/**
* convert via openOffice hosted on the same server
* @param string $input
* @param string $targetFilter
* @param string $targetExtension
* @return string
*/
protected static function convertLocal($input, $targetFilter, $targetExtension)
{
$infile = \OC::$server->getTempManager()->getTemporaryFile();
$outdir = \OC::$server->getTempManager()->getTemporaryFolder();
$cmd = Helper::findOpenOffice();
$params = ' --headless --convert-to ' . $targetFilter . ' --outdir ' . escapeshellarg($outdir) . ' --writer ' . escapeshellarg($infile) . ' -env:UserInstallation=file://' . escapeshellarg(\OC::$server->getTempManager()->getTempBaseDir() . '/owncloud-' . \OC_Util::getInstanceId() . '/');
file_put_contents($infile, $input);
shell_exec($cmd . $params);
$output = file_get_contents($outdir . '/' . basename($infile) . '.' . $targetExtension);
return $output;
}