string, or else an empty
         *   string to remove the marker.
         * @return string Result HTML
         */
        public static function replaceTableOfContentsMarker( $text, $toc ) {
                return preg_replace( self::TOC_PLACEHOLDER_REGEX,
                        StringUtils::escapeRegexReplacement( $toc ), $text );
        }

        /**
         * Set up some variables which are usually set up in parse()
         * so that an external function can call some class members with confidence
         *
         * @param ?PageReference $page
         * @param ParserOptions $options
         * @param int $outputType One of the Parser::OT_… constants
         * @param bool $clearState
         * @param int|null $revId
         * @since 1.3
         */
        public function startExternalParse( ?PageReference $page, ParserOptions $options,
                $outputType, $clearState = true, $revId = null
        ) {
                $this->startParse( $page, $options, $outputType, $clearState );
                if ( $revId !== null ) {
                        $this->mRevisionId = $revId;
                }
        }

        /**
         * @param ?PageReference $page
         * @param ParserOptions $options
         * @param int $outputType
         * @param bool $clearState
         */
        private function startParse( ?PageReference $page, ParserOptions $options,
                $outputType, $clearState = true
        ) {
                $this->setPage( $page );
                $this->mOptions = $options;
                $this->setOutputType( $outputType );
                if ( $clearState ) {
                        $this->clearState();
                }
        }

        /**
         * Wrapper for preprocess()
         *
         * @param string $text The text to preprocess
         * @param ParserOptions $options
         * @param ?PageReference $page The context page
         * @return string
         * @since 1.3
         */
        public function transformMsg( $text, ParserOptions $options, ?PageReference $page = null ) {
                static $executing = false;

                # Guard against infinite recursion
                if ( $executing ) {
                        return $text;
                }
                $executing = true;

                $text = $this->preprocess( $text, $page ?? $this->mTitle, $options );

                $executing = false;
                return $text;
        }

        /**
         * Create an HTML-style tag, e.g. "<yourtag>special text</yourtag>"
         * The callback should have the following form:
         *    function myParserHook( $text, array $params, Parser $parser, PPFrame $frame ) { ... }
         *
         * Transform and return $text. Use $parser for any required context, e.g. use
         * $parser->getTitle() and $parser->getOptions() not $wgTitle or $wgOut->mParserOptions
         *
         * Hooks may return extended information by returning an array, of which the
         * first numbered element (index 0) must be the return string. The following other
         * keys are used:
         *  - 'markerType': used by some core tag hooks to override which strip
         *    array their results are placed in, 'general' or 'nowiki'.
         *
         * @param string $tag The tag to use, e.g. 'hook' for "<hook>"
         * @param callable $callback The callback to use for the tag
         * @return callable|null The old value of the mTagHooks array associated with the hook
         * @since 1.3
         */
        public function setHook( $tag, callable $callback ) {
                $tag = strtolower( $tag );
                if ( preg_match( '/[<>\r\n]/', $tag, $m ) ) {
                        throw new InvalidArgumentException( "Invalid character {$m[0]} in setHook('$tag', ...) call" );
                }
                $oldVal = $this->mTagHooks[$tag] ?? null;
                $this->mTagHooks[$tag] = $callback;
                if ( !in_array( $tag, $this->mStripList ) ) {
                        $this->mStripList[] = $tag;
                }

                return $oldVal;
        }

        /**
         * Remove all tag hooks
         * @since 1.12
         */
        public function clearTagHooks() {
                $this->mTagHooks = [];
                $this->mStripList = [];
        }

        /**
         * Create a function, e.g. {{sum:1|2|3}}
         * The callback function should have the form:
         *    function myParserFunction( &$parser, $arg1, $arg2, $arg3 ) { ... }
         *
         * Or with Parser::SFH_OBJECT_ARGS:
         *    function myParserFunction( $parser, $frame, $args ) { ... }
         *
         * The callback may either return the text result of the function, or an array with the text
         * in element 0, and a number of flags in the other elements. The names of the flags are
         * specified in the keys. Valid flags are:
         *   found                     The text returned is valid, stop processing the template. This
         *                             is on by default.
         *   nowiki                    Wiki markup in the return value should be escaped
         *   isHTML                    The returned text is HTML, armour it against wikitext transformation
         *
         * @param string $id The magic word ID
         * @param callable $callback The callback function (and object) to use
         * @param int $flags A combination of the following flags:
         *     Parser::SFH_NO_HASH      No leading hash, i.e. {{plural:...}} instead of {{#if:...}}
         *
         *     Parser::SFH_OBJECT_ARGS  Pass the template arguments as PPNode objects instead of text.
         *     This allows for conditional expansion of the parse tree, allowing you to eliminate dead
         *     branches and thus speed up parsing. It is also possible to analyse the parse tree of
         *     the arguments, and to control the way they are expanded.
         *
         *     The $frame parameter is a PPFrame. This can be used to produce expanded text from the
         *     arguments, for instance:
         *         $text = isset( $args[0] ) ? $frame->expand( $args[0] ) : '';
         *
         *     For technical reasons, $args[0] is pre-expanded and will be a string. This may change in
         *     future versions. Please call $frame->expand() on it anyway so that your code keeps
         *     working if/when this is changed.
         *
         *     If you want whitespace to be trimmed from $args, you need to do it yourself, post-
         *     expansion.
         *
         *     Please read the documentation in includes/parser/Preprocessor.php for more information
         *     about the methods available in PPFrame and PPNode.
         *
         * @return string|callable|null The old callback function for this name, if any
         * @since 1.6
         */
        public function setFunctionHook( $id, callable $callback, $flags = 0 ) {
                $oldVal = $this->mFunctionHooks[$id][0] ?? null;
                $this->mFunctionHooks[$id] = [ $callback, $flags ];

                # Add to function cache
                $mw = $this->magicWordFactory->get( $id );
                if ( !$mw ) {
                        throw new InvalidArgumentException( __METHOD__ . '() expecting a magic word identifier.' );
                }

                $synonyms = $mw->getSynonyms();
                $sensitive = intval( $mw->isCaseSensitive() );

                foreach ( $synonyms as $syn ) {
                        # Case
                        if ( !$sensitive ) {
                                $syn = $this->contLang->lc( $syn );
                        }
                        # Add leading hash
                        if ( !( $flags & self::SFH_NO_HASH ) ) {
                                $syn = '#' . $syn;
                        }
                        # Remove trailing colon
                        if ( substr( $syn, -1, 1 ) === ':' ) {
                                $syn = substr( $syn, 0, -1 );
                        }
                        $this->mFunctionSynonyms[$sensitive][$syn] = $id;
                }
                return $oldVal;
        }

        /**
         * Get all registered function hook identifiers
         *
         * @return array
         * @since 1.8
         */
        public function getFunctionHooks() {
                return array_keys( $this->mFunctionHooks );
        }

        /**
         * Replace "<!--LINK-->" link placeholders with actual links, in the buffer
         * Placeholders created in Linker::link()
         *
         * @param string &$text
         * @deprecated since 1.34; should not be used outside parser class.
         */
        public function replaceLinkHolders( &$text ) {
                $this->replaceLinkHoldersPrivate( $text );
        }

        /**
         * Replace "<!--LINK-->" link placeholders with actual links, in the buffer
         * Placeholders created in Linker::link()
         *
         * @param string &$text
         */
        private function replaceLinkHoldersPrivate( &$text ) {
                $this->mLinkHolders->replace( $text );
        }

