/*

-----------------------------------------------------------------------------

This source file is part of OGRE

    (Object-oriented Graphics Rendering Engine)

For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2014 Torus Knot Software Ltd

Permission is hereby granted, free of charge, to any person obtaining a copy

of this software and associated documentation files (the "Software"), to deal

in the Software without restriction, including without limitation the rights

to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

copies of the Software, and to permit persons to whom the Software is

furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in

all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

THE SOFTWARE.

-----------------------------------------------------------------------------

*/

#include "OgreStableHeaders.h"

/*

    Although the code is original, many of the ideas for the profiler were borrowed from 

"Real-Time In-Game Profiling" by Steve Rabin which can be found in Game Programming

Gems 1.

    This code can easily be adapted to your own non-Ogre project. The only code that is 

Ogre-dependent is in the visualization/logging routines and the use of the Timer class.

    Enjoy!

*/

#include "OgreTimer.h"

#ifdef USE_REMOTERY

#include "Remotery.h"

static Remotery* rmt;

#endif

namespace Ogre {

    //-----------------------------------------------------------------------

    // PROFILE DEFINITIONS

    //-----------------------------------------------------------------------

    template<> Profiler* Singleton<Profiler>::msSingleton = 0;

    Profiler* Profiler::getSingletonPtr(void)

    {

        return msSingleton;

    }

    Profiler& Profiler::getSingleton(void)

    {  

        assert( msSingleton );  return ( *msSingleton );  

    }

    //-----------------------------------------------------------------------

    // PROFILER DEFINITIONS

    //-----------------------------------------------------------------------

    Profiler::Profiler() 

        : mCurrent(&mRoot)

        , mLast(NULL)

        , mRoot()

        , mInitialized(false)

        , mUpdateDisplayFrequency(10)

        , mCurrentFrame(0)

        , mTimer(0)

        , mTotalFrameTime(0)

        , mEnabled(false)

        , mNewEnableState(false)

        , mProfileMask(0xFFFFFFFF)

        , mMaxTotalFrameTime(0)

        , mAverageFrameTime(0)

        , mResetExtents(false)

    {

        mRoot.hierarchicalLvl = 0 - 1;

#ifdef USE_REMOTERY

        rmt_Settings()->reuse_open_port = true;

        if(auto error = rmt_CreateGlobalInstance(&rmt))

        {

            LogManager::getSingleton().logError("Could not launch Remotery - RMT_ERROR " + std::to_string(error));

            return;

        }

        rmt_SetCurrentThreadName("Ogre Main");

#endif

    }

    //-----------------------------------------------------------------------

    ProfileInstance::ProfileInstance(void)

        : parent(NULL)

        , frameNumber(0)

        , accum(0)

        , hierarchicalLvl(0)

    {

        history.numCallsThisFrame = 0;

        history.totalTimePercent = 0;

        history.totalTimeMillisecs = 0;

        history.totalCalls = 0;

        history.maxTimePercent = 0;

        history.maxTimeMillisecs = 0;

        history.minTimePercent = 1;

        history.minTimeMillisecs = 100000;

        history.currentTimePercent = 0;

        history.currentTimeMillisecs = 0;

        frame.frameTime = 0;

        frame.calls = 0;

    }

    ProfileInstance::~ProfileInstance(void)

    {                                        

        for(auto & it : children)

        {

            ProfileInstance* instance = it.second;

            OGRE_DELETE instance;

        }

        children.clear();

    }

    //-----------------------------------------------------------------------

    Profiler::~Profiler()

    {

#ifdef USE_REMOTERY

        rmt_DestroyGlobalInstance(rmt);

#else

        if (!mRoot.children.empty()) 

        {

            // log the results of our profiling before we quit

            logResults();

        }

        // clear all our lists

        mDisabledProfiles.clear();

#endif

    }

    //-----------------------------------------------------------------------

    void Profiler::setTimer(Timer* t)

    {

        mTimer = t;

    }

    //-----------------------------------------------------------------------

    Timer* Profiler::getTimer()

    {

        assert(mTimer && "Timer not set!");

        return mTimer;

    }

    //-----------------------------------------------------------------------

    void Profiler::setEnabled(bool enabled) 

    {

        if (!mInitialized && enabled) 

        {

            for(auto & l : mListeners)

                l->initializeSession();

            mInitialized = true;

        }

        else if (mInitialized && !enabled)

        {

            for(auto & l : mListeners)

                l->finializeSession();

            mInitialized = false;

