//
// Keszitette: Toldi Balázs Ádám
// Datum: 2020. 03. 14.
//

#include "Block.h"

void Block::calculateHash() {
    memset(hash, 0, SHA256_DIGEST_LENGTH);
    SHA256_CTX sha;
    SHA256_Init(&sha);
    SHA256_Update(&sha, this, sizeof(Block));
    unsigned char md[SHA256_DIGEST_LENGTH];
    SHA256_Final(md, &sha);
    std::stringstream ss;
    for (unsigned char i : md)
        ss << std::hex << (int) i;
    strcpy(hash,ss.str().c_str());
}

Block::Block(Transaction tr[], size_t count, const char *prev_hash) {
    if(count > MAX_BLOCK_TRANSACTION) throw "Too much!";
    memset(transactions,0, sizeof(Transaction)*MAX_BLOCK_TRANSACTION);
    for (int i = 0; i < count; ++i) {
        transactions[i] = tr[i];
    }

    if (strcmp(prev_hash, "") == 0)
        memset(this->prev_hash, 0, SHA256_CBLOCK+1);
    else
        strcpy(this->prev_hash, prev_hash);
    calculateHash();
}

void Block::mine(size_t diff) {
    difficulty = diff;
    std::string str;
    for (int i = 0; i < diff; ++i) {
        str += '0';
    }

    while(strncmp(hash,str.c_str(),diff) != 0){
        nonce++;
        calculateHash();
        std::cout << nonce << std::endl;
    }
}

size_t Block::getDifficulty() const {
    return difficulty;
}

Transaction &Transaction::operator=(Transaction &tr) {
    if(this != &tr){
        strcpy(sender,tr.getSender());
        strcpy(reciver,tr.getReciever());
        strcpy(hash,tr.getHash());
        amount = tr.getAmount();
    }
    return *this;
}

void Transaction::calculateHash() {
    memset(hash, 0, SHA256_DIGEST_LENGTH);
    SHA256_CTX sha;
    SHA256_Init(&sha);
    SHA256_Update(&sha, this, sizeof(Transaction));
    unsigned char md[SHA256_DIGEST_LENGTH];
    SHA256_Final(md, &sha);
    std::stringstream ss;
    for (unsigned char i : md)
        ss << std::hex << (int) i;
    strcpy(hash,ss.str().c_str());
}