oxen-core/src/cryptonote_core/service_node_quorum_cop.h

// Copyright (c)      2018, The Loki Project
//
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#pragma once

#include "blockchain.h"
#include "cryptonote_protocol/cryptonote_protocol_handler_common.h"

namespace cryptonote
{
  class core;
};

namespace service_nodes
{
  class quorum_cop
    : public cryptonote::Blockchain::BlockAddedHook,
      public cryptonote::Blockchain::BlockchainDetachedHook,
      public cryptonote::Blockchain::InitHook
  {
  public:
    explicit quorum_cop(cryptonote::core& core);

    void init() override;
    void block_added(const cryptonote::block& block, const std::vector<cryptonote::transaction>& txs) override;
    void blockchain_detached(uint64_t height) override;

    bool handle_uptime_proof(const cryptonote::NOTIFY_UPTIME_PROOF::request &proof);

    static const uint64_t REORG_SAFETY_BUFFER_IN_BLOCKS = 20;
    static_assert(REORG_SAFETY_BUFFER_IN_BLOCKS < deregister_vote::VOTE_LIFETIME_BY_HEIGHT,
                  "Safety buffer should always be less than the vote lifetime");
    bool prune_uptime_proof();

    uint64_t get_uptime_proof(const crypto::public_key &pubkey) const;

    void generate_uptime_proof_request(cryptonote::NOTIFY_UPTIME_PROOF::request& req) const;

  private:

    cryptonote::core& m_core;
    uint64_t m_last_height;

    using timestamp = uint64_t;
    std::unordered_map<crypto::public_key, timestamp> m_uptime_proof_seen;
    mutable epee::critical_section m_lock;
  };
}