miner.cpp

#include <iostream>
#include <string>
#include <chrono>
#include <sstream>

// A simple structure representing a Bitcoin-style Block Header
struct BlockHeader {
    int version = 1;
    std::string prevHash = "00000000000000000000000000000000";
    std::string merkleRoot = "a1b2c3d4e5f6g7h8i9j0";
    long timestamp = std::time(0);
    int difficulty = 4; // Number of leading zeros required
    long nonce = 0;     // The variable we change to "mine"
};

// A mock hash function to simulate the hashing process
std::string simpleHash(std::string data) {
    unsigned long hash = 5381;
    for (char c : data) {
        hash = ((hash << 5) + hash) + c; // djb2 algorithm
    }
    std::stringstream ss;
    ss << std::hex << hash;
    return ss.str();
}

void mineBlock(BlockHeader& header) {
    std::string hash = "";
    std::string target(header.difficulty, '0'); // e.g., "0000"

    std::cout << "Mining started with difficulty: " << header.difficulty << "...\n";

    auto start = std::chrono::high_resolution_clock::now();

    while (true) {
        // Construct a string of the header data
        std::string headerData = std::to_string(header.version) + header.prevHash + 
                                 header.merkleRoot + std::to_string(header.nonce);
        
        hash = simpleHash(headerData);

        // Check if the hash starts with our target zeros
        if (hash.substr(0, header.difficulty) == target) {
            auto end = std::chrono::high_resolution_clock::now();
            std::chrono::duration<double> diff = end - start;
            
            std::cout << "\n[SUCCESS] Block Mined!\n";
            std::cout << "Hash: " << hash << "\n";
            std::cout << "Nonce: " << header.nonce << "\n";
            std::cout << "Time taken: " << diff.count() << " seconds\n";
            break;
        }
        
        header.nonce++; // Try the next number
        if (header.nonce % 100000 == 0) std::cout << "."; // Progress indicator
    }
}

int main() {
    BlockHeader newBlock;
    mineBlock(newBlock);
    return 0;
}