        }

        // We store this enable/disable request until the frame ends

        // (don't want to screw up any open profiles!)

        mNewEnableState = enabled;

    }

    //-----------------------------------------------------------------------

    bool Profiler::getEnabled() const

    {

        return mEnabled;

    }

    //-----------------------------------------------------------------------

    void Profiler::changeEnableState() 

    {

        for(auto & l : mListeners)

            l->changeEnableState(mNewEnableState);

        mEnabled = mNewEnableState;

    }

    //-----------------------------------------------------------------------

    void Profiler::disableProfile(const String& profileName)

    {

        // even if we are in the middle of this profile, endProfile() will still end it.

        mDisabledProfiles.insert(profileName);

    }

    //-----------------------------------------------------------------------

    void Profiler::enableProfile(const String& profileName) 

    {

        mDisabledProfiles.erase(profileName);

    }

    //-----------------------------------------------------------------------

    void Profiler::beginProfile(const String& profileName, uint32 groupID) 

    {

#ifdef USE_REMOTERY

        // mask groups

        if ((groupID & mProfileMask) == 0)

            return;

        rmt_BeginCPUSampleDynamic(profileName.c_str(), RMTSF_Aggregate);

#else

        // if the profiler is enabled

        if (!mEnabled)

            return;

        // mask groups

        if ((groupID & mProfileMask) == 0)

            return;

        // empty string is reserved for the root

        // not really fatal anymore, however one shouldn't name one's profile as an empty string anyway.

        assert ((profileName != "") && ("Profile name can't be an empty string"));

        // we only process this profile if isn't disabled

        if (mDisabledProfiles.find(profileName) != mDisabledProfiles.end())

            return;

        // regardless of whether or not we are enabled, we need the application's root profile (ie the first profile started each frame)

        // we need this so bogus profiles don't show up when users enable profiling mid frame

        // so we check

        // this would be an internal error.

        assert (mCurrent);

        // need a timer to profile!

        assert (mTimer && "Timer not set!");

        ProfileInstance*& instance = mCurrent->children[profileName];

        if(instance)

        {   // found existing child.

            // Sanity check.

            assert(instance->name == profileName);

            if(instance->frameNumber != mCurrentFrame)

            {   // new frame, reset stats

                instance->frame.calls = 0;

                instance->frame.frameTime = 0;

                instance->frameNumber = mCurrentFrame;

            }

        }

        else

        {   // new child!

            instance = OGRE_NEW ProfileInstance();

            instance->name = profileName;

            instance->parent = mCurrent;

            instance->hierarchicalLvl = mCurrent->hierarchicalLvl + 1;

        }

        instance->frameNumber = mCurrentFrame;

        mCurrent = instance;

        // we do this at the very end of the function to get the most

        // accurate timing results

        mCurrent->currTime = mTimer->getMicroseconds();

#endif

    }

    //-----------------------------------------------------------------------

    void Profiler::endProfile(const String& profileName, uint32 groupID) 

    {

#ifdef USE_REMOTERY

        // mask groups

        if ((groupID & mProfileMask) == 0)

            return;

        rmt_EndCPUSample();

#else

        if(!mEnabled) 

        {

            // if the profiler received a request to be enabled or disabled

            if(mNewEnableState != mEnabled) 

            {   // note mNewEnableState == true to reach this.

                changeEnableState();

                // NOTE we will be in an 'error' state until the next begin. ie endProfile will likely get invoked using a profileName that was never started.

                // even then, we can't be sure that the next beginProfile will be the true start of a new frame

            }

            return;

        }

        else

        {

            if(mNewEnableState != mEnabled) 

            {   // note mNewEnableState == false to reach this.

                changeEnableState();

                // unwind the hierarchy, should be easy enough

                mCurrent = &mRoot;

                mLast = NULL;

            }

            if(&mRoot == mCurrent && mLast)

            {   // profiler was enabled this frame, but the first subsequent beginProfile was NOT the beinging of a new frame as we had hoped.

