//-----------------------------------------------------------------------------
// Copyright (c) 2012 GarageGames, LLC
//
// 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 "platform/platform.h"
#include "T3D/physics/physx3/px3World.h"

#include "T3D/physics/physx3/px3.h"
#include "T3D/physics/physx3/px3Plugin.h"
#include "T3D/physics/physx3/px3Casts.h"
#include "T3D/physics/physx3/px3Stream.h"
#include "T3D/physics/physicsUserData.h"

#include "console/engineAPI.h"
#include "core/stream/bitStream.h"
#include "platform/profiler.h"
#include "sim/netConnection.h"
#include "console/console.h"
#include "console/consoleTypes.h"
#include "core/util/safeDelete.h"
#include "collision/collision.h"
#include "T3D/gameBase/gameProcess.h"
#include "gfx/sim/debugDraw.h"
#include "gfx/primBuilder.h"

physx::PxPhysics* gPhysics3SDK = NULL;
physx::PxCooking* Px3World::smCooking = NULL;
physx::PxFoundation* Px3World::smFoundation = NULL;
physx::PxDefaultCpuDispatcher* Px3World::smCpuDispatcher = NULL;
#ifndef TORQUE_OS_MAC
physx::PxCudaContextManager* Px3World::smCudaContextManager = NULL;
#endif
Px3ConsoleStream* Px3World::smErrorCallback = NULL;
physx::PxPvd* Px3World::smPvdConnection = NULL;
physx::PxPvdTransport* Px3World::smPvdTransport = NULL;
physx::PxDefaultAllocator Px3World::smMemoryAlloc;

Px3World::Px3World() :
   mScene( NULL ),
   mIsEnabled( false ),
   mIsSimulating( false ),
   mIsServer( false ),
   mIsSceneLocked( false ),
   mTickCount( 0 ),
   mProcessList( NULL ),
   mEditorTimeScale( 1.0f ),
   mErrorReport( false ),
   mControllerManager(NULL),
   mRenderBuffer(NULL),
   mAccumulator( 0 )
{
}

Px3World::~Px3World()
{
}

physx::PxCooking *Px3World::getCooking()
{
   return smCooking;
}

bool Px3World::restartSDK( bool destroyOnly, Px3World *clientWorld, Px3World *serverWorld)
{
   // If either the client or the server still exist
   // then we cannot reset the SDK.
   if ( clientWorld || serverWorld )
      return false;
#ifndef TORQUE_OS_MAC
   SafeReleasePhysx(smCudaContextManager);
#endif
   SafeReleasePhysx(smCpuDispatcher);
   SafeReleasePhysx(smCooking);
   smGpuEnabled = false;

   // Destroy the existing SDK.
   if ( gPhysics3SDK )
   {
      PxCloseExtensions();
      SafeReleasePhysx(gPhysics3SDK);
   }

   SafeReleasePhysx(smPvdConnection);
   SafeReleasePhysx(smPvdTransport);

   SAFE_DELETE(smErrorCallback);
   SafeReleasePhysx(smFoundation);

   // If we're not supposed to restart... return.
   if ( destroyOnly )
      return true;

   bool memTrack = false;
 #ifdef TORQUE_DEBUG
   memTrack = false;
 #endif
   
   smErrorCallback  = new Px3ConsoleStream;
   smFoundation = PxCreateFoundation(PX_FOUNDATION_VERSION, smMemoryAlloc, *smErrorCallback);
   smPvdConnection = PxCreatePvd(*smFoundation);
   gPhysics3SDK = PxCreatePhysics(PX_PHYSICS_VERSION, *smFoundation, physx::PxTolerancesScale(),memTrack, smPvdConnection);

   if ( !gPhysics3SDK )
   {
      Con::errorf( "PhysX3 failed to initialize!" );
      Platform::messageBox( Con::getVariable( "$appName" ), avar("PhysX3 could not be started!\r\n"), MBOk, MIStop );
      Platform::forceShutdown( -1 );
      
