ApiParse.php

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<?php
use MediaWiki\MediaWikiServices;

class ApiParse extends ApiBase {

    private $section = null;

    private $content = null;

    private $pstContent = null;

    private $contentIsDeleted = false, $contentIsSuppressed = false;

    public function execute() {
        // The data is hot but user-dependent, like page views, so we set vary cookies
        $this->getMain()->setCacheMode( 'anon-public-user-private' );

        // Get parameters
        $params = $this->extractRequestParams();

        // No easy way to say that text and title or revid are allowed together
        // while the rest aren't, so just do it in three calls.
        $this->requireMaxOneParameter( $params, 'page', 'pageid', 'oldid', 'text' );
        $this->requireMaxOneParameter( $params, 'page', 'pageid', 'oldid', 'title' );
        $this->requireMaxOneParameter( $params, 'page', 'pageid', 'oldid', 'revid' );

        $text = $params['text'];
        $title = $params['title'];
        if ( $title === null ) {
            $titleProvided = false;
            // A title is needed for parsing, so arbitrarily choose one
            $title = 'API';
        } else {
            $titleProvided = true;
        }

        $page = $params['page'];
        $pageid = $params['pageid'];
        $oldid = $params['oldid'];

        $model = $params['contentmodel'];
        $format = $params['contentformat'];

        $prop = array_flip( $params['prop'] );

        if ( isset( $params['section'] ) ) {
            $this->section = $params['section'];
            if ( !preg_match( '/^((T-)?\d+|new)$/', $this->section ) ) {
                $this->dieWithError( 'apierror-invalidsection' );
            }
        } else {
            $this->section = false;
        }

        // The parser needs $wgTitle to be set, apparently the
        // $title parameter in Parser::parse isn't enough *sigh*
        // TODO: Does this still need $wgTitle?
        global $wgParser, $wgTitle;

        $redirValues = null;

        $needContent = isset( $prop['wikitext'] ) ||
            isset( $prop['parsetree'] ) || $params['generatexml'];

        // Return result
        $result = $this->getResult();

        if ( !is_null( $oldid ) || !is_null( $pageid ) || !is_null( $page ) ) {
            if ( $this->section === 'new' ) {
                $this->dieWithError( 'apierror-invalidparammix-parse-new-section', 'invalidparammix' );
            }
            if ( !is_null( $oldid ) ) {
                // Don't use the parser cache
                $rev = Revision::newFromId( $oldid );
                if ( !$rev ) {
                    $this->dieWithError( [ 'apierror-nosuchrevid', $oldid ] );
                }

                $this->checkTitleUserPermissions( $rev->getTitle(), 'read' );
                if ( !$rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
                    $this->dieWithError(
                        [ 'apierror-permissiondenied', $this->msg( 'action-deletedtext' ) ]
                    );
                }

                $titleObj = $rev->getTitle();
                $wgTitle = $titleObj;
                $pageObj = WikiPage::factory( $titleObj );
                list( $popts, $reset, $suppressCache ) = $this->makeParserOptions( $pageObj, $params );
                $p_result = $this->getParsedContent(
                    $pageObj, $popts, $suppressCache, $pageid, $rev, $needContent
                );
            } else { // Not $oldid, but $pageid or $page
                if ( $params['redirects'] ) {
                    $reqParams = [
                        'redirects' => '',
                    ];
                    if ( !is_null( $pageid ) ) {
                        $reqParams['pageids'] = $pageid;
                    } else { // $page
                        $reqParams['titles'] = $page;
                    }
                    $req = new FauxRequest( $reqParams );
                    $main = new ApiMain( $req );
                    $pageSet = new ApiPageSet( $main );
                    $pageSet->execute();
                    $redirValues = $pageSet->getRedirectTitlesAsResult( $this->getResult() );

                    $to = $page;
                    foreach ( $pageSet->getRedirectTitles() as $title ) {
                        $to = $title->getFullText();
                    }
                    $pageParams = [ 'title' => $to ];
                } elseif ( !is_null( $pageid ) ) {
                    $pageParams = [ 'pageid' => $pageid ];
                } else { // $page
                    $pageParams = [ 'title' => $page ];
                }

