/*

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

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"

#include "OgreViewport.h"

#include "OgreRenderTargetListener.h"

#include "OgreTimer.h"

namespace Ogre {

    RenderTarget::RenderTarget()

        : mPriority(OGRE_DEFAULT_RT_GROUP)

        , mDepthBufferPoolId(RBP_DEFAULT)

        , mDepthBuffer(0)

        , mActive(true)

        , mAutoUpdate(true)

        , mHwGamma(false)

        , mFSAA(0)

#if OGRE_NO_QUAD_BUFFER_STEREO == 0

    , mStereoEnabled(true)

#else

    , mStereoEnabled(false)

#endif

    {

        mTimer = Root::getSingleton().getTimer();

        resetStatistics();

    }

    RenderTarget::~RenderTarget()

    {

        // make a copy of the list to avoid crashes, the viewport destructor change the list

        ViewportList vlist = mViewportList;

        // Delete viewports

        for (auto & i : vlist)

        {

            fireViewportRemoved(i.second);

            OGRE_DELETE i.second;

        }

        //DepthBuffer keeps track of us, avoid a dangling pointer

        detachDepthBuffer();

        // Write closing message

        LogManager::getSingleton().stream(LML_TRIVIAL)

            << "Render Target '" << mName << "' "

            << "Average FPS: " << mStats.avgFPS << " "

            << "Best FPS: " << mStats.bestFPS << " "

            << "Worst FPS: " << mStats.worstFPS; 

    }

    void RenderTarget::getMetrics(unsigned int& width, unsigned int& height)

    {

        width = mWidth;

        height = mHeight;

    }

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

    void RenderTarget::setDepthBufferPool( uint16 poolId )

    {

        if( mDepthBufferPoolId != poolId )

        {

            mDepthBufferPoolId = poolId;

            detachDepthBuffer();

        }

    }

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

    bool RenderTarget::attachDepthBuffer( DepthBuffer *depthBuffer )

    {

        bool retVal = false;

        if( (retVal = depthBuffer->isCompatible( this )) )

        {

            detachDepthBuffer();

            mDepthBuffer = depthBuffer;

            mDepthBuffer->_notifyRenderTargetAttached( this );

        }

        return retVal;

    }

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

    void RenderTarget::detachDepthBuffer()

    {

        if( mDepthBuffer )

        {

            mDepthBuffer->_notifyRenderTargetDetached( this );

            _detachDepthBuffer();

        }

    }

    void RenderTarget::updateImpl(void)

    {

        _beginUpdate();

        _updateAutoUpdatedViewports(true);

        _endUpdate();

    }

    void RenderTarget::_beginUpdate()

    {

        // notify listeners (pre)

        firePreUpdate();

        mStats.triangleCount = 0;

        mStats.batchCount = 0;

    }

    void RenderTarget::_updateAutoUpdatedViewports(bool updateStatistics)

    {

        // Go through viewports in Z-order

        // Tell each to refresh

        for (const auto& v : mViewportList)

        {

            Viewport* viewport = v.second;

            if(viewport->isAutoUpdated())

            {

                _updateViewport(viewport,updateStatistics);

            }

        }

    }

    void RenderTarget::_endUpdate()

    {

         // notify listeners (post)

        firePostUpdate();

        // Update statistics (always on top)

        updateStats();

    }

    void RenderTarget::_updateViewport(Viewport* viewport, bool updateStatistics)

    {

        assert(viewport->getTarget() == this &&

                "RenderTarget::_updateViewport the requested viewport is "

                "not bound to the rendertarget!");

        fireViewportPreUpdate(viewport);

        viewport->update();

        if(updateStatistics)

        {

            mStats.triangleCount += viewport->_getNumRenderedFaces();

            mStats.batchCount += viewport->_getNumRenderedBatches();

        }

        fireViewportPostUpdate(viewport);

    }

    Viewport* RenderTarget::addViewport(Camera* cam, int ZOrder, FloatRect rect)

