// Copyright (c)      2018, The Loki Project
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
//    conditions and the following disclaimer.
//
// 2. 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.
//
// 3. Neither the name of the copyright holder 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 DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include <fmt/chrono.h>
#include <fmt/color.h>
#include <fmt/core.h>
#include <oxenc/endian.h>
#include <oxenc/hex.h>

#include <algorithm>
#include <chrono>
#include <functional>

#include "cryptonote_config.h"
#include "oxen_economy.h"
#include "ringct/rctTypes.h"

extern "C" {
#include <sodium.h>
}

#include "blockchain.h"
#include "common/hex.h"
#include "common/i18n.h"
#include "common/lock.h"
#include "common/random.h"
#include "common/scoped_message_writer.h"
#include "common/util.h"
#include "cryptonote_basic/hardfork.h"
#include "cryptonote_basic/tx_extra.h"
#include "cryptonote_core/uptime_proof.h"
#include "cryptonote_tx_utils.h"
#include "epee/int-util.h"
#include "epee/net/local_ip.h"
#include "pulse.h"
#include "ringct/rctSigs.h"
#include "service_node_list.h"
#include "service_node_quorum_cop.h"
#include "service_node_rules.h"
#include "service_node_swarm.h"
#include "uptime_proof.h"
#include "version.h"

using cryptonote::hf;

namespace service_nodes {
static auto logcat = log::Cat("service_nodes");

size_t constexpr STORE_LONG_TERM_STATE_INTERVAL = 10000;

constexpr auto X25519_MAP_PRUNING_INTERVAL = 5min;
constexpr auto X25519_MAP_PRUNING_LAG = 24h;
static_assert(
        X25519_MAP_PRUNING_LAG > cryptonote::config::UPTIME_PROOF_VALIDITY,
        "x25519 map pruning lag is too short!");

static uint64_t short_term_state_cull_height(hf hf_version, uint64_t block_height) {
    size_t constexpr DEFAULT_SHORT_TERM_STATE_HISTORY = 6 * STATE_CHANGE_TX_LIFETIME_IN_BLOCKS;
    static_assert(
            DEFAULT_SHORT_TERM_STATE_HISTORY >=
                    12 * cryptonote::BLOCKS_PER_HOUR,  // Arbitrary, but raises a compilation
                                                       // failure if it gets shortened.
            "not enough short term state storage for blink quorum retrieval!");
    uint64_t result = (block_height < DEFAULT_SHORT_TERM_STATE_HISTORY)
                            ? 0
                            : block_height - DEFAULT_SHORT_TERM_STATE_HISTORY;
    return result;
}

service_node_list::service_node_list(cryptonote::Blockchain& blockchain) :
        m_blockchain(
                blockchain)  // Warning: don't touch `blockchain`, it gets initialized *after* us
        ,
        m_service_node_keys(nullptr),
        m_state{this} {}

void service_node_list::init() {
    std::lock_guard lock(m_sn_mutex);
    if (m_blockchain.get_network_version() < hf::hf9_service_nodes) {
        reset(true);
        return;
    }

    uint64_t current_height = m_blockchain.get_current_blockchain_height();
    bool loaded = load(current_height);
    if (loaded &&
        m_transient.old_quorum_states.size() < std::min(m_store_quorum_history, uint64_t{10})) {
        log::warning(
                logcat,
                "Full history storage requested, but {} old quorum states found",
                m_transient.old_quorum_states.size());
        loaded = false;  // Either we don't have stored history or the history is very short, so
                         // recalculation is necessary or cheap.
    }

    if (!loaded || m_state.height > current_height)
        reset(true);
}

template <typename UnaryPredicate>
static std::vector<service_nodes::pubkey_and_sninfo> sort_and_filter(
        const service_nodes_infos_t& sns_infos, UnaryPredicate p, bool reserve = true) {
    std::vector<pubkey_and_sninfo> result;
    if (reserve)
        result.reserve(sns_infos.size());
    for (const auto& key_info : sns_infos)
        if (p(*key_info.second))
            result.push_back(key_info);

    std::sort(
            result.begin(),
            result.end(),
            [](const pubkey_and_sninfo& a, const pubkey_and_sninfo& b) {
                return memcmp(reinterpret_cast<const void*>(&a),
                              reinterpret_cast<const void*>(&b),
                              sizeof(a)) < 0;
            });
    return result;
}

std::vector<pubkey_and_sninfo> service_node_list::state_t::active_service_nodes_infos() const {
    return sort_and_filter(
            service_nodes_infos,
            [](const service_node_info& info) { return info.is_active(); },
            /*reserve=*/true);
}

std::vector<pubkey_and_sninfo> service_node_list::state_t::decommissioned_service_nodes_infos()
        const {
    return sort_and_filter(
            service_nodes_infos,
            [](const service_node_info& info) {
                return info.is_decommissioned() && info.is_fully_funded();
            },
            /*reserve=*/false);
}

std::vector<pubkey_and_sninfo> service_node_list::state_t::payable_service_nodes_infos(
        uint64_t height, cryptonote::network_type nettype) const {
    return sort_and_filter(
            service_nodes_infos,
            [height, nettype](const service_node_info& info) {
                return info.is_payable(height, nettype);
            },
            /*reserve=*/true);
}

std::shared_ptr<const quorum> service_node_list::get_quorum(
        quorum_type type,
        uint64_t height,
        bool include_old,
        std::vector<std::shared_ptr<const quorum>>* alt_quorums) const {
    height = offset_testing_quorum_height(type, height);
    std::lock_guard lock(m_sn_mutex);
    quorum_manager const* quorums = nullptr;
    if (height == m_state.height)
        quorums = &m_state.quorums;
    else  // NOTE: Search m_transient.state_history && m_transient.state_archive
    {
        auto it = m_transient.state_history.find(height);
        if (it != m_transient.state_history.end())
            quorums = &it->quorums;

        if (!quorums) {
            auto it = m_transient.state_archive.find(height);
            if (it != m_transient.state_archive.end())
                quorums = &it->quorums;
        }
    }

    if (!quorums && include_old)  // NOTE: Search m_transient.old_quorum_states
    {
        auto it = std::lower_bound(
                m_transient.old_quorum_states.begin(),
                m_transient.old_quorum_states.end(),
                height,
                [](quorums_by_height const& entry, uint64_t height) {
                    return entry.height < height;
                });

        if (it != m_transient.old_quorum_states.end() && it->height == height)
            quorums = &it->quorums;
    }

    if (alt_quorums) {
        for (const auto& [hash, alt_state] : m_transient.alt_state) {
            if (alt_state.height == height) {
                std::shared_ptr<const quorum> alt_result = alt_state.quorums.get(type);
                if (alt_result)
                    alt_quorums->push_back(alt_result);
            }
        }
    }

    if (!quorums)
        return nullptr;

    std::shared_ptr<const quorum> result = quorums->get(type);
    return result;
}

static bool get_pubkey_from_quorum(
        quorum const& quorum, quorum_group group, size_t quorum_index, crypto::public_key& key) {
    std::vector<crypto::public_key> const* array = nullptr;
    if (group == quorum_group::validator)
        array = &quorum.validators;
    else if (group == quorum_group::worker)
        array = &quorum.workers;
    else {
        log::error(logcat, "Invalid quorum group specified");
        return false;
    }

    if (quorum_index >= array->size()) {
        log::error(
                logcat,
                "Quorum indexing out of bounds: {}, quorum_size: {}",
                quorum_index,
                array->size());
        return false;
    }

    key = (*array)[quorum_index];
    return true;
}

bool service_node_list::get_quorum_pubkey(
        quorum_type type,
        quorum_group group,
        uint64_t height,
        size_t quorum_index,
        crypto::public_key& key) const {
    std::shared_ptr<const quorum> quorum = get_quorum(type, height);
    if (!quorum) {
        log::info(logcat, "Quorum for height: {}, was not stored by the daemon", height);
        return false;
    }

    bool result = get_pubkey_from_quorum(*quorum, group, quorum_index, key);
    return result;
}

size_t service_node_list::get_service_node_count() const {
    std::lock_guard lock(m_sn_mutex);
    return m_state.service_nodes_infos.size();
}

std::vector<service_node_pubkey_info> service_node_list::get_service_node_list_state(
        const std::vector<crypto::public_key>& service_node_pubkeys) const {
    std::lock_guard lock(m_sn_mutex);
    std::vector<service_node_pubkey_info> result;

    if (service_node_pubkeys.empty()) {
        result.reserve(m_state.service_nodes_infos.size());

        for (const auto& info : m_state.service_nodes_infos)
            result.emplace_back(info);
    } else {
        result.reserve(service_node_pubkeys.size());
        for (const auto& it : service_node_pubkeys) {
            auto find_it = m_state.service_nodes_infos.find(it);
            if (find_it != m_state.service_nodes_infos.end())
                result.emplace_back(*find_it);
        }
    }

    return result;
}

void service_node_list::set_my_service_node_keys(const service_node_keys* keys) {
    std::lock_guard lock(m_sn_mutex);
    m_service_node_keys = keys;
}

void service_node_list::set_quorum_history_storage(uint64_t hist_size) {
    if (hist_size == 1)
        hist_size = std::numeric_limits<uint64_t>::max();
    m_store_quorum_history = hist_size;
}

bool service_node_list::is_service_node(
        const crypto::public_key& pubkey, bool require_active) const {
    std::lock_guard lock(m_sn_mutex);
    auto it = m_state.service_nodes_infos.find(pubkey);
    return it != m_state.service_nodes_infos.end() && (!require_active || it->second->is_active());
}

bool service_node_list::is_key_image_locked(
        crypto::key_image const& check_image,
        uint64_t* unlock_height,
        service_node_info::contribution_t* the_locked_contribution) const {
    for (const auto& pubkey_info : m_state.service_nodes_infos) {
        const service_node_info& info = *pubkey_info.second;
        for (const service_node_info::contributor_t& contributor : info.contributors) {
            for (const service_node_info::contribution_t& contribution :
                 contributor.locked_contributions) {
                if (check_image == contribution.key_image) {
                    if (the_locked_contribution)
                        *the_locked_contribution = contribution;
                    if (unlock_height)
                        *unlock_height = info.requested_unlock_height;
                    return true;
                }
            }
        }
    }
    return false;
}

std::optional<registration_details> reg_tx_extract_fields(const cryptonote::transaction& tx) {
    cryptonote::tx_extra_service_node_register registration;
    if (!get_field_from_tx_extra(tx.extra, registration))
        return std::nullopt;

    if (registration.public_spend_keys.size() != registration.public_view_keys.size() ||
        registration.amounts.size() != registration.public_spend_keys.size())
        return std::nullopt;

    registration_details reg{};
    if (!cryptonote::get_service_node_pubkey_from_tx_extra(tx.extra, reg.service_node_pubkey))
        return std::nullopt;

    reg.reserved.reserve(registration.public_spend_keys.size());
    for (size_t i = 0; i < registration.public_spend_keys.size(); i++) {
        auto& [addr, amount] = reg.reserved.emplace_back();
        addr.m_spend_public_key = registration.public_spend_keys[i];
        addr.m_view_public_key = registration.public_view_keys[i];
        amount = registration.amounts[i];
    }

    reg.hf = registration.hf_or_expiration;
    if (registration.hf_or_expiration <= 255)
        reg.uses_portions = false;
    else
        // Unix timestamp, so pre-HF19 and uses portions
        reg.uses_portions = true;

    reg.fee = registration.fee;
    reg.signature = registration.signature;

    return reg;
}

uint64_t offset_testing_quorum_height(quorum_type type, uint64_t height) {
    uint64_t result = height;
    if (type == quorum_type::checkpointing) {
        if (result < REORG_SAFETY_BUFFER_BLOCKS_POST_HF12)
            return 0;
        result -= REORG_SAFETY_BUFFER_BLOCKS_POST_HF12;
    }
    return result;
}

void validate_registration(
        hf hf_version,
        cryptonote::network_type nettype,
        uint64_t staking_requirement,
        uint64_t block_timestamp,
        const registration_details& reg) {
    if (reg.uses_portions) {
        if (hf_version >= hf::hf19_reward_batching)
            throw invalid_registration{"Portion-based registrations are not permitted in HF19+"};
    } else {
        // If not using portions then the hf value must be >= 19 and equal to the current blockchain
        // hf:
        if (hf_version < hf::hf19_reward_batching || reg.hf != static_cast<uint8_t>(hf_version))
            throw invalid_registration{
                    "Wrong registration hardfork {}; you likely need to regenerate "
                    "the registration for compatibility with hardfork {}"_format(
                            reg.hf, static_cast<uint8_t>(hf_version))};
    }

    const size_t max_contributors = hf_version >= hf::hf19_reward_batching
                                          ? oxen::MAX_CONTRIBUTORS_HF19
                                          : oxen::MAX_CONTRIBUTORS_V1;

    if (reg.reserved.empty())
        throw invalid_registration{"No operator contribution given"};
    if (reg.reserved.size() > max_contributors)
        throw invalid_registration{"Too many contributors"};

    bool valid_stakes, valid_fee;
    if (reg.uses_portions) {
        // HF18 or earlier registration
        valid_stakes = check_service_node_portions(hf_version, reg.reserved);
        valid_fee = reg.fee <= cryptonote::old::STAKING_PORTIONS;
    } else {
        valid_stakes =
                check_service_node_stakes(hf_version, nettype, staking_requirement, reg.reserved);
        valid_fee = reg.fee <= cryptonote::STAKING_FEE_BASIS;
    }

    if (!valid_fee)
        throw invalid_registration{"Operator fee is too high ({} > {})"_format(
                reg.fee,
                reg.uses_portions ? cryptonote::old::STAKING_PORTIONS
                                  : cryptonote::STAKING_FEE_BASIS)};

    if (!valid_stakes) {
        std::string amount_dump;
        amount_dump.reserve(22 * reg.reserved.size());
        for (size_t i = 0; i < reg.reserved.size(); i++) {
            if (i)
                amount_dump += ", ";
            amount_dump += std::to_string(reg.reserved[i].second);
        }
        throw invalid_registration{
                "Invalid "s + (reg.uses_portions ? "portions" : "amounts") + ": {" + amount_dump +
                "}"};
    }

    // If using portions then `.hf` is actually the registration expiry (HF19+ registrations do not
    // expire).
    if (reg.uses_portions && reg.hf < block_timestamp)
        throw invalid_registration{
                "Registration expired (" + std::to_string(reg.hf) + " < " +
                std::to_string(block_timestamp) + ")"};
}

//---------------------------------------------------------------
crypto::hash get_registration_hash(const registration_details& registration) {
    std::string buffer;
    size_t size = sizeof(uint64_t) +  // fee
                  registration.reserved.size() * (sizeof(cryptonote::account_public_address) +
                                                  sizeof(uint64_t)) +  // addr+amount for each
                  sizeof(uint64_t);                                    // expiration timestamp
    buffer.reserve(size);
    buffer += tools::view_guts(oxenc::host_to_little(registration.fee));
    for (const auto& [addr, amount] : registration.reserved) {
        buffer += tools::view_guts(addr);
        buffer += tools::view_guts(oxenc::host_to_little(amount));
    }
    buffer += tools::view_guts(oxenc::host_to_little(registration.hf));
    assert(buffer.size() == size);
    return crypto::cn_fast_hash(buffer.data(), buffer.size());
}

void validate_registration_signature(const registration_details& registration) {
    auto hash = get_registration_hash(registration);
    if (!crypto::check_key(registration.service_node_pubkey))
        throw invalid_registration{
                "Service Node Key is not a valid public key (" +
                tools::type_to_hex(registration.service_node_pubkey) + ")"};

    if (!crypto::check_signature(hash, registration.service_node_pubkey, registration.signature))
        throw invalid_registration{
                "Registration signature verification failed for pubkey/hash: " +
                tools::type_to_hex(registration.service_node_pubkey) + "/" +
                tools::type_to_hex(hash)};
}

struct parsed_tx_contribution {
    cryptonote::account_public_address address;
    uint64_t transferred;
    crypto::secret_key tx_key;
    std::vector<service_node_info::contribution_t> locked_contributions;
};

static uint64_t get_staking_output_contribution(
        const cryptonote::transaction& tx,
        int i,
        crypto::key_derivation const& derivation,
        hw::device& hwdev) {
    if (!std::holds_alternative<cryptonote::txout_to_key>(tx.vout[i].target)) {
        return 0;
    }

    rct::key mask;
    uint64_t money_transferred = 0;

    crypto::secret_key scalar1;
    hwdev.derivation_to_scalar(derivation, i, scalar1);
    try {
        switch (tx.rct_signatures.type) {
            case rct::RCTType::Simple:
            case rct::RCTType::Bulletproof:
            case rct::RCTType::Bulletproof2:
            case rct::RCTType::CLSAG:
                money_transferred = rct::decodeRctSimple(
                        tx.rct_signatures, rct::sk2rct(scalar1), i, mask, hwdev);
                break;
            case rct::RCTType::Full:
                money_transferred =
                        rct::decodeRct(tx.rct_signatures, rct::sk2rct(scalar1), i, mask, hwdev);
                break;
            default:
                log::warning(
                        logcat,
                        "{}: Unsupported rct type: {}",
                        __func__,
                        (int)tx.rct_signatures.type);
                return 0;
        }
    } catch (const std::exception& e) {
        log::warning(logcat, "Failed to decode input {}", i);
        return 0;
    }

    return money_transferred;
}

bool tx_get_staking_components(
        cryptonote::transaction_prefix const& tx,
        staking_components* contribution,
        crypto::hash const& txid) {
    staking_components contribution_unused_ = {};
    if (!contribution)
        contribution = &contribution_unused_;
    if (!cryptonote::get_service_node_pubkey_from_tx_extra(
                tx.extra, contribution->service_node_pubkey))
        return false;  // Is not a contribution TX don't need to check it.

    if (!cryptonote::get_service_node_contributor_from_tx_extra(tx.extra, contribution->address))
        return false;

    if (!cryptonote::get_tx_secret_key_from_tx_extra(tx.extra, contribution->tx_key)) {
        log::info(
                logcat,
                "TX: There was a service node contributor but no secret key in the tx extra for "
                "tx: {}",
                txid);
        return false;
    }

    return true;
}

bool tx_get_staking_components(
        cryptonote::transaction const& tx, staking_components* contribution) {
    bool result = tx_get_staking_components(tx, contribution, cryptonote::get_transaction_hash(tx));
    return result;
}

bool tx_get_staking_components_and_amounts(
        cryptonote::network_type nettype,
        hf hf_version,
        cryptonote::transaction const& tx,
        uint64_t block_height,
        staking_components* contribution) {
    staking_components contribution_unused_ = {};
    if (!contribution)
        contribution = &contribution_unused_;

    if (!tx_get_staking_components(tx, contribution))
        return false;

    // A cryptonote transaction is constructed as follows
    // P = Hs(aR)G + B

    // P := Stealth Address
    // a := Receiver's secret view key
    // B := Receiver's public spend key
    // R := TX Public Key
    // G := Elliptic Curve

    // In Loki we pack into the tx extra information to reveal information about the TX
    // A := Public View Key (we pack contributor into tx extra, 'parsed_contribution.address')
    // r := TX Secret Key   (we pack secret key into tx extra,  'parsed_contribution.tx_key`)

    // Calulate 'Derivation := Hs(Ar)G'
    crypto::key_derivation derivation;
    if (!crypto::generate_key_derivation(
                contribution->address.m_view_public_key, contribution->tx_key, derivation)) {
        log::info(
                logcat,
                "TX: Failed to generate key derivation on height: {} for tx: {}",
                block_height,
                cryptonote::get_transaction_hash(tx));
        return false;
    }

    hw::device& hwdev = hw::get_device("default");
    contribution->transferred = 0;
    bool stake_decoded = true;
    if (hf_version >= hf::hf11_infinite_staking) {
        // In Infinite Staking, we lock the key image that would be generated if
        // you tried to send your stake and prevent it from being transacted on
        // the network whilst you are a Service Node. To do this, we calculate
        // the future key image that would be generated when they user tries to
        // spend the staked funds. A key image is derived from the ephemeral, one
        // time transaction private key, 'x' in the Cryptonote Whitepaper.

        // This is only possible to generate if they are the staking to themselves
        // as you need the recipients private keys to generate the key image that
        // would be generated, when they want to spend it in the future.

        cryptonote::tx_extra_tx_key_image_proofs key_image_proofs;
        if (!get_field_from_tx_extra(tx.extra, key_image_proofs)) {
            log::info(
                    logcat,
                    "TX: Didn't have key image proofs in the tx_extra, rejected on height: {} for "
                    "tx: {}",
                    block_height,
                    cryptonote::get_transaction_hash(tx));
            stake_decoded = false;
        }

        for (size_t output_index = 0; stake_decoded && output_index < tx.vout.size();
             ++output_index) {
            uint64_t transferred =
                    get_staking_output_contribution(tx, output_index, derivation, hwdev);
            if (transferred == 0)
                continue;

            // So prove that the destination stealth address can be decoded using the
            // staker's packed address, which means that the recipient of the
            // contribution is themselves (and hence they have the necessary secrets
            // to generate the future key image).

