MessageGroupStats.php

<?php
declare( strict_types = 1 );
 
namespace MediaWiki\Extension\Translate\Statistics;
 
use AggregateMessageGroup;
use DeferredUpdates;
use FileBasedMessageGroup;
use MediaWiki\Extension\Translate\MessageGroupProcessing\MessageGroups;
use MediaWiki\Extension\Translate\MessageLoading\MessageCollection;
use MediaWiki\Extension\Translate\MessageLoading\MessageHandle;
use MediaWiki\Extension\Translate\Services;
use MediaWiki\Extension\Translate\Utilities\Utilities;
use MediaWiki\Logger\LoggerFactory;
use MediaWiki\MediaWikiServices;
use MessageGroup;
use stdClass;
use WANObjectCache;
use Wikimedia\Rdbms\Database;
use Wikimedia\Rdbms\IDatabase;
 
class MessageGroupStats {
    private const TABLE = 'translate_groupstats';
    private const LANGUAGE_STATS_KEY = 'translate-all-language-stats';
 
    public const TOTAL = 0; 
    public const TRANSLATED = 1; 
    public const FUZZY = 2; 
    public const PROOFREAD = 3; 
 
    public const FLAG_CACHE_ONLY = 1;
    public const FLAG_NO_CACHE = 2;
    public const FLAG_IMMEDIATE_WRITES = 4;
 
    private static array $updates = [];
    private static ?array $languages = null;
 
    public static function getEmptyStats(): array {
        return [ 0, 0, 0, 0 ];
    }
 
    private static function getUnknownStats(): array {
        return [ null, null, null, null ];
    }
 
    private static function isValidLanguage( string $languageCode ): bool {
        $languages = self::getLanguages();
        return in_array( $languageCode, $languages );
    }
 
    private static function isValidMessageGroup( ?MessageGroup $group ): bool {
        return $group && !MessageGroups::isDynamic( $group );
    }
 
    public static function forItem( string $groupId, string $languageCode, int $flags = 0 ): array {
        $group = MessageGroups::getGroup( $groupId );
        if ( !self::isValidMessageGroup( $group ) || !self::isValidLanguage( $languageCode ) ) {
            return self::getUnknownStats();
        }
 
        $res = self::selectRowsIdLang( [ $groupId ], [ $languageCode ], $flags );
        $stats = self::extractResults( $res, [ $groupId ] );
 
        if ( !isset( $stats[$groupId][$languageCode] ) ) {
            $stats[$groupId][$languageCode] = self::forItemInternal( $stats, $group, $languageCode, $flags );
        }
 
        self::queueUpdates( $flags );
 
        return $stats[$groupId][$languageCode];
    }
 
    public static function forLanguage( string $languageCode, int $flags = 0 ): array {
        if ( !self::isValidLanguage( $languageCode ) ) {
            $stats = [];
            $groups = MessageGroups::singleton()->getGroups();
            $ids = array_keys( $groups );
            foreach ( $ids as $id ) {
                $stats[$id] = self::getUnknownStats();
            }
 
            return $stats;
        }
 
        $stats = self::forLanguageInternal( $languageCode, [], $flags );
        $flattened = [];
        foreach ( $stats as $group => $languages ) {
            $flattened[$group] = $languages[$languageCode];
        }
 
        self::queueUpdates( $flags );
 
        return $flattened;
    }
 
    public static function forGroup( string $groupId, int $flags = 0 ): array {
        $group = MessageGroups::getGroup( $groupId );
        if ( !self::isValidMessageGroup( $group ) ) {
            $languages = self::getLanguages();
            $stats = [];
            foreach ( $languages as $code ) {
                $stats[$code] = self::getUnknownStats();
            }
 
            return $stats;
        }
 
        $stats = self::forGroupInternal( $group, [], $flags );
 
        self::queueUpdates( $flags );
 
        return $stats[$groupId];
    }
 
    public static function clear( MessageHandle $handle ): void {
        $code = $handle->getCode();
        if ( !self::isValidLanguage( $code ) ) {
            return;
        }
        $groups = self::getSortedGroupsForClearing( $handle->getGroupIds() );
        self::internalClearGroups( $code, $groups, 0 );
    }
 
    public static function clearGroup( $id, int $flags = 0 ): void {
        $languages = self::getLanguages();
        $groups = self::getSortedGroupsForClearing( (array)$id );
 