        /**
         * Replace "<!--LINK-->" link placeholders with plain text of links
         * (not HTML-formatted).
         *
         * @param string $text
         * @return string
         */
        private function replaceLinkHoldersText( $text ) {
                return $this->mLinkHolders->replaceText( $text );
        }

        /**
         * Renders an image gallery from a text with one line per image.
         * text labels may be given by using |-style alternative text. E.g.
         *   Image:one.jpg|The number "1"
         *   Image:tree.jpg|A tree
         * given as text will return the HTML of a gallery with two images,
         * labeled 'The number "1"' and
         * 'A tree'.
         *
         * @param string $text
         * @param array $params
         * @return string HTML
         * @internal
         */
        public function renderImageGallery( $text, array $params ) {
                $mode = false;
                if ( isset( $params['mode'] ) ) {
                        $mode = $params['mode'];
                }

                try {
                        $ig = ImageGalleryBase::factory( $mode );
                } catch ( ImageGalleryClassNotFoundException $e ) {
                        // If invalid type set, fallback to default.
                        $ig = ImageGalleryBase::factory( false );
                }

                $ig->setContextTitle( $this->getTitle() );
                $ig->setShowBytes( false );
                $ig->setShowDimensions( false );
                $ig->setShowFilename( false );
                $ig->setParser( $this );
                $ig->setHideBadImages();
                $ig->setAttributes( Sanitizer::validateTagAttributes( $params, 'ul' ) );

                if ( isset( $params['showfilename'] ) ) {
                        $ig->setShowFilename( true );
                } else {
                        $ig->setShowFilename( false );
                }
                if ( isset( $params['caption'] ) ) {
                        // NOTE: We aren't passing a frame here or below.  Frame info
                        // is currently opaque to Parsoid, which acts on OT_PREPROCESS.
                        // See T107332#4030581
                        $caption = $this->recursiveTagParse( $params['caption'] );
                        $ig->setCaptionHtml( $caption );
                }
                if ( isset( $params['perrow'] ) ) {
                        $ig->setPerRow( $params['perrow'] );
                }
                if ( isset( $params['widths'] ) ) {
                        $ig->setWidths( $params['widths'] );
                }
                if ( isset( $params['heights'] ) ) {
                        $ig->setHeights( $params['heights'] );
                }
                $ig->setAdditionalOptions( $params );

                $enableLegacyMediaDOM = $this->svcOptions->get( MainConfigNames::ParserEnableLegacyMediaDOM );

                $lines = StringUtils::explode( "\n", $text );
                foreach ( $lines as $line ) {
                        # match lines like these:
                        # Image:someimage.jpg|This is some image
                        $matches = [];
                        preg_match( "/^([^|]+)(\\|(.*))?$/", $line, $matches );
                        # Skip empty lines
                        if ( count( $matches ) == 0 ) {
                                continue;
                        }

                        if ( strpos( $matches[0], '%' ) !== false ) {
                                $matches[1] = rawurldecode( $matches[1] );
                        }
                        $title = Title::newFromText( $matches[1], NS_FILE );
                        if ( $title === null ) {
                                # Bogus title. Ignore these so we don't bomb out later.
                                continue;
                        }

                        # We need to get what handler the file uses, to figure out parameters.
                        # Note, a hook can override the file name, and chose an entirely different
                        # file (which potentially could be of a different type and have different handler).
                        $options = [];
                        $descQuery = false;
                        $this->hookRunner->onBeforeParserFetchFileAndTitle(
                                // @phan-suppress-next-line PhanTypeMismatchArgument Type mismatch on pass-by-ref args
                                $this, $title, $options, $descQuery
                        );
                        # Don't register it now, as TraditionalImageGallery does that later.
                        $file = $this->fetchFileNoRegister( $title, $options );
                        $handler = $file ? $file->getHandler() : false;

                        $paramMap = [
                                'img_alt' => 'gallery-internal-alt',
                                'img_link' => 'gallery-internal-link',
                        ];
                        if ( $handler ) {
                                $paramMap += $handler->getParamMap();
                                // We don't want people to specify per-image widths.
                                // Additionally the width parameter would need special casing anyhow.
                                unset( $paramMap['img_width'] );
                        }

                        $mwArray = $this->magicWordFactory->newArray( array_keys( $paramMap ) );

                        $label = '';
                        $alt = null;
                        $handlerOptions = [];
                        $imageOptions = [];
                        $hasAlt = false;

                        if ( isset( $matches[3] ) ) {
                                // look for an |alt= definition while trying not to break existing
                                // captions with multiple pipes (|) in it, until a more sensible grammar
                                // is defined for images in galleries

                                // FIXME: Doing recursiveTagParse at this stage, and the trim before
                                // splitting on '|' is a bit odd, and different from makeImage.
                                $matches[3] = $this->recursiveTagParse( trim( $matches[3] ) );
                                // Protect LanguageConverter markup
                                $parameterMatches = StringUtils::delimiterExplode(
                                        '-{', '}-',
                                        '|',
                                        $matches[3],
                                        true /* nested */
                                );

                                foreach ( $parameterMatches as $parameterMatch ) {
                                        [ $magicName, $match ] = $mwArray->matchVariableStartToEnd( $parameterMatch );
                                        if ( !$magicName ) {
                                                // Last pipe wins.
                                                $label = $parameterMatch;
                                                continue;
                                        }

                                        $paramName = $paramMap[$magicName];
                                        switch ( $paramName ) {
                                                case 'gallery-internal-alt':
                                                        $hasAlt = true;
                                                        $alt = $this->stripAltText( $match, false );
                                                        break;
                                                case 'gallery-internal-link':
                                                        $linkValue = $this->stripAltText( $match, false );
                                                        if ( preg_match( '/^-{R\|(.*)}-$/', $linkValue ) ) {
                                                                // Result of LanguageConverter::markNoConversion
                                                                // invoked on an external link.
                                                                $linkValue = substr( $linkValue, 4, -2 );
                                                        }
                                                        [ $type, $target ] = $this->parseLinkParameter( $linkValue );
                                                        if ( $type ) {
                                                                if ( $type === 'no-link' ) {
                                                                        $target = true;
                                                                }
                                                                $imageOptions[$type] = $target;
                                                        }
                                                        break;
                                                default:
                                                        // Must be a handler specific parameter.
                                                        if ( $handler->validateParam( $paramName, $match ) ) {
                                                                $handlerOptions[$paramName] = $match;
                                                        } else {
                                                                // Guess not, consider it as caption.
                                                                $this->logger->debug(
                                                                        "$parameterMatch failed parameter validation" );
                                                                $label = $parameterMatch;
                                                        }
                                        }
                                }
                        }

                        // Match makeImage when !$hasVisibleCaption
                        if ( !$hasAlt ) {
                                if ( $label !== '' ) {
                                        $alt = $this->stripAltText( $label, false );
                                } else {
                                        if ( $enableLegacyMediaDOM ) {
                                                $alt = $title->getText();
                                        }
                                }
                        }
                        $imageOptions['title'] = $this->stripAltText( $label, false );

                        // Match makeImage which sets this unconditionally
                        $handlerOptions['targetlang'] = $this->getTargetLanguage()->getCode();

                        $ig->add(
                                $title, $label, $alt, '', $handlerOptions,
                                ImageGalleryBase::LOADING_DEFAULT, $imageOptions
                        );
                }
                $html = $ig->toHTML();
                $this->hookRunner->onAfterParserFetchFileAndTitle( $this, $ig, $html );
                return $html;
        }

