/////////////////////////////////////////////////////////////////////////////////
//
//  Copyright (C) Statoil ASA
//
//  ResInsight is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  ResInsight is distributed in the hope that it will be useful, but WITHOUT ANY
//  WARRANTY; without even the implied warranty of MERCHANTABILITY or
//  FITNESS FOR A PARTICULAR PURPOSE.
//
//  See the GNU General Public License at <http://www.gnu.org/licenses/gpl.html>
//  for more details.
//
/////////////////////////////////////////////////////////////////////////////////

#include "RivBoxIntersectionGeometryGenerator.h"

#include "RivIntersectionHexGridInterface.h"

#include "RimBoxIntersection.h"
#include "RimCase.h"
#include "RimGridView.h"

#include "cafHexGridIntersectionTools/cafHexGridIntersectionTools.h"

#include "cvfDrawableGeo.h"
#include "cvfPlane.h"
#include "cvfPrimitiveSetDirect.h"
#include "cvfStructGrid.h"

#include <array>

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
RivBoxIntersectionGeometryGenerator::RivBoxIntersectionGeometryGenerator( RimBoxIntersection*                    intersectionBox,
                                                                          const RivIntersectionHexGridInterface* grid )
    : m_intersectionBoxDefinition( intersectionBox )
    , m_hexGrid( grid )
{
    m_triangleVxes       = new cvf::Vec3fArray;
    m_cellBorderLineVxes = new cvf::Vec3fArray;
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
RivBoxIntersectionGeometryGenerator::~RivBoxIntersectionGeometryGenerator()
{
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
bool RivBoxIntersectionGeometryGenerator::isAnyGeometryPresent() const
{
    return m_triangleVxes->size() != 0;
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
cvf::ref<cvf::DrawableGeo> RivBoxIntersectionGeometryGenerator::generateSurface( cvf::UByteArray* visibleCells )
{
    calculateArrays( visibleCells );

    CVF_ASSERT( m_triangleVxes.notNull() );

    if ( m_triangleVxes->size() == 0 ) return nullptr;

    cvf::ref<cvf::DrawableGeo> geo = new cvf::DrawableGeo;
    geo->setFromTriangleVertexArray( m_triangleVxes.p() );

    return geo;
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
cvf::ref<cvf::DrawableGeo> RivBoxIntersectionGeometryGenerator::createMeshDrawable()
{
    if ( !m_cellBorderLineVxes.notNull() || m_cellBorderLineVxes->size() == 0 ) return nullptr;

    cvf::ref<cvf::DrawableGeo> geo = new cvf::DrawableGeo;
    geo->setVertexArray( m_cellBorderLineVxes.p() );

    cvf::ref<cvf::PrimitiveSetDirect> prim = new cvf::PrimitiveSetDirect( cvf::PT_LINES );
    prim->setIndexCount( m_cellBorderLineVxes->size() );

    geo->addPrimitiveSet( prim.p() );
    return geo;
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
const std::vector<size_t>& RivBoxIntersectionGeometryGenerator::triangleToCellIndex() const
{
    CVF_ASSERT( m_triangleVxes->size() );
    return m_triangleToCellIdxMap;
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
const std::vector<RivIntersectionVertexWeights>& RivBoxIntersectionGeometryGenerator::triangleVxToCellCornerInterpolationWeights() const
{
    CVF_ASSERT( m_triangleVxes->size() );
    return m_triVxToCellCornerWeights;
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
const cvf::Vec3fArray* RivBoxIntersectionGeometryGenerator::triangleVxes() const
{
    CVF_ASSERT( m_triangleVxes->size() );

    return m_triangleVxes.p();
}

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

class Box
{
public:
    using FaceType = cvf::StructGridInterface::FaceType;

