// Copyright (c) 2020-present The Bitcoin Core developers

// Distributed under the MIT software license, see the accompanying

// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include <addrman.h>

#include <banman.h>

#include <kernel/chainparams.h>

#include <net.h>

#include <net_processing.h>

#include <primitives/block.h>

#include <primitives/transaction.h>

#include <protocol.h>

#include <sync.h>

#include <test/fuzz/FuzzedDataProvider.h>

#include <test/fuzz/fuzz.h>

#include <test/fuzz/util.h>

#include <test/fuzz/util/net.h>

#include <test/util/net.h>

#include <test/util/random.h>

#include <test/util/setup_common.h>

#include <test/util/time.h>

#include <test/util/validation.h>

#include <uint256.h>

#include <util/check.h>

#include <util/time.h>

#include <validation.h>

#include <validationinterface.h>

#include <algorithm>

#include <array>

#include <cstdlib>

#include <functional>

#include <iostream>

#include <memory>

#include <optional>

#include <string>

#include <string_view>

#include <utility>

#include <vector>

namespace {

TestingSetup* g_setup;

std::string_view LIMIT_TO_MESSAGE_TYPE{};

} // namespace

extern void MakeRandDeterministicDANGEROUS(const uint256& seed) noexcept;

void initialize_process_message()

{

    FakeNodeClock init_clock{}; // Uses the existing mock time

    if (const auto val{std::getenv("LIMIT_TO_MESSAGE_TYPE")}) {

  Branch (52:20): [True: 0, False: 0]

        LIMIT_TO_MESSAGE_TYPE = val;

        Assert(std::count(ALL_NET_MESSAGE_TYPES.begin(), ALL_NET_MESSAGE_TYPES.end(), LIMIT_TO_MESSAGE_TYPE)); // Unknown message type passed

    }

    static const auto testing_setup{

        MakeNoLogFileContext<TestingSetup>(

            /*chain_type=*/ChainType::REGTEST,

            {}),

    };

    g_setup = testing_setup.get();

    ResetChainmanAndMempool(*g_setup, init_clock);

}

FUZZ_TARGET(process_message, .init = initialize_process_message)

{

    SeedRandomStateForTest(SeedRand::ZEROS);

    FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());

    auto& node{g_setup->m_node};

    auto& connman{static_cast<ConnmanTestMsg&>(*node.connman)};

    connman.Reset();

    auto& chainman{static_cast<TestChainstateManager&>(*node.chainman)};

    const auto block_index_size{WITH_LOCK(chainman.GetMutex(), return chainman.BlockIndex().size())};

    const auto initial_sequence{WITH_LOCK(node.mempool->cs, return node.mempool->GetSequence())};

    FakeNodeClock node_clock{1610000000s}; // 2021-01-07, arbitrary

    FakeSteadyClock steady_clock;

    chainman.ResetIbd();

    chainman.DisableNextWrite();

    // Reset, so that dangling pointers can be detected by sanitizers.

    node.banman.reset();

    node.addrman.reset();

    node.peerman.reset();

    node.addrman = std::make_unique<AddrMan>(*node.netgroupman, /*deterministic=*/true, /*consistency_check_ratio=*/0);

    node.peerman = PeerManager::make(connman, *node.addrman,

                                     /*banman=*/nullptr, chainman,

                                     *node.mempool, *node.warnings,

                                     PeerManager::Options{

                                         .reconcile_txs = true,

                                         .deterministic_rng = true,

                                     });

    connman.SetMsgProc(node.peerman.get());

    connman.SetAddrman(*node.addrman);

    LOCK(NetEventsInterface::g_msgproc_mutex);

    const std::string random_message_type{fuzzed_data_provider.ConsumeBytesAsString(CMessageHeader::MESSAGE_TYPE_SIZE).c_str()};

    if (!LIMIT_TO_MESSAGE_TYPE.empty() && random_message_type != LIMIT_TO_MESSAGE_TYPE) {

  Branch (100:9): [True: 0, False: 0]
  Branch (100:43): [True: 0, False: 0]

        return;

    }

    node.validation_signals->RegisterValidationInterface(node.peerman.get());

    CNode& p2p_node = *ConsumeNodeAsUniquePtr(fuzzed_data_provider, steady_clock).release();

    connman.AddTestNode(p2p_node);

    FillNode(fuzzed_data_provider, connman, p2p_node);

    node_clock.set(ConsumeTime(fuzzed_data_provider));

    CSerializedNetMsg net_msg;

    net_msg.m_type = random_message_type;

    net_msg.data = ConsumeRandomLengthByteVector(fuzzed_data_provider, MAX_PROTOCOL_MESSAGE_LENGTH);

    connman.FlushSendBuffer(p2p_node);

    (void)connman.ReceiveMsgFrom(p2p_node, std::move(net_msg));

    if (fuzzed_data_provider.ConsumeBool()) {

  Branch (120:9): [True: 0, False: 0]

        chainman.JumpOutOfIbd();

    }

    bool more_work{true};

    while (more_work) {

  Branch (125:12): [True: 0, False: 0]

        p2p_node.fPauseSend = false;

        try {

            more_work = connman.ProcessMessagesOnce(p2p_node);

        } catch (const std::ios_base::failure&) {

        }

        node.peerman->SendMessages(p2p_node);

    }

    node.validation_signals->SyncWithValidationInterfaceQueue();

    node.validation_signals->UnregisterValidationInterface(node.peerman.get());

    node.connman->StopNodes();

    const auto end_sequence{WITH_LOCK(node.mempool->cs, return node.mempool->GetSequence())};

    if (block_index_size != WITH_LOCK(chainman.GetMutex(), return chainman.BlockIndex().size()) || initial_sequence != end_sequence) {

  Branch (137:9): [True: 0, False: 0]
  Branch (137:9): [True: 0, False: 0]
  Branch (137:100): [True: 0, False: 0]

        // Reuse the global chainman and mempool, but reset them when dirty.

        MakeRandDeterministicDANGEROUS(uint256::ZERO);

        ResetChainmanAndMempool(*g_setup, node_clock);

    }

}