    {       

        // Check no existing viewport with this Z-order

        ViewportList::iterator it = mViewportList.find(ZOrder);

        if (it != mViewportList.end())

        {

            StringStream str;

            str << "Can't create another viewport for "

                << mName << " with Z-order " << ZOrder

                << " because a viewport exists with this Z-order already.";

            OGRE_EXCEPT(Exception::ERR_INVALIDPARAMS, str.str(), "RenderTarget::addViewport");

        }

        // Add viewport to list

        // Order based on Z-order

        Viewport* vp = OGRE_NEW Viewport(cam, this, rect, ZOrder);

        mViewportList.emplace(ZOrder, vp);

        fireViewportAdded(vp);

        return vp;

    }

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

    void RenderTarget::removeViewport(int ZOrder)

    {

        ViewportList::iterator it = mViewportList.find(ZOrder);

        if (it != mViewportList.end())

        {

            fireViewportRemoved(it->second);

            OGRE_DELETE (*it).second;

            mViewportList.erase(ZOrder);

        }

    }

    void RenderTarget::removeAllViewports(void)

    {

        // make a copy of the list to avoid crashes, the viewport destructor change the list

        ViewportList vlist = mViewportList;

        for (auto& vl : vlist)

        {

            fireViewportRemoved(vl.second);

            OGRE_DELETE vl.second;

        }

        mViewportList.clear();

    }

    void RenderTarget::resetStatistics(void)

    {

        mStats.avgFPS = 0.0;

        mStats.bestFPS = 0.0;

        mStats.lastFPS = 0.0;

        mStats.worstFPS = 999.0;

        mStats.triangleCount = 0;

        mStats.batchCount = 0;

        mStats.bestFrameTime = 999999;

        mStats.worstFrameTime = 0;

        mStats.vBlankMissCount = -1;

        mLastTime = mTimer->getMilliseconds();

        mLastSecond = mLastTime;

        mFrameCount = 0;

    }

    void RenderTarget::updateStats(void)

    {

        ++mFrameCount;

        unsigned long thisTime = mTimer->getMilliseconds();

        // check frame time

        unsigned long frameTime = thisTime - mLastTime ;

        mLastTime = thisTime ;

        mStats.bestFrameTime = std::min(mStats.bestFrameTime, frameTime);

        mStats.worstFrameTime = std::max(mStats.worstFrameTime, frameTime);

        // check if new second (update only once per second)

        if (thisTime - mLastSecond > 1000) 

        { 

            // new second - not 100% precise

            mStats.lastFPS = (float)mFrameCount / (float)(thisTime - mLastSecond) * 1000.0f;

            if (mStats.avgFPS == 0)

                mStats.avgFPS = mStats.lastFPS;

            else

                mStats.avgFPS = (mStats.avgFPS + mStats.lastFPS) / 2; // not strictly correct, but good enough

            mStats.bestFPS = std::max(mStats.bestFPS, mStats.lastFPS);

            mStats.worstFPS = std::min(mStats.worstFPS, mStats.lastFPS);

            mLastSecond = thisTime ;

            mFrameCount  = 0;

        }

    }

    void RenderTarget::getCustomAttribute(const String& name, void* pData)

    {

        OGRE_EXCEPT(Exception::ERR_INVALIDPARAMS, "Attribute not found. " + name, " RenderTarget::getCustomAttribute");

    }

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

    void RenderTarget::addListener(RenderTargetListener* listener)

    {

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

            mListeners.push_back(listener);

    }

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

    void RenderTarget::insertListener(RenderTargetListener* listener, const unsigned int pos)

    {

        // if the position is larger than the list size we just set the listener at the end of the list

        if (pos > mListeners.size())

            mListeners.push_back(listener);

        else

            mListeners.insert(mListeners.begin() + pos, listener);

    }

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

    void RenderTarget::removeListener(RenderTargetListener* listener)

    {

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

        if (i != mListeners.end())

            mListeners.erase(i);

    }

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

    void RenderTarget::removeAllListeners(void)