                $pageObj = $this->getTitleOrPageId( $pageParams, 'fromdb' );
                $titleObj = $pageObj->getTitle();
                if ( !$titleObj || !$titleObj->exists() ) {
                    $this->dieWithError( 'apierror-missingtitle' );
                }

                $this->checkTitleUserPermissions( $titleObj, 'read' );
                $wgTitle = $titleObj;

                if ( isset( $prop['revid'] ) ) {
                    $oldid = $pageObj->getLatest();
                }

                list( $popts, $reset, $suppressCache ) = $this->makeParserOptions( $pageObj, $params );
                $p_result = $this->getParsedContent(
                    $pageObj, $popts, $suppressCache, $pageid, null, $needContent
                );
            }
        } else { // Not $oldid, $pageid, $page. Hence based on $text
            $titleObj = Title::newFromText( $title );
            if ( !$titleObj || $titleObj->isExternal() ) {
                $this->dieWithError( [ 'apierror-invalidtitle', wfEscapeWikiText( $title ) ] );
            }
            $revid = $params['revid'];
            if ( $revid !== null ) {
                $rev = Revision::newFromId( $revid );
                if ( !$rev ) {
                    $this->dieWithError( [ 'apierror-nosuchrevid', $revid ] );
                }
                $pTitleObj = $titleObj;
                $titleObj = $rev->getTitle();
                if ( $titleProvided ) {
                    if ( !$titleObj->equals( $pTitleObj ) ) {
                        $this->addWarning( [ 'apierror-revwrongpage', $rev->getId(),
                            wfEscapeWikiText( $pTitleObj->getPrefixedText() ) ] );
                    }
                } else {
                    // Consider the title derived from the revid as having
                    // been provided.
                    $titleProvided = true;
                }
            }
            $wgTitle = $titleObj;
            if ( $titleObj->canExist() ) {
                $pageObj = WikiPage::factory( $titleObj );
            } else {
                // Do like MediaWiki::initializeArticle()
                $article = Article::newFromTitle( $titleObj, $this->getContext() );
                $pageObj = $article->getPage();
            }

            list( $popts, $reset ) = $this->makeParserOptions( $pageObj, $params );
            $textProvided = !is_null( $text );

            if ( !$textProvided ) {
                if ( $titleProvided && ( $prop || $params['generatexml'] ) ) {
                    if ( $revid !== null ) {
                        $this->addWarning( 'apiwarn-parse-revidwithouttext' );
                    } else {
                        $this->addWarning( 'apiwarn-parse-titlewithouttext' );
                    }
                }
                // Prevent warning from ContentHandler::makeContent()
                $text = '';
            }

            // If we are parsing text, do not use the content model of the default
            // API title, but default to wikitext to keep BC.
            if ( $textProvided && !$titleProvided && is_null( $model ) ) {
                $model = CONTENT_MODEL_WIKITEXT;
                $this->addWarning( [ 'apiwarn-parse-nocontentmodel', $model ] );
            }

            try {
                $this->content = ContentHandler::makeContent( $text, $titleObj, $model, $format );
            } catch ( MWContentSerializationException $ex ) {
                $this->dieWithException( $ex, [
                    'wrap' => ApiMessage::create( 'apierror-contentserializationexception', 'parseerror' )
                ] );
            }

            if ( $this->section !== false ) {
                if ( $this->section === 'new' ) {
                    // Insert the section title above the content.
                    if ( !is_null( $params['sectiontitle'] ) && $params['sectiontitle'] !== '' ) {
                        $this->content = $this->content->addSectionHeader( $params['sectiontitle'] );
                    }
                } else {
                    $this->content = $this->getSectionContent( $this->content, $titleObj->getPrefixedText() );
                }
            }