        // Do one language at a time, to save memory
        foreach ( $languages as $code ) {
            self::internalClearGroups( $code, $groups, $flags );
        }
    }
 
    public static function getApproximateLanguageStats(): array {
        $cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
        return $cache->getWithSetCallback(
            self::LANGUAGE_STATS_KEY,
            WANObjectCache::TTL_INDEFINITE,
            function ( $oldValue, &$ttl, array &$setOpts ) {
                $dbr = Utilities::getSafeReadDB();
                $setOpts += Database::getCacheSetOptions( $dbr );
 
                return self::getAllLanguageStats();
            },
            [
                'checkKeys' => [ self::LANGUAGE_STATS_KEY ],
                'pcTTL' => $cache::TTL_PROC_SHORT,
            ]
        );
    }
 
    private static function getAllLanguageStats(): array {
        $dbr = Utilities::getSafeReadDB();
        $res = $dbr->newSelectQueryBuilder()
            ->table( self::TABLE )
            ->select( [
                'tgs_lang',
                'tgs_translated' => 'SUM(tgs_translated)',
                'tgs_fuzzy' => 'SUM(tgs_fuzzy)',
                'tgs_total' => 'SUM(tgs_total)',
                'tgs_proofread' => 'SUM(tgs_proofread)'
            ] )
            ->groupBy( 'tgs_lang' )
            ->caller( __METHOD__ )
            ->fetchResultSet();
 
        $allLanguages = self::getLanguages();
        $languagesCodes = array_flip( $allLanguages );
 
        $allStats = [];
        foreach ( $res as $row ) {
            $allStats[ $row->tgs_lang ] = self::extractNumbers( $row );
            unset( $languagesCodes[ $row->tgs_lang ] );
        }
 
        // Fill empty stats for missing language codes
        foreach ( array_keys( $languagesCodes ) as $code ) {
            $allStats[ $code ] = self::getEmptyStats();
        }
 
        return $allStats;
    }
 
    private static function internalClearGroups( string $code, array $groups, int $flags ): void {
        $stats = [];
        foreach ( $groups as $group ) {
            // $stats is modified by reference
            self::forItemInternal( $stats, $group, $code, $flags );
        }
        self::queueUpdates( 0 );
    }
 
    private static function getSortedGroupsForClearing( array $ids ): array {
        $groups = array_map( [ MessageGroups::class, 'getGroup' ], $ids );
        // Sanity: Remove any invalid groups
        $groups = array_filter( $groups );
 
        $sorted = [];
        $aggregates = [];
        foreach ( $groups as $group ) {
            if ( $group instanceof AggregateMessageGroup ) {
                $aggregates[$group->getId()] = $group;
            } else {
                $sorted[$group->getId()] = $group;
            }
        }
 
        return array_merge( $sorted, $aggregates );
    }
 
    public static function getLanguages(): array {
        if ( self::$languages === null ) {
            $languages = array_keys( Utilities::getLanguageNames( 'en' ) );
            sort( $languages );
            self::$languages = $languages;
        }
 
        return self::$languages;
    }
 
    private static function extractResults( iterable $res, array $ids, array $stats = [] ): array {
        // Map the internal ids back to real ids
        $idMap = array_combine( array_map( [ self::class, 'getDatabaseIdForGroupId' ], $ids ), $ids );
 
        foreach ( $res as $row ) {
            if ( !isset( $idMap[$row->tgs_group] ) ) {
                // Stale entry, ignore for now
                // TODO: Schedule for purge
                continue;
            }
 
