PDS/homework_2/include/utils.hpp

/**
 * \file    utils.hpp
 * \brief   Utilities header
 *
 * \author
 *    Christos Choutouridis AEM:8997
 *    <cchoutou@ece.auth.gr>
 */
#ifndef UTILS_HPP_
#define UTILS_HPP_

#include <iostream>
#include <chrono>
#include <unistd.h>

#include "matrix.hpp"
#include "config.h"

/*!
 * A Logger for entire program.
 */
struct Log {
   struct Endl {} endl;    //!< a tag object to to use it as a new line request.

   //! We provide logging via << operator
   template<typename T>
   Log& operator<< (T&& t) {
      if (session.verbose) {
         if (line_) {
            std::cout << "[Log]: " << t;
            line_ = false;
         }
         else
            std::cout << t;
      }
      return *this;
   }
   // overload for special end line handling
   Log& operator<< (Endl e) { (void)e;
      if (session.verbose) {
         std::cout << '\n';
         line_ = true;
      }
      return *this;
   }
private:
   bool line_ {true};
};

extern Log logger;

/*!
 * A small timing utility based on chrono.
 */
struct Timing{
   using Tpoint = std::chrono::steady_clock::time_point;
   using microseconds = std::chrono::microseconds;
   using milliseconds = std::chrono::milliseconds;
   using seconds = std::chrono::seconds;

   //! tool to mark the starting point
   Tpoint start () noexcept { return start_ = std::chrono::steady_clock::now(); }
   //! tool to mark the ending point
   Tpoint stop ()  noexcept { return stop_ = std::chrono::steady_clock::now(); }

   auto dt () noexcept {
      return std::chrono::duration_cast<std::chrono::microseconds>(stop_ - start_).count();
   }
   //! tool to print the time interval
   void print_dt (const char* what) noexcept {
      if (session.timing) {
         auto t = stop_ - start_;
         if       (std::chrono::duration_cast<microseconds>(t).count() < 10000)
            std::cout << "[Timing]: " << what << ": " << std::to_string(std::chrono::duration_cast<microseconds>(t).count()) << " [usec]\n";
         else if (std::chrono::duration_cast<milliseconds>(t).count() < 10000)
            std::cout << "[Timing]: " << what << ": " << std::to_string(std::chrono::duration_cast<milliseconds>(t).count()) << " [msec]\n";
         else
            std::cout << "[Timing]: " << what << ": " << std::to_string(std::chrono::duration_cast<seconds>(t).count()) << " [sec]\n";
      }
   }
private:
   Tpoint start_;
   Tpoint stop_;
};


#endif /* UTILS_HPP_ */