            // i.e Verify the packed information is valid by computing the stealth
            // address P' (which should equal P if matching) using

            // 'Derivation := Hs(Ar)G' (we calculated earlier) instead of 'Hs(aR)G'
            // P' = Hs(Ar)G + B
            //    = Hs(aR)G + B
            //    = Derivation + B
            //    = P

            crypto::public_key ephemeral_pub_key;
            {
                // P' := Derivation + B
                if (!hwdev.derive_public_key(
                            derivation,
                            output_index,
                            contribution->address.m_spend_public_key,
                            ephemeral_pub_key)) {
                    log::info(
                            logcat,
                            "TX: Could not derive TX ephemeral key on height: {} for tx: {} for "
                            "output: {}",
                            block_height,
                            get_transaction_hash(tx),
                            output_index);
                    continue;
                }

                // Stealth address public key should match the public key referenced in the TX only
                // if valid information is given.
                const auto& out_to_key =
                        var::get<cryptonote::txout_to_key>(tx.vout[output_index].target);
                if (out_to_key.key != ephemeral_pub_key) {
                    log::info(
                            logcat,
                            "TX: Derived TX ephemeral key did not match tx stored key on height: "
                            "{} for tx: {} for output: {}",
                            block_height,
                            cryptonote::get_transaction_hash(tx),
                            output_index);
                    continue;
                }
            }

            // To prevent the staker locking any arbitrary key image, the provided
            // key image is included and verified in a ring signature which
            // guarantees that 'the staker proves that he knows such 'x' (one time
            // ephemeral secret key) and that (the future key image) P = xG'.
            // Consequently the key image is not falsified and actually the future
            // key image.

            // The signer can try falsify the key image, but the equation used to
            // construct the key image is re-derived by the verifier, false key
            // images will not match the re-derived key image.
            for (auto proof = key_image_proofs.proofs.begin();
                 proof != key_image_proofs.proofs.end();
                 proof++) {
                if (!crypto::check_key_image_signature(
                            proof->key_image, ephemeral_pub_key, proof->signature))
                    continue;

                contribution->locked_contributions.emplace_back(
                        service_node_info::contribution_t::version_t::v0,
                        ephemeral_pub_key,
                        proof->key_image,
                        transferred);
                contribution->transferred += transferred;
                key_image_proofs.proofs.erase(proof);
                break;
            }
        }
    }

    if (hf_version < hf::hf11_infinite_staking) {
        // Pre Infinite Staking, we only need to prove the amount sent is
        // sufficient to become a contributor to the Service Node and that there
        // is sufficient lock time on the staking output.
        for (size_t i = 0; i < tx.vout.size(); i++) {
            bool has_correct_unlock_time = false;
            {
                uint64_t unlock_time = tx.unlock_time;
                if (tx.version >= cryptonote::txversion::v3_per_output_unlock_times)
                    unlock_time = tx.output_unlock_times[i];

                uint64_t min_height = block_height + staking_num_lock_blocks(nettype);
                has_correct_unlock_time =
                        unlock_time < cryptonote::MAX_BLOCK_NUMBER && unlock_time >= min_height;
            }

            if (has_correct_unlock_time) {
                contribution->transferred +=
                        get_staking_output_contribution(tx, i, derivation, hwdev);
                stake_decoded = true;
            }
        }
    }

    return stake_decoded;
}

/// Makes a copy of the given service_node_info and replaces the shared_ptr with a pointer to the
/// copy. Returns the non-const service_node_info (which is now held by the passed-in shared_ptr
/// lvalue ref).
static service_node_info& duplicate_info(std::shared_ptr<const service_node_info>& info_ptr) {
    auto new_ptr = std::make_shared<service_node_info>(*info_ptr);
    info_ptr = new_ptr;
    return *new_ptr;
}

bool service_node_list::state_t::process_state_change_tx(
        state_set const& state_history,
        state_set const& state_archive,
        std::unordered_map<crypto::hash, state_t> const& alt_states,
        cryptonote::network_type nettype,
        const cryptonote::block& block,
        const cryptonote::transaction& tx,
        const service_node_keys* my_keys) {
    if (tx.type != cryptonote::txtype::state_change)
        return false;

    const auto hf_version = block.major_version;
    cryptonote::tx_extra_service_node_state_change state_change;
    if (!cryptonote::get_service_node_state_change_from_tx_extra(
                tx.extra, state_change, hf_version)) {
        log::error(
                logcat,
                "Transaction: {}, did not have valid state change data in tx extra rejecting "
                "malformed tx",
                cryptonote::get_transaction_hash(tx));
        return false;
    }

    auto it = state_history.find(state_change.block_height);
    if (it == state_history.end()) {
        it = state_archive.find(state_change.block_height);
        if (it == state_archive.end()) {
            log::error(
                    logcat,
                    "Transaction: {} in block {} {} references quorum height but that height is "
                    "not stored!",
                    cryptonote::get_transaction_hash(tx),
                    cryptonote::get_block_height(block),
                    cryptonote::get_block_hash(block),
                    state_change.block_height);
            return false;
        }
    }

    quorum_manager const* quorums = &it->quorums;
    cryptonote::tx_verification_context tvc = {};
    if (!verify_tx_state_change(
                state_change,
                cryptonote::get_block_height(block),
                tvc,
                *quorums->obligations,
                hf_version)) {
        quorums = nullptr;
        for (const auto& [hash, alt_state] : alt_states) {
            if (alt_state.height != state_change.block_height)
                continue;

            quorums = &alt_state.quorums;
            if (!verify_tx_state_change(
                        state_change,
                        cryptonote::get_block_height(block),
                        tvc,
                        *quorums->obligations,
                        hf_version)) {
                quorums = nullptr;
                continue;
            }
        }
    }

    if (!quorums) {
        log::error(
                logcat,
                "Could not get a quorum that could completely validate the votes from state change "
                "in tx: {}, skipping transaction",
                get_transaction_hash(tx));
        return false;
    }

    crypto::public_key key;
    if (!get_pubkey_from_quorum(
                *quorums->obligations,
                quorum_group::worker,
                state_change.service_node_index,
                key)) {
        log::error(
                logcat,
                "Retrieving the public key from state change in tx: {} failed",
                cryptonote::get_transaction_hash(tx));
        return false;
    }

    auto iter = service_nodes_infos.find(key);
    if (iter == service_nodes_infos.end()) {
        log::debug(
                logcat,
                "Received state change tx for non-registered service node {} (perhaps a delayed "
                "tx?)",
                key);
        return false;
    }

    uint64_t block_height = cryptonote::get_block_height(block);
    auto& info = duplicate_info(iter->second);
    bool is_me = my_keys && my_keys->pub == key;

    switch (state_change.state) {
        case new_state::deregister:
            if (is_me)
                log::info(
                        logcat,
                        fg(fmt::terminal_color::red),
                        "Deregistration for service node (yours): {}",
                        key);
            else
                log::info(logcat, "Deregistration for service node: {}", key);

            if (hf_version >= hf::hf11_infinite_staking) {
                for (const auto& contributor : info.contributors) {
                    for (const auto& contribution : contributor.locked_contributions) {
                        key_image_blacklist.emplace_back();  // NOTE: Use default value for version
                                                             // in key_image_blacklist_entry
                        key_image_blacklist_entry& entry = key_image_blacklist.back();
                        entry.key_image = contribution.key_image;
                        entry.unlock_height = block_height + staking_num_lock_blocks(nettype);
                        entry.amount = contribution.amount;
                    }
                }
            }

            service_nodes_infos.erase(iter);
            return true;

        case new_state::decommission:
            if (hf_version < hf::hf12_checkpointing) {
                log::error(logcat, "Invalid decommission transaction seen before network v12");
                return false;
            }

            if (info.is_decommissioned()) {
                log::debug(
                        logcat,
                        "Received decommission tx for already-decommissioned service node {}; "
                        "ignoring",
                        key);
                return false;
            }

            if (is_me)
                log::info(
                        logcat,
                        fg(fmt::terminal_color::red),
                        "Temporary decommission for service node (yours): {}",
                        key);
            else
                log::info(logcat, "Temporary decommission for service node: {}", key);

            info.active_since_height = -info.active_since_height;
            info.last_decommission_height = block_height;
            info.last_decommission_reason_consensus_all = state_change.reason_consensus_all;
            info.last_decommission_reason_consensus_any = state_change.reason_consensus_any;
            info.decommission_count++;

            if (hf_version >= hf::hf13_enforce_checkpoints) {
                // Assigning invalid swarm id effectively kicks the node off
                // its current swarm; it will be assigned a new swarm id when it
                // gets recommissioned. Prior to HF13 this step was incorrectly
                // skipped.
                info.swarm_id = UNASSIGNED_SWARM_ID;
            }

            if (sn_list && !sn_list->m_rescanning) {
                auto& proof = sn_list->proofs[key];
                proof.timestamp = proof.effective_timestamp = 0;
                proof.store(key, sn_list->m_blockchain);
            }
            return true;

        case new_state::recommission: {
            if (hf_version < hf::hf12_checkpointing) {
                log::error(logcat, "Invalid recommission transaction seen before network v12");
                return false;
            }

            if (!info.is_decommissioned()) {
                log::debug(
                        logcat,
                        "Received recommission tx for already-active service node {}; ignoring",
                        key);
                return false;
            }

            if (is_me)
                log::info(
                        logcat,
                        fg(fmt::terminal_color::green),
                        "Recommission for service node (yours): {}",
                        key);
            else
                log::info(logcat, "Recommission for service node: {}", key);

            // To figure out how much credit the node gets at recommissioned we need to know how
            // much it had when it got decommissioned, and how long it's been decommisioned.
            int64_t credit_at_decomm =
                    quorum_cop::calculate_decommission_credit(info, info.last_decommission_height);
            int64_t decomm_blocks = block_height - info.last_decommission_height;

            info.active_since_height = block_height;
            info.recommission_credit = RECOMMISSION_CREDIT(credit_at_decomm, decomm_blocks);
            // Move the SN at the back of the list as if it had just registered (or just won)
            info.last_reward_block_height = block_height;
            info.last_reward_transaction_index = std::numeric_limits<uint32_t>::max();

            // NOTE: Only the quorum deciding on this node agrees that the service
            // node has a recent uptime atleast for it to be recommissioned not
            // necessarily the entire network. Ensure the entire network agrees
            // simultaneously they are online if we are recommissioning by resetting
            // the failure conditions.  We set only the effective but not *actual*
            // timestamp so that we delay obligations checks but don't prevent the
            // next actual proof from being sent/relayed.
            if (sn_list) {
                auto& proof = sn_list->proofs[key];
                proof.effective_timestamp = block.timestamp;
                proof.checkpoint_participation.reset();
                proof.pulse_participation.reset();
                proof.timestamp_participation.reset();
                proof.timesync_status.reset();
            }
            return true;
        }
        case new_state::ip_change_penalty:
            if (hf_version < hf::hf12_checkpointing) {
                log::error(logcat, "Invalid ip_change_penalty transaction seen before network v12");
                return false;
            }

            if (info.is_decommissioned()) {
                log::debug(
                        logcat,
                        "Received reset position tx for service node {} but it is already "
                        "decommissioned; ignoring",
                        key);
                return false;
            }

            if (is_me)
                log::info(
                        logcat,
                        fg(fmt::terminal_color::red),
                        "Reward position reset for service node (yours): {}",
                        key);
            else
                log::info(logcat, "Reward position reset for service node: {}", key);

            // Move the SN at the back of the list as if it had just registered (or just won)
            info.last_reward_block_height = block_height;
            info.last_reward_transaction_index = std::numeric_limits<uint32_t>::max();
            info.last_ip_change_height = block_height;
            return true;

        default:
            // dev bug!
            log::error(
                    logcat,
                    "BUG: Service node state change tx has unknown state {}",
                    static_cast<uint16_t>(state_change.state));
            return false;
    }
}

bool service_node_list::state_t::process_key_image_unlock_tx(
        cryptonote::network_type nettype,
        cryptonote::hf hf_version,
        uint64_t block_height,
        const cryptonote::transaction& tx) {
    crypto::public_key snode_key;
    if (!cryptonote::get_service_node_pubkey_from_tx_extra(tx.extra, snode_key))
        return false;

    auto it = service_nodes_infos.find(snode_key);
    if (it == service_nodes_infos.end())
        return false;

    const service_node_info& node_info = *it->second;
    if (node_info.requested_unlock_height != KEY_IMAGE_AWAITING_UNLOCK_HEIGHT) {
        log::info(
                logcat,
                "Unlock TX: Node already requested an unlock at height: {} rejected on height: {} "
                "for tx: {}",
                node_info.requested_unlock_height,
                block_height,
                cryptonote::get_transaction_hash(tx));
        return false;
    }

    cryptonote::tx_extra_tx_key_image_unlock unlock;
    if (!cryptonote::get_field_from_tx_extra(tx.extra, unlock)) {
        log::info(
                logcat,
                "Unlock TX: Didn't have key image unlock in the tx_extra, rejected on height: {} "
                "for tx: {}",
                block_height,
                cryptonote::get_transaction_hash(tx));
        return false;
    }

    uint64_t unlock_height = get_locked_key_image_unlock_height(
            nettype, node_info.registration_height, block_height);
    uint64_t small_contributor_amount_threshold = mul128_div64(
            service_nodes::get_staking_requirement(nettype, unlock_height),
            service_nodes::SMALL_CONTRIBUTOR_THRESHOLD::num,
            service_nodes::SMALL_CONTRIBUTOR_THRESHOLD::den);
    for (const auto& contributor : node_info.contributors) {
        auto cit = std::find_if(
                contributor.locked_contributions.begin(),
                contributor.locked_contributions.end(),
                [&unlock](const service_node_info::contribution_t& contribution) {
                    return unlock.key_image == contribution.key_image;
                });
        if (cit != contributor.locked_contributions.end()) {
            if (hf_version >= hf::hf20) {
                if (cit->amount < small_contributor_amount_threshold &&
                    (block_height - node_info.registration_height) <
                            service_nodes::SMALL_CONTRIBUTOR_UNLOCK_TIMER) {
                    log::info(
                            logcat,
                            "Unlock TX: small contributor trying to unlock node before {} blocks "
                            "have passed, rejected on height: {} for tx: {}",
                            std::to_string(service_nodes::SMALL_CONTRIBUTOR_UNLOCK_TIMER),
                            block_height,
                            get_transaction_hash(tx));
                    return false;
                }
            }
            // TODO oxen remove this whole if block after HF20 has occurred
            if (hf_version == hf::hf19_reward_batching) {
                if (cit->amount < 3749 && (block_height - node_info.registration_height) <
                                                  service_nodes::SMALL_CONTRIBUTOR_UNLOCK_TIMER) {
                    log::info(
                            logcat,
                            "Unlock TX: small contributor trying to unlock node before {} blocks "
                            "have passed, rejected on height: {} for tx: {}",
                            std::to_string(service_nodes::SMALL_CONTRIBUTOR_UNLOCK_TIMER),
                            block_height,
                            get_transaction_hash(tx));
                    return false;
                }
            }
            // NOTE(oxen): This should be checked in blockchain check_tx_inputs already
            if (crypto::check_signature(
                        service_nodes::generate_request_stake_unlock_hash(unlock.nonce),
                        cit->key_image_pub_key,
                        unlock.signature)) {
                duplicate_info(it->second).requested_unlock_height = unlock_height;
                return true;
            } else {
                log::info(
                        logcat,
                        "Unlock TX: Couldn't verify key image unlock in the tx_extra, rejected on "
                        "height: {} for tx: {}",
                        block_height,
                        get_transaction_hash(tx));
                return false;
            }
        }
    }

    return false;
}

//------------------------------------------------------------------
// TODO oxen remove this whole function after HF20 has occurred
bool service_node_list::state_t::is_premature_unlock(
        cryptonote::network_type nettype,
        cryptonote::hf hf_version,
        uint64_t block_height,
        const cryptonote::transaction& tx) const {
    if (hf_version != hf::hf19_reward_batching)
        return false;
    crypto::public_key snode_key;
    if (!cryptonote::get_service_node_pubkey_from_tx_extra(tx.extra, snode_key))
        return false;

    auto it = service_nodes_infos.find(snode_key);
    if (it == service_nodes_infos.end())
        return false;

    const service_node_info& node_info = *it->second;

    cryptonote::tx_extra_tx_key_image_unlock unlock;
    if (!cryptonote::get_field_from_tx_extra(tx.extra, unlock))
        return false;

    uint64_t unlock_height = get_locked_key_image_unlock_height(
            nettype, node_info.registration_height, block_height);
    uint64_t small_contributor_amount_threshold = mul128_div64(
            service_nodes::get_staking_requirement(nettype, block_height),
            service_nodes::SMALL_CONTRIBUTOR_THRESHOLD::num,
            service_nodes::SMALL_CONTRIBUTOR_THRESHOLD::den);
    for (const auto& contributor : node_info.contributors) {
        auto cit = std::find_if(
                contributor.locked_contributions.begin(),
                contributor.locked_contributions.end(),
                [&unlock](const service_node_info::contribution_t& contribution) {
                    return unlock.key_image == contribution.key_image;
                });
        if (cit != contributor.locked_contributions.end())
            return cit->amount < small_contributor_amount_threshold &&
                   (block_height - node_info.registration_height) <
                           service_nodes::SMALL_CONTRIBUTOR_UNLOCK_TIMER;
    }
    return false;
}

bool is_registration_tx(
        cryptonote::network_type nettype,
        hf hf_version,
        const cryptonote::transaction& tx,
        uint64_t block_timestamp,
        uint64_t block_height,
        uint32_t index,
        crypto::public_key& key,
        service_node_info& info) {
    auto maybe_reg = reg_tx_extract_fields(tx);
    if (!maybe_reg)
        return false;
    auto& reg = *maybe_reg;

    uint64_t staking_requirement = get_staking_requirement(nettype, block_height);
    try {
        validate_registration(hf_version, nettype, staking_requirement, block_timestamp, reg);
        validate_registration_signature(reg);
    } catch (const invalid_registration& e) {
        log::info(
                logcat,
                "Invalid registration ({} @ {}): {}",
                cryptonote::get_transaction_hash(tx),
                block_height,
                e.what());
        return false;
    }

    // check the operator contribution exists

    cryptonote::account_public_address address;

    staking_components stake = {};
    if (!tx_get_staking_components_and_amounts(nettype, hf_version, tx, block_height, &stake)) {
        log::info(
                logcat,
                "Register TX: Had service node registration fields, but could not decode "
                "contribution on height: {} for tx: {}",
                block_height,
                cryptonote::get_transaction_hash(tx));
        return false;
    }

    if (hf_version >= hf::hf16_pulse) {
        // In HF16 we start enforcing three things that were always done but weren't actually
        // enforced:
        // 1. the staked amount in the tx must be a single output.
        if (stake.locked_contributions.size() != 1) {
            log::info(
                    logcat,
                    "Register TX invalid: multi-output registration transactions are not permitted "
                    "as of HF16");
            return false;
        }

        // 2. the staked amount must be from the operator.  (Previously there was a weird edge case
        // where you could manually construct a registration tx that stakes for someone *other* than
        // the operator).
        if (stake.address != reg.reserved[0].first) {
            log::info(logcat, "Register TX invalid: registration stake is not from the operator");
            return false;
        }

        // 3. The operator must be staking at least his reserved amount in the registration details.
        // (We check this later, after we calculate reserved atomic currency amounts).  In the
        // pre-HF16 code below it only had to satisfy >= 25% even if the reserved operator stake was
        // higher.
    } else  // Pre-HF16
    {
        const uint64_t min_transfer =
                get_min_node_contribution(hf_version, staking_requirement, 0, 0);
        if (stake.transferred < min_transfer) {
            log::info(
                    logcat,
                    "Register TX: Contribution transferred: {} didn't meet the minimum transfer "
                    "requirement: {} on height: {} for tx: {}",
                    stake.transferred,
                    min_transfer,
                    block_height,
                    cryptonote::get_transaction_hash(tx));
            return false;
        }

        size_t total_num_of_addr = reg.reserved.size();
        if (std::find_if(reg.reserved.begin(), reg.reserved.end(), [&](auto& addr_amt) {
                return addr_amt.first == stake.address;
            }) == reg.reserved.end())
            total_num_of_addr++;