        /**
         * @param MediaHandler|false $handler
         * @return array
         */
        private function getImageParams( $handler ) {
                if ( $handler ) {
                        $handlerClass = get_class( $handler );
                } else {
                        $handlerClass = '';
                }
                if ( !isset( $this->mImageParams[$handlerClass] ) ) {
                        # Initialise static lists
                        static $internalParamNames = [
                                'horizAlign' => [ 'left', 'right', 'center', 'none' ],
                                'vertAlign' => [ 'baseline', 'sub', 'super', 'top', 'text-top', 'middle',
                                        'bottom', 'text-bottom' ],
                                'frame' => [ 'thumbnail', 'manualthumb', 'framed', 'frameless',
                                        'upright', 'border', 'link', 'alt', 'class' ],
                        ];
                        static $internalParamMap;
                        if ( !$internalParamMap ) {
                                $internalParamMap = [];
                                foreach ( $internalParamNames as $type => $names ) {
                                        foreach ( $names as $name ) {
                                                // For grep: img_left, img_right, img_center, img_none,
                                                // img_baseline, img_sub, img_super, img_top, img_text_top, img_middle,
                                                // img_bottom, img_text_bottom,
                                                // img_thumbnail, img_manualthumb, img_framed, img_frameless, img_upright,
                                                // img_border, img_link, img_alt, img_class
                                                $magicName = str_replace( '-', '_', "img_$name" );
                                                $internalParamMap[$magicName] = [ $type, $name ];
                                        }
                                }
                        }

                        # Add handler params
                        $paramMap = $internalParamMap;
                        if ( $handler ) {
                                $handlerParamMap = $handler->getParamMap();
                                foreach ( $handlerParamMap as $magic => $paramName ) {
                                        $paramMap[$magic] = [ 'handler', $paramName ];
                                }
                        } else {
                                // Parse the size for non-existent files.  See T273013
                                $paramMap[ 'img_width' ] = [ 'handler', 'width' ];
                        }
                        $this->mImageParams[$handlerClass] = $paramMap;
                        $this->mImageParamsMagicArray[$handlerClass] =
                                $this->magicWordFactory->newArray( array_keys( $paramMap ) );
                }
                return [ $this->mImageParams[$handlerClass], $this->mImageParamsMagicArray[$handlerClass] ];
        }

        /**
         * Parse image options text and use it to make an image
         *
         * @param LinkTarget $link
         * @param string $options
         * @param LinkHolderArray|false $holders
         * @return string HTML
         * @since 1.5
         */
        public function makeImage( LinkTarget $link, $options, $holders = false ) {
                # Check if the options text is of the form "options|alt text"
                # Options are:
                #  * thumbnail  make a thumbnail with enlarge-icon and caption, alignment depends on lang
                #  * left       no resizing, just left align. label is used for alt= only
                #  * right      same, but right aligned
                #  * none       same, but not aligned
                #  * ___px      scale to ___ pixels width, no aligning. e.g. use in taxobox
                #  * center     center the image
                #  * framed     Keep original image size, no magnify-button.
                #  * frameless  like 'thumb' but without a frame. Keeps user preferences for width
                #  * upright    reduce width for upright images, rounded to full __0 px
                #  * border     draw a 1px border around the image
                #  * alt        Text for HTML alt attribute (defaults to empty)
                #  * class      Set a class for img node
                #  * link       Set the target of the image link. Can be external, interwiki, or local
                # vertical-align values (no % or length right now):
                #  * baseline
                #  * sub
                #  * super
                #  * top
                #  * text-top
                #  * middle
                #  * bottom
                #  * text-bottom

                # Protect LanguageConverter markup when splitting into parts
                $parts = StringUtils::delimiterExplode(
                        '-{', '}-', '|', $options, true /* allow nesting */
                );

                # Give extensions a chance to select the file revision for us
                $options = [];
                $descQuery = false;
                $title = Title::castFromLinkTarget( $link ); // hook signature compat
                $this->hookRunner->onBeforeParserFetchFileAndTitle(
                        // @phan-suppress-next-line PhanTypeMismatchArgument Type mismatch on pass-by-ref args
                        $this, $title, $options, $descQuery
                );
                # Fetch and register the file (file title may be different via hooks)
                [ $file, $link ] = $this->fetchFileAndTitle( $link, $options );

                # Get parameter map
                $handler = $file ? $file->getHandler() : false;

                [ $paramMap, $mwArray ] = $this->getImageParams( $handler );

                if ( !$file ) {
                        $this->addTrackingCategory( 'broken-file-category' );
                }

                # Process the input parameters
                $caption = '';
                $params = [ 'frame' => [], 'handler' => [],
                        'horizAlign' => [], 'vertAlign' => [] ];
                $seenformat = false;
                foreach ( $parts as $part ) {
                        $part = trim( $part );
                        [ $magicName, $value ] = $mwArray->matchVariableStartToEnd( $part );
                        $validated = false;
                        if ( isset( $paramMap[$magicName] ) ) {
                                [ $type, $paramName ] = $paramMap[$magicName];

                                # Special case; width and height come in one variable together
                                if ( $type === 'handler' && $paramName === 'width' ) {
                                        $parsedWidthParam = self::parseWidthParam( $value );
                                        // Parsoid applies data-(width|height) attributes to broken
                                        // media spans, for client use.  See T273013
                                        $validateFunc = static function ( $name, $value ) use ( $handler ) {
                                                return $handler
                                                        ? $handler->validateParam( $name, $value )
                                                        : $value > 0;
                                        };
                                        if ( isset( $parsedWidthParam['width'] ) ) {
                                                $width = $parsedWidthParam['width'];
                                                if ( $validateFunc( 'width', $width ) ) {
                                                        $params[$type]['width'] = $width;
                                                        $validated = true;
                                                }
                                        }
                                        if ( isset( $parsedWidthParam['height'] ) ) {
                                                $height = $parsedWidthParam['height'];
                                                if ( $validateFunc( 'height', $height ) ) {
                                                        $params[$type]['height'] = $height;
                                                        $validated = true;
                                                }
                                        }
                                        # else no validation -- T15436
                                } else {
                                        if ( $type === 'handler' ) {
                                                # Validate handler parameter
                                                $validated = $handler->validateParam( $paramName, $value );
                                        } else {
                                                # Validate internal parameters
                                                switch ( $paramName ) {
                                                        case 'alt':
                                                        case 'class':
                                                                $validated = true;
                                                                $value = $this->stripAltText( $value, $holders );
                                                                break;
                                                        case 'link':
                                                                [ $paramName, $value ] =
                                                                        $this->parseLinkParameter(
                                                                                $this->stripAltText( $value, $holders )
                                                                        );
                                                                if ( $paramName ) {
                                                                        $validated = true;
                                                                        if ( $paramName === 'no-link' ) {
                                                                                $value = true;
                                                                        }
                                                                }
                                                                break;
                                                        case 'manualthumb':
                                                                # @todo FIXME: Possibly check validity here for
                                                                # manualthumb? downstream behavior seems odd with
                                                                # missing manual thumbs.
                                                                $value = $this->stripAltText( $value, $holders );
                                                                // fall through
                                                        case 'frameless':
                                                        case 'framed':
                                                        case 'thumbnail':
                                                                // use first appearing option, discard others.
                                                                $validated = !$seenformat;
                                                                $seenformat = true;
                                                                break;
                                                        default:
                                                                # Most other things appear to be empty or numeric...
                                                                $validated = ( $value === false || is_numeric( trim( $value ) ) );
                                                }
                                        }

