class SvnDownloader

class SvnDownloader extends VcsDownloader {
    
    /** @var bool */
    protected $cacheCredentials = true;
    
    /**
     * @inheritDoc
     */
    protected function doDownload(PackageInterface $package, string $path, string $url, ?PackageInterface $prevPackage = null) : PromiseInterface {
        SvnUtil::cleanEnv();
        $util = new SvnUtil($url, $this->io, $this->config, $this->process);
        if (null === $util->binaryVersion()) {
            throw new \RuntimeException('svn was not found in your PATH, skipping source download');
        }
        return \React\Promise\resolve(null);
    }
    
    /**
     * @inheritDoc
     */
    protected function doInstall(PackageInterface $package, string $path, string $url) : PromiseInterface {
        SvnUtil::cleanEnv();
        $ref = $package->getSourceReference();
        $repo = $package->getRepository();
        if ($repo instanceof VcsRepository) {
            $repoConfig = $repo->getRepoConfig();
            if (array_key_exists('svn-cache-credentials', $repoConfig)) {
                $this->cacheCredentials = (bool) $repoConfig['svn-cache-credentials'];
            }
        }
        $this->io
            ->writeError(" Checking out " . $package->getSourceReference());
        $this->execute($package, $url, [
            'svn',
            'co',
        ], sprintf("%s/%s", $url, $ref), null, $path);
        return \React\Promise\resolve(null);
    }
    
    /**
     * @inheritDoc
     */
    protected function doUpdate(PackageInterface $initial, PackageInterface $target, string $path, string $url) : PromiseInterface {
        SvnUtil::cleanEnv();
        $ref = $target->getSourceReference();
        if (!$this->hasMetadataRepository($path)) {
            throw new \RuntimeException('The .svn directory is missing from ' . $path . ', see https://getcomposer.org/commit-deps for more information');
        }
        $util = new SvnUtil($url, $this->io, $this->config, $this->process);
        $flags = [];
        if (version_compare($util->binaryVersion(), '1.7.0', '>=')) {
            $flags[] = '--ignore-ancestry';
        }
        $this->io
            ->writeError(" Checking out " . $ref);
        $this->execute($target, $url, array_merge([
            'svn',
            'switch',
        ], $flags), sprintf("%s/%s", $url, $ref), $path);
        return \React\Promise\resolve(null);
    }
    
    /**
     * @inheritDoc
     */
    public function getLocalChanges(PackageInterface $package, string $path) : ?string {
        if (!$this->hasMetadataRepository($path)) {
            return null;
        }
        $this->process
            ->execute([
            'svn',
            'status',
            '--ignore-externals',
        ], $output, $path);
        return Preg::isMatch('{^ *[^X ] +}m', $output) ? $output : null;
    }
    
    /**
     * Execute an SVN command and try to fix up the process with credentials
     * if necessary.
     *
     * @param  string            $baseUrl Base URL of the repository
     * @param  non-empty-list<string> $command SVN command to run
     * @param  string            $url     SVN url
     * @param  string            $cwd     Working directory
     * @param  string            $path    Target for a checkout
     * @throws \RuntimeException
     */
    protected function execute(PackageInterface $package, string $baseUrl, array $command, string $url, ?string $cwd = null, ?string $path = null) : string {
        $util = new SvnUtil($baseUrl, $this->io, $this->config, $this->process);
        $util->setCacheCredentials($this->cacheCredentials);
        try {
            return $util->execute($command, $url, $cwd, $path, $this->io
                ->isVerbose());
        } catch (\RuntimeException $e) {
            throw new \RuntimeException($package->getPrettyName() . ' could not be downloaded, ' . $e->getMessage());
        }
    }
    