        // Don't need this check for HF16+ because the number of reserved spots is already checked
        // in the registration details, and we disallow a non-operator registration.
        if (total_num_of_addr > oxen::MAX_CONTRIBUTORS_V1) {
            log::info(
                    logcat,
                    "Register TX: Number of participants: {} exceeded the max number of "
                    "contributions: {} on height: {} for tx: {}",
                    total_num_of_addr,
                    oxen::MAX_CONTRIBUTORS_V1,
                    block_height,
                    cryptonote::get_transaction_hash(tx));
            return false;
        }
    }

    // don't actually process this contribution now, do it when we fall through later.

    key = reg.service_node_pubkey;

    info.staking_requirement = staking_requirement;
    info.operator_address = reg.reserved[0].first;

    if (reg.uses_portions)
        info.portions_for_operator = reg.fee;
    else
        info.portions_for_operator = mul128_div64(
                reg.fee, cryptonote::old::STAKING_PORTIONS, cryptonote::STAKING_FEE_BASIS);

    info.registration_height = block_height;
    info.registration_hf_version = hf_version;
    info.last_reward_block_height = block_height;
    info.last_reward_transaction_index = index;
    info.swarm_id = UNASSIGNED_SWARM_ID;
    info.last_ip_change_height = block_height;

    for (auto it = reg.reserved.begin(); it != reg.reserved.end(); ++it) {
        auto& [addr, amount] = *it;
        bool dupe = false;
        for (auto it2 = std::next(it); it2 != reg.reserved.end(); ++it2) {
            if (it2->first == addr) {
                log::info(
                        logcat,
                        "Invalid registration: duplicate reserved address in registration (tx {})",
                        cryptonote::get_transaction_hash(tx));
                return false;
            }
        }

        auto& contributor = info.contributors.emplace_back();
        if (reg.uses_portions)
            contributor.reserved = mul128_div64(
                    amount, info.staking_requirement, cryptonote::old::STAKING_PORTIONS);
        else
            contributor.reserved = amount;

        contributor.address = addr;
        info.total_reserved += contributor.reserved;
    }

    // In HF16 we require that the amount staked in the registration tx be at least the amount
    // reserved for the operator.  Before HF16 it only had to be >= 25%, even if the operator
    // reserved amount was higher (though wallets would never actually do this).
    if (hf_version >= hf::hf16_pulse && stake.transferred < info.contributors[0].reserved) {
        log::info(logcat, "Register TX rejected: TX does not have sufficient operator stake");
        return false;
    }

    return true;
}

bool service_node_list::state_t::process_registration_tx(
        cryptonote::network_type nettype,
        const cryptonote::block& block,
        const cryptonote::transaction& tx,
        uint32_t index,
        const service_node_keys* my_keys) {
    const auto hf_version = block.major_version;
    uint64_t const block_timestamp = block.timestamp;
    uint64_t const block_height = cryptonote::get_block_height(block);

    crypto::public_key key;
    auto info_ptr = std::make_shared<service_node_info>();
    service_node_info& info = *info_ptr;
    if (!is_registration_tx(
                nettype, hf_version, tx, block_timestamp, block_height, index, key, info))
        return false;

    if (hf_version >= hf::hf11_infinite_staking) {
        // NOTE(oxen): Grace period is not used anymore with infinite staking. So, if someone
        // somehow reregisters, we just ignore it
        const auto iter = service_nodes_infos.find(key);
        if (iter != service_nodes_infos.end())
            return false;

        // Explicitly reset any stored proof to 0, and store it just in case this is a
        // re-registration: we want to wipe out any data from the previous registration.
        if (sn_list && !sn_list->m_rescanning) {
            auto& proof = sn_list->proofs[key];
            proof = {};
            proof.store(key, sn_list->m_blockchain);
        }

        if (my_keys && my_keys->pub == key)
            log::info(
                    logcat,
                    fg(fmt::terminal_color::green),
                    "Service node registered (yours): {} on height: {}",
                    key,
                    block_height);
        else
            log::info(logcat, "New service node registered: {} on height: {}", key, block_height);
    } else {
        // NOTE: A node doesn't expire until registration_height + lock blocks excess now which acts
        // as the grace period So it is possible to find the node still in our list.
        bool registered_during_grace_period = false;
        const auto iter = service_nodes_infos.find(key);
        if (iter != service_nodes_infos.end()) {
            if (hf_version >= hf::hf10_bulletproofs) {
                service_node_info const& old_info = *iter->second;
                uint64_t expiry_height =
                        old_info.registration_height + staking_num_lock_blocks(nettype);
                if (block_height < expiry_height)
                    return false;

                // NOTE: Node preserves its position in list if it reregisters during grace period.
                registered_during_grace_period = true;
                info.last_reward_block_height = old_info.last_reward_block_height;
                info.last_reward_transaction_index = old_info.last_reward_transaction_index;
            } else {
                return false;
            }
        }

        if (my_keys && my_keys->pub == key) {
            if (registered_during_grace_period) {
                log::info(
                        logcat,
                        fg(fmt::terminal_color::green),
                        "Service node re-registered (yours): {} at block height: {}",
                        key,
                        block_height);
            } else {
                log::info(
                        logcat,
                        fg(fmt::terminal_color::green),
                        "Service node registered (yours): {} at block height: {}",
                        key,
                        block_height);
            }
        } else {
            log::info(
                    logcat,
                    "New service node registered: {} at block height: {}",
                    key,
                    block_height);
        }
    }

    service_nodes_infos[key] = std::move(info_ptr);
    return true;
}

bool service_node_list::state_t::process_contribution_tx(
        cryptonote::network_type nettype,
        const cryptonote::block& block,
        const cryptonote::transaction& tx,
        uint32_t index) {
    uint64_t const block_height = cryptonote::get_block_height(block);
    const auto hf_version = block.major_version;

    staking_components stake = {};
    if (!tx_get_staking_components_and_amounts(nettype, hf_version, tx, block_height, &stake)) {
        if (stake.service_node_pubkey)
            log::info(
                    logcat,
                    "TX: Could not decode contribution for service node: {} on height: {} for tx: "
                    "{}",
                    stake.service_node_pubkey,
                    block_height,
                    cryptonote::get_transaction_hash(tx));
        return false;
    }

    auto iter = service_nodes_infos.find(stake.service_node_pubkey);
    if (iter == service_nodes_infos.end()) {
        log::info(
                logcat,
                "TX: Contribution received for service node: {}, but could not be found in the "
                "service node list on height: {} for tx: {}\n This could mean that the service "
                "node was deregistered before the contribution was processed.",
                stake.service_node_pubkey,
                block_height,
                cryptonote::get_transaction_hash(tx));
        return false;
    }

    const service_node_info& curinfo = *iter->second;
    if (curinfo.is_fully_funded()) {
        log::info(
                logcat,
                "TX: Service node: {} is already fully funded, but contribution received on "
                "height: {} for tx: {}",
                stake.service_node_pubkey,
                block_height,
                cryptonote::get_transaction_hash(tx));
        return false;
    }

    if (!cryptonote::get_tx_secret_key_from_tx_extra(tx.extra, stake.tx_key)) {
        log::info(
                logcat,
                "TX: Failed to get tx secret key from contribution received on height: {} for tx: "
                "{}",
                block_height,
                cryptonote::get_transaction_hash(tx));
        return false;
    }

    auto& contributors = curinfo.contributors;
    const size_t existing_contributions = curinfo.total_num_locked_contributions();
    size_t other_reservations = 0;  // Number of spots that must be left open, *not* counting this
                                    // contributor (if they have a reserved spot)
    bool new_contributor = true;
    size_t contributor_position = 0;
    uint64_t contr_unfilled_reserved = 0;
    for (size_t i = 0; i < contributors.size(); i++) {
        const auto& c = contributors[i];
        if (c.address == stake.address) {
            contributor_position = i;
            new_contributor = false;
            if (c.amount < c.reserved)
                contr_unfilled_reserved = c.reserved - c.amount;
        } else if (c.amount < c.reserved)
            other_reservations++;
    }

    if (hf_version >= hf::hf16_pulse && stake.locked_contributions.size() != 1) {
        // Nothing has ever created stake txes with multiple stake outputs, but we start enforcing
        // that in HF16.
        log::info(logcat, "Ignoring staking tx: multi-output stakes are not permitted as of HF16");
        return false;
    }

    // Check node contributor counts
    {
        bool too_many_contributions = false;
        if (hf_version >= hf::hf19_reward_batching)
            // As of HF19 we allow up to 10 stakes total
            too_many_contributions =
                    existing_contributions + other_reservations + 1 > oxen::MAX_CONTRIBUTORS_HF19;
        else if (hf_version >= hf::hf16_pulse)
            // Before HF16 we didn't properly take into account unfilled reservation spots
            too_many_contributions =
                    existing_contributions + other_reservations + 1 > oxen::MAX_CONTRIBUTORS_V1;
        else if (hf_version >= hf::hf11_infinite_staking)
            // As of HF11 we allow up to 4 stakes total (except for the loophole closed above)
            too_many_contributions = existing_contributions + stake.locked_contributions.size() >
                                     oxen::MAX_CONTRIBUTORS_V1;
        else
            // Before HF11 we allowed up to 4 contributors, but each can contribute multiple times
            too_many_contributions =
                    new_contributor && contributors.size() >= oxen::MAX_CONTRIBUTORS_V1;

        if (too_many_contributions) {
            log::info(
                    logcat,
                    "TX: Already hit the max number of contributions: {} for contributor: {} on "
                    "height: {} for tx: {}",
                    (hf_version >= hf::hf19_reward_batching ? oxen::MAX_CONTRIBUTORS_HF19
                                                            : oxen::MAX_CONTRIBUTORS_V1),
                    cryptonote::get_account_address_as_str(nettype, false, stake.address),
                    block_height,
                    cryptonote::get_transaction_hash(tx));
            return false;
        }
    }

    // Check that the contribution is large enough
    uint64_t min_contribution;
    if (!new_contributor &&
        hf_version < hf::hf11_infinite_staking) {  // Follow-up contributions from an existing
                                                   // contributor could be any size before HF11
        min_contribution = 1;
    } else if (hf_version < hf::hf16_pulse) {
        // The implementation before HF16 was a bit broken w.r.t. properly handling reserved amounts
        min_contribution = get_min_node_contribution(
                hf_version,
                curinfo.staking_requirement,
                curinfo.total_reserved,
                existing_contributions);
    } else  // HF16+:
    {
        if (contr_unfilled_reserved > 0)
            // We've got a reserved spot: require that it be filled in one go.  (Reservation
            // contribution rules are already enforced in the registration).
            min_contribution = contr_unfilled_reserved;
        else
            min_contribution = get_min_node_contribution(
                    hf_version,
                    curinfo.staking_requirement,
                    curinfo.total_reserved,
                    existing_contributions + other_reservations);
    }

    if (stake.transferred < min_contribution) {
        log::info(
                logcat,
                "TX: Amount {} did not meet min {} for service node: {} on height: {} for tx: {}",
                stake.transferred,
                min_contribution,
                stake.service_node_pubkey,
                block_height,
                cryptonote::get_transaction_hash(tx));
        return false;
    }

    // Check that the contribution isn't too large.  Subtract contr_unfilled_reserved because we
    // want to calculate this using only the total reserved amounts of *other* contributors but not
    // our own.
    if (auto max = get_max_node_contribution(
                hf_version,
                curinfo.staking_requirement,
                curinfo.total_reserved - contr_unfilled_reserved);
        stake.transferred > max) {
        log::info(
                logcat,
                "TX: Amount {} is too large (max {}).  This is probably a result of competing "
                "stakes.",
                stake.transferred,
                max);
        return false;
    }

    //
    // Successfully Validated
    //

    auto& info = duplicate_info(iter->second);
    if (new_contributor) {
        contributor_position = info.contributors.size();
        info.contributors.emplace_back().address = stake.address;
    }
    service_node_info::contributor_t& contributor = info.contributors[contributor_position];

    // In this action, we cannot
    // increase total_reserved so much that it is >= staking_requirement
    uint64_t can_increase_reserved_by = info.staking_requirement - info.total_reserved;
    uint64_t max_amount = contributor.reserved + can_increase_reserved_by;
    stake.transferred = std::min(max_amount - contributor.amount, stake.transferred);

    contributor.amount += stake.transferred;
    info.total_contributed += stake.transferred;

    if (contributor.amount > contributor.reserved) {
        info.total_reserved += contributor.amount - contributor.reserved;
        contributor.reserved = contributor.amount;
    }

    info.last_reward_block_height = block_height;
    info.last_reward_transaction_index = index;

    if (hf_version >= hf::hf11_infinite_staking)
        for (const auto& contribution : stake.locked_contributions)
            contributor.locked_contributions.push_back(contribution);

    log::info(
            logcat,
            "Contribution of {} received for service node {}",
            stake.transferred,
            stake.service_node_pubkey);
    if (info.is_fully_funded()) {
        info.active_since_height = block_height;
        return true;
    }
    return false;
}

static std::string dump_pulse_block_data(
        cryptonote::block const& block, service_nodes::quorum const* quorum) {
    std::bitset<8 * sizeof(block.pulse.validator_bitset)> const validator_bitset =
            block.pulse.validator_bitset;
    std::string s =
            "Block({}): {}\nLeader: {}\nRound: {:d}\nValidator Bitset: {}\nSignatures:"_format(
                    cryptonote::get_block_height(block),
                    cryptonote::get_block_hash(block),
                    !quorum                   ? "(invalid quorum)"
                    : quorum->workers.empty() ? "(invalid leader)"
                                              : oxenc::to_hex(tools::view_guts(quorum->workers[0])),
                    validator_bitset.to_string());
    auto append = std::back_inserter(s);
    if (block.signatures.empty())
        fmt::format_to(append, " (none)");
    for (const auto& sig : block.signatures) {
        fmt::format_to(
                append,
                "\n  [{:d}] validator: {}",
                sig.voter_index,
                !quorum ? "(invalid quorum)"
                : sig.voter_index >= quorum->validators.size()
                        ? "(invalid quorum index)"
                        : "{}: {}"_format(quorum->validators[sig.voter_index], sig.signature));
    }
    return s;
}

static bool verify_block_components(
        cryptonote::network_type nettype,
        cryptonote::block const& block,
        bool miner_block,
        bool alt_block,
        bool log_errors,
        pulse::timings& timings,
        std::shared_ptr<const quorum> pulse_quorum,
        std::vector<std::shared_ptr<const quorum>>& alt_pulse_quorums) {
    std::string_view block_type = alt_block ? "alt block"sv : "block"sv;
    uint64_t height = cryptonote::get_block_height(block);
    crypto::hash hash = cryptonote::get_block_hash(block);

    if (miner_block) {

        if (cryptonote::block_has_pulse_components(block)) {
            if (log_errors)
                log::info(
                        logcat,
                        "Pulse {} received but only miner blocks are permitted\n{}",
                        block_type,
                        dump_pulse_block_data(block, pulse_quorum.get()));
            return false;
        }

        if (block.pulse.round != 0) {
            if (log_errors)
                log::info(
                        logcat,
                        "Miner {} given but unexpectedly set round {} on height {}",
                        block_type,
                        block.pulse.round,
                        height);
            return false;
        }

        if (block.pulse.validator_bitset != 0) {
            std::bitset<8 * sizeof(block.pulse.validator_bitset)> const bitset =
                    block.pulse.validator_bitset;
            if (log_errors)
                log::info(
                        logcat,
                        "Miner {} block given but unexpectedly set validator bitset {} on height "
                        "{}",
                        block_type,
                        bitset.to_string(),
                        height);
            return false;
        }

        if (block.signatures.size()) {
            if (log_errors)
                log::info(
                        logcat,
                        "Miner {} block given but unexpectedly has {} signatures on height {}",
                        block_type,
                        block.signatures.size(),
                        height);
            return false;
        }

        return true;
    } else {
        if (!cryptonote::block_has_pulse_components(block)) {
            if (log_errors)
                log::info(
                        logcat,
                        "Miner {} received but only pulse blocks are permitted\n{}",
                        block_type,
                        dump_pulse_block_data(block, pulse_quorum.get()));
            return false;
        }

        // TODO(doyle): Core tests need to generate coherent timestamps with
        // Pulse. So we relax the rules here for now.
        if (nettype != cryptonote::network_type::FAKECHAIN) {
            auto round_begin_timestamp =
                    timings.r0_timestamp + (block.pulse.round * PULSE_ROUND_TIME);
            auto round_end_timestamp = round_begin_timestamp + PULSE_ROUND_TIME;

            uint64_t begin_time = tools::to_seconds(round_begin_timestamp.time_since_epoch());
            uint64_t end_time = tools::to_seconds(round_end_timestamp.time_since_epoch());
            if (!(block.timestamp >= begin_time && block.timestamp <= end_time)) {
                std::string time = tools::get_human_readable_timestamp(block.timestamp);
                std::string begin = tools::get_human_readable_timestamp(begin_time);
                std::string end = tools::get_human_readable_timestamp(end_time);
                if (log_errors)
                    log::info(
                            logcat,
                            "Pulse {} with round {} specifies timestamp {} is not within an "
                            "acceptable range of time [{}, {}]",
                            block_type,
                            +block.pulse.round,
                            time,
                            begin,
                            end);
                return false;
            }
        }

        if (block.nonce != 0) {
            if (log_errors)
                log::info(
                        logcat,
                        "Pulse {} specified a nonce when quorum block generation is available, "
                        "nonce: {}",
                        block_type,
                        block.nonce);
            return false;
        }

        bool quorum_verified = false;
        if (alt_block) {
            // NOTE: Check main pulse quorum. It might not necessarily exist because
            // the alt-block's chain could be in any arbitrary state.
            bool failed_quorum_verify = true;
            if (pulse_quorum) {
                log::info(
                        logcat,
                        "Verifying alt-block {}:{} against main chain quorum",
                        height,
                        hash);
                failed_quorum_verify = service_nodes::verify_quorum_signatures(
                                               *pulse_quorum,
                                               quorum_type::pulse,
                                               block.major_version,
                                               height,
                                               hash,
                                               block.signatures,
                                               &block) == false;
            }

            // NOTE: Check alt pulse quorums
            if (failed_quorum_verify) {
                log::info(
                        logcat,
                        "Verifying alt-block {}:{} against alt chain quorum(s)",
                        height,
                        hash);
                for (auto const& alt_quorum : alt_pulse_quorums) {
                    if (service_nodes::verify_quorum_signatures(
                                *alt_quorum,
                                quorum_type::pulse,
                                block.major_version,
                                height,
                                hash,
                                block.signatures,
                                &block)) {
                        failed_quorum_verify = false;
                        break;
                    }
                }
            }

            quorum_verified = !failed_quorum_verify;
        } else {
            // NOTE: We only accept insufficient node for Pulse if we're on an alt
            // block (that chain would be in any arbitrary state, we could be
            // completely isolated from the correct network for example).
            bool insufficient_nodes_for_pulse = pulse_quorum == nullptr;
            if (insufficient_nodes_for_pulse) {
                if (log_errors)
                    log::info(
                            logcat,
                            "Pulse {} specified but no quorum available {}",
                            block_type,
                            dump_pulse_block_data(block, pulse_quorum.get()));
                return false;
            }

            quorum_verified = service_nodes::verify_quorum_signatures(
                    *pulse_quorum,
                    quorum_type::pulse,
                    block.major_version,
                    cryptonote::get_block_height(block),
                    cryptonote::get_block_hash(block),
                    block.signatures,
                    &block);
        }

        if (quorum_verified) {
            // NOTE: These invariants are already checked in verify_quorum_signatures
            if (alt_block)
                log::info(logcat, "Alt-block {}:{} verified successfully", height, hash);
            assert(block.pulse.validator_bitset != 0);
            assert(block.pulse.validator_bitset < (1 << PULSE_QUORUM_NUM_VALIDATORS));
            assert(block.signatures.size() == service_nodes::PULSE_BLOCK_REQUIRED_SIGNATURES);
        } else {
            if (log_errors)
                log::info(
                        logcat,
                        "Pulse {} failed quorum verification\n{}",
                        block_type,
                        dump_pulse_block_data(block, pulse_quorum.get()));
        }

        return quorum_verified;
    }
}

static bool find_block_in_db(
        cryptonote::BlockchainDB const& db, crypto::hash const& hash, cryptonote::block& block) {
    try {
        block = db.get_block(hash);
    } catch (std::exception const& e) {
        // ignore not found block, try alt db
        log::info(logcat, "Block {} not found in main DB, searching alt DB", hash);
        cryptonote::alt_block_data_t alt_data;
        std::string blob;
        if (!db.get_alt_block(hash, &alt_data, &blob, nullptr)) {
            log::error(logcat, "Failed to find block {}", hash);
            return false;
        }

        if (!cryptonote::parse_and_validate_block_from_blob(blob, block, nullptr)) {
            log::error(logcat, "Failed to parse alt block blob at {}:{}", alt_data.height, hash);
            return false;
        }
    }

    return true;
}

void service_node_list::verify_block(
        const cryptonote::block& block,
        bool alt_block,
        cryptonote::checkpoint_t const* checkpoint) {
    if (block.major_version < hf::hf9_service_nodes)
        return;

    std::string_view block_type = alt_block ? "alt block"sv : "block"sv;