      // We shouldn't get here, but this shuts up
      // source diagnostic tools.
      return false;
   }

   if(!PxInitExtensions(*gPhysics3SDK, smPvdConnection))
   {
      Con::errorf( "PhysX3 failed to initialize extensions!" );
      Platform::messageBox(   Con::getVariable( "$appName" ), avar("PhysX3 could not be started!\r\n"), MBOk, MIStop );
      Platform::forceShutdown( -1 );
      return false;
   }
//no gpu support on macOS
#ifndef TORQUE_OS_MAC
   //check if we are allowed to use gpu acceleration
   if (PhysicsPlugin::gpuAccelerationAllowed())
   {
      // attempt to create a cuda context manager - only works on nvidia gpu (SM 3.0+ i.e kepler or better)
      if (!smCpuDispatcher)
      {
         //check we have capable gpu, -1 means none found
         S32 suggestedGpu = PxGetSuggestedCudaDeviceOrdinal(*smErrorCallback);
         if (suggestedGpu != -1)
         {
            physx::PxCudaContextManagerDesc cudaContextManagerDesc;
            smCudaContextManager = PxCreateCudaContextManager(*smFoundation, cudaContextManagerDesc);
            if (smCudaContextManager)
               smGpuEnabled = true;
         }
      }
   }
#endif

   //cpu dispatcher
   if (!smCpuDispatcher)
      smCpuDispatcher = physx::PxDefaultCpuDispatcherCreate(PHYSICSMGR->getThreadCount());

   physx::PxCookingParams params = physx::PxCookingParams(physx::PxTolerancesScale());
   params.meshWeldTolerance = 0.001f;
   params.meshPreprocessParams = physx::PxMeshPreprocessingFlags(physx::PxMeshPreprocessingFlag::eWELD_VERTICES);
#ifndef TORQUE_OS_MAC
   if(smGpuEnabled)
      params.buildGPUData = true;
#endif

   smCooking = PxCreateCooking(PX_PHYSICS_VERSION, *smFoundation, params);
   if(!smCooking)
   {
      Con::errorf( "PhysX3 failed to initialize cooking!" );
      Platform::messageBox( Con::getVariable( "$appName" ), avar("PhysX3 could not be started!\r\n"), MBOk, MIStop );
      Platform::forceShutdown( -1 );      
      return false;
   }

   //TODO: enable/disable this from script
#ifdef TORQUE_DEBUG
   if(!smPvdTransport)
      smPvdTransport = physx::PxDefaultPvdSocketTransportCreate("localhost", 5425, 100);

   smPvdConnection->connect(*smPvdTransport, physx::PxPvdInstrumentationFlag::eALL);
#endif

   //use legacy heightfield
   //TODO: new method causing crashes on collision in debug build (unified HeightFields)
   PxRegisterLegacyHeightFields(*gPhysics3SDK);

   return true;
}

void Px3World::destroyWorld()
{
   getPhysicsResults();

   // Release the tick processing signals.
   if ( mProcessList )
   {
      mProcessList->preTickSignal().remove( this, &Px3World::getPhysicsResults );
      mProcessList->postTickSignal().remove( this, &Px3World::tickPhysics );
      mProcessList = NULL;
   }

   SafeReleasePhysx(mControllerManager);
   // Destroy the scene.
   SafeReleasePhysx(mScene);
}

bool Px3World::initWorld( bool isServer, ProcessList *processList )
{
   if ( !gPhysics3SDK )
   {
      Con::errorf( "Physx3World::init - PhysXSDK not initialized!" );
      return false;
   }

   mIsServer = isServer;
	
   physx::PxSceneDesc sceneDesc(gPhysics3SDK->getTolerancesScale());

   sceneDesc.gravity = px3Cast<physx::PxVec3>(mGravity);
   sceneDesc.userData = this;
 
   sceneDesc.cpuDispatcher = smCpuDispatcher;
   Con::printf("PhysX3 using Cpu: %d workers", smCpuDispatcher->getWorkerCount());

