/*
 * This file is part of the Flowee project
 * Copyright (C) 2026 Tom Zander <tom@flowee.org>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#include "BlockHeader.h"
#include "Block.h"
#include <hash.h>

BlockHeader::BlockHeader(const Block &block)
    : nVersion(block.blockVersion()),
    hashPrevBlock(block.previousBlockId()),
    hashMerkleRoot(block.merkleRoot()),
    nTime(block.timestamp()),
    nBits(block.bits()),
    nNonce(block.nonce())
{
}

uint256 BlockHeader::createHash() const
{
    uint8_t header[80];
    *reinterpret_cast<uint32_t*>(header) = nVersion;
    memcpy(header + 4, hashPrevBlock.begin(), 32);
    memcpy(header + 36, hashMerkleRoot.begin(), 32);
    *reinterpret_cast<uint32_t*>(header + 68) = nTime;
    *reinterpret_cast<uint32_t*>(header + 72) = nBits;
    *reinterpret_cast<uint32_t*>(header + 76) = nNonce;

    CHash256 ctx;
    ctx.write(header, 80);
    uint256 result;
    ctx.finalize((unsigned char*)&result);
    return result;
}