    //
    // NOTE: Verify the checkpoint given on this height that locks in a block in the past.
    //
    if (block.major_version >= hf::hf13_enforce_checkpoints && checkpoint) {
        std::vector<std::shared_ptr<const service_nodes::quorum>> alt_quorums;
        std::shared_ptr<const quorum> quorum = get_quorum(
                quorum_type::checkpointing,
                checkpoint->height,
                false,
                alt_block ? &alt_quorums : nullptr);

        if (!quorum)
            throw std::runtime_error{"Failed to get testing quorum checkpoint for {} {}"_format(
                    block_type, cryptonote::get_block_hash(block))};

        bool failed_checkpoint_verify =
                !service_nodes::verify_checkpoint(block.major_version, *checkpoint, *quorum);
        if (alt_block && failed_checkpoint_verify) {
            for (std::shared_ptr<const service_nodes::quorum> alt_quorum : alt_quorums) {
                if (service_nodes::verify_checkpoint(
                            block.major_version, *checkpoint, *alt_quorum)) {
                    failed_checkpoint_verify = false;
                    break;
                }
            }
        }

        if (failed_checkpoint_verify)
            throw std::runtime_error{"Service node checkpoint failed verification for {} {}"_format(
                    block_type, cryptonote::get_block_hash(block))};
    }

    //
    // NOTE: Get Pulse Block Timing Information
    //
    pulse::timings timings = {};
    uint64_t height = cryptonote::get_block_height(block);
    if (block.major_version >= hf::hf16_pulse) {
        uint64_t prev_timestamp = 0;
        if (alt_block) {
            cryptonote::block prev_block;
            if (!find_block_in_db(m_blockchain.get_db(), block.prev_id, prev_block))
                throw std::runtime_error{
                        "Alt block {} references previous block {} not available in DB."_format(
                                cryptonote::get_block_hash(block), block.prev_id)};

            prev_timestamp = prev_block.timestamp;
        } else {
            uint64_t prev_height = height - 1;
            prev_timestamp = m_blockchain.get_db().get_block_timestamp(prev_height);
        }

        if (!pulse::get_round_timings(m_blockchain, height, prev_timestamp, timings))
            throw std::runtime_error{
                    "Failed to query the block data for Pulse timings to validate incoming {} at height {}"_format(
                            block_type, height)};
    }

    //
    // NOTE: Load Pulse Quorums
    //
    std::shared_ptr<const quorum> pulse_quorum;
    std::vector<std::shared_ptr<const quorum>> alt_pulse_quorums;
    bool pulse_hf = block.major_version >= hf::hf16_pulse;

    if (pulse_hf) {
        pulse_quorum = get_quorum(
                quorum_type::pulse,
                height,
                false /*include historical quorums*/,
                alt_block ? &alt_pulse_quorums : nullptr);
    }

    if (m_blockchain.nettype() != cryptonote::network_type::FAKECHAIN) {
        // TODO(doyle): Core tests don't generate proper timestamps for detecting
        // timeout yet. So we don't do a timeout check and assume all blocks
        // incoming from Pulse are valid if they have the correct signatures
        // (despite timestamp being potentially wrong).
        if (pulse::time_point(std::chrono::seconds(block.timestamp)) >=
            timings.miner_fallback_timestamp)
            pulse_quorum = nullptr;
    }

    //
    // NOTE: Verify Block
    //
    bool result = false;
    if (alt_block) {
        // NOTE: Verify as a pulse block first if possible, then as a miner block.
        // This alt block could belong to a chain that is in an arbitrary state.
        if (pulse_hf)
            result = verify_block_components(
                    m_blockchain.nettype(),
                    block,
                    false /*miner_block*/,
                    true /*alt_block*/,
                    false /*log_errors*/,
                    timings,
                    pulse_quorum,
                    alt_pulse_quorums);

        if (!result)
            result = verify_block_components(
                    m_blockchain.nettype(),
                    block,
                    true /*miner_block*/,
                    true /*alt_block*/,
                    false /*log_errors*/,
                    timings,
                    pulse_quorum,
                    alt_pulse_quorums);
    } else {
        // NOTE: No pulse quorums are generated when the network has insufficient nodes to generate
        // quorums
        //       Or, block specifies time after all the rounds have timed out
        bool miner_block = !pulse_hf || !pulse_quorum;

        result = verify_block_components(
                m_blockchain.nettype(),
                block,
                miner_block,
                false /*alt_block*/,
                true /*log_errors*/,
                timings,
                pulse_quorum,
                alt_pulse_quorums);
    }

    if (!result)
        throw std::runtime_error{
                "Failed to verify block components for incoming {} at height {}"_format(
                        block_type, height)};
}

void service_node_list::block_add(
        const cryptonote::block& block,
        const std::vector<cryptonote::transaction>& txs,
        cryptonote::checkpoint_t const* checkpoint) {
    if (block.major_version < hf::hf9_service_nodes)
        return;

    std::lock_guard lock(m_sn_mutex);
    process_block(block, txs);
    verify_block(block, false /*alt_block*/, checkpoint);
    if (cryptonote::block_has_pulse_components(block)) {
        // NOTE: Only record participation if its a block we recently received.
        // Otherwise processing blocks in retrospect/re-loading on restart seeds
        // in old-data.
        uint64_t const block_height = cryptonote::get_block_height(block);
        bool newest_block = m_blockchain.get_current_blockchain_height() == (block_height + 1);

        auto now = pulse::clock::now().time_since_epoch();
        auto earliest_time = std::chrono::seconds(block.timestamp) - cryptonote::TARGET_BLOCK_TIME;
        auto latest_time = std::chrono::seconds(block.timestamp) + cryptonote::TARGET_BLOCK_TIME;

        if (newest_block && (now >= earliest_time && now <= latest_time)) {
            std::shared_ptr<const quorum> quorum =
                    get_quorum(quorum_type::pulse, block_height, false, nullptr);
            if (!quorum)
                throw std::runtime_error{"Unexpected Pulse error: quorum was not generated"};
            if (quorum->validators.empty())
                throw std::runtime_error{"Unexpected Pulse error: quorum was empty"};

            for (size_t validator_index = 0;
                 validator_index < service_nodes::PULSE_QUORUM_NUM_VALIDATORS;
                 validator_index++) {
                uint16_t bit = 1 << validator_index;
                bool participated = block.pulse.validator_bitset & bit;
                record_pulse_participation(
                        quorum->validators[validator_index],
                        block_height,
                        block.pulse.round,
                        participated);
            }
        }
    }
}

bool service_node_list::state_history_exists(uint64_t height) {
    auto it = m_transient.state_history.find(height);
    return it != m_transient.state_history.end();
}

bool service_node_list::process_batching_rewards(const cryptonote::block& block) {
    uint64_t block_height = cryptonote::get_block_height(block);
    if (m_blockchain.nettype() != cryptonote::network_type::FAKECHAIN &&
        block.major_version >= hf::hf19_reward_batching && height() != block_height) {
        log::error(
                logcat,
                "Service node list out of sync with the batching database, adding block will fail "
                "because the service node list is at height: {} and the batching database is at "
                "height: {}",
                height(),
                m_blockchain.sqlite_db()->height + 1);
        return false;
    }
    return m_blockchain.sqlite_db()->add_block(block, m_state);
}
bool service_node_list::pop_batching_rewards_block(const cryptonote::block& block) {
    uint64_t block_height = cryptonote::get_block_height(block);
    if (m_blockchain.nettype() != cryptonote::network_type::FAKECHAIN &&
        block.major_version >= hf::hf19_reward_batching && height() != block_height) {
        if (auto it = m_transient.state_history.find(block_height);
            it != m_transient.state_history.end())
            return m_blockchain.sqlite_db()->pop_block(block, *it);
        m_blockchain.sqlite_db()->reset_database();
        return false;
    }
    return m_blockchain.sqlite_db()->pop_block(block, m_state);
}

static std::mt19937_64 quorum_rng(hf hf_version, crypto::hash const& hash, quorum_type type) {
    std::mt19937_64 result;
    if (hf_version >= hf::hf16_pulse) {
        std::array<uint32_t, (sizeof(hash) / sizeof(uint32_t)) + 1> src = {
                static_cast<uint32_t>(type)};
        std::memcpy(&src[1], &hash, sizeof(hash));
        for (uint32_t& val : src)
            oxenc::little_to_host_inplace(val);
        std::seed_seq sequence(src.begin(), src.end());
        result.seed(sequence);
    } else {
        uint64_t seed = 0;
        std::memcpy(&seed, hash.data(), sizeof(seed));
        oxenc::little_to_host_inplace(seed);
        seed += static_cast<uint64_t>(type);
        result.seed(seed);
    }

    return result;
}

static std::vector<size_t> generate_shuffled_service_node_index_list(
        hf hf_version,
        size_t list_size,
        crypto::hash const& block_hash,
        quorum_type type,
        size_t sublist_size = 0,
        size_t sublist_up_to = 0) {
    std::vector<size_t> result(list_size);
    std::iota(result.begin(), result.end(), 0);
    std::mt19937_64 rng = quorum_rng(hf_version, block_hash, type);

    //       Shuffle 2
    //       |=================================|
    //       |                                 |
    // Shuffle 1                               |
    // |==============|                        |
    // |     |        |                        |
    // |sublist_size  |                        |
    // |     |    sublist_up_to                |
    // 0     N        Y                        Z
    // [.......................................]

    // If we have a list [0,Z) but we need a shuffled sublist of the first N values that only
    // includes values from [0,Y) then we do this using two shuffles: first of the [0,Y) sublist,
    // then of the [N,Z) sublist (which is already partially shuffled, but that doesn't matter).  We
    // reuse the same seed for both partial shuffles, but again, that isn't an issue.
    if ((0 < sublist_size && sublist_size < list_size) &&
        (0 < sublist_up_to && sublist_up_to < list_size)) {
        assert(sublist_size <=
               sublist_up_to);  // Can't select N random items from M items when M < N
        auto rng_copy = rng;
        tools::shuffle_portable(result.begin(), result.begin() + sublist_up_to, rng);
        tools::shuffle_portable(result.begin() + sublist_size, result.end(), rng_copy);
    } else {
        tools::shuffle_portable(result.begin(), result.end(), rng);
    }
    return result;
}

template <typename It>
static std::vector<crypto::hash> make_pulse_entropy_from_blocks(
        It begin, It end, uint8_t pulse_round) {
    std::vector<crypto::hash> result;
    result.reserve(std::distance(begin, end));

    for (auto it = begin; it != end; it++) {
        cryptonote::block const& block = *it;
        crypto::hash hash = {};
        if (block.major_version >= hf::hf16_pulse &&
            cryptonote::block_has_pulse_components(block)) {
            std::array<uint8_t, 1 + sizeof(block.pulse.random_value)> src = {pulse_round};
            std::copy(
                    std::begin(block.pulse.random_value.data),
                    std::end(block.pulse.random_value.data),
                    src.begin() + 1);
            crypto::cn_fast_hash(src.data(), src.size(), hash);
        } else {
            crypto::hash block_hash = cryptonote::get_block_hash(block);
            std::array<uint8_t, 1 + sizeof(hash)> src = {pulse_round};
            std::copy(std::begin(block_hash), std::end(block_hash), src.begin() + 1);
            crypto::cn_fast_hash(src.data(), src.size(), hash);
        }

        assert(hash);
        result.push_back(hash);
    }

    return result;
}

std::vector<crypto::hash> get_pulse_entropy_for_next_block(
        cryptonote::BlockchainDB const& db,
        cryptonote::block const& top_block,
        uint8_t pulse_round) {
    uint64_t const top_height = cryptonote::get_block_height(top_block);
    if (top_height < PULSE_QUORUM_ENTROPY_LAG) {
        log::error(
                logcat,
                "Insufficient blocks to get quorum entropy for Pulse, height is {}, we need {} "
                "blocks.",
                top_height,
                PULSE_QUORUM_ENTROPY_LAG);
        return {};
    }

    uint64_t const start_height = top_height - PULSE_QUORUM_ENTROPY_LAG;
    uint64_t const end_height = start_height + PULSE_QUORUM_SIZE;

    std::vector<cryptonote::block> blocks;
    blocks.reserve(PULSE_QUORUM_SIZE);

    // NOTE: Go backwards from the block and retrieve the blocks for entropy.
    // We search by block so that this function handles alternatives blocks as
    // well as mainchain blocks.
    crypto::hash prev_hash = top_block.prev_id;
    uint64_t prev_height = top_height;
    while (prev_height > start_height) {
        cryptonote::block block;
        if (!find_block_in_db(db, prev_hash, block)) {
            log::error(
                    logcat,
                    "Failed to get quorum entropy for Pulse, block at {}{}",
                    prev_height,
                    prev_hash);
            return {};
        }

        prev_hash = block.prev_id;
        if (prev_height >= start_height && prev_height <= end_height)
            blocks.push_back(block);

        prev_height--;
    }

    return make_pulse_entropy_from_blocks(blocks.rbegin(), blocks.rend(), pulse_round);
}

std::vector<crypto::hash> get_pulse_entropy_for_next_block(
        cryptonote::BlockchainDB const& db, crypto::hash const& top_hash, uint8_t pulse_round) {
    cryptonote::block top_block;
    if (!find_block_in_db(db, top_hash, top_block)) {
        log::error(
                logcat, "Failed to get quorum entropy for Pulse, next block parent {}", top_hash);
        return {};
    }

    return get_pulse_entropy_for_next_block(db, top_block, pulse_round);
}

std::vector<crypto::hash> get_pulse_entropy_for_next_block(
        cryptonote::BlockchainDB const& db, uint8_t pulse_round) {
    return get_pulse_entropy_for_next_block(db, db.get_top_block(), pulse_round);
}

service_nodes::quorum generate_pulse_quorum(
        cryptonote::network_type nettype,
        crypto::public_key const& block_leader,
        hf hf_version,
        std::vector<pubkey_and_sninfo> const& active_snode_list,
        std::vector<crypto::hash> const& pulse_entropy,
        uint8_t pulse_round) {
    service_nodes::quorum result = {};
    if (active_snode_list.size() < pulse_min_service_nodes(nettype)) {
        log::debug(
                logcat,
                "Insufficient active Service Nodes for Pulse: {}",
                active_snode_list.size());
        return result;
    }

    if (pulse_entropy.size() != PULSE_QUORUM_SIZE) {
        log::debug(logcat, "Blockchain has insufficient blocks to generate Pulse data");
        return result;
    }

    std::vector<pubkey_and_sninfo const*> pulse_candidates;
    pulse_candidates.reserve(active_snode_list.size());
    for (auto& node : active_snode_list) {
        if (node.first != block_leader || pulse_round > 0)
            pulse_candidates.push_back(&node);
    }

    // NOTE: Sort ascending in height i.e. sort preferring the longest time since the validator was
    // in a Pulse quorum.
    std::sort(
            pulse_candidates.begin(),
            pulse_candidates.end(),
            [](pubkey_and_sninfo const* a, pubkey_and_sninfo const* b) {
                if (a->second->pulse_sorter == b->second->pulse_sorter)
                    return memcmp(reinterpret_cast<const void*>(&a->first),
                                  reinterpret_cast<const void*>(&b->first),
                                  sizeof(a->first)) < 0;
                return a->second->pulse_sorter < b->second->pulse_sorter;
            });

    crypto::public_key block_producer;
    if (pulse_round == 0) {
        block_producer = block_leader;
    } else {
        std::mt19937_64 rng = quorum_rng(hf_version, pulse_entropy[0], quorum_type::pulse);
        size_t producer_index = tools::uniform_distribution_portable(rng, pulse_candidates.size());
        block_producer = pulse_candidates[producer_index]->first;
        pulse_candidates.erase(pulse_candidates.begin() + producer_index);
    }

    // NOTE: Order the candidates so the first half nodes in the list is the validators for this
    // round.
    // - Divide the list in half, select validators from the first half of the list.
    // - Swap the chosen validator into the moving first half of the list.
    auto running_it = pulse_candidates.begin();
    size_t const partition_index = (pulse_candidates.size() - 1) / 2;
    if (partition_index == 0) {
        running_it += service_nodes::PULSE_QUORUM_NUM_VALIDATORS;
    } else {
        for (size_t i = 0; i < service_nodes::PULSE_QUORUM_NUM_VALIDATORS; i++) {
            crypto::hash const& entropy = pulse_entropy[i + 1];
            std::mt19937_64 rng = quorum_rng(hf_version, entropy, quorum_type::pulse);
            size_t validators_available = std::distance(running_it, pulse_candidates.end());
            size_t swap_index = tools::uniform_distribution_portable(
                    rng, std::min(partition_index, validators_available));
            std::swap(*running_it, *(running_it + swap_index));
            running_it++;
        }
    }

    result.workers.push_back(block_producer);
    result.validators.reserve(PULSE_QUORUM_NUM_VALIDATORS);
    for (auto it = pulse_candidates.begin(); it != running_it; it++) {
        crypto::public_key const& node_key = (*it)->first;
        result.validators.push_back(node_key);
    }
    return result;
}

static void generate_other_quorums(
        service_node_list::state_t& state,
        std::vector<pubkey_and_sninfo> const& active_snode_list,
        cryptonote::network_type nettype,
        hf hf_version) {
    assert(state.block_hash);

    // The two quorums here have different selection criteria: the entire checkpoint quorum and the
    // state change *validators* want only active service nodes, but the state change *workers*
    // (i.e. the nodes to be tested) also include decommissioned service nodes.  (Prior to v12 there
    // are no decommissioned nodes, so this distinction is irrelevant for network concensus).
    std::vector<pubkey_and_sninfo> decomm_snode_list;
    if (hf_version >= hf::hf12_checkpointing)
        decomm_snode_list = state.decommissioned_service_nodes_infos();

    quorum_type const max_quorum_type = max_quorum_type_for_hf(hf_version);
    for (int type_int = 0; type_int <= (int)max_quorum_type; type_int++) {
        auto type = static_cast<quorum_type>(type_int);
        auto quorum = std::make_shared<service_nodes::quorum>();
        std::vector<size_t> pub_keys_indexes;

        size_t num_validators = 0;
        size_t num_workers = 0;
        switch (type) {
            case quorum_type::obligations: {
                size_t total_nodes = active_snode_list.size() + decomm_snode_list.size();
                num_validators = std::min(active_snode_list.size(), STATE_CHANGE_QUORUM_SIZE);
                pub_keys_indexes = generate_shuffled_service_node_index_list(
                        hf_version,
                        total_nodes,
                        state.block_hash,
                        type,
                        num_validators,
                        active_snode_list.size());
                state.quorums.obligations = quorum;
                size_t num_remaining_nodes = total_nodes - num_validators;
                num_workers = std::min(
                        num_remaining_nodes,
                        std::max(
                                STATE_CHANGE_MIN_NODES_TO_TEST,
                                num_remaining_nodes / STATE_CHANGE_NTH_OF_THE_NETWORK_TO_TEST));
            } break;

            case quorum_type::checkpointing: {
                // Checkpoint quorums only exist every CHECKPOINT_INTERVAL blocks, but the height
                // that gets used to generate the quorum (i.e. the `height` variable here) is
                // actually `H - REORG_SAFETY_BUFFER_BLOCKS_POST_HF12`, where H is divisible by
                // CHECKPOINT_INTERVAL, but REORG_SAFETY_BUFFER_BLOCKS_POST_HF12 is not (it equals
                // 11).  Hence the addition here to "undo" the lag before checking to see if we're
                // on an interval multiple:
                if ((state.height + REORG_SAFETY_BUFFER_BLOCKS_POST_HF12) % CHECKPOINT_INTERVAL !=
                    0)
                    continue;  // Not on an interval multiple: no checkpointing quorum is defined.

                size_t total_nodes = active_snode_list.size();

