indicators/include/progress/bar.hpp

#pragma once
#include <iostream>
#include <string>
#include <atomic>
#include <mutex>
#include <thread>

class ProgressBar {
  float _progress{0.0};
  size_t _bar_width{100};  
  std::string _start{"["};
  std::string _fill{"="};
  std::string _lead{">"};
  std::string _remainder{" "};
  std::string _end{"]"};
  std::atomic<bool> _completed{false};
  std::atomic<bool> _show_percentage{true};  
  std::mutex _mutex;

  void _print_progress() {
    std::unique_lock<std::mutex> lock{_mutex};    
    std::cout << _start;
    float pos = _progress * static_cast<float>(_bar_width) / 100.0;
    for (size_t i = 0; i < _bar_width; ++i) {
      if (i < pos) std::cout << _fill;
      else if (i == pos) std::cout << _lead;
      else std::cout << _remainder;
    }
    std::cout << _end;
    if (_show_percentage)
      std::cout << " " << static_cast<int>(_progress) << "%\r";
    else
      std::cout << "\r";
    std::cout.flush();
    if (_completed)
      std::cout << std::endl;    
  }

public:

  void bar_width(size_t bar_width) {
    std::unique_lock<std::mutex> lock{_mutex};
    _bar_width = bar_width;
  }

  void start_with(const std::string& start) {
    std::unique_lock<std::mutex> lock{_mutex};
    _start = start;
  }

  void fill_progress_with(const std::string& fill) {
    std::unique_lock<std::mutex> lock{_mutex};    
    _fill = fill;
  }

  void lead_progress_with(const std::string& lead) {
    std::unique_lock<std::mutex> lock{_mutex};    
    _lead = lead;
  }

  void fill_remainder_with(const std::string& remainder) {
    std::unique_lock<std::mutex> lock{_mutex};    
    _remainder = remainder;
  }    

  void end_with(const std::string& end) {
    std::unique_lock<std::mutex> lock{_mutex};    
    _end = end;
  }

  void show_percentage(bool flag) {
    _show_percentage = flag;
  }

  void set_progress(float value) {
    {
      std::unique_lock<std::mutex> lock{_mutex};
      if (_completed) return;
      _progress = value;
      if (_progress >= 100.0) {
	_completed = true;
      }
    }
    _print_progress();
  }

  void tick() {
    {
      std::unique_lock<std::mutex> lock{_mutex};
      if (_completed) return;
      _progress += 1;
      if (_progress >= 100.0) {
	_completed = true;
      }
    }
    _print_progress();
  }

  bool completed() {
    return _completed;
  }
  
};