            if ( $params['pst'] || $params['onlypst'] ) {
                $this->pstContent = $this->content->preSaveTransform( $titleObj, $this->getUser(), $popts );
            }
            if ( $params['onlypst'] ) {
                // Build a result and bail out
                $result_array = [];
                $result_array['text'] = $this->pstContent->serialize( $format );
                $result_array[ApiResult::META_BC_SUBELEMENTS][] = 'text';
                if ( isset( $prop['wikitext'] ) ) {
                    $result_array['wikitext'] = $this->content->serialize( $format );
                    $result_array[ApiResult::META_BC_SUBELEMENTS][] = 'wikitext';
                }
                if ( !is_null( $params['summary'] ) ||
                    ( !is_null( $params['sectiontitle'] ) && $this->section === 'new' )
                ) {
                    $result_array['parsedsummary'] = $this->formatSummary( $titleObj, $params );
                    $result_array[ApiResult::META_BC_SUBELEMENTS][] = 'parsedsummary';
                }

                $result->addValue( null, $this->getModuleName(), $result_array );

                return;
            }

            // Not cached (save or load)
            if ( $params['pst'] ) {
                $p_result = $this->pstContent->getParserOutput( $titleObj, $revid, $popts );
            } else {
                $p_result = $this->content->getParserOutput( $titleObj, $revid, $popts );
            }
        }

        $result_array = [];

        $result_array['title'] = $titleObj->getPrefixedText();
        $result_array['pageid'] = $pageid ?: $pageObj->getId();
        if ( $this->contentIsDeleted ) {
            $result_array['textdeleted'] = true;
        }
        if ( $this->contentIsSuppressed ) {
            $result_array['textsuppressed'] = true;
        }

        if ( isset( $params['useskin'] ) ) {
            $factory = MediaWikiServices::getInstance()->getSkinFactory();
            $skin = $factory->makeSkin( Skin::normalizeKey( $params['useskin'] ) );
        } else {
            $skin = null;
        }

        $outputPage = null;
        if ( $skin || isset( $prop['headhtml'] ) || isset( $prop['categorieshtml'] ) ) {
            // Enabling the skin via 'useskin', 'headhtml', or 'categorieshtml'
            // gets OutputPage and Skin involved, which (among others) applies
            // these hooks:
            // - ParserOutputHooks
            // - Hook: LanguageLinks
            // - Hook: OutputPageParserOutput
            // - Hook: OutputPageMakeCategoryLinks
            $context = new DerivativeContext( $this->getContext() );
            $context->setTitle( $titleObj );
            $context->setWikiPage( $pageObj );

            if ( $skin ) {
                // Use the skin specified by 'useskin'
                $context->setSkin( $skin );
                // Context clones the skin, refetch to stay in sync. (T166022)
                $skin = $context->getSkin();
            } else {
                // Make sure the context's skin refers to the context. Without this,
                // $outputPage->getSkin()->getOutput() !== $outputPage which
                // confuses some of the output.
                $context->setSkin( $context->getSkin() );
            }

            $outputPage = new OutputPage( $context );
            $outputPage->addParserOutputMetadata( $p_result );
            if ( $this->content ) {
                $outputPage->addContentOverride( $titleObj, $this->content );
            }
            $context->setOutput( $outputPage );

            if ( $skin ) {
                // Based on OutputPage::headElement()
                $skin->setupSkinUserCss( $outputPage );
                // Based on OutputPage::output()
                $outputPage->loadSkinModules( $skin );
            }

            Hooks::run( 'ApiParseMakeOutputPage', [ $this, $outputPage ] );
        }

        if ( !is_null( $oldid ) ) {
            $result_array['revid'] = intval( $oldid );
        }

        if ( $params['redirects'] && !is_null( $redirValues ) ) {
            $result_array['redirects'] = $redirValues;
        }

        if ( isset( $prop['text'] ) ) {
            $result_array['text'] = $p_result->getText( [
                'allowTOC' => !$params['disabletoc'],
                'enableSectionEditLinks' => !$params['disableeditsection'],
                'wrapperDivClass' => $params['wrapoutputclass'],
                'deduplicateStyles' => !$params['disablestylededuplication'],
            ] );
            $result_array[ApiResult::META_BC_SUBELEMENTS][] = 'text';
        }

