/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/

This software is provided 'as-is', without any express or implied warranty.
In no event will the authors be held liable for any damages arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it freely,
subject to the following restrictions:

1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/



#include "OdeConstraintSolver.h"

#include "BulletCollision/NarrowPhaseCollision/btPersistentManifold.h"
#include "BulletDynamics/Dynamics/btRigidBody.h"
#include "BulletDynamics/ConstraintSolver/btContactConstraint.h"
#include "BulletDynamics/ConstraintSolver/btSolve2LinearConstraint.h"
#include "BulletDynamics/ConstraintSolver/btContactSolverInfo.h"
#include "OdeJoint.h"
#include "OdeContactJoint.h"
#include "OdeTypedJoint.h"
#include "OdeSolverBody.h"
#include <new.h>
#include "LinearMath/btQuickprof.h"

#include "LinearMath/btIDebugDraw.h"

#define USE_SOR_SOLVER

#include "SorLcp.h"

#include <math.h>
#include <float.h>//FLT_MAX
#ifdef WIN32
#include <memory.h>
#endif
#include <string.h>
#include <stdio.h>

#if defined (WIN32)
#include <malloc.h>
#else
#if defined (__FreeBSD__)
#include <stdlib.h>
#else
#include <alloca.h>
#endif
#endif

class BU_Joint;

//see below
//to bridge with ODE quickstep, we make a temp copy of the rigidbodies in each simultion island


OdeConstraintSolver::OdeConstraintSolver():
        m_cfm(0.f),//1e-5f),
        m_erp(0.4f)
{
}


//iterative lcp and penalty method
btScalar OdeConstraintSolver::solveGroup(btCollisionObject** bodies,int numBulletBodies,btPersistentManifold** manifoldPtr, int numManifolds,btTypedConstraint** constraints,int numConstraints,const btContactSolverInfo& infoGlobal,btIDebugDraw* debugDrawer,btStackAlloc* stackAlloc,btDispatcher* dispatcher)
{
    BEGIN_PROFILE("prepareConstraints");

    m_CurBody = 0;
    m_CurJoint = 0;
    m_CurTypedJoint = 0;

	int max_contacts = 0; /// should be 4 //Remotion
	for (int j=0;j<numManifolds;j++){
		btPersistentManifold* manifold = manifoldPtr[j];
		if (manifold->getNumContacts() > max_contacts)  max_contacts = manifold->getNumContacts();
	}
	//if(max_contacts > 4)
	//	printf(" max_contacts > 4");

	int numBodies = 0;
	m_odeBodies.clear();
	m_odeBodies.reserve(numBulletBodies + 1); //???
	// OdeSolverBody* odeBodies [ODE_MAX_SOLVER_BODIES];

    int numJoints = 0;
	m_joints.clear();
	m_joints.reserve(numManifolds * max_contacts + 4 + numConstraints + 1); //???
   // BU_Joint* joints [ODE_MAX_SOLVER_JOINTS*2];

	m_SolverBodyArray.resize(numBulletBodies + 1);
	m_JointArray.resize(numManifolds * max_contacts + 4);
	m_TypedJointArray.resize(numConstraints + 1);


	//capture contacts
	int j;
	int body0=-1,body1=-1;
    for (j=0;j<numManifolds;j++)
    {
        btPersistentManifold* manifold = manifoldPtr[j];
        if (manifold->getNumContacts() > 0)
        {
            body0 = ConvertBody((btRigidBody*)manifold->getBody0(),m_odeBodies,numBodies);
            body1 = ConvertBody((btRigidBody*)manifold->getBody1(),m_odeBodies,numBodies);
            ConvertConstraint(manifold,m_joints,numJoints,m_odeBodies,body0,body1,debugDrawer);
        }
    }

    //capture constraints
    for (j=0;j<numConstraints;j++)
    {
    	btTypedConstraint * typedconstraint = constraints[j];
		body0 = ConvertBody((btRigidBody*)&typedconstraint->getRigidBodyA(),m_odeBodies,numBodies);
		body1 = ConvertBody((btRigidBody*)&typedconstraint->getRigidBodyB(),m_odeBodies,numBodies);
		ConvertTypedConstraint(typedconstraint,m_joints,numJoints,m_odeBodies,body0,body1,debugDrawer);
    }
	//if(numBodies > numBulletBodies) 
	//	printf(" numBodies > numBulletBodies");
	//if(numJoints > numManifolds * 4 + numConstraints) 
	//	printf(" numJoints > numManifolds * 4 + numConstraints");


    END_PROFILE("prepareConstraints");
    BEGIN_PROFILE("solveConstraints");
    m_SorLcpSolver.SolveInternal1(m_cfm,m_erp,m_odeBodies,numBodies,m_joints,numJoints,infoGlobal,stackAlloc); ///do