                // we have bogus ProfileInstance in our hierarchy, we will need to remove it, then update the overlays so as not to confuse ze user

                for(auto& e : mRoot.children)

                {

                    OGRE_DELETE e.second;

                }

                mRoot.children.clear();

                mLast = NULL;

                processFrameStats();

                displayResults();

            }

        }

        if(&mRoot == mCurrent)

            return;

        // mask groups

        if ((groupID & mProfileMask) == 0)

            return;

        // need a timer to profile!

        assert (mTimer && "Timer not set!");

        // get the end time of this profile

        // we do this as close the beginning of this function as possible

        // to get more accurate timing results

        const ulong endTime = mTimer->getMicroseconds();

        // empty string is reserved for designating an empty parent

        assert ((profileName != "") && ("Profile name can't be an empty string"));

        // we only process this profile if isn't disabled

        // we check the current instance name against the provided profileName as a guard against disabling a profile name /after/ said profile began

        if(mCurrent->name != profileName && mDisabledProfiles.find(profileName) != mDisabledProfiles.end()) 

            return;

        // calculate the elapsed time of this profile

        const ulong timeElapsed = endTime - mCurrent->currTime;

        // update parent's accumulator if it isn't the root

        if (&mRoot != mCurrent->parent) 

        {

            // add this profile's time to the parent's accumlator

            mCurrent->parent->accum += timeElapsed;

        }

        mCurrent->frame.frameTime += timeElapsed;

        ++mCurrent->frame.calls;

        mLast = mCurrent;

        mCurrent = mCurrent->parent;

        if (&mRoot == mCurrent) 

        {

            // the stack is empty and all the profiles have been completed

            // we have reached the end of the frame so process the frame statistics

            // we know that the time elapsed of the main loop is the total time the frame took

            mTotalFrameTime = timeElapsed;

            if(timeElapsed > mMaxTotalFrameTime)

                mMaxTotalFrameTime = timeElapsed;

            // we got all the information we need, so process the profiles

            // for this frame

            processFrameStats();

            // we display everything to the screen

            displayResults();

        }

#endif

    }

    //-----------------------------------------------------------------------

    void Profiler::processFrameStats(ProfileInstance* instance, Real& maxFrameTime)

    {

        // calculate what percentage of frame time this profile took

        const Real framePercentage = (Real) instance->frame.frameTime / (Real) mTotalFrameTime;

        const Real frameTimeMillisecs = (Real) instance->frame.frameTime / 1000.0f;

        // update the profile stats

        instance->history.currentTimePercent = framePercentage;

        instance->history.currentTimeMillisecs = frameTimeMillisecs;

        if(mResetExtents)

        {

            instance->history.totalTimePercent = framePercentage;

            instance->history.totalTimeMillisecs = frameTimeMillisecs;

            instance->history.totalCalls = 1;

        }

        else

        {

            instance->history.totalTimePercent += framePercentage;

            instance->history.totalTimeMillisecs += frameTimeMillisecs;

            instance->history.totalCalls++;

        }

        instance->history.numCallsThisFrame = instance->frame.calls;

        // if we find a new minimum for this profile, update it

        if (frameTimeMillisecs < instance->history.minTimeMillisecs || mResetExtents)

        {

            instance->history.minTimePercent = framePercentage;

            instance->history.minTimeMillisecs = frameTimeMillisecs;

        }

        // if we find a new maximum for this profile, update it

        if (frameTimeMillisecs > instance->history.maxTimeMillisecs || mResetExtents)

        {

            instance->history.maxTimePercent = framePercentage;

            instance->history.maxTimeMillisecs = frameTimeMillisecs;

        }

        if (instance->frame.frameTime > maxFrameTime)

            maxFrameTime = (Real)instance->frame.frameTime;

        for (auto& i : instance->children)

        {

            ProfileInstance* child = i.second;

            // we set the number of times each profile was called per frame to 0

            // because not all profiles are called every frame

            child->history.numCallsThisFrame = 0;

            if(child->frame.calls > 0)

            {

                processFrameStats(child, maxFrameTime);

            }

        }

    }

    //-----------------------------------------------------------------------

    void Profiler::processFrameStats(void) 

    {

        Real maxFrameTime = 0;

        for (auto& i : mRoot.children)

        {

            ProfileInstance* child = i.second;

            // we set the number of times each profile was called per frame to 0

            // because not all profiles are called every frame

            child->history.numCallsThisFrame = 0;

            if(child->frame.calls > 0)

            {

                processFrameStats(child, maxFrameTime);

            }

        }

        // Calculate whether the extents are now so out of date they need regenerating

        if (mCurrentFrame == 0)

            mAverageFrameTime = maxFrameTime;

        else

            mAverageFrameTime = (mAverageFrameTime + maxFrameTime) * 0.5f;

        if ((Real)mMaxTotalFrameTime > mAverageFrameTime * 4)

        {

            mResetExtents = true;

            mMaxTotalFrameTime = (ulong)mAverageFrameTime;

        }

        else

            mResetExtents = false;

    }

    //-----------------------------------------------------------------------

    void Profiler::displayResults() 