    Box( const cvf::Mat4d& origin, const cvf::Vec3d& size )
        : m_origin( origin )
        , m_size( size )
    {
    }

    std::array<cvf::Plane, 6> planes()
    {
        std::array<cvf::Plane, 6> boxPlanes;

        boxPlanes[FaceType::POS_I].setFromPointAndNormal( m_origin.translation() + m_size, cvf::Vec3d( m_origin.col( 0 ) ) );
        boxPlanes[FaceType::NEG_I].setFromPointAndNormal( m_origin.translation(), -cvf::Vec3d( m_origin.col( 0 ) ) );
        boxPlanes[FaceType::POS_J].setFromPointAndNormal( m_origin.translation() + m_size, cvf::Vec3d( m_origin.col( 1 ) ) );
        boxPlanes[FaceType::NEG_J].setFromPointAndNormal( m_origin.translation(), -cvf::Vec3d( m_origin.col( 1 ) ) );
        boxPlanes[FaceType::POS_K].setFromPointAndNormal( m_origin.translation() + m_size, cvf::Vec3d( m_origin.col( 2 ) ) );
        boxPlanes[FaceType::NEG_K].setFromPointAndNormal( m_origin.translation(), -cvf::Vec3d( m_origin.col( 2 ) ) );

        return boxPlanes;
    }

    std::array<cvf::Vec3d, 4> faceCorners( FaceType face )
    {
        std::array<cvf::Vec3d, 4> corners;

        cvf::Vec3d sx = cvf::Vec3d( m_origin.col( 0 ) ) * m_size[0];
        cvf::Vec3d sy = cvf::Vec3d( m_origin.col( 1 ) ) * m_size[1];
        cvf::Vec3d sz = cvf::Vec3d( m_origin.col( 2 ) ) * m_size[2];

        switch ( face )
        {
            case FaceType::POS_I:
                corners[0] = m_origin.translation() + sx;
                corners[1] = m_origin.translation() + sx + sy;
                corners[2] = m_origin.translation() + sx + sy + sz;
                corners[3] = m_origin.translation() + sx + sz;
                break;
            case FaceType::NEG_I:
                corners[0] = m_origin.translation();
                corners[1] = m_origin.translation() + sz;
                corners[2] = m_origin.translation() + sy + sz;
                corners[3] = m_origin.translation() + sy;
                break;
            case FaceType::POS_J:
                corners[0] = m_origin.translation() + sy;
                corners[1] = m_origin.translation() + sy + sz;
                corners[2] = m_origin.translation() + sy + sx + sz;
                corners[3] = m_origin.translation() + sy + sx;
                break;
            case FaceType::NEG_J:
                corners[0] = m_origin.translation();
                corners[1] = m_origin.translation() + sx;
                corners[2] = m_origin.translation() + sx + sz;
                corners[3] = m_origin.translation() + sz;
                break;
            case FaceType::POS_K:
                corners[0] = m_origin.translation() + sz;
                corners[1] = m_origin.translation() + sz + sx;
                corners[2] = m_origin.translation() + sz + sx + sy;
                corners[3] = m_origin.translation() + sz + sy;
                break;
            case FaceType::NEG_K:
                corners[0] = m_origin.translation();
                corners[1] = m_origin.translation() + sy;
                corners[2] = m_origin.translation() + sx + sy;
                corners[3] = m_origin.translation() + sx;
                break;
        }

        return corners;
    }

    // Returns the four adjacent faces in the Pos, Neg, Pos, Neg order

    std::array<FaceType, 4> adjacentFaces( FaceType face )
    {
        std::array<FaceType, 4> clipFaces     = { FaceType::NO_FACE, FaceType::NO_FACE, FaceType::NO_FACE, FaceType::NO_FACE };
        FaceType                oppFace       = cvf::StructGridInterface::oppositeFace( face );
        int                     clipFaceCount = 0;
        for ( int faceCand = 0; faceCand < 6; ++faceCand )
        {
            if ( faceCand != face && faceCand != oppFace )
            {
                clipFaces[clipFaceCount] = (FaceType)faceCand;
                clipFaceCount++;
            }
        }

        return clipFaces;
    }

private:
    cvf::Mat4d m_origin;
    cvf::Vec3d m_size;
};