                                        if ( $validated ) {
                                                $params[$type][$paramName] = $value;
                                        }
                                }
                        }
                        if ( !$validated ) {
                                $caption = $part;
                        }
                }

                # Process alignment parameters
                if ( $params['horizAlign'] !== [] ) {
                        $params['frame']['align'] = array_key_first( $params['horizAlign'] );
                }
                if ( $params['vertAlign'] !== [] ) {
                        $params['frame']['valign'] = array_key_first( $params['vertAlign'] );
                }

                $params['frame']['caption'] = $caption;

                $enableLegacyMediaDOM = $this->svcOptions->get( MainConfigNames::ParserEnableLegacyMediaDOM );

                # Will the image be presented in a frame, with the caption below?
                // @phan-suppress-next-line PhanImpossibleCondition
                $hasVisibleCaption = isset( $params['frame']['framed'] )
                        // @phan-suppress-next-line PhanImpossibleCondition
                        || isset( $params['frame']['thumbnail'] )
                        // @phan-suppress-next-line PhanImpossibleCondition
                        || isset( $params['frame']['manualthumb'] );

                # In the old days, [[Image:Foo|text...]] would set alt text.  Later it
                # came to also set the caption, ordinary text after the image -- which
                # makes no sense, because that just repeats the text multiple times in
                # screen readers.  It *also* came to set the title attribute.
                # Now that we have an alt attribute, we should not set the alt text to
                # equal the caption: that's worse than useless, it just repeats the
                # text.  This is the framed/thumbnail case.  If there's no caption, we
                # use the unnamed parameter for alt text as well, just for the time be-
                # ing, if the unnamed param is set and the alt param is not.
                # For the future, we need to figure out if we want to tweak this more,
                # e.g., introducing a title= parameter for the title; ignoring the un-
                # named parameter entirely for images without a caption; adding an ex-
                # plicit caption= parameter and preserving the old magic unnamed para-
                # meter for BC; ...
                if ( $hasVisibleCaption ) {
                        if (
                                // @phan-suppress-next-line PhanImpossibleCondition
                                $caption === '' && !isset( $params['frame']['alt'] ) &&
                                $enableLegacyMediaDOM
                        ) {
                                # No caption or alt text, add the filename as the alt text so
                                # that screen readers at least get some description of the image
                                $params['frame']['alt'] = $link->getText();
                        }
                        # Do not set $params['frame']['title'] because tooltips are unnecessary
                        # for framed images, the caption is visible
                } else {
                        // @phan-suppress-next-line PhanImpossibleCondition
                        if ( !isset( $params['frame']['alt'] ) ) {
                                # No alt text, use the "caption" for the alt text
                                if ( $caption !== '' ) {
                                        $params['frame']['alt'] = $this->stripAltText( $caption, $holders );
                                } elseif ( $enableLegacyMediaDOM ) {
                                        # No caption, fall back to using the filename for the
                                        # alt text
                                        $params['frame']['alt'] = $link->getText();
                                }
                        }
                        # Use the "caption" for the tooltip text
                        $params['frame']['title'] = $this->stripAltText( $caption, $holders );
                }
                $params['handler']['targetlang'] = $this->getTargetLanguage()->getCode();

                // hook signature compat again, $link may have changed
                $title = Title::castFromLinkTarget( $link );
                $this->hookRunner->onParserMakeImageParams( $title, $file, $params, $this );

                # Linker does the rest
                $time = $options['time'] ?? false;
                // @phan-suppress-next-line PhanTypePossiblyInvalidDimOffset
                $ret = Linker::makeImageLink( $this, $link, $file, $params['frame'], $params['handler'],
                        $time, $descQuery, $this->mOptions->getThumbSize() );

                # Give the handler a chance to modify the parser object
                if ( $handler ) {
                        $handler->parserTransformHook( $this, $file );
                }
                if ( $file ) {
                        $this->modifyImageHtml( $file, $params, $ret );
                }

                return $ret;
        }

        /**
         * Parse the value of 'link' parameter in image syntax (`[[File:Foo.jpg|link=<value>]]`).
         *
         * Adds an entry to appropriate link tables.
         *
         * @since 1.32
         * @param string $value
         * @return array of `[ type, target ]`, where:
         *   - `type` is one of:
         *     - `null`: Given value is not a valid link target, use default
         *     - `'no-link'`: Given value is empty, do not generate a link
         *     - `'link-url'`: Given value is a valid external link
         *     - `'link-title'`: Given value is a valid internal link
         *   - `target` is:
         *     - When `type` is `null` or `'no-link'`: `false`
         *     - When `type` is `'link-url'`: URL string corresponding to given value
         *     - When `type` is `'link-title'`: Title object corresponding to given value
         */
        private function parseLinkParameter( $value ) {
                $chars = self::EXT_LINK_URL_CLASS;
                $addr = self::EXT_LINK_ADDR;
                $prots = $this->urlUtils->validProtocols();
                $type = null;
                $target = false;
                if ( $value === '' ) {
                        $type = 'no-link';
                } elseif ( preg_match( "/^((?i)$prots)/", $value ) ) {
                        if ( preg_match( "/^((?i)$prots)$addr$chars*$/u", $value ) ) {
                                $this->mOutput->addExternalLink( $value );
                                $type = 'link-url';
                                $target = $value;
                        }
                } else {
                        // Percent-decode link arguments for consistency with wikilink
                        // handling (T216003#7836261).
                        //
                        // There's slight concern here though.  The |link= option supports
                        // two formats, link=Test%22test vs link=[[Test%22test]], both of
                        // which are about to be decoded.
                        //
                        // In the former case, the decoding here is straightforward and
                        // desirable.
                        //
                        // In the latter case, there's a potential for double decoding,
                        // because the wikilink syntax has a higher precedence and has
                        // already been parsed as a link before we get here.  $value
                        // has had stripAltText() called on it, which in turn calls
                        // replaceLinkHoldersText() on the link.  So, the text we're
                        // getting at this point has already been percent decoded.
                        //
                        // The problematic case is if %25 is in the title, since that
                        // decodes to %, which could combine with trailing characters.
                        // However, % is not a valid link title character, so it would
                        // not parse as a link and the string we received here would
                        // still contain the encoded %25.
                        //
                        // Hence, double decoded is not an issue.  See the test,
                        // "Should not double decode the link option"
                        if ( strpos( $value, '%' ) !== false ) {
                                $value = rawurldecode( $value );
                        }
                        $linkTitle = Title::newFromText( $value );
                        if ( $linkTitle ) {
                                $this->mOutput->addLink( $linkTitle );
                                $type = 'link-title';
                                $target = $linkTitle;
                        }
                }
                return [ $type, $target ];
        }

        /**
         * Give hooks a chance to modify image thumbnail HTML
         *
         * @param File $file
         * @param array $params
         * @param string &$html
         */
        public function modifyImageHtml( File $file, array $params, string &$html ) {
                $this->hookRunner->onParserModifyImageHTML( $this, $file, $params, $html );
        }

        /**
         * @param string $caption
         * @param LinkHolderArray|false $holders
         * @return string
         */
        private function stripAltText( $caption, $holders ) {
                # Strip bad stuff out of the title (tooltip).  We can't just use
                # replaceLinkHoldersText() here, because if this function is called
                # from handleInternalLinks2(), mLinkHolders won't be up-to-date.
                if ( $holders ) {
                        $tooltip = $holders->replaceText( $caption );
                } else {
                        $tooltip = $this->replaceLinkHoldersText( $caption );
                }

