wikimedia/mediawiki-extensions-Translate

<?php
declare( strict_types = 1 );

namespace MediaWiki\Extension\Translate\Synchronization;

use Cdb\Reader;
use Cdb\Writer;
use InvalidArgumentException;
use MediaWiki\Extension\Translate\MessageSync\MessageSourceChange;
use MediaWiki\Extension\Translate\Utilities\Utilities;

/**
 * Handles storage / retrieval of data from message change files.
 * @author Niklas Laxström
 * @license GPL-2.0-or-later
 */
class MessageChangeStorage {
    public const DEFAULT_NAME = 'default';

    /**
     * Writes change array as a serialized file.
     * @param MessageSourceChange[] $changes Array of changes as returned by processGroup
     * indexed by message group id.
     * @param string $file Which file to use.
     */
    public static function writeChanges( array $changes, string $file ): void {
        $cache = Writer::open( $file );
        $keys = array_keys( $changes );
        $cache->set( '#keys', Utilities::serialize( $keys ) );

        foreach ( $changes as $key => $change ) {
            $value = Utilities::serialize( $change->getAllModifications() );
            $cache->set( $key, $value );
        }
        $cache->close();
    }

    /** Validate a file name. */
    public static function isValidCdbName( string $fileName ): bool {
        return (bool)preg_match( '/^[a-z_-]{1,100}$/i', $fileName );
    }

    /** Get a full path to file in a known location. */
    public static function getCdbPath( string $fileName ): string {
        return Utilities::cacheFile( "messagechanges.$fileName.cdb" );
    }

    public static function getGroupChanges( string $cdbPath, string $groupId ): MessageSourceChange {
        $reader = self::getCdbReader( $cdbPath );
        if ( $reader === null ) {
            return MessageSourceChange::loadModifications( [] );
        }

        $groups = Utilities::deserialize( $reader->get( '#keys' ) );

        if ( !in_array( $groupId, $groups, true ) ) {
            throw new InvalidArgumentException( "Group Id - '$groupId' not found in cdb file " .
                "(path: $cdbPath)." );
        }

        return MessageSourceChange::loadModifications(
            Utilities::deserialize( $reader->get( $groupId ) )
        );
    }

    /**
     * Writes changes for a group. Has to read the changes first from the file
     * and then re-write them to the file.
     */
    public static function writeGroupChanges(
        MessageSourceChange $changes,
        string $groupId,
        string $cdbPath
    ): void {
        $reader = self::getCdbReader( $cdbPath );
        if ( $reader === null ) {
            return;
        }

        $groups = Utilities::deserialize( $reader->get( '#keys' ) );

        $allChanges = [];
        foreach ( $groups as $id ) {
            $allChanges[$id] = MessageSourceChange::loadModifications(
                Utilities::deserialize( $reader->get( $id ) )
            );
        }
        $allChanges[$groupId] = $changes;

        self::writeChanges( $allChanges, $cdbPath );
    }

    /** Validate and return a reader reference to the CDB file */
    private static function getCdbReader( string $cdbPath ): ?Reader {
        // File not found, probably no changes.
        if ( !file_exists( $cdbPath ) ) {
            return null;
        }

        return Reader::open( $cdbPath );
    }

    /**
     * Gets the last modified time for the CDB file.
     * @return int|null time of last modification (Unix timestamp)
     */
    public static function getLastModifiedTime( string $cdbPath ): ?int {
        // File not found
        if ( !file_exists( $cdbPath ) ) {
            return null;
        }

        $stat = stat( $cdbPath );

        return $stat['mtime'];
    }

    /** Checks if the CDB file has been modified since the time given. */
    public static function isModifiedSince( string $cdbPath, int $unixTimestamp ): bool {
        $lastModifiedTime = self::getLastModifiedTime( $cdbPath );

        if ( $lastModifiedTime === null ) {
            throw new InvalidArgumentException( "CDB file not found - $cdbPath" );
        }

        return $lastModifiedTime <= $unixTimestamp;
    }
}