/*=========================================================================

   Library: iMSTK

   Copyright (c) Kitware, Inc. & Center for Modeling, Simulation,
   & Imaging in Medicine, Rensselaer Polytechnic Institute.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0.txt

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

=========================================================================*/

#pragma once

#include "imstkMath.h"
#include "imstkInternalForceModelTypes.h"

#ifdef WIN32
#pragma warning( push )
#pragma warning( disable : 4458 )
#pragma warning( disable : 4100 )
#endif
#include <forceModel.h>
#ifdef WIN32
#pragma warning( pop )
#endif

namespace imstk
{
///
/// \class InternalForceModel
///
/// \brief Base class for internal force model within the following context
///
///
class InternalForceModel
{
public:
    InternalForceModel() = default;
    virtual ~InternalForceModel() = default;

    ///
    /// \brief Compute internal force \p internalForce at state \p u
    ///
    virtual void getInternalForce(const Vectord& u, Vectord& internalForce) = 0;

    ///
    /// \brief Compute stiffness matrix \p tangentStiffnessMatrix at state \u
    ///
    virtual void getTangentStiffnessMatrix(const Vectord& u, SparseMatrixd& tangentStiffnessMatrix) = 0;

    ///
    /// \brief Build the sparsity pattern for stiffness matrix
    ///
    virtual void getTangentStiffnessMatrixTopology(vega::SparseMatrix** tangentStiffnessMatrix) = 0;

    ///
    /// \brief Compute both internal force \p internalForce and stiffness matrix \p tangentStiffnessMatrix at state \u
    /// \note This default implementation just call \p getInternalForce and \p getTangentStiffnessMatrix, but a more efficient implementation can be rewrite this.
    ///
    virtual void getForceAndMatrix(const Vectord& u, Vectord& internalForce, SparseMatrixd& tangentStiffnessMatrix);

    ///
    /// \brief Update the values of the Eigen sparse matrix given the linearized array of data from the Vega matrix
    ///
    static void updateValuesFromMatrix(std::shared_ptr<vega::SparseMatrix> vegaMatrix, double* values);

    ///
    /// \brief Specify tangent stiffness matrix
    ///
    virtual void setTangentStiffness(std::shared_ptr<vega::SparseMatrix> K) = 0;
};
} // namespace imstk