    //write back resulting velocities
    for (int i=0;i<numBodies;i++)
    {
        if (m_odeBodies[i]->m_invMass)
        {
            m_odeBodies[i]->m_originalBody->setLinearVelocity(m_odeBodies[i]->m_linearVelocity);
            m_odeBodies[i]->m_originalBody->setAngularVelocity(m_odeBodies[i]->m_angularVelocity);
        }
    }
    END_PROFILE("solveConstraints");


	/// Remotion, just free all this here
	m_odeBodies.clear();
	m_joints.clear();

	m_SolverBodyArray.clear();
	m_JointArray.clear();
	m_TypedJointArray.clear();

    return 0.f;

}

/////////////////////////////////////////////////////////////////////////////////


typedef btScalar dQuaternion[4];
#define _R(i,j) R[(i)*4+(j)]

void dRfromQ1 (dMatrix3 R, const dQuaternion q)
{
    // q = (s,vx,vy,vz)
    btScalar qq1 = 2.f*q[1]*q[1];
    btScalar qq2 = 2.f*q[2]*q[2];
    btScalar qq3 = 2.f*q[3]*q[3];
    _R(0,0) = 1.f - qq2 - qq3;
    _R(0,1) = 2*(q[1]*q[2] - q[0]*q[3]);
    _R(0,2) = 2*(q[1]*q[3] + q[0]*q[2]);
    _R(0,3) = 0.f;

    _R(1,0) = 2*(q[1]*q[2] + q[0]*q[3]);
    _R(1,1) = 1.f - qq1 - qq3;
    _R(1,2) = 2*(q[2]*q[3] - q[0]*q[1]);
    _R(1,3) = 0.f;

    _R(2,0) = 2*(q[1]*q[3] - q[0]*q[2]);
    _R(2,1) = 2*(q[2]*q[3] + q[0]*q[1]);
    _R(2,2) = 1.f - qq1 - qq2;
    _R(2,3) = 0.f;

}



//int OdeConstraintSolver::ConvertBody(btRigidBody* orgBody,OdeSolverBody** bodies,int& numBodies)
int OdeConstraintSolver::ConvertBody(btRigidBody* orgBody,btAlignedObjectArray< OdeSolverBody*> &bodies,int& numBodies)
{
    assert(orgBody);
    if (!orgBody || (orgBody->getInvMass() == 0.f) )
    {
        return -1;
    }

    if (orgBody->getCompanionId()>=0)
    {
        return orgBody->getCompanionId();
    }
    //first try to find
    int i,j;

    //if not found, create a new body
   // OdeSolverBody* body = bodies[numBodies] = &gSolverBodyArray[numBodies];
	OdeSolverBody* body = &m_SolverBodyArray[numBodies];
	bodies.push_back(body); // Remotion 10.10.07: 

    orgBody->setCompanionId(numBodies);

    numBodies++;

    body->m_originalBody = orgBody;

    body->m_facc.setValue(0,0,0,0);
    body->m_tacc.setValue(0,0,0,0);

    body->m_linearVelocity = orgBody->getLinearVelocity();
    body->m_angularVelocity = orgBody->getAngularVelocity();
    body->m_invMass = orgBody->getInvMass();
    body->m_centerOfMassPosition = orgBody->getCenterOfMassPosition();
    body->m_friction = orgBody->getFriction();

    //are the indices the same ?
    for (i=0;i<4;i++)
    {
        for ( j=0;j<3;j++)
        {
            body->m_invI[i+4*j] = 0.f;
            body->m_I[i+4*j] = 0.f;
        }
    }
    body->m_invI[0+4*0] = 	orgBody->getInvInertiaDiagLocal().x();
    body->m_invI[1+4*1] = 	orgBody->getInvInertiaDiagLocal().y();
    body->m_invI[2+4*2] = 	orgBody->getInvInertiaDiagLocal().z();

    body->m_I[0+0*4] = 1.f/orgBody->getInvInertiaDiagLocal().x();
    body->m_I[1+1*4] = 1.f/orgBody->getInvInertiaDiagLocal().y();
    body->m_I[2+2*4] = 1.f/orgBody->getInvInertiaDiagLocal().z();




    dQuaternion q;

    q[1] = orgBody->getOrientation().x();
    q[2] = orgBody->getOrientation().y();
    q[3] = orgBody->getOrientation().z();
    q[0] = orgBody->getOrientation().w();

    dRfromQ1(body->m_R,q);

    return numBodies-1;
}









void OdeConstraintSolver::ConvertConstraint(btPersistentManifold* manifold,
											btAlignedObjectArray<BU_Joint*> &joints,int& numJoints,
											const btAlignedObjectArray< OdeSolverBody*> &bodies,
											int _bodyId0,int _bodyId1,btIDebugDraw* debugDrawer)
{


    manifold->refreshContactPoints(((btRigidBody*)manifold->getBody0())->getCenterOfMassTransform(),
                                   ((btRigidBody*)manifold->getBody1())->getCenterOfMassTransform());

    int bodyId0 = _bodyId0,bodyId1 = _bodyId1;

    int i,numContacts = manifold->getNumContacts();

    bool swapBodies = (bodyId0 < 0);


