/**********************************************************************

 *

 * GEOS - Geometry Engine Open Source

 * http://geos.osgeo.org

 *

 * Copyright (C) 2001-2002 Vivid Solutions Inc.

 *

 * This is free software; you can redistribute and/or modify it under

 * the terms of the GNU Lesser General Public Licence as published

 * by the Free Software Foundation.

 * See the COPYING file for more information.

 *

 **********************************************************************/

#pragma once

#include <geos/export.h>

#include <chrono>

#include <map>

#include <memory>

#include <iostream>

#include <string>

#include <vector>

#ifndef PROFILE

#define PROFILE 0

#endif

#ifdef _MSC_VER

#pragma warning(push)

#pragma warning(disable: 4251) // warning C4251: needs to have dll-interface to be used by clients of class

#endif

namespace geos {

namespace util {

/*

 * \class Profile utils.h geos.h

 *

 * \brief Profile statistics

 */

class GEOS_DLL Profile {

public:

    using timeunit = std::chrono::microseconds;

    /** \brief Create a named profile */

    Profile(std::string name);

    /** \brief Destructor */

    ~Profile() = default;

    /** \brief start a new timer */

    void

    start()

    {

        starttime = std::chrono::high_resolution_clock::now();

    }

    /** \brief stop current timer */

    void

    stop()

    {

        stoptime = std::chrono::high_resolution_clock::now();

        auto elapsed = std::chrono::duration_cast<timeunit>(stoptime - starttime);

        timings.push_back(elapsed);

        totaltime += elapsed;

        if(timings.size() == 1) {

            max = min = elapsed;

        }

        else {

            if(elapsed > max) {

                max = elapsed;

            }

            if(elapsed < min) {

                min = elapsed;

            }

        }

        avg = static_cast<double>(totaltime.count()) / static_cast<double>(timings.size());

    }

    /** \brief Return Max stored timing */

    double getMax() const;

    /** \brief Return Min stored timing */

    double getMin() const;

    /** \brief Return total timing */

    double getTot() const;

    /** \brief Return total timing */

    std::string getTotFormatted() const;

    /** \brief Return average timing */

    double getAvg() const;

    /** \brief Return number of timings */

    std::size_t getNumTimings() const;

    /** \brief Profile name */

    std::string name;

private:

    /* \brief current start and stop times */

    std::chrono::high_resolution_clock::time_point starttime, stoptime;

    /* \brief actual times */

    std::vector<timeunit> timings;

    /* \brief total time */

    timeunit totaltime;

    /* \brief max time */

    timeunit max;

    /* \brief max time */

    timeunit min;

    /* \brief avg time */

    double avg;

};

/*

 * \class Profiler utils.h geos.h

 *

 * \brief Profiling class

 *

 */

class GEOS_DLL Profiler {

public:

    Profiler() = default;

    ~Profiler() = default;

    Profiler(const Profiler&) = delete;

    Profiler& operator=(const Profiler&) = delete;

    /**

     * \brief

     * Return the singleton instance of the

     * profiler.

     */

    static Profiler* instance(void);

    /**

     * \brief

     * Start timer for named task. The task is

     * created if does not exist.

     */

    void start(std::string name);

    /**

     * \brief

     * Stop timer for named task.

     * Elapsed time is registered in the given task.

     */

    void stop(std::string name);

    /** \brief get Profile of named task */

    Profile* get(std::string name);

    std::map<std::string, std::unique_ptr<Profile>> profs;

};

/** \brief Return a string representing the Profile */

GEOS_DLL std::ostream& operator<< (std::ostream& os, const Profile&);

/** \brief Return a string representing the Profiler */

GEOS_DLL std::ostream& operator<< (std::ostream& os, const Profiler&);

} // namespace geos::util

} // namespace geos

#ifdef _MSC_VER

#pragma warning(pop)

#endif