decoder.h

/*
nexus433
Copyright (C) 2018 aquaticus

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#pragma once

#include <condition_variable>
#include <thread>
#include <future>
#include <gpiod.h>
#include <condition_variable>
#include "istorage.h"
#include "idecoder.h"
#include "diag.h"

class Decoder : public IDecoder
{
public:
	typedef enum _STATES
	{
		STATE_UNKNOWN,
		STATE_PULSE_START,
		STATE_PULSE_END,
	} STATES;

	Decoder(IStorage& s, gpiod_line *line, int tolerance, int precision, bool polling):
	m_Storage(s),
    m_Line(line),
	m_ToleranceUs(tolerance),
	m_ResolutionUs(precision),
	m_Polling(polling)
	{
		m_pThread = NULL;
		m_ErrorStop = false;
	}

	virtual ~Decoder()
	{
		if( m_pThread )
		{
		    delete m_pThread;
		}
	}

	void Terminate();
	void Start();

	bool IsErrorStop()
	{
		return m_ErrorStop;
	}

	bool WaitForTermination( uint16_t milliseconds);

protected:
	void ThreadFunc();
	void PollingReader();
	void EventReader();
	void Decode(bool risingEdge, long long delta);

	IStorage& m_Storage;
	std::promise<void> m_StopFlag;
	std::thread* m_pThread;

	STATES m_State=STATE_UNKNOWN;
	uint8_t m_BitCount=0;
	uint64_t m_Bits=0;
	gpiod_line* m_Line;
	int m_ToleranceUs; // +/- tolerance in microseconds, default 150
	int m_ResolutionUs; // how long go to sleep in microseconds. Lower number (0 best) better precision but higher system load
	bool m_Polling; // true to use polling, false to use events
	std::atomic<bool> m_ErrorStop;
	std::future<void> m_Future;
};