#ifndef TORQUE_OS_MAC
   if (smGpuEnabled)
   {
      sceneDesc.flags |= physx::PxSceneFlag::eENABLE_GPU_DYNAMICS;
      sceneDesc.flags |= physx::PxSceneFlag::eENABLE_PCM;
      sceneDesc.broadPhaseType = physx::PxBroadPhaseType::eGPU;
      sceneDesc.gpuDispatcher = smCudaContextManager->getGpuDispatcher();
      Con::printf("PhysX3 using Gpu: %s", smCudaContextManager->getDeviceName());
   }
#endif

   sceneDesc.flags |= physx::PxSceneFlag::eENABLE_CCD;
   sceneDesc.flags |= physx::PxSceneFlag::eENABLE_ACTIVETRANSFORMS;
   sceneDesc.filterShader  = physx::PxDefaultSimulationFilterShader;

	mScene = gPhysics3SDK->createScene(sceneDesc);

   mRenderBuffer = const_cast<physx::PxRenderBuffer*>(&mScene->getRenderBuffer());

   physx::PxDominanceGroupPair debrisDominance( 0.0f, 1.0f );
   mScene->setDominanceGroupPair(0,31,debrisDominance);

   mControllerManager = PxCreateControllerManager(*mScene);

   AssertFatal( processList, "Px3World::init() - We need a process list to create the world!" );
   mProcessList = processList;
   mProcessList->preTickSignal().notify( this, &Px3World::getPhysicsResults );
   mProcessList->postTickSignal().notify( this, &Px3World::tickPhysics, 1000.0f );

   return true;
}
// Most of this borrowed from bullet physics library, see btDiscreteDynamicsWorld.cpp
bool Px3World::_simulate(const F32 dt)
{
   S32 numSimulationSubSteps = 0;
   //fixed timestep with interpolation
   mAccumulator += dt;
   if (mAccumulator >= smPhysicsStepTime)
   {
      numSimulationSubSteps = S32(mAccumulator / smPhysicsStepTime);
      mAccumulator -= numSimulationSubSteps * smPhysicsStepTime;
   }
   if (numSimulationSubSteps)
   {
      //clamp the number of substeps, to prevent simulation grinding spiralling down to a halt
      S32 clampedSimulationSteps = (numSimulationSubSteps > smPhysicsMaxSubSteps) ? smPhysicsMaxSubSteps : numSimulationSubSteps;
		
      for (S32 i=0;i<clampedSimulationSteps;i++)
      {
         if(i > 0)
            mScene->fetchResults(true);
         mScene->simulate(smPhysicsStepTime);
      }
   }
	
   mIsSimulating = true;

   return true;
}

void Px3World::tickPhysics( U32 elapsedMs )
{
   if ( !mScene || !mIsEnabled )
      return;

   // Did we forget to call getPhysicsResults somewhere?
   AssertFatal( !mIsSimulating, "PhysX3World::tickPhysics() - Already simulating!" );

   // The elapsed time should be non-zero and 
   // a multiple of TickMs!
   AssertFatal(   elapsedMs != 0 &&
                  ( elapsedMs % TickMs ) == 0 , "PhysX3World::tickPhysics() - Got bad elapsed time!" );

   PROFILE_SCOPE(Px3World_TickPhysics);

   // Convert it to seconds.
   const F32 elapsedSec = (F32)elapsedMs * 0.001f;
   mIsSimulating = _simulate(elapsedSec * mEditorTimeScale);

   //Con::printf( "%s PhysX3World::tickPhysics!", mIsServer ? "Client" : "Server" );
}

void Px3World::getPhysicsResults()
{
   if ( !mScene || !mIsSimulating ) 
      return;

   PROFILE_SCOPE(Px3World_GetPhysicsResults);

   // Get results from scene.
   mScene->fetchResults(true);
   mIsSimulating = false;
   mTickCount++;
}

void Px3World::lockScenes()
{
   Px3World *world = dynamic_cast<Px3World*>(PHYSICSMGR->getWorld("server"));

   if (world)
      world->lockScene();

   world = dynamic_cast<Px3World*>(PHYSICSMGR->getWorld("client"));

   if (world)
      world->lockScene();
}

void Px3World::unlockScenes()
{
   Px3World *world = dynamic_cast<Px3World*>(PHYSICSMGR->getWorld("server"));

   if (world)
      world->unlockScene();

   world = dynamic_cast<Px3World*>(PHYSICSMGR->getWorld("client"));

   if (world)
      world->unlockScene();
}

void Px3World::lockScene()
{
   if (!mScene)
      return;

   if (mIsSceneLocked)
   {
      Con::printf("Px3World: Attempting to lock a scene that is already locked.");
      return;
   }

   mScene->lockWrite();
   mIsSceneLocked = true;
}

void Px3World::unlockScene()
{
   if (!mScene)
      return;

   if (!mIsSceneLocked)
   {
      Con::printf("Px3World: Attempting to unlock a scene that is not locked.");
      return;
   }

   mScene->unlockWrite();
   mIsSceneLocked = false;
}

bool Px3World::castRay( const Point3F &startPnt, const Point3F &endPnt, RayInfo *ri, const Point3F &impulse )
{    
   physx::PxVec3 orig = px3Cast<physx::PxVec3>( startPnt );
   physx::PxVec3 dir = px3Cast<physx::PxVec3>( endPnt - startPnt );
   physx::PxF32 maxDist = dir.magnitude();
   dir.normalize();

