// Copyright (c) 2020 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 <primitives/block.h>

#include <test/fuzz/FuzzedDataProvider.h>

#include <test/fuzz/fuzz.h>

#include <test/fuzz/util.h>

#include <uint256.h>

#include <cassert>

#include <cstdint>

#include <optional>

#include <string>

#include <vector>

FUZZ_TARGET(block_header)

{

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

    const std::optional<CBlockHeader> block_header = ConsumeDeserializable<CBlockHeader>(fuzzed_data_provider);

    if (!block_header) {

        return;

    }

    {

        const uint256 hash = block_header->GetHash();

        constexpr uint256 u256_max{"ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"};

        assert(hash != u256_max);

        assert(block_header->GetBlockTime() == block_header->nTime);

        assert(block_header->IsNull() == (block_header->nBits == 0));

    }

    {

        CBlockHeader mut_block_header = *block_header;

        mut_block_header.SetNull();

        assert(mut_block_header.IsNull());

        CBlock block{*block_header};

        assert(block.GetBlockHeader().GetHash() == block_header->GetHash());

        (void)block.ToString();

        block.SetNull();

        assert(block.GetBlockHeader().GetHash() == mut_block_header.GetHash());

    }

    {

        std::optional<CBlockLocator> block_locator = ConsumeDeserializable<CBlockLocator>(fuzzed_data_provider);

        if (block_locator) {

            (void)block_locator->IsNull();

            block_locator->SetNull();

            assert(block_locator->IsNull());

        }

    }

}