/**
  * Execute rollback and upgrade one version.
  *
  * @param \Jumilla\Versionia\Laravel\Migrator $migrator
  * @param string                              $group
  */
 protected function doAgain(Migrator $migrator, $group)
 {
     // retreive installed versions
     $installed_migrations = $migrator->installedLatestMigrations();
     $installed_version = data_get($installed_migrations, $group . '.version', Migrator::VERSION_NULL);
     $definition_versions = $migrator->migrationVersionsByDesc($group);
     if (!$this->checkInstalledVersion($installed_version, $definition_versions)) {
         return;
     }
     // remove migration log
     $definition_latest_version = array_get(array_keys($definition_versions), 0, Migrator::VERSION_NULL);
     if ($migrator->compareMigrationVersion($installed_version, $definition_latest_version) >= 0) {
         $this->line("<info>Remove log [{$group}/{$installed_version}]</info>");
         $migrator->removeMigrationLog($group, $installed_version);
     }
     // downgrade & upgrade
     foreach ($definition_versions as $version => $class) {
         $this->infoDowngrade($group, $version, $class);
         $migrator->doDowngrade($group, $version, $class);
         $this->infoUpgrade($group, $version, $class);
         $migrator->doUpgrade($group, $version, $class);
         break;
     }
 }