    {

        // if its time to update the display

        if (!(mCurrentFrame % mUpdateDisplayFrequency)) 

        {

            // ensure the root won't be culled

            mRoot.frame.calls = 1;

            for(auto& l : mListeners)

                l->displayResults(mRoot, mMaxTotalFrameTime);

        }

        ++mCurrentFrame;

    }

    //-----------------------------------------------------------------------

    bool Profiler::watchForMax(const String& profileName) 

    {

        assert ((profileName != "") && ("Profile name can't be an empty string"));

        return mRoot.watchForMax(profileName);

    }

    //-----------------------------------------------------------------------

    bool ProfileInstance::watchForMax(const String& profileName) 

    {

        for(auto& i : children)

        {

            ProfileInstance* child = i.second;

            if( (child->name == profileName && child->watchForMax()) || child->watchForMax(profileName))

                return true;

        }

        return false;

    }

    //-----------------------------------------------------------------------

    bool Profiler::watchForMin(const String& profileName) 

    {

        assert ((profileName != "") && ("Profile name can't be an empty string"));

        return mRoot.watchForMin(profileName);

    }

    //-----------------------------------------------------------------------

    bool ProfileInstance::watchForMin(const String& profileName) 

    {

        for(auto& i : children)

        {

            ProfileInstance* child = i.second;

            if( (child->name == profileName && child->watchForMin()) || child->watchForMin(profileName))

                return true;

        }

        return false;

    }

    //-----------------------------------------------------------------------

    bool Profiler::watchForLimit(const String& profileName, Real limit, bool greaterThan) 

    {

        assert ((profileName != "") && ("Profile name can't be an empty string"));

        return mRoot.watchForLimit(profileName, limit, greaterThan);

    }

    //-----------------------------------------------------------------------

    bool ProfileInstance::watchForLimit(const String& profileName, Real limit, bool greaterThan) 

    {

        for(auto& i : children)

        {

            ProfileInstance* child = i.second;

            if( (child->name == profileName && child->watchForLimit(limit, greaterThan)) || child->watchForLimit(profileName, limit, greaterThan))

                return true;

        }

        return false;

    }

    //-----------------------------------------------------------------------

    void Profiler::logResults() 

    {

        LogManager::getSingleton().logMessage("----------------------Profiler Results----------------------");

        for(auto& it : mRoot.children)

        {

            it.second->logResults();

        }

        LogManager::getSingleton().logMessage("------------------------------------------------------------");

    }

    //-----------------------------------------------------------------------

    void ProfileInstance::logResults() 

    {

        LogManager::getSingleton().logMessage(StringUtil::format(

            "%*s%s\t| Min %.2f | Max %.2f | Avg %.2f", hierarchicalLvl * 4, "", name.c_str(), history.minTimePercent,

            history.maxTimePercent, history.totalTimePercent / history.totalCalls));

        for(auto& it : children)

        {

            it.second->logResults();

        }

    }

    //-----------------------------------------------------------------------

    void Profiler::reset() 

    {

        mRoot.reset();

        mMaxTotalFrameTime = 0;

    }

    //-----------------------------------------------------------------------

    void ProfileInstance::reset(void)

    {

        history.currentTimePercent = history.maxTimePercent = history.totalTimePercent = 0;

        history.currentTimeMillisecs = history.maxTimeMillisecs = history.totalTimeMillisecs = 0;

        history.numCallsThisFrame = history.totalCalls = 0;

        history.minTimePercent = 1;

        history.minTimeMillisecs = 100000;

        for(auto& it : children)

        {

            it.second->reset();

        }

    }

    //-----------------------------------------------------------------------

    void Profiler::setUpdateDisplayFrequency(uint freq)

    {

        mUpdateDisplayFrequency = freq;

    }

    //-----------------------------------------------------------------------

    uint Profiler::getUpdateDisplayFrequency() const

    {

        return mUpdateDisplayFrequency;

    }

    //-----------------------------------------------------------------------

    void Profiler::addListener(ProfileSessionListener* listener)

    {

        if (std::find(mListeners.begin(), mListeners.end(), listener) == mListeners.end())

            mListeners.push_back(listener);

    }

    //-----------------------------------------------------------------------

    void Profiler::removeListener(ProfileSessionListener* listener)

    {

        TProfileSessionListener::iterator i = std::find(mListeners.begin(), mListeners.end(), listener);

        if (i != mListeners.end())

            mListeners.erase(i);

    }

    //-----------------------------------------------------------------------

}