SafeWriter.h

#pragma once

#include <string>
#include <utility>

#include <Poco/CountingStream.h>
#include <Poco/DigestStream.h>
#include <Poco/File.h>
#include <Poco/FileStream.h>
#include <Poco/Path.h>
#include <Poco/SHA1Engine.h>
#include <Poco/TemporaryFile.h>

#include "util/Loggable.h"

namespace BeeeOn {

class SafeWriter : Loggable {
public:
        SafeWriter(const Poco::File &tmpFile);
        SafeWriter(const Poco::File &tmpFile, const std::string &ext);
        ~SafeWriter();

        std::ostream &stream(bool force = false);

        void flush();

        void reset();

        std::pair<Poco::DigestEngine::Digest, size_t> finalize();

        void commitAs(const Poco::File &targetFile);

protected:
        void createLockFile(bool force);

private:
        Poco::File m_tmpFile;
        Poco::FileOutputStream m_fileStream;
        Poco::SHA1Engine m_engine;
        Poco::DigestOutputStream m_digestStream;
        Poco::DigestEngine::Digest m_recentDigest;
        Poco::CountingOutputStream m_countingStream;
        size_t m_recentLength;
        std::ostream &m_stream;
        bool m_created;
        bool m_finalized;
        bool m_committed;
};

}