                // TODO(oxen): Soft fork, remove when testnet gets reset
                if (nettype == cryptonote::network_type::TESTNET && state.height < 85357)
                    total_nodes = active_snode_list.size() + decomm_snode_list.size();

                if (total_nodes >= CHECKPOINT_QUORUM_SIZE) {
                    pub_keys_indexes = generate_shuffled_service_node_index_list(
                            hf_version, total_nodes, state.block_hash, type);
                    num_validators = std::min(pub_keys_indexes.size(), CHECKPOINT_QUORUM_SIZE);
                }
                state.quorums.checkpointing = quorum;
            } break;

            case quorum_type::blink: {
                if (state.height % BLINK_QUORUM_INTERVAL != 0)
                    continue;

                // Further filter the active SN list for the blink quorum to only include SNs that
                // are not scheduled to finish unlocking between the quorum height and a few blocks
                // after the associated blink height.
                pub_keys_indexes.reserve(active_snode_list.size());
                uint64_t const active_until = state.height + BLINK_EXPIRY_BUFFER;
                for (size_t index = 0; index < active_snode_list.size(); index++) {
                    pubkey_and_sninfo const& entry = active_snode_list[index];
                    uint64_t requested_unlock_height = entry.second->requested_unlock_height;
                    if (requested_unlock_height == KEY_IMAGE_AWAITING_UNLOCK_HEIGHT ||
                        requested_unlock_height > active_until)
                        pub_keys_indexes.push_back(index);
                }

                if (pub_keys_indexes.size() >= BLINK_MIN_VOTES) {
                    std::mt19937_64 rng = quorum_rng(hf_version, state.block_hash, type);
                    tools::shuffle_portable(pub_keys_indexes.begin(), pub_keys_indexes.end(), rng);
                    num_validators =
                            std::min<size_t>(pub_keys_indexes.size(), BLINK_SUBQUORUM_SIZE);
                }
                // Otherwise leave empty to signal that there aren't enough SNs to form a usable
                // quorum (to distinguish it from an invalid height, which gets left as a nullptr)
                state.quorums.blink = quorum;

            } break;

            // NOTE: NOP. Pulse quorums are generated pre-Service Node List changes for the block
            case quorum_type::pulse: continue;
            default:
                log::error(logcat, "Unhandled quorum type enum with value: {}", type_int);
                continue;
        }

        quorum->validators.reserve(num_validators);
        quorum->workers.reserve(num_workers);

        size_t i = 0;
        for (; i < num_validators; i++) {
            quorum->validators.push_back(active_snode_list[pub_keys_indexes[i]].first);
        }

        for (; i < num_validators + num_workers; i++) {
            size_t j = pub_keys_indexes[i];
            if (j < active_snode_list.size())
                quorum->workers.push_back(active_snode_list[j].first);
            else
                quorum->workers.push_back(decomm_snode_list[j - active_snode_list.size()].first);
        }
    }
}

void service_node_list::state_t::update_from_block(
        cryptonote::BlockchainDB const& db,
        cryptonote::network_type nettype,
        state_set const& state_history,
        state_set const& state_archive,
        std::unordered_map<crypto::hash, state_t> const& alt_states,
        const cryptonote::block& block,
        const std::vector<cryptonote::transaction>& txs,
        const service_node_keys* my_keys) {
    ++height;
    bool need_swarm_update = false;
    uint64_t block_height = cryptonote::get_block_height(block);
    assert(height == block_height);
    quorums = {};
    block_hash = cryptonote::get_block_hash(block);
    auto hf_version = block.major_version;

    //
    // Generate Pulse Quorum before any SN changes are applied to the list because,
    // the Leader and Validators for this block generated Pulse Data before any
    // TX's included in the block were applied
    //   i.e. before any deregistrations, registrations, decommissions, recommissions.
    //
    crypto::public_key winner_pubkey =
            cryptonote::get_service_node_winner_from_tx_extra(block.miner_tx.extra);
    if (hf_version >= hf::hf16_pulse) {
        std::vector<crypto::hash> entropy =
                get_pulse_entropy_for_next_block(db, block.prev_id, block.pulse.round);
        quorum pulse_quorum = generate_pulse_quorum(
                nettype,
                winner_pubkey,
                hf_version,
                active_service_nodes_infos(),
                entropy,
                block.pulse.round);
        if (verify_pulse_quorum_sizes(pulse_quorum)) {
            // NOTE: Send candidate to the back of the list
            for (size_t quorum_index = 0; quorum_index < pulse_quorum.validators.size();
                 quorum_index++) {
                crypto::public_key const& key = pulse_quorum.validators[quorum_index];
                auto& info_ptr = service_nodes_infos[key];
                service_node_info& new_info = duplicate_info(info_ptr);
                new_info.pulse_sorter.last_height_validating_in_quorum = height;
                new_info.pulse_sorter.quorum_index = quorum_index;
            }

            quorums.pulse = std::make_shared<service_nodes::quorum>(std::move(pulse_quorum));
        }
    }

    //
    // Remove expired blacklisted key images
    //
    if (hf_version >= hf::hf11_infinite_staking) {
        for (auto entry = key_image_blacklist.begin(); entry != key_image_blacklist.end();) {
            if (block_height >= entry->unlock_height)
                entry = key_image_blacklist.erase(entry);
            else
                entry++;
        }
    }

    //
    // Expire Nodes
    //
    for (const crypto::public_key& pubkey :
         get_expired_nodes(db, nettype, block.major_version, block_height)) {
        auto i = service_nodes_infos.find(pubkey);
        if (i != service_nodes_infos.end()) {
            if (my_keys && my_keys->pub == pubkey)
                log::info(
                        logcat,
                        fg(fmt::terminal_color::green),
                        "Service node expired (yours): {} at block height: {}",
                        pubkey,
                        block_height);
            else
                log::info(
                        logcat,
                        "Service node expired: {} at block height: {}",
                        pubkey,
                        block_height);

            need_swarm_update += i->second->is_active();
            service_nodes_infos.erase(i);
        }
    }

    //
    // Advance the list to the next candidate for a reward
    //
    {
        auto it = service_nodes_infos.find(winner_pubkey);
        if (it != service_nodes_infos.end()) {
            // set the winner as though it was re-registering at transaction index=UINT32_MAX for
            // this block
            auto& info = duplicate_info(it->second);
            info.last_reward_block_height = block_height;
            info.last_reward_transaction_index = UINT32_MAX;
        }
    }

    //
    // Process TXs in the Block
    //
    cryptonote::txtype max_tx_type = cryptonote::transaction::get_max_type_for_hf(hf_version);
    cryptonote::txtype staking_tx_type = (max_tx_type < cryptonote::txtype::stake)
                                               ? cryptonote::txtype::standard
                                               : cryptonote::txtype::stake;
    for (uint32_t index = 0; index < txs.size(); ++index) {
        const cryptonote::transaction& tx = txs[index];
        if (tx.type == staking_tx_type) {
            process_registration_tx(nettype, block, tx, index, my_keys);
            need_swarm_update += process_contribution_tx(nettype, block, tx, index);
        } else if (tx.type == cryptonote::txtype::state_change) {
            need_swarm_update += process_state_change_tx(
                    state_history, state_archive, alt_states, nettype, block, tx, my_keys);
        } else if (tx.type == cryptonote::txtype::key_image_unlock) {
            process_key_image_unlock_tx(nettype, hf_version, block_height, tx);
        }
    }

    // Filtered pubkey-sorted vector of service nodes that are active (fully funded and *not*
    // decommissioned).
    std::vector<pubkey_and_sninfo> active_snode_list = sort_and_filter(
            service_nodes_infos, [](const service_node_info& info) { return info.is_active(); });

    if (need_swarm_update) {
        crypto::hash const block_hash = cryptonote::get_block_hash(block);
        uint64_t seed = 0;
        std::memcpy(&seed, block_hash.data(), sizeof(seed));

        /// Gather existing swarms from infos
        swarm_snode_map_t existing_swarms;
        for (const auto& key_info : active_snode_list)
            existing_swarms[key_info.second->swarm_id].push_back(key_info.first);

        calc_swarm_changes(existing_swarms, seed);

        /// Apply changes
        for (const auto& [swarm_id, snodes] : existing_swarms) {
            for (const auto& snode : snodes) {
                auto& sn_info_ptr = service_nodes_infos.at(snode);
                if (sn_info_ptr->swarm_id == swarm_id)
                    continue;  /// nothing changed for this snode
                duplicate_info(sn_info_ptr).swarm_id = swarm_id;
            }
        }
    }

    generate_other_quorums(*this, active_snode_list, nettype, hf_version);
}

void service_node_list::process_block(
        const cryptonote::block& block, const std::vector<cryptonote::transaction>& txs) {
    uint64_t block_height = cryptonote::get_block_height(block);
    auto hf_version = block.major_version;

    if (hf_version < hf::hf9_service_nodes)
        return;

    // Cull old history
    uint64_t cull_height = short_term_state_cull_height(hf_version, block_height);
    {
        auto end_it = m_transient.state_history.upper_bound(cull_height);
        for (auto it = m_transient.state_history.begin(); it != end_it; it++) {
            if (m_store_quorum_history)
                m_transient.old_quorum_states.emplace_back(it->height, it->quorums);

            uint64_t next_long_term_state = ((it->height / STORE_LONG_TERM_STATE_INTERVAL) + 1) *
                                            STORE_LONG_TERM_STATE_INTERVAL;
            uint64_t dist_to_next_long_term_state = next_long_term_state - it->height;
            bool need_quorum_for_future_states =
                    (dist_to_next_long_term_state <=
                     VOTE_LIFETIME + VOTE_OR_TX_VERIFY_HEIGHT_BUFFER);
            if ((it->height % STORE_LONG_TERM_STATE_INTERVAL) == 0 ||
                need_quorum_for_future_states) {
                m_transient.state_added_to_archive = true;
                if (need_quorum_for_future_states)  // Preserve just quorum
                {
                    state_t& state = const_cast<state_t&>(
                            *it);  // safe: set order only depends on state_t.height
                    state.service_nodes_infos = {};
                    state.key_image_blacklist = {};
                    state.only_loaded_quorums = true;
                }
                m_transient.state_archive.emplace_hint(
                        m_transient.state_archive.end(), std::move(*it));
            }
        }
        m_transient.state_history.erase(m_transient.state_history.begin(), end_it);

        if (m_transient.old_quorum_states.size() > m_store_quorum_history)
            m_transient.old_quorum_states.erase(
                    m_transient.old_quorum_states.begin(),
                    m_transient.old_quorum_states.begin() +
                            (m_transient.old_quorum_states.size() - m_store_quorum_history));
    }

    // Cull alt state history
    for (auto it = m_transient.alt_state.begin(); it != m_transient.alt_state.end();) {
        state_t const& alt_state = it->second;
        if (alt_state.height < cull_height)
            it = m_transient.alt_state.erase(it);
        else
            it++;
    }

    cryptonote::network_type nettype = m_blockchain.nettype();
    m_transient.state_history.insert(m_transient.state_history.end(), m_state);
    m_state.update_from_block(
            m_blockchain.get_db(),
            nettype,
            m_transient.state_history,
            m_transient.state_archive,
            {},
            block,
            txs,
            m_service_node_keys);
}

void service_node_list::blockchain_detached(uint64_t height) {
    std::lock_guard lock(m_sn_mutex);

    uint64_t revert_to_height = height - 1;
    bool reinitialise = false;
    bool using_archive = false;
    {
        auto it = m_transient.state_history.find(
                revert_to_height);  // Try finding detached height directly
        reinitialise = (it == m_transient.state_history.end() || it->only_loaded_quorums);
        if (!reinitialise)
            m_transient.state_history.erase(std::next(it), m_transient.state_history.end());
    }

    // TODO(oxen): We should loop through the prev 10k heights for robustness, but avoid for v4.0.5.
    // Already enough changes going in
    if (reinitialise)  // Try finding the next closest old state at 10k intervals
    {
        uint64_t prev_interval =
                revert_to_height - (revert_to_height % STORE_LONG_TERM_STATE_INTERVAL);
        auto it = m_transient.state_archive.find(prev_interval);
        reinitialise = (it == m_transient.state_archive.end() || it->only_loaded_quorums);
        if (!reinitialise) {
            m_transient.state_history.clear();
            m_transient.state_archive.erase(std::next(it), m_transient.state_archive.end());
            using_archive = true;
        }
    }

    if (reinitialise) {
        m_transient.state_history.clear();
        m_transient.state_archive.clear();
        init();
        return;
    }

    auto& history = (using_archive) ? m_transient.state_archive : m_transient.state_history;
    auto it = std::prev(history.end());
    m_state = std::move(*it);
    history.erase(it);
}

std::vector<crypto::public_key> service_node_list::state_t::get_expired_nodes(
        cryptonote::BlockchainDB const& db,
        cryptonote::network_type nettype,
        hf hf_version,
        uint64_t block_height) const {
    std::vector<crypto::public_key> expired_nodes;
    uint64_t const lock_blocks = staking_num_lock_blocks(nettype);

    // TODO(oxen): This should really use the registration height instead of getting the block and
    // expiring nodes. But there's something subtly off when using registration height causing
    // syncing problems.
    if (hf_version == hf::hf9_service_nodes) {
        if (block_height <= lock_blocks)
            return expired_nodes;

        const uint64_t expired_nodes_block_height = block_height - lock_blocks;
        cryptonote::block block = {};
        try {
            block = db.get_block_from_height(expired_nodes_block_height);
        } catch (std::exception const& e) {
            log::error(
                    logcat,
                    "Failed to get historical block to find expired nodes in v9: {}",
                    e.what());
            return expired_nodes;
        }

        if (block.major_version < hf::hf9_service_nodes)
            return expired_nodes;

        for (crypto::hash const& hash : block.tx_hashes) {
            cryptonote::transaction tx;
            if (!db.get_tx(hash, tx)) {
                log::error(
                        logcat, "Failed to get historical tx to find expired service nodes in v9");
                continue;
            }

            uint32_t index = 0;
            crypto::public_key key;
            service_node_info info = {};
            if (is_registration_tx(
                        nettype,
                        hf::hf9_service_nodes,
                        tx,
                        block.timestamp,
                        expired_nodes_block_height,
                        index,
                        key,
                        info))
                expired_nodes.push_back(key);
            index++;
        }

    } else {
        for (auto it = service_nodes_infos.begin(); it != service_nodes_infos.end(); it++) {
            crypto::public_key const& snode_key = it->first;
            const service_node_info& info = *it->second;
            if (info.registration_hf_version >= hf::hf11_infinite_staking) {
                if (info.requested_unlock_height != KEY_IMAGE_AWAITING_UNLOCK_HEIGHT &&
                    block_height > info.requested_unlock_height)
                    expired_nodes.push_back(snode_key);
            } else  // Version 10 Bulletproofs
            {
                /// Note: this code exhibits a subtle unintended behaviour: a snode that
                /// registered in hardfork 9 and was scheduled for deregistration in hardfork 10
                /// will have its life is slightly prolonged by the "grace period", although it
                /// might look like we use the registration height to determine the expiry height.
                uint64_t node_expiry_height =
                        info.registration_height + lock_blocks +
                        cryptonote::old::STAKING_REQUIREMENT_LOCK_BLOCKS_EXCESS;
                if (block_height > node_expiry_height)
                    expired_nodes.push_back(snode_key);
            }
        }
    }

    return expired_nodes;
}

service_nodes::payout service_node_list::state_t::get_block_leader() const {
    crypto::public_key key{};
    service_node_info const* info = nullptr;
    {
        auto oldest_waiting = std::make_tuple(
                std::numeric_limits<uint64_t>::max(),
                std::numeric_limits<uint32_t>::max(),
                crypto::null<crypto::public_key>);
        for (const auto& info_it : service_nodes_infos) {
            const auto& sninfo = *info_it.second;
            if (sninfo.is_active()) {
                auto waiting_since = std::make_tuple(
                        sninfo.last_reward_block_height,
                        sninfo.last_reward_transaction_index,
                        info_it.first);
                if (waiting_since < oldest_waiting) {
                    oldest_waiting = waiting_since;
                    info = &sninfo;
                }
            }
        }
        key = std::get<2>(oldest_waiting);
    }

    if (!key)
        return service_nodes::null_payout;
    return service_node_payout_portions(key, *info);
}

template <typename T>
static constexpr bool within_one(T a, T b) {
    return (a > b ? a - b : b - a) <= T{1};
}

// NOTE: Verify queued service node coinbase or pulse block producer rewards
static void verify_coinbase_tx_output(
        cryptonote::transaction const& miner_tx,
        uint64_t height,
        size_t output_index,
        cryptonote::account_public_address const& receiver,
        uint64_t reward) {
    if (output_index >= miner_tx.vout.size())
        throw std::out_of_range{
                "Output Index: {}, indexes out of bounds in vout array with size: {}"_format(
                        output_index, miner_tx.vout.size())};

    cryptonote::tx_out const& output = miner_tx.vout[output_index];

    // Because FP math is involved in reward calculations (and compounded by CPUs, compilers,
    // expression contraction, and RandomX fiddling with the rounding modes) we can end up with a
    // 1 ULP difference in the reward calculations.
    // TODO(oxen): eliminate all FP math from reward calculations
    if (!within_one(output.amount, reward))
        throw std::runtime_error{
                "Service node reward amount incorrect. Should be {}, is: {}"_format(
                        cryptonote::print_money(reward), cryptonote::print_money(output.amount))};

    if (!std::holds_alternative<cryptonote::txout_to_key>(output.target))
        throw std::runtime_error{"Service node output target type should be txout_to_key"};

    // NOTE: Loki uses the governance key in the one-time ephemeral key
    // derivation for both Pulse Block Producer/Queued Service Node Winner rewards
    crypto::key_derivation derivation{};
    crypto::public_key out_eph_public_key{};
    cryptonote::keypair gov_key = cryptonote::get_deterministic_keypair_from_height(height);

    if (!crypto::generate_key_derivation(receiver.m_view_public_key, gov_key.sec, derivation))
        throw std::runtime_error{"Failed to generate key derivation"};
    if (!crypto::derive_public_key(
                derivation, output_index, receiver.m_spend_public_key, out_eph_public_key))
        throw std::runtime_error{"Failed derive public key"};

    if (var::get<cryptonote::txout_to_key>(output.target).key != out_eph_public_key)
        throw std::runtime_error{
                "Invalid service node reward at output: {}, output key, specifies wrong key"_format(
                        output_index)};
}

void service_node_list::validate_miner_tx(const cryptonote::miner_tx_info& info) const {
    const auto& block = info.block;
    const auto& reward_parts = info.reward_parts;
    const auto& batched_sn_payments = info.batched_sn_payments;
    const auto hf_version = block.major_version;
    if (hf_version < hf::hf9_service_nodes)
        return;

    std::lock_guard lock(m_sn_mutex);
    uint64_t const height = cryptonote::get_block_height(block);
    cryptonote::transaction const& miner_tx = block.miner_tx;

    // NOTE: Basic queued service node list winner checks
    // NOTE(oxen): Service node reward distribution is calculated from the
    // original amount, i.e. 50% of the original base reward goes to service
    // nodes not 50% of the reward after removing the governance component (the
    // adjusted base reward post hardfork 10).
    payout const block_leader = m_state.get_block_leader();
    {
        auto const check_block_leader_pubkey =
                cryptonote::get_service_node_winner_from_tx_extra(miner_tx.extra);
        if (block_leader.key != check_block_leader_pubkey)
            throw std::runtime_error{
                    "Service node reward winner is incorrect! Expected {}, block has {}"_format(
                            block_leader.key, check_block_leader_pubkey)};
    }

    enum struct verify_mode {
        miner,
        pulse_block_leader_is_producer,
        pulse_different_block_producer,
        batched_sn_rewards,
    };

    verify_mode mode = verify_mode::miner;
    crypto::public_key block_producer_key = {};

    //
    // NOTE: Determine if block leader/producer are different or the same.
    //
    if (cryptonote::block_has_pulse_components(block)) {
        std::vector<crypto::hash> entropy = get_pulse_entropy_for_next_block(
                m_blockchain.get_db(), block.prev_id, block.pulse.round);
        quorum pulse_quorum = generate_pulse_quorum(
                m_blockchain.nettype(),
                block_leader.key,
                hf_version,
                m_state.active_service_nodes_infos(),
                entropy,
                block.pulse.round);
        if (!verify_pulse_quorum_sizes(pulse_quorum))
            throw std::runtime_error{
                    "Pulse block received but Pulse has insufficient nodes for quorum, block hash {}, height {}"_format(
                            cryptonote::get_block_hash(block), height)};

        block_producer_key = pulse_quorum.workers[0];
        mode = (block_producer_key == block_leader.key)
                     ? verify_mode::pulse_block_leader_is_producer
                     : verify_mode::pulse_different_block_producer;

        if (block.pulse.round == 0 && (mode == verify_mode::pulse_different_block_producer))
            throw std::runtime_error{
                    "The block producer in pulse round 0 should be the same node as the block leader: {}, actual producer: {}"_format(
                            block_leader.key, block_producer_key)};
    }