            $realId = $idMap[$row->tgs_group];
            $stats[$realId][$row->tgs_lang] = self::extractNumbers( $row );
        }
 
        return $stats;
    }
 
    private static function extractNumbers( stdClass $row ): array {
        return [
            self::TOTAL => (int)$row->tgs_total,
            self::TRANSLATED => (int)$row->tgs_translated,
            self::FUZZY => (int)$row->tgs_fuzzy,
            self::PROOFREAD => (int)$row->tgs_proofread,
        ];
    }
 
    private static function forLanguageInternal( string $languageCode, array $stats, int $flags ): array {
        $groups = MessageGroups::singleton()->getGroups();
 
        $ids = array_keys( $groups );
        $res = self::selectRowsIdLang( null, [ $languageCode ], $flags );
        $stats = self::extractResults( $res, $ids, $stats );
 
        foreach ( $groups as $id => $group ) {
            if ( isset( $stats[$id][$languageCode] ) ) {
                continue;
            }
            $stats[$id][$languageCode] = self::forItemInternal( $stats, $group, $languageCode, $flags );
        }
 
        return $stats;
    }
 
    private static function expandAggregates( AggregateMessageGroup $agg ): array {
        $flattened = [];
 
        foreach ( $agg->getGroups() as $group ) {
            if ( $group instanceof AggregateMessageGroup ) {
                $flattened += self::expandAggregates( $group );
            } else {
                $flattened[$group->getId()] = $group;
            }
        }
 
        return $flattened;
    }
 
    private static function forGroupInternal( MessageGroup $group, array $stats, int $flags ): array {
        $id = $group->getId();
 
        $res = self::selectRowsIdLang( [ $id ], null, $flags );
        $stats = self::extractResults( $res, [ $id ], $stats );
 
        // Go over each language filling missing entries
        $languages = self::getLanguages();
        foreach ( $languages as $code ) {
            if ( isset( $stats[$id][$code] ) ) {
                continue;
            }
            $stats[$id][$code] = self::forItemInternal( $stats, $group, $code, $flags );
        }
 
        // This is for sorting the values added later in correct order
        foreach ( array_keys( $stats ) as $key ) {
            ksort( $stats[$key] );
        }
 
        return $stats;
    }
 
    private static function selectRowsIdLang( ?array $ids, ?array $codes, int $flags ): iterable {
        if ( $flags & self::FLAG_NO_CACHE ) {
            return [];
        }
 
        $conditions = [];
        if ( $ids !== null ) {
            $dbids = array_map( [ self::class, 'getDatabaseIdForGroupId' ], $ids );
            $conditions['tgs_group'] = $dbids;
        }
 
        if ( $codes !== null ) {
            $conditions['tgs_lang'] = $codes;
        }
 
        $dbr = Utilities::getSafeReadDB();
        return $dbr->newSelectQueryBuilder()
            ->select( '*' )
            ->from( self::TABLE )
            ->where( $conditions )
            ->caller( __METHOD__ )
            ->fetchResultSet();
    }
 
    private static function forItemInternal(
        array &$stats,
        MessageGroup $group,
        string $languageCode,
        int $flags
    ): array {
        $id = $group->getId();
 
        if ( $flags & self::FLAG_CACHE_ONLY ) {
            $stats[$id][$languageCode] = self::getUnknownStats();
            return $stats[$id][$languageCode];
        }
 
