/*
 * This file is a part of Winix
 * and is not publicly distributed
 * 
 * Copyright (c) 2008-2014, Tomasz Sowa
 * All rights reserved.
 * 
 */
 
#ifndef headerfile_winix_core_loadavg
#define headerfile_winix_core_loadavg

#include <ctime>


namespace Winix
{




// in seconds
#define WINIX_LOADAVG_GRANULARITY1		2
#define WINIX_LOADAVG_GRANULARITY5		15
#define WINIX_LOADAVG_GRANULARITY15		45



class LoadAvg
{
public:
	LoadAvg();
	~LoadAvg();
	LoadAvg & operator=(const LoadAvg & l);
	LoadAvg(const LoadAvg & l);

	void StartRequest();
	void StopRequest();

	double LoadAvgNow(); // load average withing last WINIX_LOADAVG_GRANULARITY1 seconds
	double LoadAvg1();
	double LoadAvg5();
	double LoadAvg15();

	double ReqPerSecNow();
	double ReqPerSec1();
	double ReqPerSec5();
	double ReqPerSec15();

private:

	struct Times
	{
		double dr; // time for the request (in seconds)
		double dp; // time for the pause between requestes (in seconds)
		long req;  // how many requests 

		void Clear()
		{
			dr  = 0.0;
			dp  = 0.0;
			req = 0;
		}

		Times & operator=(const Times & t)
		{
			dr  = t.dr;
			dp  = t.dp;
			req = t.req;

		return *this;
		}
	};

	void CheckTimers();
	void UpdateTimer1();
	void UpdateTimer5();
	void UpdateTimer15();

	Times current1;
	Times current5;
	Times current15;

	void CreateTable(size_t seconds, size_t granulatiry, Times* & tab, size_t & len);
	void CreateTable();

	void MoveTab(Times * tab, size_t len);
	void SumTab(Times * tab, size_t len, double expected, Times & t);

	void Calculate1();
	void Calculate5();
	void Calculate15();

	bool was_stop_request;
	timespec start_req, stop_req;
	
	Times * tab1;
	size_t len1;

	Times * tab5;
	size_t len5;

	Times * tab15;
	size_t len15;

	double cache_load1;
	double cache_load5;
	double cache_load15;

	double cache_req_per_sec1;
	double cache_req_per_sec5;
	double cache_req_per_sec15;
};



} // namespace Winix



#endif