   U32 groups = 0xffffffff;
   groups &= ~( PX3_TRIGGER ); // No trigger shapes!

   physx::PxHitFlags outFlags(physx::PxHitFlag::eDISTANCE | physx::PxHitFlag::ePOSITION | physx::PxHitFlag::eNORMAL);
   physx::PxQueryFilterData filterData(physx::PxQueryFlag::eSTATIC|physx::PxQueryFlag::eDYNAMIC);
   filterData.data.word0 = groups;
   physx::PxRaycastBuffer buf;

   if(!mScene->raycast(orig,dir,maxDist,buf,outFlags,filterData))
      return false;
   if(!buf.hasBlock)
      return false;

   const physx::PxRaycastHit hit = buf.block;
   physx::PxRigidActor *actor = hit.actor;
   PhysicsUserData *userData = PhysicsUserData::cast( actor->userData );

   if ( ri )
   {
      ri->object = ( userData != NULL ) ? userData->getObject() : NULL;
      
      if ( ri->object == NULL )

      ri->distance = hit.distance;
      ri->normal = px3Cast<Point3F>( hit.normal );
      ri->point = px3Cast<Point3F>( hit.position );
      ri->t = maxDist / hit.distance;
   }

   if ( impulse.isZero() ||
        !actor->is<physx::PxRigidDynamic>() ||
        actor->is<physx::PxRigidDynamic>()->getRigidBodyFlags() & physx::PxRigidBodyFlag::eKINEMATIC )
      return true;
  
   physx::PxRigidBody *body = actor->is<physx::PxRigidBody>();
   physx::PxVec3 force = px3Cast<physx::PxVec3>( impulse );
   physx::PxRigidBodyExt::addForceAtPos(*body,force,hit.position,physx::PxForceMode::eIMPULSE);

   return true;
}

PhysicsBody* Px3World::castRay( const Point3F &start, const Point3F &end, U32 bodyTypes )
{
   physx::PxVec3 orig = px3Cast<physx::PxVec3>( start );
   physx::PxVec3 dir = px3Cast<physx::PxVec3>( end - start );
   physx::PxF32 maxDist = dir.magnitude();
   dir.normalize();

   U32 groups = 0xFFFFFFFF;
   if ( !( bodyTypes & BT_Player ) )
      groups &= ~( PX3_PLAYER );

   // TODO: For now always skip triggers and debris,
   // but we should consider how game specifc this API
   // should be in the future.
   groups &= ~( PX3_TRIGGER ); // triggers
   groups &= ~( PX3_DEBRIS ); // debris

   physx::PxHitFlags outFlags(physx::PxHitFlag::eDISTANCE | physx::PxHitFlag::ePOSITION | physx::PxHitFlag::eNORMAL);
   physx::PxQueryFilterData filterData;
   if(bodyTypes & BT_Static)
      filterData.flags |= physx::PxQueryFlag::eSTATIC;
   if(bodyTypes & BT_Dynamic)
      filterData.flags |= physx::PxQueryFlag::eDYNAMIC;

   filterData.data.word0 = groups;
   physx::PxRaycastBuffer buf;  

   if( !mScene->raycast(orig,dir,maxDist,buf,outFlags,filterData) )
      return NULL;
   if(!buf.hasBlock)
      return NULL;

   physx::PxRigidActor *actor = buf.block.actor;
   PhysicsUserData *userData = PhysicsUserData::cast( actor->userData );
   if( !userData )
      return NULL;

   return userData->getBody();
}

void Px3World::explosion( const Point3F &pos, F32 radius, F32 forceMagnitude )
{
   physx::PxVec3 nxPos = px3Cast<physx::PxVec3>( pos );
   const physx::PxU32 bufferSize = 10;
   physx::PxSphereGeometry worldSphere(radius);
   physx::PxTransform pose(nxPos);
   physx::PxOverlapBufferN<bufferSize> buffer;
  