        if ( !is_null( $params['summary'] ) ||
            ( !is_null( $params['sectiontitle'] ) && $this->section === 'new' )
        ) {
            $result_array['parsedsummary'] = $this->formatSummary( $titleObj, $params );
            $result_array[ApiResult::META_BC_SUBELEMENTS][] = 'parsedsummary';
        }

        if ( isset( $prop['langlinks'] ) ) {
            if ( $skin ) {
                $langlinks = $outputPage->getLanguageLinks();
            } else {
                $langlinks = $p_result->getLanguageLinks();
                // The deprecated 'effectivelanglinks' option depredates OutputPage
                // support via 'useskin'. If not already applied, then run just this
                // one hook of OutputPage::addParserOutputMetadata here.
                if ( $params['effectivelanglinks'] ) {
                    $linkFlags = [];
                    Hooks::run( 'LanguageLinks', [ $titleObj, &$langlinks, &$linkFlags ] );
                }
            }

            $result_array['langlinks'] = $this->formatLangLinks( $langlinks );
        }
        if ( isset( $prop['categories'] ) ) {
            $result_array['categories'] = $this->formatCategoryLinks( $p_result->getCategories() );
        }
        if ( isset( $prop['categorieshtml'] ) ) {
            $result_array['categorieshtml'] = $outputPage->getSkin()->getCategories();
            $result_array[ApiResult::META_BC_SUBELEMENTS][] = 'categorieshtml';
        }
        if ( isset( $prop['links'] ) ) {
            $result_array['links'] = $this->formatLinks( $p_result->getLinks() );
        }
        if ( isset( $prop['templates'] ) ) {
            $result_array['templates'] = $this->formatLinks( $p_result->getTemplates() );
        }
        if ( isset( $prop['images'] ) ) {
            $result_array['images'] = array_keys( $p_result->getImages() );
        }
        if ( isset( $prop['externallinks'] ) ) {
            $result_array['externallinks'] = array_keys( $p_result->getExternalLinks() );
        }
        if ( isset( $prop['sections'] ) ) {
            $result_array['sections'] = $p_result->getSections();
        }
        if ( isset( $prop['parsewarnings'] ) ) {
            $result_array['parsewarnings'] = $p_result->getWarnings();
        }

        if ( isset( $prop['displaytitle'] ) ) {
            $result_array['displaytitle'] = $p_result->getDisplayTitle() !== false
                ? $p_result->getDisplayTitle() : $titleObj->getPrefixedText();
        }

        if ( isset( $prop['headitems'] ) ) {
            if ( $skin ) {
                $result_array['headitems'] = $this->formatHeadItems( $outputPage->getHeadItemsArray() );
            } else {
                $result_array['headitems'] = $this->formatHeadItems( $p_result->getHeadItems() );
            }
        }

        if ( isset( $prop['headhtml'] ) ) {
            $result_array['headhtml'] = $outputPage->headElement( $context->getSkin() );
            $result_array[ApiResult::META_BC_SUBELEMENTS][] = 'headhtml';
        }

        if ( isset( $prop['modules'] ) ) {
            if ( $skin ) {
                $result_array['modules'] = $outputPage->getModules();
                $result_array['modulescripts'] = $outputPage->getModuleScripts();
                $result_array['modulestyles'] = $outputPage->getModuleStyles();
            } else {
                $result_array['modules'] = array_values( array_unique( $p_result->getModules() ) );
                $result_array['modulescripts'] = array_values( array_unique( $p_result->getModuleScripts() ) );
                $result_array['modulestyles'] = array_values( array_unique( $p_result->getModuleStyles() ) );
            }
        }

        if ( isset( $prop['jsconfigvars'] ) ) {
            $jsconfigvars = $skin ? $outputPage->getJsConfigVars() : $p_result->getJsConfigVars();
            $result_array['jsconfigvars'] = ApiResult::addMetadataToResultVars( $jsconfigvars );
        }