        // It may happen that caches are requested repeatedly for a group before we get a chance
        // to write the values to the database. Check for queued updates first. This has the
        // benefit of avoiding duplicate rows for inserts. Ideally this would be checked before we
        // query the database for missing values. This code is somewhat ugly as it needs to
        // reverse engineer the values from the row format.
        $databaseGroupId = self::getDatabaseIdForGroupId( $id );
        $uniqueKey = "$databaseGroupId|$languageCode";
        $queuedValue = self::$updates[$uniqueKey] ?? null;
        if ( $queuedValue && !( $flags & self::FLAG_NO_CACHE ) ) {
            return [
                self::TOTAL => $queuedValue['tgs_total'],
                self::TRANSLATED => $queuedValue['tgs_translated'],
                self::FUZZY => $queuedValue['tgs_fuzzy'],
                self::PROOFREAD => $queuedValue['tgs_proofread'],
            ];
        }
 
        if ( $group instanceof AggregateMessageGroup ) {
            $aggregates = self::calculateAggregateGroup( $stats, $group, $languageCode, $flags );
        } else {
            $aggregates = self::calculateGroup( $group, $languageCode );
        }
        // Cache for use in subsequent forItemInternal calls
        $stats[$id][$languageCode] = $aggregates;
 
        // Don't add nulls to the database, causes annoying warnings
        if ( $aggregates[self::TOTAL] === null ) {
            return $aggregates;
        }
 
        self::$updates[$uniqueKey] = [
            'tgs_group' => $databaseGroupId,
            'tgs_lang' => $languageCode,
            'tgs_total' => $aggregates[self::TOTAL],
            'tgs_translated' => $aggregates[self::TRANSLATED],
            'tgs_fuzzy' => $aggregates[self::FUZZY],
            'tgs_proofread' => $aggregates[self::PROOFREAD],
        ];
 
        // For big and lengthy updates, attempt some interim saves. This might not have
        // any effect, because writes to the database may be deferred.
        if ( count( self::$updates ) % 100 === 0 ) {
            self::queueUpdates( $flags );
        }
 
        return $aggregates;
    }
 
    private static function calculateAggregateGroup(
        array &$stats,
        AggregateMessageGroup $group,
        string $code,
        int $flags
    ): array {
        $aggregates = self::getEmptyStats();
 
        $expanded = self::expandAggregates( $group );
        $subGroupIds = array_keys( $expanded );
 
        // Performance: if we have per-call cache of stats, do not query them again.
        foreach ( $subGroupIds as $index => $sid ) {
            if ( isset( $stats[$sid][$code] ) ) {
                unset( $subGroupIds[ $index ] );
            }
        }
 
        if ( $subGroupIds !== [] ) {
            $res = self::selectRowsIdLang( $subGroupIds, [ $code ], $flags );
            $stats = self::extractResults( $res, $subGroupIds, $stats );
        }
 
        $messageGroupMetadata = Services::getInstance()->getMessageGroupMetadata();
        foreach ( $expanded as $sid => $subgroup ) {
            // Discouraged groups may belong to another group, usually if there
            // is an aggregate group for all translatable pages. In that case
            // calculate and store the statistics, but don't count them as part of
            // the aggregate group, so that the numbers in Special:LanguageStats
            // add up. The statistics for discouraged groups can still be viewed
            // through Special:MessageGroupStats.
            if ( !isset( $stats[$sid][$code] ) ) {
                $stats[$sid][$code] = self::forItemInternal( $stats, $subgroup, $code, $flags );
            }
 
            if ( !$messageGroupMetadata->isExcluded( $sid, $code ) ) {
                $aggregates = self::multiAdd( $aggregates, $stats[$sid][$code] );
            }
        }
 
        return $aggregates;
    }
 
    public static function multiAdd( array $a, array $b ): array {
        if ( $a[0] === null || $b[0] === null ) {
            return array_fill( 0, count( $a ), null );
        }
        foreach ( $a as $i => &$v ) {
            $v += $b[$i];
        }
 
        return $a;
    }
 
    private static function calculateGroup( MessageGroup $group, string $languageCode ): array {
        global $wgTranslateDocumentationLanguageCode;
        // Calculate if missing and store in the db
        $collection = $group->initCollection( $languageCode );
 