   if(!mScene->overlap(worldSphere,pose,buffer))
      return;

   for ( physx::PxU32 i = 0; i < buffer.nbTouches; i++ )
   {
      physx::PxRigidActor *actor = buffer.touches[i].actor;
      
      bool dynamic = actor->is<physx::PxRigidDynamic>();
      
      if ( !dynamic )
         continue;

      bool kinematic = actor->is<physx::PxRigidDynamic>()->getRigidBodyFlags() & physx::PxRigidBodyFlag::eKINEMATIC;
      
      if ( kinematic )
         continue;

      physx::PxVec3 force = actor->getGlobalPose().p - nxPos;
      force.normalize();
      force *= forceMagnitude;

      physx::PxRigidBody *body = actor->is<physx::PxRigidBody>();
      physx::PxRigidBodyExt::addForceAtPos(*body,force,nxPos,physx::PxForceMode::eIMPULSE);
   }
}

void Px3World::setEnabled( bool enabled )
{
   mIsEnabled = enabled;

   if ( !mIsEnabled )
      getPhysicsResults();
}

physx::PxController* Px3World::createController( physx::PxControllerDesc &desc )
{
   if ( !mScene )
      return NULL;

   physx::PxController* pController = mControllerManager->createController(desc);
   AssertFatal( pController, "Px3World::createController - Got a null!" );
   return pController;
}

static ColorI getDebugColor( physx::PxU32 packed )
{
   ColorI col;
   col.blue = (packed)&0xff;
   col.green = (packed>>8)&0xff;
   col.red = (packed>>16)&0xff;
   col.alpha = 255;

   return col;
}

void Px3World::onDebugDraw( const SceneRenderState *state )
{
   if ( !mScene || !mRenderBuffer)
      return;

   mScene->setVisualizationParameter(physx::PxVisualizationParameter::eSCALE,1.0f);
   mScene->setVisualizationParameter(physx::PxVisualizationParameter::eBODY_AXES,1.0f);
   mScene->setVisualizationParameter(physx::PxVisualizationParameter::eCOLLISION_SHAPES,1.0f);

   // Render points
   {
      physx::PxU32 numPoints = mRenderBuffer->getNbPoints();
      const physx::PxDebugPoint *points = mRenderBuffer->getPoints();

      PrimBuild::begin( GFXPointList, numPoints );
      
      while ( numPoints-- )
      {
         PrimBuild::color( getDebugColor(points->color) );
         PrimBuild::vertex3fv(px3Cast<Point3F>(points->pos));
         points++;
      }

      PrimBuild::end();
   }

   // Render lines
   {
      physx::PxU32 numLines = mRenderBuffer->getNbLines();
      const physx::PxDebugLine *lines = mRenderBuffer->getLines();

      PrimBuild::begin( GFXLineList, numLines * 2 );

      while ( numLines-- )
      {
         PrimBuild::color( getDebugColor( lines->color0 ) );
         PrimBuild::vertex3fv( px3Cast<Point3F>(lines->pos0));
         PrimBuild::color( getDebugColor( lines->color1 ) );
         PrimBuild::vertex3fv( px3Cast<Point3F>(lines->pos1));
         lines++;
      }

      PrimBuild::end();
   }

   // Render triangles
   {
      physx::PxU32 numTris = mRenderBuffer->getNbTriangles();
      const physx::PxDebugTriangle *triangles = mRenderBuffer->getTriangles();

      PrimBuild::begin( GFXTriangleList, numTris * 3 );
      
      while ( numTris-- )
      {
         PrimBuild::color( getDebugColor( triangles->color0 ) );
         PrimBuild::vertex3fv( px3Cast<Point3F>(triangles->pos0) );
         PrimBuild::color( getDebugColor( triangles->color1 ) );
         PrimBuild::vertex3fv( px3Cast<Point3F>(triangles->pos1));
         PrimBuild::color( getDebugColor( triangles->color2 ) );
         PrimBuild::vertex3fv( px3Cast<Point3F>(triangles->pos2) );
         triangles++;
      }

      PrimBuild::end();
   }

}