        if ( isset( $prop['encodedjsconfigvars'] ) ) {
            $jsconfigvars = $skin ? $outputPage->getJsConfigVars() : $p_result->getJsConfigVars();
            $result_array['encodedjsconfigvars'] = FormatJson::encode(
                $jsconfigvars,
                false,
                FormatJson::ALL_OK
            );
            $result_array[ApiResult::META_SUBELEMENTS][] = 'encodedjsconfigvars';
        }

        if ( isset( $prop['modules'] ) &&
            !isset( $prop['jsconfigvars'] ) && !isset( $prop['encodedjsconfigvars'] ) ) {
            $this->addWarning( 'apiwarn-moduleswithoutvars' );
        }

        if ( isset( $prop['indicators'] ) ) {
            if ( $skin ) {
                $result_array['indicators'] = (array)$outputPage->getIndicators();
            } else {
                $result_array['indicators'] = (array)$p_result->getIndicators();
            }
            ApiResult::setArrayType( $result_array['indicators'], 'BCkvp', 'name' );
        }

        if ( isset( $prop['iwlinks'] ) ) {
            $result_array['iwlinks'] = $this->formatIWLinks( $p_result->getInterwikiLinks() );
        }

        if ( isset( $prop['wikitext'] ) ) {
            $result_array['wikitext'] = $this->content->serialize( $format );
            $result_array[ApiResult::META_BC_SUBELEMENTS][] = 'wikitext';
            if ( !is_null( $this->pstContent ) ) {
                $result_array['psttext'] = $this->pstContent->serialize( $format );
                $result_array[ApiResult::META_BC_SUBELEMENTS][] = 'psttext';
            }
        }
        if ( isset( $prop['properties'] ) ) {
            $result_array['properties'] = (array)$p_result->getProperties();
            ApiResult::setArrayType( $result_array['properties'], 'BCkvp', 'name' );
        }

        if ( isset( $prop['limitreportdata'] ) ) {
            $result_array['limitreportdata'] =
                $this->formatLimitReportData( $p_result->getLimitReportData() );
        }
        if ( isset( $prop['limitreporthtml'] ) ) {
            $result_array['limitreporthtml'] = EditPage::getPreviewLimitReport( $p_result );
            $result_array[ApiResult::META_BC_SUBELEMENTS][] = 'limitreporthtml';
        }

        if ( isset( $prop['parsetree'] ) || $params['generatexml'] ) {
            if ( $this->content->getModel() != CONTENT_MODEL_WIKITEXT ) {
                $this->dieWithError( 'apierror-parsetree-notwikitext', 'notwikitext' );
            }

            $wgParser->startExternalParse( $titleObj, $popts, Parser::OT_PREPROCESS );
            $xml = $wgParser->preprocessToDom( $this->content->getNativeData() )->__toString();
            $result_array['parsetree'] = $xml;
            $result_array[ApiResult::META_BC_SUBELEMENTS][] = 'parsetree';
        }

        $result_mapping = [
            'redirects' => 'r',
            'langlinks' => 'll',
            'categories' => 'cl',
            'links' => 'pl',
            'templates' => 'tl',
            'images' => 'img',
            'externallinks' => 'el',
            'iwlinks' => 'iw',
            'sections' => 's',
            'headitems' => 'hi',
            'modules' => 'm',
            'indicators' => 'ind',
            'modulescripts' => 'm',
            'modulestyles' => 'm',
            'properties' => 'pp',
            'limitreportdata' => 'lr',
            'parsewarnings' => 'pw'
        ];
        $this->setIndexedTagNames( $result_array, $result_mapping );
        $result->addValue( null, $this->getModuleName(), $result_array );
    }

    protected function makeParserOptions( WikiPage $pageObj, array $params ) {
        $popts = $pageObj->makeParserOptions( $this->getContext() );
        $popts->enableLimitReport( !$params['disablepp'] && !$params['disablelimitreport'] );
        $popts->setIsPreview( $params['preview'] || $params['sectionpreview'] );
        $popts->setIsSectionPreview( $params['sectionpreview'] );
        if ( $params['disabletidy'] ) {
            $popts->setTidy( false );
        }
        if ( $params['wrapoutputclass'] !== '' ) {
            $popts->setWrapOutputClass( $params['wrapoutputclass'] );
        }