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
RimBoxIntersection* RivBoxIntersectionGeometryGenerator::intersectionBox() const
{
    return m_intersectionBoxDefinition;
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
void RivBoxIntersectionGeometryGenerator::calculateArrays( cvf::UByteArray* visibleCells )
{
    if ( m_triangleVxes->size() ) return;

    std::vector<cvf::Vec3f> triangleVertices;
    std::vector<cvf::Vec3f> cellBorderLineVxes;

    cvf::Vec3d displayOffset( 0, 0, 0 );
    {
        auto gridView = m_intersectionBoxDefinition->firstAncestorOrThisOfType<RimGridView>();
        if ( gridView && gridView->ownerCase() )
        {
            displayOffset = gridView->ownerCase()->displayModelOffset();
        }
    }

    Box                       box( m_intersectionBoxDefinition->boxOrigin(), m_intersectionBoxDefinition->boxSize() );
    std::array<cvf::Plane, 6> boxPlanes = box.planes();

    RimBoxIntersection::SinglePlaneState singlePlane = m_intersectionBoxDefinition->singlePlaneState();

    int startFace = 0;
    int endFace   = 5;
    if ( singlePlane == RimBoxIntersection::PLANE_STATE_X ) startFace = endFace = Box::FaceType::POS_I;
    if ( singlePlane == RimBoxIntersection::PLANE_STATE_Y ) startFace = endFace = Box::FaceType::POS_J;
    if ( singlePlane == RimBoxIntersection::PLANE_STATE_Z ) startFace = endFace = Box::FaceType::POS_K;

    for ( int faceIdx = startFace; faceIdx <= endFace; ++faceIdx )
    {
        cvf::Plane plane = boxPlanes[faceIdx];

        std::array<Box::FaceType, 4> clipFaces = box.adjacentFaces( (Box::FaceType)faceIdx );

        cvf::Plane p1Plane = boxPlanes[clipFaces[1]];
        cvf::Plane p2Plane = boxPlanes[clipFaces[0]];
        cvf::Plane p3Plane = boxPlanes[clipFaces[3]];
        cvf::Plane p4Plane = boxPlanes[clipFaces[2]];

        p1Plane.flip();
        p2Plane.flip();
        p3Plane.flip();
        p4Plane.flip();

        std::array<cvf::Vec3d, 4> faceCorners = box.faceCorners( (Box::FaceType)faceIdx );

        cvf::BoundingBox sectionBBox;

        for ( cvf::Vec3d& corner : faceCorners )
            sectionBBox.add( corner );

        // Similar code as IntersectionGenerator :

        std::vector<size_t> columnCellCandidates = m_hexGrid->findIntersectingCells( sectionBBox );

        std::vector<caf::HexGridIntersectionTools::ClipVx> hexPlaneCutTriangleVxes;
        hexPlaneCutTriangleVxes.reserve( 5 * 3 );
        std::vector<int> cellFaceForEachTriangleEdge;
        cellFaceForEachTriangleEdge.reserve( 5 * 3 );
        cvf::Vec3d cellCorners[8];
        size_t     cornerIndices[8];

        for ( size_t cccIdx = 0; cccIdx < columnCellCandidates.size(); ++cccIdx )
        {
            size_t globalCellIdx = columnCellCandidates[cccIdx];

            if ( ( visibleCells != nullptr ) && ( ( *visibleCells )[globalCellIdx] == 0 ) ) continue;
            if ( !m_hexGrid->useCell( globalCellIdx ) ) continue;

            hexPlaneCutTriangleVxes.clear();
            m_hexGrid->cellCornerVertices( globalCellIdx, cellCorners );
            m_hexGrid->cellCornerIndices( globalCellIdx, cornerIndices );

            caf::HexGridIntersectionTools::planeHexIntersectionMC( plane,
                                                                   cellCorners,
                                                                   cornerIndices,
                                                                   &hexPlaneCutTriangleVxes,
                                                                   &cellFaceForEachTriangleEdge );

