/*******************************************************************************
 * Copyright (c) 2026, Jan Koester jan.koester@gmx.net
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 * Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 * Neither the name of the <organization> nor the
 *      names of its contributors may be used to endorse or promote products
 *      derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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 *******************************************************************************/

#pragma once

#include <vector>
#include <cstdint>
#include <atomic>
#include <chrono>

#include "../backend.h"
#include "../authdb.h"

#ifdef Windows
#define VISIBILITY __declspec(dllexport)
#else
#define VISIBILITY __attribute__((visibility("default")))
#endif

namespace authdb {
    class VISIBILITY ClusterBackend : public AuthBackendApi {
    public:
        ClusterBackend(const char *domain, size_t version, const char *filepath = nullptr);
        virtual ~ClusterBackend();

        void write(const unsigned char *dest, size_t destsize);
        void read(unsigned char *src, size_t srcsize);

        void lock();
        void unlock();

        void setPos(size_t pos);
        size_t getPos();

        size_t end();

        size_t getRevesion();
        void newRevesion();

        void vacuum();
        void purge();

        bool clusterDataExists() const override { return _ClusterDataExists.load(); }

    private:
        uint64_t domainGroupId() const;
        void fetchFromCluster();
        void pushToCluster();
        bool pushToClusterAsync(uint64_t dgid, const std::vector<uint8_t> &buf);

        std::string              _Domain;
        std::vector<uint8_t>     _Buffer;
        size_t                   _Pos;
        std::atomic<bool>        _Dirty;
        std::atomic<bool>        _ClusterDataExists{false};
        std::chrono::steady_clock::time_point _LastPeerFetch{};
    };
};