        $reset = null;
        $suppressCache = false;
        Hooks::run( 'ApiMakeParserOptions',
            [ $popts, $pageObj->getTitle(), $params, $this, &$reset, &$suppressCache ] );

        // Force cache suppression when $popts aren't cacheable.
        $suppressCache = $suppressCache || !$popts->isSafeToCache();

        return [ $popts, $reset, $suppressCache ];
    }

    private function getParsedContent(
        WikiPage $page, $popts, $suppressCache, $pageId, $rev, $getContent
    ) {
        $revId = $rev ? $rev->getId() : null;
        $isDeleted = $rev && $rev->isDeleted( Revision::DELETED_TEXT );

        if ( $getContent || $this->section !== false || $isDeleted ) {
            if ( $rev ) {
                $this->content = $rev->getContent( Revision::FOR_THIS_USER, $this->getUser() );
                if ( !$this->content ) {
                    $this->dieWithError( [ 'apierror-missingcontent-revid', $revId ] );
                }
            } else {
                $this->content = $page->getContent( Revision::FOR_THIS_USER, $this->getUser() );
                if ( !$this->content ) {
                    $this->dieWithError( [ 'apierror-missingcontent-pageid', $page->getId() ] );
                }
            }
            $this->contentIsDeleted = $isDeleted;
            $this->contentIsSuppressed = $rev &&
                $rev->isDeleted( Revision::DELETED_TEXT | Revision::DELETED_RESTRICTED );
        }

        if ( $this->section !== false ) {
            $this->content = $this->getSectionContent(
                $this->content,
                $pageId === null ? $page->getTitle()->getPrefixedText() : $this->msg( 'pageid', $pageId )
            );
            return $this->content->getParserOutput( $page->getTitle(), $revId, $popts );
        }

        if ( $isDeleted ) {
            // getParserOutput can't do revdeled revisions
            $pout = $this->content->getParserOutput( $page->getTitle(), $revId, $popts );
        } else {
            // getParserOutput will save to Parser cache if able
            $pout = $page->getParserOutput( $popts, $revId, $suppressCache );
        }
        if ( !$pout ) {
            $this->dieWithError( [ 'apierror-nosuchrevid', $revId ?: $page->getLatest() ] ); // @codeCoverageIgnore
        }

        return $pout;
    }

    private function getSectionContent( Content $content, $what ) {
        // Not cached (save or load)
        $section = $content->getSection( $this->section );
        if ( $section === false ) {
            $this->dieWithError( [ 'apierror-nosuchsection-what', $this->section, $what ], 'nosuchsection' );
        }
        if ( $section === null ) {
            $this->dieWithError( [ 'apierror-sectionsnotsupported-what', $what ], 'nosuchsection' );
            $section = false;
        }

        return $section;
    }

    private function formatSummary( $title, $params ) {
        global $wgParser;
        $summary = !is_null( $params['summary'] ) ? $params['summary'] : '';
        $sectionTitle = !is_null( $params['sectiontitle'] ) ? $params['sectiontitle'] : '';

        if ( $this->section === 'new' && ( $sectionTitle === '' || $summary === '' ) ) {
            if ( $sectionTitle !== '' ) {
                $summary = $params['sectiontitle'];
            }
            if ( $summary !== '' ) {
                $summary = wfMessage( 'newsectionsummary' )
                    ->rawParams( $wgParser->stripSectionName( $summary ) )
                        ->inContentLanguage()->text();
            }
        }
        return Linker::formatComment( $summary, $title, $this->section === 'new' );
    }

    private function formatLangLinks( $links ) {
        $result = [];
        foreach ( $links as $link ) {
            $entry = [];
            $bits = explode( ':', $link, 2 );
            $title = Title::newFromText( $link );