            std::vector<caf::HexGridIntersectionTools::ClipVx> clippedTriangleVxes_once;
            std::vector<int>                                   cellFaceForEachClippedTriangleEdge_once;
            caf::HexGridIntersectionTools::clipTrianglesBetweenTwoParallelPlanes( hexPlaneCutTriangleVxes,
                                                                                  cellFaceForEachTriangleEdge,
                                                                                  p1Plane,
                                                                                  p2Plane,
                                                                                  &clippedTriangleVxes_once,
                                                                                  &cellFaceForEachClippedTriangleEdge_once );

            for ( caf::HexGridIntersectionTools::ClipVx& clvx : clippedTriangleVxes_once )
                if ( !clvx.isVxIdsNative ) clvx.derivedVxLevel = 0;

            std::vector<caf::HexGridIntersectionTools::ClipVx> clippedTriangleVxes;
            std::vector<int>                                   cellFaceForEachClippedTriangleEdge;

            caf::HexGridIntersectionTools::clipTrianglesBetweenTwoParallelPlanes( clippedTriangleVxes_once,
                                                                                  cellFaceForEachClippedTriangleEdge_once,
                                                                                  p3Plane,
                                                                                  p4Plane,
                                                                                  &clippedTriangleVxes,
                                                                                  &cellFaceForEachClippedTriangleEdge );
            for ( caf::HexGridIntersectionTools::ClipVx& clvx : clippedTriangleVxes )
                if ( !clvx.isVxIdsNative && clvx.derivedVxLevel == -1 ) clvx.derivedVxLevel = 1;

            size_t clippedTriangleCount = clippedTriangleVxes.size() / 3;

            for ( uint tIdx = 0; tIdx < clippedTriangleCount; ++tIdx )
            {
                uint triVxIdx = tIdx * 3;

                // Accumulate triangle vertices

                cvf::Vec3f p0( clippedTriangleVxes[triVxIdx + 0].vx - displayOffset );
                cvf::Vec3f p1( clippedTriangleVxes[triVxIdx + 1].vx - displayOffset );
                cvf::Vec3f p2( clippedTriangleVxes[triVxIdx + 2].vx - displayOffset );

                triangleVertices.push_back( p0 );
                triangleVertices.push_back( p1 );
                triangleVertices.push_back( p2 );

                // Accumulate mesh lines

#define isFace( faceEnum ) ( 0 <= faceEnum && faceEnum <= 5 )

                if ( isFace( cellFaceForEachClippedTriangleEdge[triVxIdx] ) )
                {
                    cellBorderLineVxes.push_back( p0 );
                    cellBorderLineVxes.push_back( p1 );
                }
                if ( isFace( cellFaceForEachClippedTriangleEdge[triVxIdx + 1] ) )
                {
                    cellBorderLineVxes.push_back( p1 );
                    cellBorderLineVxes.push_back( p2 );
                }
                if ( isFace( cellFaceForEachClippedTriangleEdge[triVxIdx + 2] ) )
                {
                    cellBorderLineVxes.push_back( p2 );
                    cellBorderLineVxes.push_back( p0 );
                }

                // Mapping to cell index

                m_triangleToCellIdxMap.push_back( globalCellIdx );

                // Interpolation from nodes
                for ( int i = 0; i < 3; ++i )
                {
                    caf::HexGridIntersectionTools::ClipVx cvx = clippedTriangleVxes[triVxIdx + i];
                    if ( cvx.isVxIdsNative )
                    {
                        m_triVxToCellCornerWeights.push_back(
                            RivIntersectionVertexWeights( cvx.clippedEdgeVx1Id, cvx.clippedEdgeVx2Id, cvx.normDistFromEdgeVx1 ) );
                    }
                    else
                    {
                        caf::HexGridIntersectionTools::ClipVx cvx1;
                        caf::HexGridIntersectionTools::ClipVx cvx2;

                        if ( cvx.derivedVxLevel == 0 )
                        {
                            cvx1 = hexPlaneCutTriangleVxes[cvx.clippedEdgeVx1Id];
                            cvx2 = hexPlaneCutTriangleVxes[cvx.clippedEdgeVx2Id];
                        }
                        else if ( cvx.derivedVxLevel == 1 )
                        {
                            cvx1 = clippedTriangleVxes_once[cvx.clippedEdgeVx1Id];
                            cvx2 = clippedTriangleVxes_once[cvx.clippedEdgeVx2Id];
                        }
                        else
                        {
                            CVF_ASSERT( false );
                        }

