///////////////////////////////////////////////////////////////////////////////
//
// File: MatrixFreeBase.h
//
// For more information, please see: http://www.nektar.info
//
// The MIT License
//
// Copyright (c) 2006 Division of Applied Mathematics, Brown University (USA),
// Department of Aeronautics, Imperial College London (UK), and Scientific
// Computing and Imaging Institute, University of Utah (USA).
//
// 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.
//
// Description: base class definition for matrrix free type
//
///////////////////////////////////////////////////////////////////////////////

#ifndef NEKTAR_LIBRARY_COLLECTIONS_MATRIXFREEBASE_H
#define NEKTAR_LIBRARY_COLLECTIONS_MATRIXFREEBASE_H

#include <StdRegions/StdExpansion.h>

namespace Nektar::Collections
{

class MatrixFreeBase
{
public:
    // Default constructor
    MatrixFreeBase() = default;

    MatrixFreeBase(const unsigned int nIn, const unsigned int nOut,
                   const unsigned int nCollSize)
        : m_nIn(nIn * nCollSize), m_nOut(nOut * nCollSize)
    {
    }

protected:
    /// flag for padding
    bool m_isPadded{false};
    ///  size after padding
    unsigned int m_nElmtPad;
    unsigned int m_nIn;
    unsigned int m_nOut;
};

class MatrixFreeOneInOneOut : protected MatrixFreeBase
{
public:
    /// Constructor
    MatrixFreeOneInOneOut(const unsigned int nIn, const unsigned int nOut,
                          const unsigned int nCollSize)
        : MatrixFreeBase(nIn, nOut, nCollSize)
    {
        // Padding if needed
        using vec_t           = tinysimd::simd<NekDouble>;
        const auto nElmtNoPad = nCollSize;
        m_nElmtPad            = nElmtNoPad;

        if (nElmtNoPad % vec_t::width != 0)
        {
            m_isPadded = true;
            m_nElmtPad =
                nElmtNoPad + vec_t::width - (nElmtNoPad % vec_t::width);
            m_input  = Array<OneD, NekDouble>{nIn * m_nElmtPad, 0.0};
            m_output = Array<OneD, NekDouble>{nOut * m_nElmtPad, 0.0};
        }
    }

protected:
    /// padded input/output vectors
    Array<OneD, NekDouble> m_input, m_output;
};

class MatrixFreeMultiInOneOut : protected MatrixFreeBase
{
public:
    /// Constructor
    MatrixFreeMultiInOneOut(const unsigned int coordim, const unsigned int nIn,
                            const unsigned int nOut,
                            const unsigned int nCollSize)
        : MatrixFreeBase(nIn, nOut, nCollSize)
    {
        m_coordim = coordim;

        // Padding if needed
        using vec_t           = tinysimd::simd<NekDouble>;
        const auto nElmtNoPad = nCollSize;
        m_nElmtPad            = nElmtNoPad;

        if (nElmtNoPad % vec_t::width != 0)
        {
            m_isPadded = true;
            m_nElmtPad =
                nElmtNoPad + vec_t::width - (nElmtNoPad % vec_t::width);

            m_input    = Array<OneD, Array<OneD, NekDouble>>(m_coordim);
            m_input[0] = Array<OneD, NekDouble>{nIn * m_nElmtPad, 0.0};
            if (m_coordim == 2)
            {
                m_input[1] = Array<OneD, NekDouble>{nIn * m_nElmtPad, 0.0};
            }
            else if (m_coordim == 3)
            {
                m_input[1] = Array<OneD, NekDouble>{nIn * m_nElmtPad, 0.0};
                m_input[2] = Array<OneD, NekDouble>{nIn * m_nElmtPad, 0.0};
            }
            m_output = Array<OneD, NekDouble>{nOut * m_nElmtPad, 0.0};
        }
    }

protected:
    /// coordinates dimension
    unsigned short m_coordim;
    /// padded input/output vectors
    Array<OneD, Array<OneD, NekDouble>> m_input;
    Array<OneD, NekDouble> m_output;
};

class MatrixFreeOneInMultiOut : protected MatrixFreeBase
{
public:
    /// Constructor
    MatrixFreeOneInMultiOut(const unsigned int coordim, const unsigned int nIn,
                            const unsigned int nOut,
                            const unsigned int nCollSize)
        : MatrixFreeBase(nIn, nOut, nCollSize)
    {
        m_coordim = coordim;

        // Padding if needed
        using vec_t           = tinysimd::simd<NekDouble>;
        const auto nElmtNoPad = nCollSize;
        m_nElmtPad            = nElmtNoPad;

        if (nElmtNoPad % vec_t::width != 0)
        {
            m_isPadded = true;
            m_nElmtPad =
                nElmtNoPad + vec_t::width - (nElmtNoPad % vec_t::width);

            m_input = Array<OneD, NekDouble>{nIn * m_nElmtPad, 0.0};

            m_output    = Array<OneD, Array<OneD, NekDouble>>(m_coordim);
            m_output[0] = Array<OneD, NekDouble>{nOut * m_nElmtPad, 0.0};
            if (m_coordim == 2)
            {
                m_output[1] = Array<OneD, NekDouble>{nOut * m_nElmtPad, 0.0};
            }
            else if (m_coordim == 3)
            {
                m_output[1] = Array<OneD, NekDouble>{nOut * m_nElmtPad, 0.0};
                m_output[2] = Array<OneD, NekDouble>{nOut * m_nElmtPad, 0.0};
            }
        }
    }

protected:
    /// coordinates dimension
    unsigned short m_coordim;
    /// padded input/output vectors
    Array<OneD, NekDouble> m_input;
    Array<OneD, Array<OneD, NekDouble>> m_output;
};
} // namespace Nektar::Collections
#endif // NEKTAR_LIBRARY_COLLECTIONS_MATRIXFREEBASE_H