                # make sure there are no placeholders in thumbnail attributes
                # that are later expanded to html- so expand them now and
                # remove the tags
                $tooltip = $this->mStripState->unstripBoth( $tooltip );
                # Compatibility hack!  In HTML certain entity references not terminated
                # by a semicolon are decoded (but not if we're in an attribute; that's
                # how link URLs get away without properly escaping & in queries).
                # But wikitext has always required semicolon-termination of entities,
                # so encode & where needed to avoid decode of semicolon-less entities.
                # See T209236 and
                # https://www.w3.org/TR/html5/syntax.html#named-character-references
                # T210437 discusses moving this workaround to Sanitizer::stripAllTags.
                $tooltip = preg_replace( "/
                        &                       # 1. entity prefix
                        (?=                     # 2. followed by:
                        (?:                     #  a. one of the legacy semicolon-less named entities
                                A(?:Elig|MP|acute|circ|grave|ring|tilde|uml)|
                                C(?:OPY|cedil)|E(?:TH|acute|circ|grave|uml)|
                                GT|I(?:acute|circ|grave|uml)|LT|Ntilde|
                                O(?:acute|circ|grave|slash|tilde|uml)|QUOT|REG|THORN|
                                U(?:acute|circ|grave|uml)|Yacute|
                                a(?:acute|c(?:irc|ute)|elig|grave|mp|ring|tilde|uml)|brvbar|
                                c(?:cedil|edil|urren)|cent(?!erdot;)|copy(?!sr;)|deg|
                                divide(?!ontimes;)|e(?:acute|circ|grave|th|uml)|
                                frac(?:1(?:2|4)|34)|
                                gt(?!c(?:c|ir)|dot|lPar|quest|r(?:a(?:pprox|rr)|dot|eq(?:less|qless)|less|sim);)|
                                i(?:acute|circ|excl|grave|quest|uml)|laquo|
                                lt(?!c(?:c|ir)|dot|hree|imes|larr|quest|r(?:Par|i(?:e|f|));)|
                                m(?:acr|i(?:cro|ddot))|n(?:bsp|tilde)|
                                not(?!in(?:E|dot|v(?:a|b|c)|)|ni(?:v(?:a|b|c)|);)|
                                o(?:acute|circ|grave|rd(?:f|m)|slash|tilde|uml)|
                                p(?:lusmn|ound)|para(?!llel;)|quot|r(?:aquo|eg)|
                                s(?:ect|hy|up(?:1|2|3)|zlig)|thorn|times(?!b(?:ar|)|d;)|
                                u(?:acute|circ|grave|ml|uml)|y(?:acute|en|uml)
                        )
                        (?:[^;]|$))     #  b. and not followed by a semicolon
                        # S = study, for efficiency
                        /Sx", '&amp;', $tooltip );
                $tooltip = Sanitizer::stripAllTags( $tooltip );

                return $tooltip;
        }

        /**
         * Callback from the Sanitizer for expanding items found in HTML attribute
         * values, so they can be safely tested and escaped.
         *
         * @param string &$text
         * @param PPFrame|false $frame
         * @return string
         * @deprecated since 1.35, internal callback should not have been public
         */
        public function attributeStripCallback( &$text, $frame = false ) {
                wfDeprecated( __METHOD__, '1.35' );
                $text = $this->replaceVariables( $text, $frame );
                $text = $this->mStripState->unstripBoth( $text );
                return $text;
        }

        /**
         * Accessor
         *
         * @return array
         * @since 1.6
         */
        public function getTags(): array {
                return array_keys( $this->mTagHooks );
        }

        /**
         * @since 1.32
         * @return array
         */
        public function getFunctionSynonyms() {
                return $this->mFunctionSynonyms;
        }

        /**
         * @since 1.32
         * @return string
         */
        public function getUrlProtocols() {
                return $this->urlUtils->validProtocols();
        }

        /**
         * Break wikitext input into sections, and either pull or replace
         * some particular section's text.
         *
         * External callers should use the getSection and replaceSection methods.
         *
         * @param string $text Page wikitext
         * @param string|int $sectionId A section identifier string of the form:
         *   "<flag1> - <flag2> - ... - <section number>"
         *
         * Currently the only recognised flag is "T", which means the target section number
         * was derived during a template inclusion parse, in other words this is a template
         * section edit link. If no flags are given, it was an ordinary section edit link.
         * This flag is required to avoid a section numbering mismatch when a section is
         * enclosed by "<includeonly>" (T8563).
         *
         * The section number 0 pulls the text before the first heading; other numbers will
         * pull the given section along with its lower-level subsections. If the section is
         * not found, $mode=get will return $newtext, and $mode=replace will return $text.
         *
         * Section 0 is always considered to exist, even if it only contains the empty
         * string. If $text is the empty string and section 0 is replaced, $newText is
         * returned.
         *
         * @param string $mode One of "get" or "replace"
         * @param string|false $newText Replacement text for section data.
         * @param PageReference|null $page
         * @return string For "get", the extracted section text.
         *   for "replace", the whole page with the section replaced.
         */
        private function extractSections( $text, $sectionId, $mode, $newText, ?PageReference $page = null ) {
                $magicScopeVariable = $this->lock();
                $this->startParse(
                        $page,
                        ParserOptions::newFromUser( RequestContext::getMain()->getUser() ),
                        self::OT_PLAIN,
                        true
                );
                $outText = '';
                $frame = $this->getPreprocessor()->newFrame();

                # Process section extraction flags
                $flags = 0;
                $sectionParts = explode( '-', $sectionId );
                // The section ID may either be a magic string such as 'new' (which should be treated as 0),
                // or a numbered section ID in the format of "T-<section index>".
                // Explicitly coerce the section index into a number accordingly. (T323373)
                $sectionIndex = (int)array_pop( $sectionParts );
                foreach ( $sectionParts as $part ) {
                        if ( $part === 'T' ) {
                                $flags |= Preprocessor::DOM_FOR_INCLUSION;
                        }
                }

                # Check for empty input
                if ( strval( $text ) === '' ) {
                        # Only sections 0 and T-0 exist in an empty document
                        if ( $sectionIndex === 0 ) {
                                if ( $mode === 'get' ) {
                                        return '';
                                }

                                return $newText;
                        } else {
                                if ( $mode === 'get' ) {
                                        return $newText;
                                }

                                return $text;
                        }
                }

                # Preprocess the text
                $root = $this->preprocessToDom( $text, $flags );

                # <h> nodes indicate section breaks
                # They can only occur at the top level, so we can find them by iterating the root's children
                $node = $root->getFirstChild();

                # Find the target section
                if ( $sectionIndex === 0 ) {
                        # Section zero doesn't nest, level=big
                        $targetLevel = 1000;
                } else {
                        while ( $node ) {
                                if ( $node->getName() === 'h' ) {
                                        $bits = $node->splitHeading();
                                        if ( $bits['i'] == $sectionIndex ) {
                                                $targetLevel = $bits['level'];
                                                break;
                                        }
                                }
                                if ( $mode === 'replace' ) {
                                        $outText .= $frame->expand( $node, PPFrame::RECOVER_ORIG );
                                }
                                $node = $node->getNextSibling();
                        }
                }

                if ( !$node ) {
                        # Not found
                        if ( $mode === 'get' ) {
                                return $newText;
                        } else {
                                return $text;
                        }
                }