            $entry['lang'] = $bits[0];
            if ( $title ) {
                $entry['url'] = wfExpandUrl( $title->getFullURL(), PROTO_CURRENT );
                // localised language name in 'uselang' language
                $entry['langname'] = Language::fetchLanguageName(
                    $title->getInterwiki(),
                    $this->getLanguage()->getCode()
                );

                // native language name
                $entry['autonym'] = Language::fetchLanguageName( $title->getInterwiki() );
            }
            ApiResult::setContentValue( $entry, 'title', $bits[1] );
            $result[] = $entry;
        }

        return $result;
    }

    private function formatCategoryLinks( $links ) {
        $result = [];

        if ( !$links ) {
            return $result;
        }

        // Fetch hiddencat property
        $lb = new LinkBatch;
        $lb->setArray( [ NS_CATEGORY => $links ] );
        $db = $this->getDB();
        $res = $db->select( [ 'page', 'page_props' ],
            [ 'page_title', 'pp_propname' ],
            $lb->constructSet( 'page', $db ),
            __METHOD__,
            [],
            [ 'page_props' => [
                'LEFT JOIN', [ 'pp_propname' => 'hiddencat', 'pp_page = page_id' ]
            ] ]
        );
        $hiddencats = [];
        foreach ( $res as $row ) {
            $hiddencats[$row->page_title] = isset( $row->pp_propname );
        }

        $linkCache = MediaWikiServices::getInstance()->getLinkCache();

        foreach ( $links as $link => $sortkey ) {
            $entry = [];
            $entry['sortkey'] = $sortkey;
            // array keys will cast numeric category names to ints, so cast back to string
            ApiResult::setContentValue( $entry, 'category', (string)$link );
            if ( !isset( $hiddencats[$link] ) ) {
                $entry['missing'] = true;

                // We already know the link doesn't exist in the database, so
                // tell LinkCache that before calling $title->isKnown().
                $title = Title::makeTitle( NS_CATEGORY, $link );
                $linkCache->addBadLinkObj( $title );
                if ( $title->isKnown() ) {
                    $entry['known'] = true;
                }
            } elseif ( $hiddencats[$link] ) {
                $entry['hidden'] = true;
            }
            $result[] = $entry;
        }

        return $result;
    }

    private function formatLinks( $links ) {
        $result = [];
        foreach ( $links as $ns => $nslinks ) {
            foreach ( $nslinks as $title => $id ) {
                $entry = [];
                $entry['ns'] = $ns;
                ApiResult::setContentValue( $entry, 'title', Title::makeTitle( $ns, $title )->getFullText() );
                $entry['exists'] = $id != 0;
                $result[] = $entry;
            }
        }

        return $result;
    }

    private function formatIWLinks( $iw ) {
        $result = [];
        foreach ( $iw as $prefix => $titles ) {
            foreach ( array_keys( $titles ) as $title ) {
                $entry = [];
                $entry['prefix'] = $prefix;

                $title = Title::newFromText( "{$prefix}:{$title}" );
                if ( $title ) {
                    $entry['url'] = wfExpandUrl( $title->getFullURL(), PROTO_CURRENT );
                }

                ApiResult::setContentValue( $entry, 'title', $title->getFullText() );
                $result[] = $entry;
            }
        }

        return $result;
    }

    private function formatHeadItems( $headItems ) {
        $result = [];
        foreach ( $headItems as $tag => $content ) {
            $entry = [];
            $entry['tag'] = $tag;
            ApiResult::setContentValue( $entry, 'content', $content );
            $result[] = $entry;
        }

        return $result;
    }

    private function formatLimitReportData( $limitReportData ) {
        $result = [];

        foreach ( $limitReportData as $name => $value ) {
            $entry = [];
            $entry['name'] = $name;
            if ( !is_array( $value ) ) {
                $value = [ $value ];
            }
            ApiResult::setIndexedTagNameRecursive( $value, 'param' );
            $entry = array_merge( $entry, $value );
            $result[] = $entry;
        }

