/////////////////////////////////////////////////////////////////////////////////
//
//  Copyright (C) Statoil ASA
//  Copyright (C) Ceetron Solutions AS
// 
//  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 "RivFaultGeometryGenerator.h"

#include <cmath>

#include "cvfDrawableGeo.h"
#include "cvfPrimitiveSetIndexedUInt.h"
#include "cvfOutlineEdgeExtractor.h"
#include "cvfStructGridGeometryGenerator.h"

#include "cvfScalarMapper.h"

#include "RigFault.h"



//--------------------------------------------------------------------------------------------------
/// 
//--------------------------------------------------------------------------------------------------
RivFaultGeometryGenerator::RivFaultGeometryGenerator(const cvf::StructGridInterface* grid, const RigFault* fault, bool computeNativeFaultFaces)
   : m_grid(grid),
   m_fault(fault),
   m_computeNativeFaultFaces(computeNativeFaultFaces)
{
    m_quadMapper = new cvf::StructGridQuadToCellFaceMapper;
    m_triangleMapper = new cvf::StuctGridTriangleToCellFaceMapper(m_quadMapper.p());
}

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

//--------------------------------------------------------------------------------------------------
/// Generate surface drawable geo from the specified region
//--------------------------------------------------------------------------------------------------
cvf::ref<cvf::DrawableGeo> RivFaultGeometryGenerator::generateSurface()
{
    computeArrays();

    CVF_ASSERT(m_vertices.notNull());

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

    cvf::ref<cvf::DrawableGeo> geo = new cvf::DrawableGeo;
    geo->setFromQuadVertexArray(m_vertices.p());

    return geo;
}

//--------------------------------------------------------------------------------------------------
/// Generates simplified mesh as line drawing
/// Must call generateSurface first 
//--------------------------------------------------------------------------------------------------
cvf::ref<cvf::DrawableGeo> RivFaultGeometryGenerator::createMeshDrawable()
{

    if (!(m_vertices.notNull() && m_vertices->size() != 0)) return nullptr;

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

    cvf::ref<cvf::UIntArray> indices = lineIndicesFromQuadVertexArray(m_vertices.p());
    cvf::ref<cvf::PrimitiveSetIndexedUInt> prim = new cvf::PrimitiveSetIndexedUInt(cvf::PT_LINES);
    prim->setIndices(indices.p());

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

//--------------------------------------------------------------------------------------------------
/// 
//--------------------------------------------------------------------------------------------------
cvf::ref<cvf::DrawableGeo> RivFaultGeometryGenerator::createOutlineMeshDrawable(double creaseAngle)
{
    if (!(m_vertices.notNull() && m_vertices->size() != 0)) return nullptr;

    cvf::OutlineEdgeExtractor ee(creaseAngle, *m_vertices);

    cvf::ref<cvf::UIntArray> indices = lineIndicesFromQuadVertexArray(m_vertices.p());
    ee.addPrimitives(4, *indices);

    cvf::ref<cvf::UIntArray> lineIndices = ee.lineIndices();
    if (lineIndices->size() == 0)
    {
        return nullptr;
    }

    cvf::ref<cvf::PrimitiveSetIndexedUInt> prim = new cvf::PrimitiveSetIndexedUInt(cvf::PT_LINES);
    prim->setIndices(lineIndices.p());

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

    return geo;
}

//--------------------------------------------------------------------------------------------------
/// 
//--------------------------------------------------------------------------------------------------
cvf::ref<cvf::UIntArray> RivFaultGeometryGenerator::lineIndicesFromQuadVertexArray(const cvf::Vec3fArray* vertexArray)
{
    CVF_ASSERT(vertexArray);

    size_t numVertices = vertexArray->size();
    int numQuads = static_cast<int>(numVertices/4);
    CVF_ASSERT(numVertices%4 == 0);

    cvf::ref<cvf::UIntArray> indices = new cvf::UIntArray;
    indices->resize(numQuads*8);

#pragma omp parallel for
    for (int i = 0; i < numQuads; i++)
    {        
        int idx = 8*i;
        indices->set(idx + 0, i*4 + 0);
        indices->set(idx + 1, i*4 + 1);
        indices->set(idx + 2, i*4 + 1);
        indices->set(idx + 3, i*4 + 2);
        indices->set(idx + 4, i*4 + 2);
        indices->set(idx + 5, i*4 + 3);
        indices->set(idx + 6, i*4 + 3);
        indices->set(idx + 7, i*4 + 0);
    }

    return indices;
}

//--------------------------------------------------------------------------------------------------
/// 
//--------------------------------------------------------------------------------------------------
void RivFaultGeometryGenerator::computeArrays()
{
    std::vector<cvf::Vec3f> vertices;
    m_quadMapper->quadToCellIndexMap().clear();
    m_quadMapper->quadToCellFaceMap().clear();

    cvf::Vec3d offset = m_grid->displayModelOffset();

    const std::vector<RigFault::FaultFace>& faultFaces = m_fault->faultFaces();

#pragma omp parallel for
    for (int fIdx = 0; fIdx < static_cast<int>(faultFaces.size()); fIdx++)
    {
        size_t cellIndex = faultFaces[fIdx].m_nativeReservoirCellIndex;
        cvf::StructGridInterface::FaceType face = faultFaces[fIdx].m_nativeFace;

        if (cellIndex >= m_cellVisibility->size()) continue;

        if (!m_computeNativeFaultFaces)
        {
            cellIndex = faultFaces[fIdx].m_oppositeReservoirCellIndex;
            face = cvf::StructGridInterface::oppositeFace(faultFaces[fIdx].m_nativeFace);
        }

        if (!(*m_cellVisibility)[cellIndex]) continue;

        cvf::Vec3d cornerVerts[8];
        m_grid->cellCornerVertices(cellIndex, cornerVerts);

        cvf::ubyte faceConn[4];
        m_grid->cellFaceVertexIndices(face, faceConn);

        // Critical section to avoid two threads accessing the arrays at the same time.
#pragma omp critical
        {
            int n;
            for (n = 0; n < 4; n++)
            {
                vertices.push_back(cvf::Vec3f(cornerVerts[faceConn[n]] - offset));
            }

            // Keep track of the source cell index per quad
            m_quadMapper->quadToCellIndexMap().push_back(cellIndex);
            m_quadMapper->quadToCellFaceMap().push_back(face);
        }
    }

    m_vertices = new cvf::Vec3fArray;
    m_vertices->assign(vertices);
}

//--------------------------------------------------------------------------------------------------
/// 
//--------------------------------------------------------------------------------------------------
void RivFaultGeometryGenerator::setCellVisibility(const cvf::UByteArray* cellVisibility)
{
    m_cellVisibility = cellVisibility;
}