Logger using variadic templating

logger.hpp

#pragma once
#include <algorithm>
#include <fstream>
#include <iostream>
#include <sstream>
#include <string>
#include <utilities/helpers.hpp>

class Logger {
 public:
  enum LogLevel_e : uint8_t { DEBUG, INFO, WARN, ERROR, FATAL, NUM_LOG_LEVELS };

 protected:
  std::string checkLogLevel(LogLevel_e log_level) {
    static const std::array<std::string, NUM_LOG_LEVELS> logLevelStrings = {
        "DEBUG", "INFO", "WARN", "ERROR", "FATAL"};

    if (log_level >= 0 && log_level < NUM_LOG_LEVELS)
      return logLevelStrings[log_level];

    return "UNKNOWN";
  }

  template <typename... Args>
  std::string handleInput(Args... args) {
    std::stringstream ss;
    // Fold expression to concatenate arguments
    (ss << ... << args);
    std::string message = ss.str();
    return message;
  }

  virtual std::string getID() { return std::string(""); };

 public:
  Logger() = default;
  virtual ~Logger() = default;

  template <typename... Args>
  std::string format_string(const std::string& format, Args... args) {
    int size_s = std::snprintf(nullptr, 0, format.c_str(), args...) +
                 1;  // Extra space for '\0'
    if (size_s <= 0) {
      std::cout << "Error during formatting.";
      return "";
    }
    auto size = static_cast<size_t>(size_s);
    std::unique_ptr<char[]> buf(new char[size]);
    std::snprintf(buf.get(), size, format.c_str(), args...);
    return std::string(buf.get(),
                       buf.get() + size - 1);  // We don't want the '\0' inside
  }

  // Templated log function to handle various data types and arguments
  template <typename... Args>
  void log(LogLevel_e log_level, Args... args) {
    std::string message = handleInput(args...);
    std::string logLevel = checkLogLevel(log_level);
    std::string logMessage =
        format_string("[%s - %s]: %s", logLevel.c_str(), this->getID().c_str(),
                      message.c_str());
    std::cout << logMessage << '\n';
  }
  template <typename... Args>
  void log(Args... args) {
    std::string message = handleInput(args...);
    std::string logLevel = checkLogLevel(LogLevel_e::INFO);
    std::string logMessage =
        Helpers::format_string("[%s - %s]: %s", logLevel.c_str(),
                               this->getID().c_str(), message.c_str());
    std::cout << logMessage << '\n';
  }
};
typedef Logger::LogLevel_e LogLevel_t;