                        if ( cvx1.isVxIdsNative && cvx2.isVxIdsNative )
                        {
                            m_triVxToCellCornerWeights.push_back( RivIntersectionVertexWeights( cvx1.clippedEdgeVx1Id,
                                                                                                cvx1.clippedEdgeVx2Id,
                                                                                                cvx1.normDistFromEdgeVx1,
                                                                                                cvx2.clippedEdgeVx1Id,
                                                                                                cvx2.clippedEdgeVx2Id,
                                                                                                cvx2.normDistFromEdgeVx1,
                                                                                                cvx.normDistFromEdgeVx1 ) );
                        }
                        else
                        {
                            caf::HexGridIntersectionTools::ClipVx cvx11;
                            caf::HexGridIntersectionTools::ClipVx cvx12;
                            caf::HexGridIntersectionTools::ClipVx cvx21;
                            caf::HexGridIntersectionTools::ClipVx cvx22;

                            if ( cvx1.isVxIdsNative )
                            {
                                cvx11 = cvx1;
                                cvx12 = cvx1;
                            }
                            else if ( cvx1.derivedVxLevel == 0 )
                            {
                                cvx11 = hexPlaneCutTriangleVxes[cvx1.clippedEdgeVx1Id];
                                cvx12 = hexPlaneCutTriangleVxes[cvx1.clippedEdgeVx2Id];
                            }
                            else if ( cvx2.derivedVxLevel == 1 )
                            {
                                cvx11 = clippedTriangleVxes_once[cvx1.clippedEdgeVx1Id];
                                cvx12 = clippedTriangleVxes_once[cvx1.clippedEdgeVx2Id];
                            }
                            else
                            {
                                CVF_ASSERT( false );
                            }

                            if ( cvx2.isVxIdsNative )
                            {
                                cvx21 = cvx2;
                                cvx22 = cvx2;
                            }
                            else if ( cvx2.derivedVxLevel == 0 )
                            {
                                cvx21 = hexPlaneCutTriangleVxes[cvx2.clippedEdgeVx1Id];
                                cvx22 = hexPlaneCutTriangleVxes[cvx2.clippedEdgeVx2Id];
                            }
                            else if ( cvx2.derivedVxLevel == 1 )
                            {
                                cvx21 = clippedTriangleVxes_once[cvx2.clippedEdgeVx1Id];
                                cvx22 = clippedTriangleVxes_once[cvx2.clippedEdgeVx2Id];
                            }
                            else
                            {
                                CVF_ASSERT( false );
                            }

                            CVF_TIGHT_ASSERT( cvx11.isVxIdsNative && cvx12.isVxIdsNative && cvx21.isVxIdsNative && cvx22.isVxIdsNative );

                            m_triVxToCellCornerWeights.push_back( RivIntersectionVertexWeights( cvx11.clippedEdgeVx1Id,
                                                                                                cvx11.clippedEdgeVx2Id,
                                                                                                cvx11.normDistFromEdgeVx1,
                                                                                                cvx12.clippedEdgeVx1Id,
                                                                                                cvx12.clippedEdgeVx2Id,
                                                                                                cvx2.normDistFromEdgeVx1,
                                                                                                cvx21.clippedEdgeVx1Id,
                                                                                                cvx21.clippedEdgeVx2Id,
                                                                                                cvx21.normDistFromEdgeVx1,
                                                                                                cvx22.clippedEdgeVx1Id,
                                                                                                cvx22.clippedEdgeVx2Id,
                                                                                                cvx22.normDistFromEdgeVx1,
                                                                                                cvx1.normDistFromEdgeVx1,
                                                                                                cvx2.normDistFromEdgeVx1,
                                                                                                cvx.normDistFromEdgeVx1 ) );
                        }
                    }
                }
            }
        }
    }
    m_cellBorderLineVxes->assign( cellBorderLineVxes );
    m_triangleVxes->assign( triangleVertices );
}