                # Find the end of the section, including nested sections
                do {
                        if ( $node->getName() === 'h' ) {
                                $bits = $node->splitHeading();
                                $curLevel = $bits['level'];
                                // @phan-suppress-next-line PhanPossiblyUndeclaredVariable False positive
                                if ( $bits['i'] != $sectionIndex && $curLevel <= $targetLevel ) {
                                        break;
                                }
                        }
                        if ( $mode === 'get' ) {
                                $outText .= $frame->expand( $node, PPFrame::RECOVER_ORIG );
                        }
                        $node = $node->getNextSibling();
                } while ( $node );

                # Write out the remainder (in replace mode only)
                if ( $mode === 'replace' ) {
                        # Output the replacement text
                        # Add two newlines on -- trailing whitespace in $newText is conventionally
                        # stripped by the editor, so we need both newlines to restore the paragraph gap
                        # Only add trailing whitespace if there is newText
                        if ( $newText != "" ) {
                                $outText .= $newText . "\n\n";
                        }

                        while ( $node ) {
                                $outText .= $frame->expand( $node, PPFrame::RECOVER_ORIG );
                                $node = $node->getNextSibling();
                        }
                }

                # Re-insert stripped tags
                $outText = rtrim( $this->mStripState->unstripBoth( $outText ) );

                return $outText;
        }

        /**
         * This function returns the text of a section, specified by a number ($section).
         * A section is text under a heading like == Heading == or \<h1\>Heading\</h1\>, or
         * the first section before any such heading (section 0).
         *
         * If a section contains subsections, these are also returned.
         *
         * @param string $text Text to look in
         * @param string|int $sectionId Section identifier as a number or string
         * (e.g. 0, 1 or 'T-1').
         * @param string|false $defaultText Default to return if section is not found
         *
         * @return string Text of the requested section
         * @since 1.7
         */
        public function getSection( $text, $sectionId, $defaultText = '' ) {
                return $this->extractSections( $text, $sectionId, 'get', $defaultText );
        }

        /**
         * This function returns $oldtext after the content of the section
         * specified by $section has been replaced with $text. If the target
         * section does not exist, $oldtext is returned unchanged.
         *
         * @param string $oldText Former text of the article
         * @param string|int $sectionId Section identifier as a number or string
         * (e.g. 0, 1 or 'T-1').
         * @param string|false $newText Replacing text
         *
         * @return string Modified text
         * @since 1.7
         */
        public function replaceSection( $oldText, $sectionId, $newText ) {
                return $this->extractSections( $oldText, $sectionId, 'replace', $newText );
        }

        /**
         * Get an array of preprocessor section information.
         *
         * Preprocessor sections are those identified by wikitext-style syntax, not
         * HTML-style syntax. Templates are not expanded, so these sections do not
         * include sections created by templates or parser functions. This is the
         * same definition of a section as used by section editing, but not the
         * same as TOC generation.
         *
         * These sections are typically smaller than those acted on by getSection() and
         * replaceSection() since they are not nested. Section nesting could be
         * reconstructed from the heading levels.
         *
         * The return value is an array of associative array info structures. Each
         * associative array contains the following keys, describing a section:
         *
         *  - index: An integer identifying the section.
         *  - level: The heading level, e.g. 1 for <h1>. For the section before the
         *    the first heading, this will be 0.
         *  - offset: The byte offset within the wikitext at which the section starts
         *  - heading: The wikitext for the header which introduces the section,
         *    including equals signs. For the section before the first heading, this
         *    will be an empty string.
         *  - text: The complete text of the section.
         *
         * @param string $text
         * @return array[]
         * @internal
         */
        public function getFlatSectionInfo( $text ) {
                $magicScopeVariable = $this->lock();
                $this->startParse(
                        null,
                        ParserOptions::newFromUser( RequestContext::getMain()->getUser() ),
                        self::OT_PLAIN,
                        true
                );
                $frame = $this->getPreprocessor()->newFrame();
                $root = $this->preprocessToDom( $text, 0 );
                $node = $root->getFirstChild();
                $offset = 0;
                $currentSection = [
                        'index' => 0,
                        'level' => 0,
                        'offset' => 0,
                        'heading' => '',
                        'text' => ''
                ];
                $sections = [];

                while ( $node ) {
                        $nodeText = $frame->expand( $node, PPFrame::RECOVER_ORIG );
                        if ( $node->getName() === 'h' ) {
                                $bits = $node->splitHeading();
                                $sections[] = $currentSection;
                                $currentSection = [
                                        'index' => $bits['i'],
                                        'level' => $bits['level'],
                                        'offset' => $offset,
                                        'heading' => $nodeText,
                                        'text' => $nodeText
                                ];
                        } else {
                                $currentSection['text'] .= $nodeText;
                        }
                        $offset += strlen( $nodeText );
                        $node = $node->getNextSibling();
                }
                $sections[] = $currentSection;
                return $sections;
        }

        /**
         * Get the ID of the revision we are parsing
         *
         * The return value will be either:
         *   - a) Positive, indicating a specific revision ID (current or old)
         *   - b) Zero, meaning the revision ID is specified by getCurrentRevisionRecordCallback()
         *   - c) Null, meaning the parse is for preview mode and there is no revision
         *
         * @return int|null
         * @since 1.13
         */
        public function getRevisionId() {
                return $this->mRevisionId;
        }

        /**
         * Get the revision record object for $this->mRevisionId
         *
         * @return RevisionRecord|null Either a RevisionRecord object or null
         * @since 1.35
         */
        public function getRevisionRecordObject() {
                if ( $this->mRevisionRecordObject ) {
                        return $this->mRevisionRecordObject;
                }

                // NOTE: try to get the RevisionRecord object even if mRevisionId is null.
                // This is useful when parsing a revision that has not yet been saved.
                // However, if we get back a saved revision even though we are in
                // preview mode, we'll have to ignore it, see below.
                // NOTE: This callback may be used to inject an OLD revision that was
                // already loaded, so "current" is a bit of a misnomer. We can't just
                // skip it if mRevisionId is set.
                $rev = call_user_func(
                        $this->mOptions->getCurrentRevisionRecordCallback(),
                        $this->getTitle(),
                        $this
                );

                if ( !$rev ) {
                        // The revision record callback returns `false` (not null) to
                        // indicate that the revision is missing.  (See for example
                        // Parser::statelessFetchRevisionRecord(), the default callback.)
                        // This API expects `null` instead. (T251952)
                        return null;
                }

                if ( $this->mRevisionId === null && $rev->getId() ) {
                        // We are in preview mode (mRevisionId is null), and the current revision callback
                        // returned an existing revision. Ignore it and return null, it's probably the page's
                        // current revision, which is not what we want here. Note that we do want to call the
                        // callback to allow the unsaved revision to be injected here, e.g. for
                        // self-transclusion previews.
                        return null;
                }

                // If the parse is for a new revision, then the callback should have
                // already been set to force the object and should match mRevisionId.
                // If not, try to fetch by mRevisionId instead.
                if ( $this->mRevisionId && $rev->getId() != $this->mRevisionId ) {
                        $rev = MediaWikiServices::getInstance()
                                ->getRevisionLookup()
                                ->getRevisionById( $this->mRevisionId );
                }

