Block.cpp

#include <sstream>
#include "Blockchain.h"
#include "sha256.h"
using namespace std;

Block::Block(uint32_t nIndexIn, const string &sDataIn) : _nIndex(nIndexIn), _sData(sDataIn) {
	_nNonce = -1;
	_tTime = time(nullptr);
}

string Block::GetHash() { 
	return _sHash;
}

void Block::MineBlock(uint32_t nDifficulty) { 
	char cstr[nDifficulty + 1];
	for (uint32_t i = 0; i < nDifficulty; ++i) { 
		cstr[i] = '0';
	}
	cstr[nDifficulty] = '\0';

	string str(cstr);

	do {
		_nNonce++;
		_sHash = _CalculateHash();
	} while (_sHash.substr(0, nDifficulty) != str);

	cout << "Block mined: " << _sHash << endl;
}

inline string Block::_CalculateHash() const { 
	stringstream ss;
	ss << _nIndex << _tTime << _sData << _nNonce << sPrevHash;

	return sha256(ss.str());
}

void Blockchain::AddBlock(Block bNew) { 
	bNew.sPrevHash = _GetLastBlock().GetHash();
	bNew.MineBlock(_nDifficulty);
	_vChain.push_back(bNew);
}

Block Blockchain::_GetLastBlock() const {
	return _vChain.back();
}