        return $result;
    }

    private function setIndexedTagNames( &$array, $mapping ) {
        foreach ( $mapping as $key => $name ) {
            if ( isset( $array[$key] ) ) {
                ApiResult::setIndexedTagName( $array[$key], $name );
            }
        }
    }

    public function getAllowedParams() {
        return [
            'title' => null,
            'text' => [
                ApiBase::PARAM_TYPE => 'text',
            ],
            'revid' => [
                ApiBase::PARAM_TYPE => 'integer',
            ],
            'summary' => null,
            'page' => null,
            'pageid' => [
                ApiBase::PARAM_TYPE => 'integer',
            ],
            'redirects' => false,
            'oldid' => [
                ApiBase::PARAM_TYPE => 'integer',
            ],
            'prop' => [
                ApiBase::PARAM_DFLT => 'text|langlinks|categories|links|templates|' .
                    'images|externallinks|sections|revid|displaytitle|iwlinks|' .
                    'properties|parsewarnings',
                ApiBase::PARAM_ISMULTI => true,
                ApiBase::PARAM_TYPE => [
                    'text',
                    'langlinks',
                    'categories',
                    'categorieshtml',
                    'links',
                    'templates',
                    'images',
                    'externallinks',
                    'sections',
                    'revid',
                    'displaytitle',
                    'headhtml',
                    'modules',
                    'jsconfigvars',
                    'encodedjsconfigvars',
                    'indicators',
                    'iwlinks',
                    'wikitext',
                    'properties',
                    'limitreportdata',
                    'limitreporthtml',
                    'parsetree',
                    'parsewarnings',
                    'headitems',
                ],
                ApiBase::PARAM_HELP_MSG_PER_VALUE => [
                    'parsetree' => [ 'apihelp-parse-paramvalue-prop-parsetree', CONTENT_MODEL_WIKITEXT ],
                ],
                ApiBase::PARAM_DEPRECATED_VALUES => [
                    'headitems' => 'apiwarn-deprecation-parse-headitems',
                ],
            ],
            'wrapoutputclass' => 'mw-parser-output',
            'pst' => false,
            'onlypst' => false,
            'effectivelanglinks' => [
                ApiBase::PARAM_DFLT => false,
                ApiBase::PARAM_DEPRECATED => true,
            ],
            'section' => null,
            'sectiontitle' => [
                ApiBase::PARAM_TYPE => 'string',
            ],
            'disablepp' => [
                ApiBase::PARAM_DFLT => false,
                ApiBase::PARAM_DEPRECATED => true,
            ],
            'disablelimitreport' => false,
            'disableeditsection' => false,
            'disabletidy' => false,
            'disablestylededuplication' => false,
            'generatexml' => [
                ApiBase::PARAM_DFLT => false,
                ApiBase::PARAM_HELP_MSG => [
                    'apihelp-parse-param-generatexml', CONTENT_MODEL_WIKITEXT
                ],
                ApiBase::PARAM_DEPRECATED => true,
            ],
            'preview' => false,
            'sectionpreview' => false,
            'disabletoc' => false,
            'useskin' => [
                ApiBase::PARAM_TYPE => array_keys( Skin::getAllowedSkins() ),
            ],
            'contentformat' => [
                ApiBase::PARAM_TYPE => ContentHandler::getAllContentFormats(),
            ],
            'contentmodel' => [
                ApiBase::PARAM_TYPE => ContentHandler::getContentModels(),
            ]
        ];
    }

    protected function getExamplesMessages() {
        return [
            'action=parse&page=Project:Sandbox'
                => 'apihelp-parse-example-page',
            'action=parse&text={{Project:Sandbox}}&contentmodel=wikitext'
                => 'apihelp-parse-example-text',
            'action=parse&text={{PAGENAME}}&title=Test'
                => 'apihelp-parse-example-texttitle',
            'action=parse&summary=Some+[[link]]&prop='
                => 'apihelp-parse-example-summary',
        ];
    }

    public function getHelpUrls() {
        return 'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Parsing_wikitext#parse';
    }
}