                $this->mRevisionRecordObject = $rev;

                return $this->mRevisionRecordObject;
        }

        /**
         * Get the timestamp associated with the current revision, adjusted for
         * the default server-local timestamp
         * @return string TS_MW timestamp
         * @since 1.9
         */
        public function getRevisionTimestamp() {
                if ( $this->mRevisionTimestamp !== null ) {
                        return $this->mRevisionTimestamp;
                }

                # Use specified revision timestamp, falling back to the current timestamp
                $revObject = $this->getRevisionRecordObject();
                $timestamp = $revObject && $revObject->getTimestamp()
                        ? $revObject->getTimestamp()
                        : $this->mOptions->getTimestamp();
                $this->mOutput->setRevisionTimestampUsed( $timestamp ); // unadjusted time zone

                # The cryptic '' timezone parameter tells to use the site-default
                # timezone offset instead of the user settings.
                # Since this value will be saved into the parser cache, served
                # to other users, and potentially even used inside links and such,
                # it needs to be consistent for all visitors.
                $this->mRevisionTimestamp = $this->contLang->userAdjust( $timestamp, '' );

                return $this->mRevisionTimestamp;
        }

        /**
         * Get the name of the user that edited the last revision
         *
         * @return string|null User name
         * @since 1.15
         */
        public function getRevisionUser(): ?string {
                if ( $this->mRevisionUser === null ) {
                        $revObject = $this->getRevisionRecordObject();

                        # if this template is subst: the revision id will be blank,
                        # so just use the current user's name
                        if ( $revObject && $revObject->getUser() ) {
                                $this->mRevisionUser = $revObject->getUser()->getName();
                        } elseif ( $this->ot['wiki'] || $this->mOptions->getIsPreview() ) {
                                $this->mRevisionUser = $this->getUserIdentity()->getName();
                        } else {
                                # Note that we fall through here with
                                # $this->mRevisionUser still null
                        }
                }
                return $this->mRevisionUser;
        }

        /**
         * Get the size of the revision
         *
         * @return int|null Revision size
         * @since 1.22
         */
        public function getRevisionSize() {
                if ( $this->mRevisionSize === null ) {
                        $revObject = $this->getRevisionRecordObject();

                        # if this variable is subst: the revision id will be blank,
                        # so just use the parser input size, because the own substitution
                        # will change the size.
                        if ( $revObject ) {
                                $this->mRevisionSize = $revObject->getSize();
                        } else {
                                $this->mRevisionSize = $this->mInputSize;
                        }
                }
                return $this->mRevisionSize;
        }

        /**
         * Mutator for the 'defaultsort' page property.
         *
         * @param string $sort New value
         * @since 1.0
         * @deprecated since 1.38, use
         * $parser->getOutput()->setPageProperty('defaultsort', $sort)
         */
        public function setDefaultSort( $sort ) {
                wfDeprecated( __METHOD__, '1.38' );
                $this->mOutput->setPageProperty( 'defaultsort', $sort );
        }

        /**
         * Accessor for the 'defaultsort' page property.
         * Will use the empty string if none is set.
         *
         * This value is treated as a prefix, so the
         * empty string is equivalent to sorting by
         * page name.
         *
         * @return string
         * @since 1.9
         * @deprecated since 1.38, use
         * $parser->getOutput()->getPageProperty('defaultsort') ?? ''
         */
        public function getDefaultSort() {
                wfDeprecated( __METHOD__, '1.38' );
                return $this->mOutput->getPageProperty( 'defaultsort' ) ?? '';
        }

        /**
         * Accessor for the 'defaultsort' page property.
         * Unlike getDefaultSort(), will return false if none is set
         *
         * @return string|false
         * @since 1.14
         * @deprecated since 1.38, use
         * $parser->getOutput()->getPageProperty('defaultsort') ?? false
         */
        public function getCustomDefaultSort() {
                wfDeprecated( __METHOD__, '1.38' );
                return $this->mOutput->getPageProperty( 'defaultsort' ) ?? false;
        }

        private static function getSectionNameFromStrippedText( $text ) {
                $text = Sanitizer::normalizeSectionNameWhitespace( $text );
                $text = Sanitizer::decodeCharReferences( $text );
                $text = self::normalizeSectionName( $text );
                return $text;
        }

        private static function makeAnchor( $sectionName ) {
                return '#' . Sanitizer::escapeIdForLink( $sectionName );
        }

        private function makeLegacyAnchor( $sectionName ) {
                $fragmentMode = $this->svcOptions->get( MainConfigNames::FragmentMode );
                if ( isset( $fragmentMode[1] ) && $fragmentMode[1] === 'legacy' ) {
                        // ForAttribute() and ForLink() are the same for legacy encoding
                        $id = Sanitizer::escapeIdForAttribute( $sectionName, Sanitizer::ID_FALLBACK );
                } else {
                        $id = Sanitizer::escapeIdForLink( $sectionName );
                }

                return "#$id";
        }

        /**
         * Try to guess the section anchor name based on a wikitext fragment
         * presumably extracted from a heading, for example "Header" from
         * "== Header ==".
         *
         * @param string $text
         * @return string Anchor (starting with '#')
         * @since 1.12
         */
        public function guessSectionNameFromWikiText( $text ) {
                # Strip out wikitext links(they break the anchor)
                $text = $this->stripSectionName( $text );
                $sectionName = self::getSectionNameFromStrippedText( $text );
                return self::makeAnchor( $sectionName );
        }

        /**
         * Same as guessSectionNameFromWikiText(), but produces legacy anchors
         * instead, if possible. For use in redirects, since various versions
         * of Microsoft browsers interpret Location: headers as something other
         * than UTF-8, resulting in breakage.
         *
         * @param string $text The section name
         * @return string Anchor (starting with '#')
         * @since 1.17
         */
        public function guessLegacySectionNameFromWikiText( $text ) {
                # Strip out wikitext links(they break the anchor)
                $text = $this->stripSectionName( $text );
                $sectionName = self::getSectionNameFromStrippedText( $text );
                return $this->makeLegacyAnchor( $sectionName );
        }

        /**
         * Like guessSectionNameFromWikiText(), but takes already-stripped text as input.
         * @param string $text Section name (plain text)
         * @return string Anchor (starting with '#')
         * @since 1.31
         */
        public static function guessSectionNameFromStrippedText( $text ) {
                $sectionName = self::getSectionNameFromStrippedText( $text );
                return self::makeAnchor( $sectionName );
        }

        /**
         * Apply the same normalization as code making links to this section would
         *
         * @param string $text
         * @return string
         */
        private static function normalizeSectionName( $text ) {
                # T90902: ensure the same normalization is applied for IDs as to links
                /** @var MediaWikiTitleCodec $titleParser */
                $titleParser = MediaWikiServices::getInstance()->getTitleParser();
                '@phan-var MediaWikiTitleCodec $titleParser';
                try {

                        $parts = $titleParser->splitTitleString( "#$text" );
                } catch ( MalformedTitleException $ex ) {
                        return $text;
                }
                return $parts['fragment'];
        }

        /**
         * Strips a text string of wikitext for use in a section anchor
         *
         * Accepts a text string and then removes all wikitext from the
         * string and leaves only the resultant text (i.e. the result of
         * [[User:WikiSysop|Sysop]] would be "Sysop" and the result of
         * [[User:WikiSysop]] would be "User:WikiSysop") - this is intended
         * to create valid section anchors by mimicking the output of the
         * parser when headings are parsed.
         *
         * @param string $text Text string to be stripped of wikitext
         * for use in a Section anchor
         * @return string Filtered text string
         * @since 1.12
         */
        public function stripSectionName( $text ) {
                # Strip internal link markup
                $text = preg_replace( '/\[\[:?([^[|]+)\|([^[]+)\]\]/', '$2', $text );
                $text = preg_replace( '/\[\[:?([^[]+)\|?\]\]/', '$1', $text );