        if (
            $languageCode === $wgTranslateDocumentationLanguageCode
            && $group instanceof FileBasedMessageGroup
        ) {
            $cache = $group->getMessageGroupCache( $group->getSourceLanguage() );
            if ( $cache->exists() ) {
                $template = $cache->getExtra()['TEMPLATE'] ?? [];
                $infile = [];
                foreach ( $template as $key => $data ) {
                    if ( isset( $data['comments']['.'] ) ) {
                        $infile[$key] = '1';
                    }
                }
                $collection->setInFile( $infile );
            }
        }
 
        return self::getStatsForCollection( $collection );
    }
 
    private static function queueUpdates( int $flags ): void {
        $mwInstance = MediaWikiServices::getInstance();
        if ( self::$updates === [] || $mwInstance->getReadOnlyMode()->isReadOnly() ) {
            return;
        }
 
        $lb = $mwInstance->getDBLoadBalancer();
        $dbw = $lb->getConnection( DB_PRIMARY ); // avoid connecting yet
        $callers = wfGetAllCallers( 50 );
        $functionName = __METHOD__;
        $callback = static function ( IDatabase $dbw, $method ) use ( $callers, $mwInstance ) {
            // Maybe another deferred update already processed these
            if ( self::$updates === [] ) {
                return;
            }
 
            // This path should only be hit during web requests
            if ( count( self::$updates ) > 100 ) {
                $groups = array_unique( array_column( self::$updates, 'tgs_group' ) );
                LoggerFactory::getInstance( 'Translate' )->warning(
                    "Huge translation update of {count} rows for group(s) {groups}",
                    [
                        'count' => count( self::$updates ),
                        'groups' => implode( ', ', $groups ),
                        'callers' => $callers,
                    ]
                );
            }
 
            $primaryKey = [ 'tgs_group', 'tgs_lang' ];
            $dbw->replace( self::TABLE, [ $primaryKey ], array_values( self::$updates ), $method );
            self::$updates = [];
 
            $mwInstance->getMainWANObjectCache()->touchCheckKey( self::LANGUAGE_STATS_KEY );
        };
        $updateOp = static function () use ( $dbw, $functionName, $callback ) {
            $lockName = 'MessageGroupStats:updates';
            if ( !$dbw->lock( $lockName, $functionName, 1 ) ) {
                return; // raced out
            }
 
            $dbw->commit( $functionName, 'flush' );
            call_user_func( $callback, $dbw, $functionName );
            $dbw->commit( $functionName, 'flush' );
 
            $dbw->unlock( $lockName, $functionName );
        };
 
        if ( $flags & self::FLAG_IMMEDIATE_WRITES ) {
            call_user_func( $updateOp );
        } else {
            DeferredUpdates::addCallableUpdate( $updateOp );
        }
    }
 
    public static function getDatabaseIdForGroupId( string $id ): string {
        // The column is 100 bytes long, but we don't need to use it all
        if ( strlen( $id ) <= 72 ) {
            return $id;
        }
 
        $hash = hash( 'sha256', $id, /*asHex*/false );
        return substr( $id, 0, 50 ) . '||' . substr( $hash, 0, 20 );
    }
 
    public static function getStatsForCollection( MessageCollection $collection ): array {
        $collection->filter( 'ignored' );
        $collection->filterUntranslatedOptional();
        // Store the count of real messages for later calculation.
        $total = count( $collection );
 
        // Count fuzzy first.
        $collection->filter( 'fuzzy' );
        $fuzzy = $total - count( $collection );
 
        // Count the completed translations.
        $collection->filter( 'hastranslation', false );
        $translated = count( $collection );
 
        // Count how many of the completed translations
        // have been proofread
        $collection->filter( 'reviewer', false );
        $proofread = count( $collection );
 
        return [
            self::TOTAL => $total,
            self::TRANSLATED => $translated,
            self::FUZZY => $fuzzy,
            self::PROOFREAD => $proofread,
        ];
    }
}