    // NOTE: Verify miner tx vout composition
    //
    // Miner Block
    // 1       | Miner
    // Up To 4 | Queued Service Node
    // Up To 1 | Governance
    //
    // Pulse Block
    // Up to 4 | Block Producer (0-3 for Pooled Service Node)
    // Up To 4 | Queued Service Node
    // Up To 1 | Governance
    //
    // NOTE: See cryptonote_tx_utils.cpp construct_miner_tx(...) for payment details.
    //

    std::shared_ptr<const service_node_info> block_producer = nullptr;

    if (block.major_version >= hf::hf19_reward_batching) {
        mode = verify_mode::batched_sn_rewards;
        log::debug(logcat, "Batched miner reward");
    }

    size_t expected_vouts_size;
    switch (mode) {
        case verify_mode::batched_sn_rewards:
            expected_vouts_size = batched_sn_payments.size();
            break;
        case verify_mode::pulse_block_leader_is_producer:
        case verify_mode::pulse_different_block_producer: {
            auto info_it = m_state.service_nodes_infos.find(block_producer_key);
            if (info_it == m_state.service_nodes_infos.end())
                throw std::runtime_error{
                        "The pulse block producer for round {:d} is not current a Service Node: {}"_format(
                                block.pulse.round, block_producer_key)};

            block_producer = info_it->second;
            expected_vouts_size = mode == verify_mode::pulse_different_block_producer &&
                                                  reward_parts.miner_fee > 0
                                        ? block_producer->contributors.size()
                                        : 0;
        } break;
        case verify_mode::miner:
            expected_vouts_size =
                    reward_parts.base_miner + reward_parts.miner_fee >
                                    0  // (HF >= 16) this can be zero, no miner coinbase.
                            ? 1        /* miner */
                            : 0;
            break;
    }

    if (mode != verify_mode::batched_sn_rewards) {
        expected_vouts_size += block_leader.payouts.size();
        bool has_governance_output = cryptonote::height_has_governance_output(
                m_blockchain.nettype(), hf_version, height);
        if (has_governance_output)
            expected_vouts_size++;
    }

    if (miner_tx.vout.size() != expected_vouts_size)
        throw std::runtime_error{
                "Expected {} block, the miner TX specifies a different amount of outputs vs the expected: {}, miner tx outputs: {}"_format(
                        mode == verify_mode::miner                            ? "miner"sv
                        : mode == verify_mode::batched_sn_rewards             ? "batch reward"sv
                        : mode == verify_mode::pulse_block_leader_is_producer ? "pulse"sv
                                                                              : "pulse alt round"sv,
                        expected_vouts_size,
                        miner_tx.vout.size())};

    if (hf_version >= hf::hf16_pulse && reward_parts.base_miner != 0)
        throw std::runtime_error{
                "Miner reward is incorrect expected 0 reward, block specified {}"_format(
                        cryptonote::print_money(reward_parts.base_miner))};

    // NOTE: Verify Coinbase Amounts
    switch (mode) {
        case verify_mode::miner: {
            size_t vout_index = 0 + (reward_parts.base_miner + reward_parts.miner_fee > 0);

            // We don't verify the miner reward amount because it is already implied by the overall
            // sum of outputs check and because when there are truncation errors on other outputs
            // the miner reward ends up with the difference (and so actual miner output amount can
            // be a few atoms larger than base_miner+miner_fee).

            std::vector<uint64_t> split_rewards = cryptonote::distribute_reward_by_portions(
                    block_leader.payouts,
                    reward_parts.service_node_total,
                    hf_version >= hf::hf16_pulse /*distribute_remainder*/);

            for (size_t i = 0; i < block_leader.payouts.size(); i++) {
                const auto& payout = block_leader.payouts[i];
                if (split_rewards[i]) {
                    verify_coinbase_tx_output(
                            miner_tx, height, vout_index, payout.address, split_rewards[i]);
                    vout_index++;
                }
            }
        } break;

        case verify_mode::pulse_block_leader_is_producer: {
            uint64_t total_reward = reward_parts.service_node_total + reward_parts.miner_fee;
            std::vector<uint64_t> split_rewards = cryptonote::distribute_reward_by_portions(
                    block_leader.payouts, total_reward, true /*distribute_remainder*/);
            assert(total_reward > 0);

            size_t vout_index = 0;
            for (size_t i = 0; i < block_leader.payouts.size(); i++) {
                const auto& payout = block_leader.payouts[i];
                if (split_rewards[i]) {
                    verify_coinbase_tx_output(
                            miner_tx, height, vout_index, payout.address, split_rewards[i]);
                    vout_index++;
                }
            }
        } break;

        case verify_mode::pulse_different_block_producer: {
            size_t vout_index = 0;
            {
                payout block_producer_payouts =
                        service_node_payout_portions(block_producer_key, *block_producer);
                std::vector<uint64_t> split_rewards = cryptonote::distribute_reward_by_portions(
                        block_producer_payouts.payouts,
                        reward_parts.miner_fee,
                        true /*distribute_remainder*/);
                for (size_t i = 0; i < block_producer_payouts.payouts.size(); i++) {
                    const auto& payout = block_producer_payouts.payouts[i];
                    if (split_rewards[i]) {
                        verify_coinbase_tx_output(
                                miner_tx, height, vout_index, payout.address, split_rewards[i]);
                        vout_index++;
                    }
                }
            }

            std::vector<uint64_t> split_rewards = cryptonote::distribute_reward_by_portions(
                    block_leader.payouts,
                    reward_parts.service_node_total,
                    true /*distribute_remainder*/);
            for (size_t i = 0; i < block_leader.payouts.size(); i++) {
                const auto& payout = block_leader.payouts[i];
                if (split_rewards[i]) {
                    verify_coinbase_tx_output(
                            miner_tx, height, vout_index, payout.address, split_rewards[i]);
                    vout_index++;
                }
            }
        } break;

        case verify_mode::batched_sn_rewards: {
            // NB: this amount is in milli-atomics, not atomics
            uint64_t total_payout_in_our_db = std::accumulate(
                    batched_sn_payments.begin(),
                    batched_sn_payments.end(),
                    uint64_t{0},
                    [](auto&& a, auto&& b) { return a + b.amount; });

            uint64_t total_payout_in_vouts = 0;
            const auto deterministic_keypair =
                    cryptonote::get_deterministic_keypair_from_height(height);
            for (size_t vout_index = 0; vout_index < block.miner_tx.vout.size(); vout_index++) {
                const auto& vout = block.miner_tx.vout[vout_index];
                const auto& batch_payment = batched_sn_payments[vout_index];

                if (!std::holds_alternative<cryptonote::txout_to_key>(vout.target))
                    throw std::runtime_error{
                            "Service node output target type should be txout_to_key"};

                constexpr uint64_t max_amount =
                        std::numeric_limits<uint64_t>::max() / cryptonote::BATCH_REWARD_FACTOR;
                if (vout.amount > max_amount)
                    throw std::runtime_error{
                            "Batched reward payout invalid: exceeds maximum possible payout size"};

                auto paid_amount = vout.amount * cryptonote::BATCH_REWARD_FACTOR;
                total_payout_in_vouts += paid_amount;
                if (paid_amount != batch_payment.amount)
                    throw std::runtime_error{
                            "Batched reward payout incorrect: expected {}, not {}"_format(
                                    batch_payment.amount, paid_amount)};

                crypto::public_key out_eph_public_key{};
                if (!cryptonote::get_deterministic_output_key(
                            batch_payment.address_info.address,
                            deterministic_keypair,
                            vout_index,
                            out_eph_public_key))
                    throw std::runtime_error{"Failed to generate output one-time public key"};

                const auto& out_to_key = var::get<cryptonote::txout_to_key>(vout.target);
                if (tools::view_guts(out_to_key) != tools::view_guts(out_eph_public_key))
                    throw std::runtime_error{
                            "Output Ephermeral Public Key does not match (payment to wrong "
                            "recipient)"};
            }
            if (total_payout_in_vouts != total_payout_in_our_db)
                throw std::runtime_error{
                        "Total service node reward amount incorrect: expected {}, not {}"_format(
                                total_payout_in_our_db, total_payout_in_vouts)};
        } break;
    }
}

void service_node_list::alt_block_add(const cryptonote::block_add_info& info) {
    // NOTE: The premise is to search the main list and the alternative list for
    // the parent of the block we just received, generate the new Service Node
    // state with this alt-block and verify that the block passes all
    // the necessary checks.

    // On success, this function returns true, signifying the block is valid to
    // store into the alt-chain until it gathers enough blocks to cause
    // a reorganization (more checkpoints/PoW than the main chain).

    auto& block = info.block;
    if (block.major_version < hf::hf9_service_nodes)
        return;

    uint64_t block_height = cryptonote::get_block_height(block);
    state_t const* starting_state = nullptr;
    crypto::hash const block_hash = get_block_hash(block);

    auto it = m_transient.alt_state.find(block_hash);
    if (it != m_transient.alt_state.end())
        return;  // NOTE: Already processed alt-state for this block

    // NOTE: Check if alt block forks off some historical state on the canonical chain
    if (!starting_state) {
        auto it = m_transient.state_history.find(block_height - 1);
        if (it != m_transient.state_history.end())
            if (block.prev_id == it->block_hash)
                starting_state = &(*it);
    }

    // NOTE: Check if alt block forks off some historical alt state on an alt chain
    if (!starting_state) {
        auto it = m_transient.alt_state.find(block.prev_id);
        if (it != m_transient.alt_state.end())
            starting_state = &it->second;
    }

    if (!starting_state)
        throw std::runtime_error{
                "Received alt block but couldn't find parent state in historical state"};

    if (starting_state->block_hash != block.prev_id)
        throw std::runtime_error{
                "Unexpected state_t's hash: {}, does not match the block prev hash: {}"_format(
                        starting_state->block_hash, block.prev_id)};

    // NOTE: Generate the next Service Node list state from this Alt block.
    state_t alt_state = *starting_state;
    alt_state.update_from_block(
            m_blockchain.get_db(),
            m_blockchain.nettype(),
            m_transient.state_history,
            m_transient.state_archive,
            m_transient.alt_state,
            block,
            info.txs,
            m_service_node_keys);
    auto alt_it = m_transient.alt_state.find(block_hash);
    if (alt_it != m_transient.alt_state.end())
        alt_it->second = std::move(alt_state);
    else
        m_transient.alt_state.emplace(block_hash, std::move(alt_state));

    verify_block(block, true /*alt_block*/, info.checkpoint);
}

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

static service_node_list::quorum_for_serialization serialize_quorum_state(
        hf hf_version, uint64_t height, quorum_manager const& quorums) {
    service_node_list::quorum_for_serialization result = {};
    result.height = height;
    if (quorums.obligations)
        result.quorums[static_cast<uint8_t>(quorum_type::obligations)] = *quorums.obligations;
    if (quorums.checkpointing)
        result.quorums[static_cast<uint8_t>(quorum_type::checkpointing)] = *quorums.checkpointing;
    return result;
}

static service_node_list::state_serialized serialize_service_node_state_object(
        hf hf_version,
        service_node_list::state_t const& state,
        bool only_serialize_quorums = false) {
    service_node_list::state_serialized result = {};
    result.version = service_node_list::state_serialized::get_version(hf_version);
    result.height = state.height;
    result.quorums = serialize_quorum_state(hf_version, state.height, state.quorums);
    result.only_stored_quorums = state.only_loaded_quorums || only_serialize_quorums;

    if (only_serialize_quorums)
        return result;

    result.infos.reserve(state.service_nodes_infos.size());
    for (const auto& kv_pair : state.service_nodes_infos)
        result.infos.emplace_back(kv_pair);

    result.key_image_blacklist = state.key_image_blacklist;
    result.block_hash = state.block_hash;
    return result;
}

bool service_node_list::store() {
    if (!m_blockchain.has_db())
        return false;  // Haven't been initialized yet

    auto hf_version = m_blockchain.get_network_version();
    if (hf_version < hf::hf9_service_nodes)
        return true;

    data_for_serialization* data[] = {
            &m_transient.cache_long_term_data, &m_transient.cache_short_term_data};
    auto const serialize_version = data_for_serialization::get_version(hf_version);
    std::lock_guard lock(m_sn_mutex);

    for (data_for_serialization* serialize_entry : data) {
        if (serialize_entry->version != serialize_version)
            m_transient.state_added_to_archive = true;
        serialize_entry->version = serialize_version;
        serialize_entry->clear();
    }

    m_transient.cache_short_term_data.quorum_states.reserve(m_transient.old_quorum_states.size());
    for (const quorums_by_height& entry : m_transient.old_quorum_states)
        m_transient.cache_short_term_data.quorum_states.push_back(
                serialize_quorum_state(hf_version, entry.height, entry.quorums));

    if (m_transient.state_added_to_archive) {
        for (auto const& it : m_transient.state_archive)
            m_transient.cache_long_term_data.states.push_back(
                    serialize_service_node_state_object(hf_version, it));
    }

    // NOTE: A state_t may reference quorums up to (VOTE_LIFETIME
    // + VOTE_OR_TX_VERIFY_HEIGHT_BUFFER) blocks back. So in the
    // (MAX_SHORT_TERM_STATE_HISTORY | 2nd oldest checkpoint) window of states we store, the
    // first (VOTE_LIFETIME + VOTE_OR_TX_VERIFY_HEIGHT_BUFFER) states we only
    // store their quorums, such that the following states have quorum
    // information preceeding it.

    uint64_t const max_short_term_height =
            short_term_state_cull_height(hf_version, (m_state.height - 1)) + VOTE_LIFETIME +
            VOTE_OR_TX_VERIFY_HEIGHT_BUFFER;
    for (auto it = m_transient.state_history.begin();
         it != m_transient.state_history.end() && it->height <= max_short_term_height;
         it++) {
        // TODO(oxen): There are 2 places where we convert a state_t to be a serialized state_t
        // without quorums. We should only do this in one location for clarity.
        m_transient.cache_short_term_data.states.push_back(serialize_service_node_state_object(
                hf_version, *it, it->height < max_short_term_height /*only_serialize_quorums*/));
    }

    m_transient.cache_data_blob.clear();
    if (m_transient.state_added_to_archive) {
        serialization::binary_string_archiver ba;
        try {
            serialization::serialize(ba, m_transient.cache_long_term_data);
        } catch (const std::exception& e) {
            log::error(
                    logcat,
                    "Failed to store service node info: failed to serialize long term data: {}",
                    e.what());
            return false;
        }
        m_transient.cache_data_blob.append(ba.str());
        {
            auto& db = m_blockchain.get_db();
            cryptonote::db_wtxn_guard txn_guard{db};
            db.set_service_node_data(m_transient.cache_data_blob, true /*long_term*/);
        }
    }

    m_transient.cache_data_blob.clear();
    {
        serialization::binary_string_archiver ba;
        try {
            serialization::serialize(ba, m_transient.cache_short_term_data);
        } catch (const std::exception& e) {
            log::error(
                    logcat,
                    "Failed to store service node info: failed to serialize short term data: {}",
                    e.what());
            return false;
        }
        m_transient.cache_data_blob.append(ba.str());
        {
            auto& db = m_blockchain.get_db();
            cryptonote::db_wtxn_guard txn_guard{db};
            db.set_service_node_data(m_transient.cache_data_blob, false /*long_term*/);
        }
    }

    m_transient.state_added_to_archive = false;
    return true;
}

// TODO: remove after HF18, snode revision 1
crypto::hash service_node_list::hash_uptime_proof(
        const cryptonote::NOTIFY_UPTIME_PROOF::request& proof) const {
    size_t buf_size;
    crypto::hash result;

    auto buf = tools::memcpy_le(
            proof.pubkey,
            proof.timestamp,
            proof.public_ip,
            proof.storage_https_port,
            proof.pubkey_ed25519,
            proof.qnet_port,
            proof.storage_omq_port);
    buf_size = buf.size();
    crypto::cn_fast_hash(buf.data(), buf_size, result);
    return result;
}

cryptonote::NOTIFY_UPTIME_PROOF::request service_node_list::generate_uptime_proof(
        uint32_t public_ip,
        uint16_t storage_https_port,
        uint16_t storage_omq_port,
        uint16_t quorumnet_port) const {
    assert(m_service_node_keys);
    const auto& keys = *m_service_node_keys;
    cryptonote::NOTIFY_UPTIME_PROOF::request result = {};
    result.snode_version = OXEN_VERSION;
    result.timestamp = time(nullptr);
    result.pubkey = keys.pub;
    result.public_ip = public_ip;
    result.storage_https_port = storage_https_port;
    result.storage_omq_port = storage_omq_port;
    result.qnet_port = quorumnet_port;
    result.pubkey_ed25519 = keys.pub_ed25519;

    crypto::hash hash = hash_uptime_proof(result);
    crypto::generate_signature(hash, keys.pub, keys.key, result.sig);
    crypto_sign_detached(
            result.sig_ed25519.data(), NULL, hash.data(), hash.size(), keys.key_ed25519.data());
    return result;
}

uptime_proof::Proof service_node_list::generate_uptime_proof(
        uint32_t public_ip,
        uint16_t storage_https_port,
        uint16_t storage_omq_port,
        std::array<uint16_t, 3> ss_version,
        uint16_t quorumnet_port,
        std::array<uint16_t, 3> lokinet_version) const {
    const auto& keys = *m_service_node_keys;
    return uptime_proof::Proof(
            public_ip,
            storage_https_port,
            storage_omq_port,
            ss_version,
            quorumnet_port,
            lokinet_version,
            keys);
}

#ifdef __cpp_lib_erase_if  // # (C++20)
using std::erase_if;
#else
template <typename Container, typename Predicate>
static void erase_if(Container& c, Predicate pred) {
    for (auto it = c.begin(), last = c.end(); it != last;) {
        if (pred(*it))
            it = c.erase(it);
        else
            ++it;
    }
}
#endif

template <typename T>
static bool update_val(T& val, const T& to) {
    if (val != to) {
        val = to;
        return true;
    }
    return false;
}

proof_info::proof_info() : proof(std::make_unique<uptime_proof::Proof>()){};

void proof_info::store(const crypto::public_key& pubkey, cryptonote::Blockchain& blockchain) {
    if (!proof)
        proof = std::unique_ptr<uptime_proof::Proof>(new uptime_proof::Proof());
    std::unique_lock lock{blockchain};
    auto& db = blockchain.get_db();
    db.set_service_node_proof(pubkey, *this);
}

bool proof_info::update(
        uint64_t ts,
        std::unique_ptr<uptime_proof::Proof> new_proof,
        const crypto::x25519_public_key& pk_x2) {
    bool update_db = false;
    if (!proof || *proof != *new_proof) {
        update_db = true;
        proof = std::move(new_proof);
    }
    update_db |= update_val(timestamp, ts);
    effective_timestamp = timestamp;
    pubkey_x25519 = pk_x2;

    // Track an IP change (so that the obligations quorum can penalize for IP changes)
    // We only keep the two most recent because all we really care about is whether it had more than
    // one
    //
    // If we already know about the IP, update its timestamp:
    auto now = std::time(nullptr);
    if (public_ips[0].first && public_ips[0].first == proof->public_ip)
        public_ips[0].second = now;
    else if (public_ips[1].first && public_ips[1].first == proof->public_ip)
        public_ips[1].second = now;
    // Otherwise replace whichever IP has the older timestamp
    else if (public_ips[0].second > public_ips[1].second)
        public_ips[1] = {proof->public_ip, now};
    else
        public_ips[0] = {proof->public_ip, now};

    return update_db;
};

// TODO remove after HF18, snode revision 1
bool proof_info::update(
        uint64_t ts,
        uint32_t ip,
        uint16_t s_https_port,
        uint16_t s_omq_port,
        uint16_t q_port,
        std::array<uint16_t, 3> ver,
        const crypto::ed25519_public_key& pk_ed,
        const crypto::x25519_public_key& pk_x2) {
    bool update_db = false;
    if (!proof)
        proof = std::unique_ptr<uptime_proof::Proof>(new uptime_proof::Proof());
    update_db |= update_val(timestamp, ts);
    update_db |= update_val(proof->public_ip, ip);
    update_db |= update_val(proof->storage_https_port, s_https_port);
    update_db |= update_val(proof->storage_omq_port, s_omq_port);
    update_db |= update_val(proof->qnet_port, q_port);
    update_db |= update_val(proof->version, ver);
    update_db |= update_val(proof->pubkey_ed25519, pk_ed);
    effective_timestamp = timestamp;
    pubkey_x25519 = pk_x2;