                # Strip external link markup
                # @todo FIXME: Not tolerant to blank link text
                # I.E. [https://www.mediawiki.org] will render as [1] or something depending
                # on how many empty links there are on the page - need to figure that out.
                $text = preg_replace(
                        '/\[(?i:' . $this->urlUtils->validProtocols() . ')([^ ]+?) ([^[]+)\]/', '$2', $text );

                # Parse wikitext quotes (italics & bold)
                $text = $this->doQuotes( $text );

                # Strip HTML tags
                $text = StringUtils::delimiterReplace( '<', '>', '', $text );
                return $text;
        }

        /**
         * Call a callback function on all regions of the given text that are not
         * inside strip markers, and replace those regions with the return value
         * of the callback. For example, with input:
         *
         *  aaa<MARKER>bbb
         *
         * This will call the callback function twice, with 'aaa' and 'bbb'. Those
         * two strings will be replaced with the value returned by the callback in
         * each case.
         *
         * @param string $s
         * @param callable $callback
         *
         * @return string
         * @internal
         * @since 1.12
         */
        public function markerSkipCallback( $s, callable $callback ) {
                $i = 0;
                $out = '';
                while ( $i < strlen( $s ) ) {
                        $markerStart = strpos( $s, self::MARKER_PREFIX, $i );
                        if ( $markerStart === false ) {
                                $out .= call_user_func( $callback, substr( $s, $i ) );
                                break;
                        } else {
                                $out .= call_user_func( $callback, substr( $s, $i, $markerStart - $i ) );
                                $markerEnd = strpos( $s, self::MARKER_SUFFIX, $markerStart );
                                if ( $markerEnd === false ) {
                                        $out .= substr( $s, $markerStart );
                                        break;
                                } else {
                                        $markerEnd += strlen( self::MARKER_SUFFIX );
                                        $out .= substr( $s, $markerStart, $markerEnd - $markerStart );
                                        $i = $markerEnd;
                                }
                        }
                }
                return $out;
        }

        /**
         * Remove any strip markers found in the given text.
         *
         * @param string $text
         * @return string
         * @since 1.19
         */
        public function killMarkers( $text ) {
                return $this->mStripState->killMarkers( $text );
        }

        /**
         * Parsed a width param of imagelink like 300px or 200x300px
         *
         * @param string $value
         * @param bool $parseHeight
         *
         * @return array
         * @since 1.20
         * @internal
         */
        public static function parseWidthParam( $value, $parseHeight = true ) {
                $parsedWidthParam = [];
                if ( $value === '' ) {
                        return $parsedWidthParam;
                }
                $m = [];
                # (T15500) In both cases (width/height and width only),
                # permit trailing "px" for backward compatibility.
                if ( $parseHeight && preg_match( '/^([0-9]*)x([0-9]*)\s*(?:px)?\s*$/', $value, $m ) ) {
                        $width = intval( $m[1] );
                        $height = intval( $m[2] );
                        $parsedWidthParam['width'] = $width;
                        $parsedWidthParam['height'] = $height;
                } elseif ( preg_match( '/^[0-9]*\s*(?:px)?\s*$/', $value ) ) {
                        $width = intval( $value );
                        $parsedWidthParam['width'] = $width;
                }
                return $parsedWidthParam;
        }

        /**
         * Lock the current instance of the parser.
         *
         * This is meant to stop someone from calling the parser
         * recursively and messing up all the strip state.
         *
         * @throws MWException If parser is in a parse
         * @return ScopedCallback The lock will be released once the return value goes out of scope.
         */
        protected function lock() {
                if ( $this->mInParse ) {
                        throw new MWException( "Parser state cleared while parsing. "
                                . "Did you call Parser::parse recursively? Lock is held by: " . $this->mInParse );
                }

                // Save the backtrace when locking, so that if some code tries locking again,
                // we can print the lock owner's backtrace for easier debugging
                $e = new Exception;
                $this->mInParse = $e->getTraceAsString();

                $recursiveCheck = new ScopedCallback( function () {
                        $this->mInParse = false;
                } );

                return $recursiveCheck;
        }

        /**
         * Will entry points such as parse() throw an exception due to the parser
         * already being active?
         *
         * @since 1.39
         * @return bool
         */
        public function isLocked() {
                return (bool)$this->mInParse;
        }

        /**
         * Strip outer <p></p> tag from the HTML source of a single paragraph.
         *
         * Returns original HTML if the <p/> tag has any attributes, if there's no wrapping <p/> tag,
         * or if there is more than one <p/> tag in the input HTML.
         *
         * @param string $html
         * @return string
         * @since 1.24
         */
        public static function stripOuterParagraph( $html ) {
                $m = [];
                if ( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $html, $m ) && strpos( $m[1], '</p>' ) === false ) {
                        $html = $m[1];
                }

                return $html;
        }

        /**
         * Add HTML tags marking the parts of a page title, to be displayed in the first heading of the page.
         *
         * @internal
         * @since 1.39
         * @param string|HtmlArmor $nsText
         * @param string|HtmlArmor $nsSeparator
         * @param string|HtmlArmor $mainText
         * @return string HTML
         */
        public static function formatPageTitle( $nsText, $nsSeparator, $mainText ): string {
                $html = '';
                if ( $nsText !== '' ) {
                        $html .= '<span class="mw-page-title-namespace">' . HtmlArmor::getHtml( $nsText ) . '</span>';
                        $html .= '<span class="mw-page-title-separator">' . HtmlArmor::getHtml( $nsSeparator ) . '</span>';
                }
                $html .= '<span class="mw-page-title-main">' . HtmlArmor::getHtml( $mainText ) . '</span>';
                return $html;
        }

        /**
         * Return this parser if it is not doing anything, otherwise
         * get a fresh parser. You can use this method by doing
         * $newParser = $oldParser->getFreshParser(), or more simply
         * $oldParser->getFreshParser()->parse( ... );
         * if you're unsure if $oldParser is safe to use.
         *
         * @deprecated since 1.39, use ParserFactory::getInstance(), Hard-deprecated since 1.41.
         * @since 1.24
         * @return Parser A parser object that is not parsing anything
         */
        public function getFreshParser() {
                wfDeprecated( __METHOD__, '1.39' );
                if ( $this->mInParse ) {
                        return $this->factory->create();
                } else {
                        return $this;
                }
        }

        /**
         * Set's up the PHP implementation of OOUI for use in this request
         * and instructs OutputPage to enable OOUI for itself.
         *
         * @since 1.26
         * @deprecated since 1.35, use $parser->getOutput()->setEnableOOUI() instead.
         */
        public function enableOOUI() {
                wfDeprecated( __METHOD__, '1.35' );
                OutputPage::setupOOUI();
                $this->mOutput->setEnableOOUI( true );
        }

        /**
         * Sets the flag on the parser output but also does some debug logging.
         * Note that there is a copy of this method in CoreMagicVariables as well.
         * @param string $flag
         * @param string $reason
         */
        private function setOutputFlag( string $flag, string $reason ): void {
                $this->mOutput->setOutputFlag( $flag );
                $name = $this->getTitle()->getPrefixedText();
                $this->logger->debug( __METHOD__ . ": set $flag flag on '$name'; $reason" );
        }
}