    OdeSolverBody* body0,*body1;

    if (swapBodies)
    {
        bodyId0 = _bodyId1;
        bodyId1 = _bodyId0;

        body0 = bodyId0>=0 ? bodies[bodyId0] : 0;//(btRigidBody*)manifold->getBody1();
        body1 = bodyId1>=0 ? bodies[bodyId1] : 0;//(btRigidBody*)manifold->getBody0();

    }
    else
    {
        body0 = bodyId0>=0 ? bodies[bodyId0] : 0;//(btRigidBody*)manifold->getBody0();
        body1 = bodyId1>=0 ? bodies[bodyId1] : 0;//(btRigidBody*)manifold->getBody1();
    }

    assert(bodyId0 >= 0);

    btVector3 color(0,1,0);
    for (i=0;i<numContacts;i++)
    {

        if (debugDrawer)
        {
            const btManifoldPoint& cp = manifold->getContactPoint(i);

            debugDrawer->drawContactPoint(
                cp.m_positionWorldOnB,
                cp.m_normalWorldOnB,
                cp.getDistance(),
                cp.getLifeTime(),
                color);

        }
        //assert (m_CurJoint < ODE_MAX_SOLVER_JOINTS);

//		if (manifold->getContactPoint(i).getDistance() < 0.0f)
        {

            ContactJoint* cont = new (&m_JointArray[m_CurJoint++]) ContactJoint( manifold ,i, swapBodies,body0,body1);
            //ContactJoint* cont = new (&gJointArray[m_CurJoint++]) ContactJoint( manifold ,i, swapBodies,body0,body1);

            cont->node[0].joint = cont;
            cont->node[0].body = bodyId0 >= 0 ? bodies[bodyId0] : 0;

            cont->node[1].joint = cont;
            cont->node[1].body = bodyId1 >= 0 ? bodies[bodyId1] : 0;

           // joints[numJoints++] = cont;
			joints.push_back(cont); // Remotion 10.10.07: 
			numJoints++;

            for (int i=0;i<6;i++)
                cont->lambda[i] = 0.f;

            cont->flags = 0;
        }
    }

    //create a new contact constraint
}

void OdeConstraintSolver::ConvertTypedConstraint(
					btTypedConstraint * constraint,
					btAlignedObjectArray<BU_Joint*> &joints,int& numJoints,
					const btAlignedObjectArray< OdeSolverBody*> &bodies,int _bodyId0,int _bodyId1,btIDebugDraw* debugDrawer)
{

    int bodyId0 = _bodyId0,bodyId1 = _bodyId1;
    bool swapBodies = (bodyId0 < 0);


    OdeSolverBody* body0,*body1;

    if (swapBodies)
    {
        bodyId0 = _bodyId1;
        bodyId1 = _bodyId0;

        body0 = bodyId0>=0 ? bodies[bodyId0] : 0;//(btRigidBody*)manifold->getBody1();
        body1 = bodyId1>=0 ? bodies[bodyId1] : 0;//(btRigidBody*)manifold->getBody0();

    }
    else
    {
        body0 = bodyId0>=0 ? bodies[bodyId0] : 0;//(btRigidBody*)manifold->getBody0();
        body1 = bodyId1>=0 ? bodies[bodyId1] : 0;//(btRigidBody*)manifold->getBody1();
    }

    assert(bodyId0 >= 0);


	//assert (m_CurTypedJoint < ODE_MAX_SOLVER_JOINTS);


	OdeTypedJoint * cont = NULL;

	// Determine constraint type
	int joint_type = constraint->getConstraintType();
	switch(joint_type)
	{
	case POINT2POINT_CONSTRAINT_TYPE:
	case D6_CONSTRAINT_TYPE:
		cont = new (&m_TypedJointArray[m_CurTypedJoint ++]) OdeTypedJoint(constraint,0, swapBodies,body0,body1);
		//cont = new (&gTypedJointArray[m_CurTypedJoint ++]) OdeTypedJoint(constraint,0, swapBodies,body0,body1);
		break;

	};

	if(cont)
	{
		cont->node[0].joint = cont;
		cont->node[0].body = bodyId0 >= 0 ? bodies[bodyId0] : 0;

		cont->node[1].joint = cont;
		cont->node[1].body = bodyId1 >= 0 ? bodies[bodyId1] : 0;

		// joints[numJoints++] = cont;
		joints.push_back(cont); // Remotion 10.10.07: 
		numJoints++;

		for (int i=0;i<6;i++)
			cont->lambda[i] = 0.f;

		cont->flags = 0;
	}

}