    // Track an IP change (so that the obligations quorum can penalize for IP changes)
    // We only keep the two most recent because all we really care about is whether it had more than
    // one
    //
    // If we already know about the IP, update its timestamp:
    auto now = std::time(nullptr);
    if (public_ips[0].first && public_ips[0].first == proof->public_ip)
        public_ips[0].second = now;
    else if (public_ips[1].first && public_ips[1].first == proof->public_ip)
        public_ips[1].second = now;
    // Otherwise replace whichever IP has the older timestamp
    else if (public_ips[0].second > public_ips[1].second)
        public_ips[1] = {proof->public_ip, now};
    else
        public_ips[0] = {proof->public_ip, now};

    return update_db;
};

void proof_info::update_pubkey(const crypto::ed25519_public_key& pk) {
    if (pk == proof->pubkey_ed25519)
        return;
    if (pk && 0 == crypto_sign_ed25519_pk_to_curve25519(pubkey_x25519.data(), pk.data())) {
        proof->pubkey_ed25519 = pk;
    } else {
        log::warning(
                logcat,
                "Failed to derive x25519 pubkey from ed25519 pubkey {}",
                proof->pubkey_ed25519);
        pubkey_x25519.zero();
        proof->pubkey_ed25519.zero();
    }
}

// TODO remove after HF18, snode revision 1
bool service_node_list::handle_uptime_proof(
        cryptonote::NOTIFY_UPTIME_PROOF::request const& proof,
        bool& my_uptime_proof_confirmation,
        crypto::x25519_public_key& x25519_pkey) {
    auto vers = get_network_version_revision(
            m_blockchain.nettype(), m_blockchain.get_current_blockchain_height());
    if (vers >= std::make_pair(hf::hf18, uint8_t{1})) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: Old format (non-bt) proofs are not acceptable "
                "from v18+1 onwards",
                proof.pubkey);
        return false;
    }

    auto& netconf = get_config(m_blockchain.nettype());
    auto now = std::chrono::system_clock::now();

    // Validate proof version, timestamp range,
    auto time_deviation = now - std::chrono::system_clock::from_time_t(proof.timestamp);
    if (time_deviation > netconf.UPTIME_PROOF_TOLERANCE ||
        time_deviation < -netconf.UPTIME_PROOF_TOLERANCE) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: timestamp is too far from now",
                proof.pubkey);
        return false;
    }

    for (auto const& min : MIN_UPTIME_PROOF_VERSIONS)
        if (vers >= min.hardfork_revision && proof.snode_version < min.oxend) {
            log::debug(
                    logcat,
                    "Rejecting uptime proof from {}: v{}+ oxend version is required for v{}.{}+ "
                    "network proofs",
                    proof.pubkey,
                    tools::join(".", min.oxend),
                    static_cast<int>(vers.first),
                    vers.second);
            return false;
        }

    if (!debug_allow_local_ips && !epee::net_utils::is_ip_public(proof.public_ip)) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: public_ip is not actually public",
                proof.pubkey);
        return false;
    }

    //
    // Validate proof signature
    //
    crypto::hash hash = hash_uptime_proof(proof);

    if (!crypto::check_signature(hash, proof.pubkey, proof.sig)) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: signature validation failed",
                proof.pubkey);
        return false;
    }

    crypto::x25519_public_key derived_x25519_pubkey{};
    if (!proof.pubkey_ed25519) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: required ed25519 auxiliary pubkey {} not included "
                "in proof",
                proof.pubkey,
                proof.pubkey_ed25519);
        return false;
    }

    if (0 !=
        crypto_sign_verify_detached(
                proof.sig_ed25519.data(), hash.data(), hash.size(), proof.pubkey_ed25519.data())) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: ed25519 signature validation failed",
                proof.pubkey);
        return false;
    }

    if (0 != crypto_sign_ed25519_pk_to_curve25519(
                     derived_x25519_pubkey.data(), proof.pubkey_ed25519.data()) ||
        !derived_x25519_pubkey) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: invalid ed25519 pubkey included in proof (x25519 "
                "derivation failed)",
                proof.pubkey);
        return false;
    }

    if (proof.qnet_port == 0) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: invalid quorumnet port in uptime proof",
                proof.pubkey);
        return false;
    }

    auto locks = tools::unique_locks(m_blockchain, m_sn_mutex, m_x25519_map_mutex);
    auto it = m_state.service_nodes_infos.find(proof.pubkey);
    if (it == m_state.service_nodes_infos.end()) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: no such service node is currently registered",
                proof.pubkey);
        return false;
    }

    auto& iproof = proofs[proof.pubkey];

    if (now <= std::chrono::system_clock::from_time_t(iproof.timestamp) +
                       std::chrono::seconds{netconf.UPTIME_PROOF_FREQUENCY} / 2) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: already received one uptime proof for this node "
                "recently",
                proof.pubkey);
        return false;
    }

    if (m_service_node_keys && proof.pubkey == m_service_node_keys->pub) {
        my_uptime_proof_confirmation = true;
        log::info(
                logcat,
                "Received uptime-proof confirmation back from network for Service Node (yours): {}",
                proof.pubkey);
    } else {
        my_uptime_proof_confirmation = false;
        log::debug(logcat, "Accepted uptime proof from {}", proof.pubkey);

        if (m_service_node_keys && proof.pubkey_ed25519 == m_service_node_keys->pub_ed25519)
            log::info(
                    logcat,
                    fg(fmt::terminal_color::red),
                    "Uptime proof from SN {} is not us, but is using our ed/x25519 keys; this is "
                    "likely to lead to deregistration of one or both service nodes.",
                    proof.pubkey);
    }

    auto old_x25519 = iproof.pubkey_x25519;
    if (iproof.update(
                std::chrono::system_clock::to_time_t(now),
                proof.public_ip,
                proof.storage_https_port,
                proof.storage_omq_port,
                proof.qnet_port,
                proof.snode_version,
                proof.pubkey_ed25519,
                derived_x25519_pubkey))
        iproof.store(proof.pubkey, m_blockchain);

    if (now - x25519_map_last_pruned >= X25519_MAP_PRUNING_INTERVAL) {
        time_t cutoff = std::chrono::system_clock::to_time_t(now - X25519_MAP_PRUNING_LAG);
        erase_if(x25519_to_pub, [&cutoff](auto& x) { return x.second.second < cutoff; });
        x25519_map_last_pruned = now;
    }

    if (old_x25519 && old_x25519 != derived_x25519_pubkey)
        x25519_to_pub.erase(old_x25519);

    if (derived_x25519_pubkey)
        x25519_to_pub[derived_x25519_pubkey] = {
                proof.pubkey, std::chrono::system_clock::to_time_t(now)};

    if (derived_x25519_pubkey && (old_x25519 != derived_x25519_pubkey))
        x25519_pkey = derived_x25519_pubkey;

    return true;
}

bool service_node_list::handle_btencoded_uptime_proof(
        std::unique_ptr<uptime_proof::Proof> proof,
        bool& my_uptime_proof_confirmation,
        crypto::x25519_public_key& x25519_pkey) {
    auto vers = get_network_version_revision(
            m_blockchain.nettype(), m_blockchain.get_current_blockchain_height());
    auto& netconf = get_config(m_blockchain.nettype());
    auto now = std::chrono::system_clock::now();

    // Validate proof version, timestamp range,
    auto time_deviation = now - std::chrono::system_clock::from_time_t(proof->timestamp);
    if (time_deviation > netconf.UPTIME_PROOF_TOLERANCE ||
        time_deviation < -netconf.UPTIME_PROOF_TOLERANCE) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: timestamp is too far from now",
                proof->pubkey);
        return false;
    }

    for (auto const& min : MIN_UPTIME_PROOF_VERSIONS) {
        if (vers >= min.hardfork_revision &&
            m_blockchain.nettype() != cryptonote::network_type::DEVNET) {
            if (proof->version < min.oxend) {
                log::debug(
                        logcat,
                        "Rejecting uptime proof from {}: v{}+ oxend version is required for "
                        "v{}.{}+ network proofs",
                        proof->pubkey,
                        tools::join(".", min.oxend),
                        static_cast<int>(vers.first),
                        vers.second);
                return false;
            }
            if (proof->lokinet_version < min.lokinet) {
                log::debug(
                        logcat,
                        "Rejecting uptime proof from {}: v{}+ lokinet version is required for "
                        "v{}.{}+ network proofs",
                        proof->pubkey,
                        tools::join(".", min.lokinet),
                        static_cast<int>(vers.first),
                        vers.second);
                return false;
            }
            if (proof->storage_server_version < min.storage_server) {
                log::debug(
                        logcat,
                        "Rejecting uptime proof from {}: v{}+ storage server version is required "
                        "for v{}.{}+ network proofs",
                        proof->pubkey,
                        tools::join(".", min.storage_server),
                        static_cast<int>(vers.first),
                        vers.second);
                return false;
            }
        }
    }

    if (!debug_allow_local_ips && !epee::net_utils::is_ip_public(proof->public_ip)) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: public_ip is not actually public",
                proof->pubkey);
        return false;
    }

    //
    // Validate proof signature
    //
    crypto::hash hash = proof->hash_uptime_proof();

    if (!crypto::check_signature(hash, proof->pubkey, proof->sig)) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: signature validation failed",
                proof->pubkey);
        return false;
    }

    crypto::x25519_public_key derived_x25519_pubkey{};
    if (!proof->pubkey_ed25519) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: required ed25519 auxiliary pubkey {} not included "
                "in proof",
                proof->pubkey,
                proof->pubkey_ed25519);
        return false;
    }

    if (0 != crypto_sign_verify_detached(
                     proof->sig_ed25519.data(),
                     hash.data(),
                     hash.size(),
                     proof->pubkey_ed25519.data())) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: ed25519 signature validation failed",
                proof->pubkey);
        return false;
    }

    if (0 != crypto_sign_ed25519_pk_to_curve25519(
                     derived_x25519_pubkey.data(), proof->pubkey_ed25519.data()) ||
        !derived_x25519_pubkey) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: invalid ed25519 pubkey included in proof (x25519 "
                "derivation failed)",
                proof->pubkey);
        return false;
    }

    if (proof->qnet_port == 0) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: invalid quorumnet port in uptime proof",
                proof->pubkey);
        return false;
    }

    auto locks = tools::unique_locks(m_blockchain, m_sn_mutex, m_x25519_map_mutex);
    auto it = m_state.service_nodes_infos.find(proof->pubkey);
    if (it == m_state.service_nodes_infos.end()) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: no such service node is currently registered",
                proof->pubkey);
        return false;
    }

    auto& iproof = proofs[proof->pubkey];

    if (now <= std::chrono::system_clock::from_time_t(iproof.timestamp) +
                       std::chrono::seconds{netconf.UPTIME_PROOF_FREQUENCY} / 2) {
        log::debug(
                logcat,
                "Rejecting uptime proof from {}: already received one uptime proof for this node "
                "recently",
                proof->pubkey);
        return false;
    }

    if (m_service_node_keys && proof->pubkey == m_service_node_keys->pub) {
        my_uptime_proof_confirmation = true;
        log::info(
                logcat,
                "Received uptime-proof confirmation back from network for Service Node (yours): {}",
                proof->pubkey);
    } else {
        my_uptime_proof_confirmation = false;
        log::debug(logcat, "Accepted uptime proof from {}", proof->pubkey);

        if (m_service_node_keys && proof->pubkey_ed25519 == m_service_node_keys->pub_ed25519)
            log::info(
                    logcat,
                    fg(fmt::terminal_color::red),
                    "Uptime proof from SN {} is not us, but is using our ed/x25519 keys; this is "
                    "likely to lead to deregistration of one or both service nodes.",
                    proof->pubkey);
    }

    auto old_x25519 = iproof.pubkey_x25519;
    if (iproof.update(
                std::chrono::system_clock::to_time_t(now),
                std::move(proof),
                derived_x25519_pubkey)) {
        iproof.store(iproof.proof->pubkey, m_blockchain);
    }

    if (now - x25519_map_last_pruned >= X25519_MAP_PRUNING_INTERVAL) {
        time_t cutoff = std::chrono::system_clock::to_time_t(now - X25519_MAP_PRUNING_LAG);
        erase_if(x25519_to_pub, [&cutoff](const decltype(x25519_to_pub)::value_type& x) {
            return x.second.second < cutoff;
        });
        x25519_map_last_pruned = now;
    }

    if (old_x25519 && old_x25519 != derived_x25519_pubkey)
        x25519_to_pub.erase(old_x25519);

    if (derived_x25519_pubkey)
        x25519_to_pub[derived_x25519_pubkey] = {
                iproof.proof->pubkey, std::chrono::system_clock::to_time_t(now)};

    if (derived_x25519_pubkey && (old_x25519 != derived_x25519_pubkey))
        x25519_pkey = derived_x25519_pubkey;

    return true;
}

void service_node_list::cleanup_proofs() {
    log::debug(logcat, "Cleaning up expired SN proofs");
    auto locks = tools::unique_locks(m_sn_mutex, m_blockchain);
    uint64_t now = std::time(nullptr);
    auto& db = m_blockchain.get_db();
    cryptonote::db_wtxn_guard guard{db};
    for (auto it = proofs.begin(); it != proofs.end();) {
        auto& pubkey = it->first;
        auto& proof = it->second;
        // 6h here because there's no harm in leaving proofs around a bit longer (they aren't big,
        // and we only store one per SN), and it's possible that we could reorg a few blocks and
        // resurrect a service node but don't want to prematurely expire the proof.
        if (!m_state.service_nodes_infos.count(pubkey) && proof.timestamp + 6 * 60 * 60 < now) {
            db.remove_service_node_proof(pubkey);
            it = proofs.erase(it);
        } else
            ++it;
    }
}

crypto::public_key service_node_list::get_pubkey_from_x25519(
        const crypto::x25519_public_key& x25519) const {
    std::shared_lock lock{m_x25519_map_mutex};
    auto it = x25519_to_pub.find(x25519);
    if (it != x25519_to_pub.end())
        return it->second.first;
    return crypto::null<crypto::public_key>;
}

crypto::public_key service_node_list::get_random_pubkey() {
    std::lock_guard lock{m_sn_mutex};
    auto it = tools::select_randomly(
            m_state.service_nodes_infos.begin(), m_state.service_nodes_infos.end());
    if (it != m_state.service_nodes_infos.end()) {
        return it->first;
    } else {
        return m_state.service_nodes_infos.begin()->first;
    }
}

void service_node_list::initialize_x25519_map() {
    auto locks = tools::unique_locks(m_sn_mutex, m_x25519_map_mutex);

    auto now = std::time(nullptr);
    for (const auto& pk_info : m_state.service_nodes_infos) {
        auto it = proofs.find(pk_info.first);
        if (it == proofs.end())
            continue;
        if (const auto& x2_pk = it->second.pubkey_x25519)
            x25519_to_pub.emplace(x2_pk, std::make_pair(pk_info.first, now));
    }
}

std::string service_node_list::remote_lookup(std::string_view xpk) {
    if (xpk.size() != sizeof(crypto::x25519_public_key))
        return "";
    crypto::x25519_public_key x25519_pub;
    std::memcpy(x25519_pub.data(), xpk.data(), xpk.size());

    auto pubkey = get_pubkey_from_x25519(x25519_pub);
    if (!pubkey) {
        log::debug(
                logcat,
                "no connection available: could not find primary pubkey from x25519 pubkey {}",
                x25519_pub);
        return "";
    }

    bool found = false;
    uint32_t ip = 0;
    uint16_t port = 0;
    for_each_service_node_info_and_proof(&pubkey, &pubkey + 1, [&](auto&, auto&, auto& proof) {
        found = true;
        ip = proof.proof->public_ip;
        port = proof.proof->qnet_port;
    });

    if (!found) {
        log::debug(logcat, "no connection available: primary pubkey {} is not registered", pubkey);
        return "";
    }
    if (!(ip && port)) {
        log::debug(
                logcat,
                "no connection available: service node {} has no associated ip and/or port",
                pubkey);
        return "";
    }

    return "tcp://" + epee::string_tools::get_ip_string_from_int32(ip) + ":" + std::to_string(port);
}

void service_node_list::record_checkpoint_participation(
        crypto::public_key const& pubkey, uint64_t height, bool participated) {
    std::lock_guard lock(m_sn_mutex);
    if (m_state.service_nodes_infos.count(pubkey))
        proofs[pubkey].checkpoint_participation.add({height, participated});
}

void service_node_list::record_pulse_participation(
        crypto::public_key const& pubkey, uint64_t height, uint8_t round, bool participated) {
    std::lock_guard lock(m_sn_mutex);
    if (m_state.service_nodes_infos.count(pubkey))
        proofs[pubkey].pulse_participation.add({height, round, participated});
}

void service_node_list::record_timestamp_participation(
        crypto::public_key const& pubkey, bool participated) {
    std::lock_guard lock(m_sn_mutex);
    if (m_state.service_nodes_infos.count(pubkey))
        proofs[pubkey].timestamp_participation.add({participated});
}

void service_node_list::record_timesync_status(crypto::public_key const& pubkey, bool synced) {
    std::lock_guard lock(m_sn_mutex);
    if (m_state.service_nodes_infos.count(pubkey))
        proofs[pubkey].timesync_status.add({synced});
}

std::optional<bool> proof_info::reachable_stats::reachable(
        const std::chrono::steady_clock::time_point& now) const {
    if (last_reachable >= last_unreachable)
        return true;
    if (last_unreachable > now - cryptonote::config::REACHABLE_MAX_FAILURE_VALIDITY)
        return false;
    // Last result was a failure, but it was a while ago, so we don't know for sure that it isn't
    // reachable now:
    return std::nullopt;
}

bool proof_info::reachable_stats::unreachable_for(
        std::chrono::seconds threshold, const std::chrono::steady_clock::time_point& now) const {
    if (auto maybe_reachable = reachable(now);
        !maybe_reachable /*stale*/ || *maybe_reachable /*good*/)
        return false;
    if (first_unreachable > now - threshold)
        return false;  // Unreachable, but for less than the grace time
    return true;
}

bool service_node_list::set_peer_reachable(
        bool storage_server, const crypto::public_key& pubkey, bool reachable) {

    // (See .h for overview description)

    std::lock_guard lock(m_sn_mutex);

    const auto type = storage_server ? "storage server"sv : "lokinet"sv;

    if (!m_state.service_nodes_infos.count(pubkey)) {
        log::debug(
                logcat,
                "Dropping {} reachable report: {} is not a registered SN pubkey",
                type,
                pubkey);
        return false;
    }

    log::debug(
            logcat,
            "Received {}{} report for SN {}",
            type,
            (reachable ? " reachable" : " UNREACHABLE"),
            pubkey);

    const auto now = std::chrono::steady_clock::now();

    auto& reach = storage_server ? proofs[pubkey].ss_reachable : proofs[pubkey].lokinet_reachable;
    if (reachable) {
        reach.last_reachable = now;
        reach.first_unreachable = NEVER;
    } else {
        reach.last_unreachable = now;
        if (reach.first_unreachable == NEVER)
            reach.first_unreachable = now;
    }

    return true;
}
bool service_node_list::set_storage_server_peer_reachable(
        crypto::public_key const& pubkey, bool reachable) {
    return set_peer_reachable(true, pubkey, reachable);
}

bool service_node_list::set_lokinet_peer_reachable(
        crypto::public_key const& pubkey, bool reachable) {
    return set_peer_reachable(false, pubkey, reachable);
}

static quorum_manager quorum_for_serialization_to_quorum_manager(
        service_node_list::quorum_for_serialization const& source) {
    quorum_manager result = {};
    result.obligations = std::make_shared<quorum>(
            source.quorums[static_cast<uint8_t>(quorum_type::obligations)]);

    // Don't load any checkpoints that shouldn't exist (see the comment in generate_quorums as to
    // why the `+BUFFER` term is here).
    if ((source.height + REORG_SAFETY_BUFFER_BLOCKS_POST_HF12) % CHECKPOINT_INTERVAL == 0)
        result.checkpointing = std::make_shared<quorum>(
                source.quorums[static_cast<uint8_t>(quorum_type::checkpointing)]);

    return result;
}

service_node_list::state_t::state_t(service_node_list* snl, state_serialized&& state) :
        height{state.height},
        key_image_blacklist{std::move(state.key_image_blacklist)},
        only_loaded_quorums{state.only_stored_quorums},
        block_hash{state.block_hash},
        sn_list{snl} {
    if (!sn_list)
        throw std::logic_error("Cannot deserialize a state_t without a service_node_list");
    if (state.version == state_serialized::version_t::version_0)
        block_hash = sn_list->m_blockchain.get_block_id_by_height(height);

    for (auto& pubkey_info : state.infos) {
        using version_t = service_node_info::version_t;
        auto& info = const_cast<service_node_info&>(*pubkey_info.info);
        if (info.version < version_t::v1_add_registration_hf_version) {
            info.version = version_t::v1_add_registration_hf_version;
            info.registration_hf_version = sn_list->m_blockchain.get_network_version(
                    pubkey_info.info->registration_height);
        }
        if (info.version < version_t::v4_noproofs) {
            // Nothing to do here (the missing data will be generated in the new proofs db via
            // uptime proofs).
            info.version = version_t::v4_noproofs;
        }
        if (info.version < version_t::v5_pulse_recomm_credit) {
            // If it's an old record then assume it's from before oxen 8, in which case there were
            // only two valid values here: initial for a node that has never been recommissioned, or
            // 0 for a recommission.

            auto was = info.recommission_credit;
            if (info.decommission_count <=
                info.is_decommissioned())  // Has never been decommissioned (or is currently in the
                                           // first decommission), so add initial starting credit
                info.recommission_credit = DECOMMISSION_INITIAL_CREDIT;
            else
                info.recommission_credit = 0;

            info.pulse_sorter.last_height_validating_in_quorum = info.last_reward_block_height;
            info.version = version_t::v5_pulse_recomm_credit;
        }
        if (info.version < version_t::v6_reassign_sort_keys) {
            info.pulse_sorter = {};
            info.version = version_t::v6_reassign_sort_keys;
        }
        if (info.version < version_t::v7_decommission_reason) {
            // Nothing to do here (leave consensus reasons as 0s)
            info.version = version_t::v7_decommission_reason;
        }
        // Make sure we handled any future state version upgrades:
        assert(info.version == tools::enum_top<decltype(info.version)>);
        service_nodes_infos.emplace(std::move(pubkey_info.pubkey), std::move(pubkey_info.info));
    }
    quorums = quorum_for_serialization_to_quorum_manager(state.quorums);
}

bool service_node_list::load(const uint64_t current_height) {
    log::info(logcat, "service_node_list::load()");
    reset(false);
    if (!m_blockchain.has_db()) {
        return false;
    }

    // NOTE: Deserialize long term state history
    uint64_t bytes_loaded = 0;
    auto& db = m_blockchain.get_db();
    cryptonote::db_rtxn_guard txn_guard{db};
    std::string blob;
    if (db.get_service_node_data(blob, true /*long_term*/)) {
        bytes_loaded += blob.size();
        data_for_serialization data_in = {};
        bool success = false;
        try {
            serialization::parse_binary(blob, data_in);
            success = true;
        } catch (...) {
        }

        if (success && data_in.states.size()) {
            // NOTE: Previously the quorum for the next state is derived from the
            // state that's been updated from the next block. This is fixed in
            // version_1.