    /**
     * @inheritDoc
     */
    protected function cleanChanges(PackageInterface $package, string $path, bool $update) : PromiseInterface {
        if (null === ($changes = $this->getLocalChanges($package, $path))) {
            return \React\Promise\resolve(null);
        }
        if (!$this->io
            ->isInteractive()) {
            if (true === $this->config
                ->get('discard-changes')) {
                return $this->discardChanges($path);
            }
            return parent::cleanChanges($package, $path, $update);
        }
        $changes = array_map(static function ($elem) : string {
            return '    ' . $elem;
        }, Preg::split('{\\s*\\r?\\n\\s*}', $changes));
        $countChanges = count($changes);
        $this->io
            ->writeError(sprintf('    <error>' . $package->getPrettyName() . ' has modified file%s:</error>', $countChanges === 1 ? '' : 's'));
        $this->io
            ->writeError(array_slice($changes, 0, 10));
        if ($countChanges > 10) {
            $remainingChanges = $countChanges - 10;
            $this->io
                ->writeError(sprintf('    <info>' . $remainingChanges . ' more file%s modified, choose "v" to view the full list</info>', $remainingChanges === 1 ? '' : 's'));
        }
        while (true) {
            switch ($this->io
                ->ask('    <info>Discard changes [y,n,v,?]?</info> ', '?')) {
                case 'y':
                    $this->discardChanges($path);
                    break 2;
                case 'n':
                    throw new \RuntimeException('Update aborted');
                case 'v':
                    $this->io
                        ->writeError($changes);
                    break;
                case '?':
                default:
                    $this->io
                        ->writeError([
                        '    y - discard changes and apply the ' . ($update ? 'update' : 'uninstall'),
                        '    n - abort the ' . ($update ? 'update' : 'uninstall') . ' and let you manually clean things up',
                        '    v - view modified files',
                        '    ? - print help',
                    ]);
                    break;
            }
        }
        return \React\Promise\resolve(null);
    }
    
    /**
     * @inheritDoc
     */
    protected function getCommitLogs(string $fromReference, string $toReference, string $path) : string {
        if (Preg::isMatch('{@(\\d+)$}', $fromReference) && Preg::isMatch('{@(\\d+)$}', $toReference)) {
            // retrieve the svn base url from the checkout folder
            $command = [
                'svn',
                'info',
                '--non-interactive',
                '--xml',
                '--',
                $path,
            ];
            if (0 !== $this->process
                ->execute($command, $output, $path)) {
                throw new \RuntimeException('Failed to execute ' . implode(' ', $command) . "\n\n" . $this->process
                    ->getErrorOutput());
            }
            $urlPattern = '#<url>(.*)</url>#';
            if (Preg::isMatchStrictGroups($urlPattern, $output, $matches)) {
                $baseUrl = $matches[1];
            }
            else {
                throw new \RuntimeException('Unable to determine svn url for path ' . $path);
            }
            // strip paths from references and only keep the actual revision
            $fromRevision = Preg::replace('{.*@(\\d+)$}', '$1', $fromReference);
            $toRevision = Preg::replace('{.*@(\\d+)$}', '$1', $toReference);
            $command = [
                'svn',
                'log',
                '-r',
                $fromRevision . ':' . $toRevision,
                '--incremental',
            ];
            $util = new SvnUtil($baseUrl, $this->io, $this->config, $this->process);
            $util->setCacheCredentials($this->cacheCredentials);
            try {
                return $util->executeLocal($command, $path, null, $this->io
                    ->isVerbose());
            } catch (\RuntimeException $e) {
                throw new \RuntimeException('Failed to execute ' . implode(' ', $command) . "\n\n" . $e->getMessage());
            }
        }
        return "Could not retrieve changes between {$fromReference} and {$toReference} due to missing revision information";
    }
    
    /**
     * @phpstan-return PromiseInterface<void|null>
     */
    protected function discardChanges(string $path) : PromiseInterface {
        if (0 !== $this->process
            ->execute([
            'svn',
            'revert',
            '-R',
            '.',
        ], $output, $path)) {
            throw new \RuntimeException("Could not reset changes\n\n:" . $this->process
                ->getErrorOutput());
        }
        return \React\Promise\resolve(null);
    }
    
    /**
     * @inheritDoc
     */
    protected function hasMetadataRepository(string $path) : bool {
        return is_dir($path . '/.svn');
    }

}