/* SPDX-License-Identifier: MIT */
/**
	@file		performance.h
	@brief		Declaration of the AJAPerformance class.
	@copyright	(C) 2011-2021 AJA Video Systems, Inc.  All rights reserved.
**/

#ifndef AJA_PERFORMANCE_H
#define AJA_PERFORMANCE_H

/////////////////////////////
// Includes
/////////////////////////////
#include "ajabase/common/timer.h"
#include <string>
#include <map>

typedef std::map<std::string, uint64_t> AJAPerformanceExtraMap;

/////////////////////////////
// Declarations
/////////////////////////////
class AJAExport AJAPerformance
{
	public:
		/**
		 *	Constructor
		 *
		 *	@param[in]	name The name for the performance object.
		 *	@param[in]	precision The Precision units to use.
		 *	@param[in]	skipEntries The number of entries to skip over before tracking performance,
		 *							the idea here is to skip over any "warm-up" period.
		 */
		AJAPerformance(const std::string& name,
					   AJATimerPrecision precision = AJATimerPrecisionMilliseconds,
					   uint64_t skipEntries = 0);

		/**
		 *	Constructor
		 *
		 *	@param[in]	name The name for the performance object.
		 *	@param[in]	values Extra values that can be stored along with performance info.
		 *	@param[in]	precision The Precision units to use.
		 *	@param[in]	skipEntries The number of entries to skip over before tracking performance,
		 *							the idea here is to skip over any "warm-up" period.
		 */
		AJAPerformance(const std::string& name, const AJAPerformanceExtraMap& values,
					   AJATimerPrecision precision = AJATimerPrecisionMilliseconds,
					   uint64_t skipEntries = 0);

		/**
		 *	Constructor
		 *
		 *	@param[in]	precision The Precision units to use.
		 *	@param[in]	skipEntries The number of entries to skip over before tracking performance,
		 *							the idea here is to skip over any "warm-up" period.
		 */
		AJAPerformance(AJATimerPrecision precision = AJATimerPrecisionMilliseconds,
					   uint64_t skipEntries = 0);

		~AJAPerformance(void);

		/**
		 *	Set extra values that can be stored along with performance info
		 *
		 *	@param[in]	values The extra values to assign to this object
		 */
		void SetExtras(const AJAPerformanceExtraMap& values);

		/**
		 *	Start the timer of the performance object
		 */
		void Start(void);

		/**
		 *	Stop the timer of the performance object and updates the performance stats:
		 *	number of entries, min time, max time, total time
		 */
		void Stop(void);

		/**
		 *	Print out a performance report to AJADebug
		 *	@param[in]	name Name to use in printout, if empty will use the name passed in constructor
		 *	@param[in]	pFileName	The source filename reporting the performace.
		 *	@param[in]	lineNumber	The line number in the source file reporting the performance.
		 */
		void Report(const std::string& name = "", const char *pFileName = NULL, int32_t lineNumber = -1);

		/**
		 *	Returns the name for the performance object that was set in the constructor
		 */
		std::string Name(void);

		/**
		 *	Returns the Precision units set in the constructor
		 */
		AJATimerPrecision Precision(void);

		/**
		 *	Returns the number of times that the start/stop pair has been called
		 */
		uint64_t Entries(void);

		/**
		 *	Returns the total elapsed time between all start/stop pairs (in Precision units)
		 */
		uint64_t TotalTime(void);

		/**
		 *	Returns the minimum time between all start/stop pairs (in Precision units)
		 */
		uint64_t MinTime(void);

		/**
		 *	Returns the maximum time between all start/stop pairs (in Precision units)
		 */
		uint64_t MaxTime(void);

		/**
		 *	Returns the mean (average) time of all start/stop pairs (in Precision units)
		 */
		double Mean(void);

		/**
		 *	Returns the variance of all start/stop pairs (in Precision units)
		 */
		double Variance(void);

		/**
		 *	Returns the standard deviation of all start/stop pairs (in Precision units)
		 */
		double StandardDeviation(void);

		/**
		 *	Returns a map of any extra values stored in the performance object
		 */
		const AJAPerformanceExtraMap Extras(void);

	private:
		AJATimer					mTimer;
		std::string					mName;
		uint64_t					mTotalTime;
		uint64_t					mEntries;
		uint64_t					mMinTime;
		uint64_t					mMaxTime;
		double						mMean;
		double						mM2;
		uint64_t					mNumEntriesToSkipAtStart;

		AJAPerformanceExtraMap		mExtras;
};

// Helper functions to track/report many performance timers and store in a map
typedef std::map<std::string, AJAPerformance> AJAPerformanceTracking;

extern bool AJAPerformanceTracking_start(AJAPerformanceTracking& stats,
										std::string key,
										AJATimerPrecision precision = AJATimerPrecisionMilliseconds,
										uint64_t skipEntries = 0);

extern bool AJAPerformanceTracking_start(AJAPerformanceTracking& stats,
										std::string key, const AJAPerformanceExtraMap& extras,
										AJATimerPrecision precision = AJATimerPrecisionMilliseconds,
										uint64_t skipEntries = 0);

extern bool AJAPerformanceTracking_stop(AJAPerformanceTracking& stats, std::string key);

extern bool AJAPerformanceTracking_report(AJAPerformanceTracking& stats, std::string title = "",
										 const char *pFileName = NULL, int32_t lineNumber = -1);


#endif // AJA_PERFORMANCE_H
//////////////////////// End of performance.h ///////////////////////