            // So, copy the quorum from (state.height-1) to (state.height), all
            // states need to have their (height-1) which means we're missing the
            // 10k-th interval and need to generate it based on the last state.

            if (data_in.states[0].version == state_serialized::version_t::version_0) {
                size_t const last_index = data_in.states.size() - 1;
                if ((data_in.states.back().height % STORE_LONG_TERM_STATE_INTERVAL) != 0) {
                    log::warning(
                            logcat,
                            "Last serialised quorum height: {} in archive is unexpectedly not a "
                            "multiple of: {}, regenerating state",
                            data_in.states.back().height,
                            STORE_LONG_TERM_STATE_INTERVAL);
                    return false;
                }

                for (size_t i = data_in.states.size() - 1; i >= 1; i--) {
                    state_serialized& serialized_entry = data_in.states[i];
                    state_serialized& prev_serialized_entry = data_in.states[i - 1];

                    if ((prev_serialized_entry.height % STORE_LONG_TERM_STATE_INTERVAL) == 0) {
                        // NOTE: drop this entry, we have insufficient data to derive
                        // sadly, do this as a one off and if we ever need this data we
                        // need to do a full rescan.
                        continue;
                    }

                    state_t entry{this, std::move(serialized_entry)};
                    entry.height--;
                    entry.quorums = quorum_for_serialization_to_quorum_manager(
                            prev_serialized_entry.quorums);

                    if ((serialized_entry.height % STORE_LONG_TERM_STATE_INTERVAL) == 0) {
                        state_t long_term_state = entry;
                        cryptonote::block const& block =
                                db.get_block_from_height(long_term_state.height + 1);
                        std::vector<cryptonote::transaction> txs = db.get_tx_list(block.tx_hashes);
                        long_term_state.update_from_block(
                                db,
                                m_blockchain.nettype(),
                                {} /*state_history*/,
                                {} /*state_archive*/,
                                {} /*alt_states*/,
                                block,
                                txs,
                                nullptr /*my_keys*/);

                        entry.service_nodes_infos = {};
                        entry.key_image_blacklist = {};
                        entry.only_loaded_quorums = true;
                        m_transient.state_archive.emplace_hint(
                                m_transient.state_archive.begin(), std::move(long_term_state));
                    }
                    m_transient.state_archive.emplace_hint(
                            m_transient.state_archive.begin(), std::move(entry));
                }
            } else {
                for (state_serialized& entry : data_in.states)
                    m_transient.state_archive.emplace_hint(
                            m_transient.state_archive.end(), this, std::move(entry));
            }
        }
    }

    // NOTE: Deserialize short term state history
    if (!db.get_service_node_data(blob, false))
        return false;

    bytes_loaded += blob.size();
    data_for_serialization data_in = {};
    try {
        serialization::parse_binary(blob, data_in);
    } catch (const std::exception& e) {
        log::error(logcat, "Failed to parse service node data from blob: {}", e.what());
        return false;
    }

    if (data_in.states.empty())
        return false;

    {
        const uint64_t hist_state_from_height = current_height - m_store_quorum_history;
        uint64_t last_loaded_height = 0;
        for (auto& states : data_in.quorum_states) {
            if (states.height < hist_state_from_height)
                continue;

            quorums_by_height entry = {};
            entry.height = states.height;
            entry.quorums = quorum_for_serialization_to_quorum_manager(states);

            if (states.height <= last_loaded_height) {
                log::warning(
                        logcat,
                        "Serialised quorums is not stored in ascending order by height in DB, "
                        "failed to load from DB");
                return false;
            }
            last_loaded_height = states.height;
            m_transient.old_quorum_states.push_back(entry);
        }
    }

    {
        assert(data_in.states.size() > 0);
        size_t const last_index = data_in.states.size() - 1;
        if (data_in.states[last_index].only_stored_quorums) {
            log::warning(logcat, "Unexpected last serialized state only has quorums loaded");
            return false;
        }

        if (data_in.states[0].version == state_serialized::version_t::version_0) {
            for (size_t i = last_index; i >= 1; i--) {
                state_serialized& serialized_entry = data_in.states[i];
                state_serialized& prev_serialized_entry = data_in.states[i - 1];
                state_t entry{this, std::move(serialized_entry)};
                entry.quorums =
                        quorum_for_serialization_to_quorum_manager(prev_serialized_entry.quorums);
                entry.height--;
                if (i == last_index)
                    m_state = std::move(entry);
                else
                    m_transient.state_archive.emplace_hint(
                            m_transient.state_archive.end(), std::move(entry));
            }
        } else {
            size_t const last_index = data_in.states.size() - 1;
            for (size_t i = 0; i < last_index; i++) {
                state_serialized& entry = data_in.states[i];
                if (!entry.block_hash)
                    entry.block_hash = m_blockchain.get_block_id_by_height(entry.height);
                m_transient.state_history.emplace_hint(
                        m_transient.state_history.end(), this, std::move(entry));
            }

            m_state = {this, std::move(data_in.states[last_index])};
        }
    }

    // NOTE: Load uptime proof data
    proofs = db.get_all_service_node_proofs();
    if (m_service_node_keys) {
        // Reset our own proof timestamp to zero so that we aggressively try to resend proofs on
        // startup (in case we are restarting because the last proof that we think went out didn't
        // actually make it to the network).
        auto& mine = proofs[m_service_node_keys->pub];
        mine.timestamp = mine.effective_timestamp = 0;
    }

    initialize_x25519_map();

    log::info(logcat, "Service node data loaded successfully, height: {}", m_state.height);
    log::info(
            logcat,
            "{} nodes and {} recent states loaded, {} historical states loaded, ({})",
            m_state.service_nodes_infos.size(),
            m_transient.state_history.size(),
            m_transient.state_archive.size(),
            tools::get_human_readable_bytes(bytes_loaded));

    log::info(logcat, "service_node_list::load() returning success");
    return true;
}

void service_node_list::reset(bool delete_db_entry) {
    m_transient = {};
    m_state = state_t{this};

    if (m_blockchain.has_db() && delete_db_entry) {
        cryptonote::db_wtxn_guard txn_guard{m_blockchain.get_db()};
        m_blockchain.get_db().clear_service_node_data();
    }

    m_state.height =
            hard_fork_begins(m_blockchain.nettype(), hf::hf9_service_nodes).value_or(1) - 1;
}

size_t service_node_info::total_num_locked_contributions() const {
    size_t result = 0;
    for (service_node_info::contributor_t const& contributor : this->contributors)
        result += contributor.locked_contributions.size();
    return result;
}

// Handles the deprecated, pre-HF19 registration parsing where values are portions rather than
// amounts.
// TODO: this can be deleted immediately after HF19, because this code is only used to process new
// registration commands (and after the HF, all registration commands are HF19+ registrations with
// raw amounts rather than portions).
void convert_registration_portions_hf18(
        registration_details& result,
        const std::vector<std::string>& args,
        uint64_t staking_requirement,
        std::vector<std::pair<cryptonote::address_parse_info, uint64_t>>& addr_to_portions,
        hf hf_version) {
    //
    // FIXME(doyle): FIXME(oxen) !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    // This is temporary code to redistribute the insufficient portion dust
    // amounts between contributors. It should be removed in HF12.
    //
    std::array<uint64_t, oxen::MAX_CONTRIBUTORS_V1> excess_portions;
    std::array<uint64_t, oxen::MAX_CONTRIBUTORS_V1> min_contributions;
    {
        // NOTE: Calculate excess portions from each contributor
        uint64_t oxen_reserved = 0;
        for (size_t index = 0; index < addr_to_portions.size(); ++index) {
            const auto& [addr, portion] = addr_to_portions[index];
            uint64_t min_contribution_portions =
                    service_nodes::get_min_node_contribution_in_portions(
                            hf_version, staking_requirement, oxen_reserved, index);
            uint64_t oxen_amount = service_nodes::portions_to_amount(staking_requirement, portion);
            oxen_reserved += oxen_amount;

            uint64_t excess = 0;
            if (portion > min_contribution_portions)
                excess = portion - min_contribution_portions;

            min_contributions[index] = min_contribution_portions;
            excess_portions[index] = excess;
        }
    }

    uint64_t portions_left = cryptonote::old::STAKING_PORTIONS;
    uint64_t total_reserved = 0;
    for (size_t i = 0; i < addr_to_portions.size(); ++i) {
        auto& [addr, portion] = addr_to_portions[i];
        uint64_t min_portions = get_min_node_contribution_in_portions(
                hf_version, staking_requirement, total_reserved, i);

        uint64_t portions_to_steal = 0;
        if (portion < min_portions) {
            // NOTE: Steal dust portions from other contributor if we fall below
            // the minimum by a dust amount.
            uint64_t needed = min_portions - portion;
            const uint64_t FUDGE_FACTOR = 10;
            const uint64_t DUST_UNIT = cryptonote::old::STAKING_PORTIONS / staking_requirement;
            const uint64_t DUST = DUST_UNIT * FUDGE_FACTOR;
            if (needed > DUST)
                continue;

            for (size_t sub_index = 0; sub_index < addr_to_portions.size(); sub_index++) {
                if (i == sub_index)
                    continue;
                uint64_t& contributor_excess = excess_portions[sub_index];
                if (contributor_excess > 0) {
                    portions_to_steal = std::min(needed, contributor_excess);
                    portion += portions_to_steal;
                    contributor_excess -= portions_to_steal;
                    needed -= portions_to_steal;
                    addr_to_portions[sub_index].second -= portions_to_steal;

                    if (needed == 0)
                        break;
                }
            }

            // NOTE: Operator is sending in the minimum amount and it falls below
            // the minimum by dust, just increase the portions so it passes
            if (needed > 0 && addr_to_portions.size() < oxen::MAX_CONTRIBUTORS_V1)
                portion += needed;
        }

        if (portion < min_portions || portion - portions_to_steal > portions_left)
            throw invalid_registration{
                    tr("Invalid amount for contributor: ") + args[i] +
                    tr(", with portion amount: ") + args[i + 1] +
                    tr(". The contributors must each have at least 25%, except for the last "
                       "contributor which may have the remaining amount")};

        if (min_portions == UINT64_MAX)
            throw invalid_registration{
                    tr("Too many contributors specified, you can only split a node with up to: ") +
                    std::to_string(oxen::MAX_CONTRIBUTORS_V1) + tr(" people.")};

        portions_left -= portion;
        portions_left += portions_to_steal;
        result.reserved.emplace_back(addr.address, portion);
        total_reserved += service_nodes::portions_to_amount(portion, staking_requirement);
    }
}

registration_details convert_registration_args(
        cryptonote::network_type nettype,
        cryptonote::hf hf_version,
        const std::vector<std::string>& args,
        uint64_t staking_requirement) {
    registration_details result{};
    if (args.size() % 2 == 0 || args.size() < 3)
        throw invalid_registration{
                tr("Usage: <fee-basis-points> <address> <amount> [<address> <amount> [...]]]")};

    const size_t max_contributors = hf_version >= hf::hf19_reward_batching
                                          ? oxen::MAX_CONTRIBUTORS_HF19
                                          : oxen::MAX_CONTRIBUTORS_V1;
    if (args.size() > 1 + 2 * max_contributors)
        throw invalid_registration{
                tr("Exceeds the maximum number of contributors") + " ("s +
                std::to_string(max_contributors) + ")"};

    const uint64_t max_fee = hf_version >= hf::hf19_reward_batching
                                   ? cryptonote::STAKING_FEE_BASIS
                                   : cryptonote::old::STAKING_PORTIONS;
    if (!tools::parse_int(args[0], result.fee) || result.fee > max_fee)
        throw invalid_registration{
                tr("Invalid operator fee: ") + args[0] + tr(". Must be between 0 and ") +
                std::to_string(max_fee)};

    std::vector<std::pair<cryptonote::address_parse_info, uint64_t>> addr_to_amounts;
    constexpr size_t OPERATOR_ARG_INDEX = 1;
    for (size_t i = OPERATOR_ARG_INDEX, num_contributions = 0; i < args.size();
         i += 2, ++num_contributions) {
        auto& [info, portion] = addr_to_amounts.emplace_back();
        if (!cryptonote::get_account_address_from_str(info, nettype, args[i]))
            throw invalid_registration{tr("Failed to parse address: ") + args[i]};

        if (info.has_payment_id)
            throw invalid_registration{tr("Can't use a payment id for staking tx")};

        if (info.is_subaddress)
            throw invalid_registration{tr("Can't use a subaddress for staking tx")};

        if (!tools::parse_int(args[i + 1], portion))
            throw invalid_registration{
                    tr("Invalid amount for contributor: ") + args[i] +
                    tr(", with portion amount that could not be converted to a number: ") +
                    args[i + 1]};
    }

    uint64_t now = std::chrono::system_clock::to_time_t(std::chrono::system_clock::now());
    if (hf_version < hf::hf19_reward_batching) {
        result.uses_portions = true;
        result.hf = now;
        convert_registration_portions_hf18(
                result, args, staking_requirement, addr_to_amounts, hf_version);
    } else {
        result.uses_portions = false;
        result.hf = static_cast<uint8_t>(hf_version);
        // For HF19+ we just stick in the registration amounts as-is, then validate the registration
        // to make sure it looks good.
        for (const auto& [addr, amount] : addr_to_amounts)
            result.reserved.emplace_back(addr.address, amount);
    }

    // Will throw if something is invalid:
    validate_registration(hf_version, nettype, staking_requirement, now, result);

    return result;
}

bool make_registration_cmd(
        cryptonote::network_type nettype,
        hf hf_version,
        uint64_t staking_requirement,
        const std::vector<std::string>& args,
        const service_node_keys& keys,
        std::string& cmd,
        bool make_friendly) {

    registration_details reg;
    try {
        reg = convert_registration_args(nettype, hf_version, args, staking_requirement);
    } catch (const invalid_registration& e) {
        log::error(logcat, "{}{}", tr("Could not parse registration arguments: "), e.what());
        return false;
    }

    reg.service_node_pubkey = keys.pub;

    if (reg.uses_portions)
        reg.hf = time(nullptr) +
                 tools::to_seconds(cryptonote::old::STAKING_AUTHORIZATION_EXPIRATION_WINDOW);

    auto hash = get_registration_hash(reg);

    reg.signature = crypto::generate_signature(hash, keys.pub, keys.key);

    cmd.clear();
    if (make_friendly)
        cmd += "{} ({}):\n\n"_format(
                tr("Run this command in the operator's wallet"),
                cryptonote::get_account_address_as_str(nettype, false, reg.reserved[0].first));

    cmd += "register_service_node {} {} {} {}"_format(
            tools::join(" ", args),
            reg.hf,
            tools::type_to_hex(reg.service_node_pubkey),
            tools::type_to_hex(reg.signature));

    return true;
}

bool service_node_info::can_be_voted_on(uint64_t height) const {
    // If the SN expired and was reregistered since the height we'll be voting on it prematurely
    if (!is_fully_funded()) {
        log::debug(logcat, "SN vote at height {} invalid: not fully funded", height);
        return false;
    } else if (height <= registration_height) {
        log::debug(
                logcat,
                "SN vote at height {} invalid: height <= reg height ({})",
                height,
                registration_height);
        return false;
    } else if (is_decommissioned() && height <= last_decommission_height) {
        log::debug(
                logcat,
                "SN vote at height {} invalid: height <= last decomm height ({})",
                height,
                last_decommission_height);
        return false;
    } else if (is_active()) {
        assert(active_since_height >= 0);  // should be satisfied whenever is_active() is true
        if (height <= static_cast<uint64_t>(active_since_height)) {
            log::debug(
                    logcat,
                    "SN vote at height {} invalid: height <= active-since height ({})",
                    height,
                    active_since_height);
            return false;
        }
    }

    log::trace(logcat, "SN vote at height {} is valid.", height);
    return true;
}

bool service_node_info::can_transition_to_state(
        hf hf_version, uint64_t height, new_state proposed_state) const {
    if (hf_version >= hf::hf13_enforce_checkpoints) {
        if (!can_be_voted_on(height)) {
            log::debug(
                    logcat, "SN state transition invalid: {} is not a valid vote height", height);
            return false;
        }

        if (proposed_state == new_state::deregister) {
            if (height <= registration_height) {
                log::debug(
                        logcat,
                        "SN deregister invalid: vote height ({}) <= registration_height ({})",
                        height,
                        registration_height);
                return false;
            }
        } else if (proposed_state == new_state::ip_change_penalty) {
            if (height <= last_ip_change_height) {
                log::debug(
                        logcat,
                        "SN ip change penality invalid: vote height ({}) <= last_ip_change_height "
                        "({})",
                        height,
                        last_ip_change_height);
                return false;
            }
        }
    } else {  // pre-HF13
        if (proposed_state == new_state::deregister) {
            if (height < registration_height) {
                log::debug(
                        logcat,
                        "SN deregister invalid: vote height ({}) < registration_height ({})",
                        height,
                        registration_height);
                return false;
            }
        }
    }

    if (is_decommissioned()) {
        if (proposed_state == new_state::decommission) {
            log::debug(logcat, "SN decommission invalid: already decommissioned");
            return false;
        } else if (proposed_state == new_state::ip_change_penalty) {
            log::debug(logcat, "SN ip change penalty invalid: currently decommissioned");
            return false;
        }
        return true;  // recomm or dereg
    } else if (proposed_state == new_state::recommission) {
        log::debug(logcat, "SN recommission invalid: not recommissioned");
        return false;
    }
    log::trace(logcat, "SN state change is valid");
    return true;
}

payout service_node_payout_portions(const crypto::public_key& key, const service_node_info& info) {
    service_nodes::payout result = {};
    result.key = key;

    // Add contributors and their portions to winners.
    result.payouts.reserve(info.contributors.size());
    const uint64_t portions_after_fee =
            cryptonote::old::STAKING_PORTIONS - info.portions_for_operator;
    for (const auto& contributor : info.contributors) {
        uint64_t portion =
                mul128_div64(contributor.amount, portions_after_fee, info.staking_requirement);

        if (contributor.address == info.operator_address)
            portion += info.portions_for_operator;
        result.payouts.push_back({contributor.address, portion});
    }

    return result;
}
}  // namespace service_nodes