    {

        mListeners.clear();

    }

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

    void RenderTarget::firePreUpdate(void)

    {

        RenderTargetEvent evt;

        evt.source = this;

        for(auto& l : mListeners)

        {

            l->preRenderTargetUpdate(evt);

        }

    }

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

    void RenderTarget::firePostUpdate(void)

    {

        RenderTargetEvent evt;

        evt.source = this;

        for(auto& l : mListeners)

        {

            l->postRenderTargetUpdate(evt);

        }

    }

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

    Viewport* RenderTarget::getViewport(unsigned short index)

    {

        assert (index < mViewportList.size() && "Index out of bounds");

        ViewportList::iterator i = mViewportList.begin();

        while (index--)

            ++i;

        return i->second;

    }

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

    Viewport* RenderTarget::getViewportByZOrder(int ZOrder)

    {

        ViewportList::iterator i = mViewportList.find(ZOrder);

        if(i == mViewportList.end())

        {

            OGRE_EXCEPT(Exception::ERR_ITEM_NOT_FOUND,"No viewport with given Z-order: "

                + StringConverter::toString(ZOrder), "RenderTarget::getViewportByZOrder");

        }

        return i->second;

    }

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

    bool RenderTarget::hasViewportWithZOrder(int ZOrder)

    {

        ViewportList::iterator i = mViewportList.find(ZOrder);

        return i != mViewportList.end();

    }

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

    void RenderTarget::fireViewportPreUpdate(Viewport* vp)

    {

        RenderTargetViewportEvent evt;

        evt.source = vp;

        for(auto& l : mListeners)

        {

            l->preViewportUpdate(evt);

        }

    }

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

    void RenderTarget::fireViewportPostUpdate(Viewport* vp)

    {

        RenderTargetViewportEvent evt;

        evt.source = vp;

        for(auto& l : mListeners)

        {

            l->postViewportUpdate(evt);

        }

    }

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

    void RenderTarget::fireViewportAdded(Viewport* vp)

    {

        RenderTargetViewportEvent evt;

        evt.source = vp;

        for(auto& l : mListeners)

        {

            l->viewportAdded(evt);

        }

    }

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

    void RenderTarget::fireViewportRemoved(Viewport* vp)

    {

        RenderTargetViewportEvent evt;

        evt.source = vp;

        // Make a temp copy of the listeners

        // some will want to remove themselves as listeners when they get this

        RenderTargetListenerList tempList = mListeners;

        for(auto& l : tempList)

        {

            l->viewportRemoved(evt);

        }

    }

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

    String RenderTarget::writeContentsToTimestampedFile(const String& filenamePrefix, const String& filenameSuffix)

    {

        auto t = std::time(nullptr);

        auto pTime = std::localtime(&t);

        // use ISO 8601 order

        StringStream oss;

        oss << filenamePrefix

            << std::put_time(pTime, "%Y%m%d_%H%M%S")

            << std::setw(3) << std::setfill('0') << (mTimer->getMilliseconds() % 1000)

            << filenameSuffix;

        String filename = oss.str();

        writeContentsToFile(filename);

        return filename;

    }

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

    void RenderTarget::writeContentsToFile(const String& filename)

    {

        Image img(suggestPixelFormat(), mWidth, mHeight);

        PixelBox pb = img.getPixelBox();

        copyContentsToMemory(pb, pb);

        img.save(filename);

    }

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

    void RenderTarget::_notifyCameraRemoved(const Camera* cam)

    {

        ViewportList::iterator i, iend;

        iend = mViewportList.end();

        for (auto& l : mViewportList)

        {

            Viewport* v = l.second;

            if (v->getCamera() == cam)

            {

                // disable camera link

                v->setCamera(0);

            }

        }

    }

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

    void RenderTarget::update(bool swap)

    {

        GpuEventScope profileScope(mName);

        // call implementation

        updateImpl();

        if (swap)

        {

            // Swap buffers

            swapBuffers();

        }

    }

}