//(c) 2013-2016 by Authors
//This file is a part of Ragout program.
//Released under the BSD license (see LICENSE file)

#pragma once

#include <atomic>
#include <iostream>

class ProgressPercent
{
public:
	ProgressPercent(size_t finalCount = 0):
		_finalCount(finalCount), _curCount(0), _prevPercent(-1),
		_stopped(false)
	{}

	void setFinalCount(size_t finalCount) {_finalCount = finalCount;}
	void setValue(size_t value)
	{
		this->advance(value - _curCount);
	}
	void setDone()
	{
		this->setValue(_finalCount);
	}
	void advance(size_t step = 1)
	{
		if (_stopped) return;

		_curCount += step;
		int percent = 10UL * _curCount / _finalCount;

		if (percent > _prevPercent)
		{
			int expected = _prevPercent;
			if (_prevPercent.compare_exchange_weak(expected, percent))
			{
				std::cerr << percent * 10 << "% ";
				if (percent >= 10)
				{
					std::cerr << std::endl;
					_stopped = true;
				}
			}
		}
	}

private:
	size_t 			    _finalCount;
	std::atomic<size_t> _curCount;
	std::atomic<int>  	_prevPercent;
	bool 				_stopped;
};