void save_current_id_in_map_to_file(int id) {
    ofstream file;
    string file_name = "/home/twite/CLionProjects/Database/map.dat";
    file.open(file_name, ios::out | ios::app);
    file << "id" << "\n" << id << "\n" << "--" << "\n";
    file << "file_names" << "\n";
    for (const auto& current_filename: indexes[id].file_names) {
        file << current_filename << "\n";
    }
    file << "--" << "\n";
    file << "start_reading_positions" << "\n";
    for (const auto& current_start_read_pos: indexes[id].start_reading_positions) {
        file << current_start_read_pos << "\n";
    }
    file << "--" "\n";
    file << "end_reading_positions" << "\n";
    for (const auto& current_end_read_pos: indexes[id].end_reading_positions) {
        file << current_end_read_pos << "\n";
    }
    file << "--" "\n";
    file << "data_size" << "\n";
    file << indexes[id].data_size << "\n";
    file << "--" << "\n";
}

void load_map_from_file() {
    int id;
    index_data current_id;
    ifstream file;
    string file_name = "/home/twite/CLionProjects/Database/map.dat";
    file.open(file_name);
    string s;
    int a;
    streamoff b;
    while (getline (file, s)) {
        if (s == "id") {
            getline (file, s);
            istringstream iss(s);
            iss >> a;
            id = a;
        }
        if (s == "file_names") {
            while (getline(file, s)) {
                if (s == "--") {
                    break;
                }
                current_id.file_names.push_back(s);
            }
        }
        if (s == "start_reading_positions") {
            while (getline(file, s)) {
                if (s == "--") {
                    break;
                }
                istringstream iss(s);
                iss >> b;
                current_id.start_reading_positions.push_back(b);
            }
        }
        if (s == "end_reading_positions") {
            while (getline(file, s)) {
                if (s == "--") {
                    break;
                }
                istringstream iss(s);
                iss >> b;
                current_id.end_reading_positions.push_back(b);
            }
        }
        if (s == "data_size") {
            getline(file, s);
            istringstream iss(s);
            iss >> a;
            current_id.data_size = a;
            indexes[id] = current_id;
            current_id.file_names.clear();
            current_id.start_reading_positions.clear();
            current_id.end_reading_positions.clear();
        }
    }
}