//
//   Copyright 2013 Pixar
//
//   Licensed under the Apache License, Version 2.0 (the "Apache License")
//   with the following modification; you may not use this file except in
//   compliance with the Apache License and the following modification to it:
//   Section 6. Trademarks. is deleted and replaced with:
//
//   6. Trademarks. This License does not grant permission to use the trade
//      names, trademarks, service marks, or product names of the Licensor
//      and its affiliates, except as required to comply with Section 4(c) of
//      the License and to reproduce the content of the NOTICE file.
//
//   You may obtain a copy of the Apache License at
//
//       http://www.apache.org/licenses/LICENSE-2.0
//
//   Unless required by applicable law or agreed to in writing, software
//   distributed under the Apache License with the above modification is
//   distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
//   KIND, either express or implied. See the Apache License for the specific
//   language governing permissions and limitations under the Apache License.
//

#include <cassert>
#include <cstdio>


#include "../../regression/common/hbr_utils.h"
#include "../../regression/common/far_utils.h"
#include "../../regression/common/cmp_utils.h"

#include "init_shapes.h"

//
// Regression testing matching Far to Hbr (default CPU implementation)
//
// Notes:
// - precision is currently held at 1e-6
//
// - results cannot be bitwise identical as some vertex interpolations
//   are not happening in the same order.
//
// - only vertex interpolation is being tested at the moment.
//
#define PRECISION 1e-6

static bool g_debugmode = false;

//------------------------------------------------------------------------------
// Vertex class implementation
struct xyzVV {

    xyzVV() { /* _pos[0]=_pos[1]=_pos[2]=0.0f; */ }

    xyzVV( int /*i*/ ) { }

    xyzVV( float x, float y, float z ) { _pos[0]=x; _pos[1]=y; _pos[2]=z; }

    xyzVV( const xyzVV & src ) { _pos[0]=src._pos[0]; _pos[1]=src._pos[1]; _pos[2]=src._pos[2]; }

   ~xyzVV( ) { }

    void AddWithWeight(const xyzVV& src, float weight) {
        _pos[0]+=weight*src._pos[0];
        _pos[1]+=weight*src._pos[1];
        _pos[2]+=weight*src._pos[2];
    }

    void AddVaryingWithWeight(const xyzVV& , float) { }

    void Clear( void * =0 ) { _pos[0]=_pos[1]=_pos[2]=0.0f; }

    void SetPosition(float x, float y, float z) { _pos[0]=x; _pos[1]=y; _pos[2]=z; }

    void ApplyVertexEdit(const OpenSubdiv::HbrVertexEdit<xyzVV> & edit) {
        const float *src = edit.GetEdit();
        switch(edit.GetOperation()) {
          case OpenSubdiv::HbrHierarchicalEdit<xyzVV>::Set:
            _pos[0] = src[0];
            _pos[1] = src[1];
            _pos[2] = src[2];
            break;
          case OpenSubdiv::HbrHierarchicalEdit<xyzVV>::Add:
            _pos[0] += src[0];
            _pos[1] += src[1];
            _pos[2] += src[2];
            break;
          case OpenSubdiv::HbrHierarchicalEdit<xyzVV>::Subtract:
            _pos[0] -= src[0];
            _pos[1] -= src[1];
            _pos[2] -= src[2];
            break;
        }
    }

    void ApplyMovingVertexEdit(const OpenSubdiv::HbrMovingVertexEdit<xyzVV> &) { }

    const float * GetPos() const { return _pos; }

    bool operator==(xyzVV const & other) const {
        if (_pos[0]==other._pos[0] &&
            _pos[1]==other._pos[1] &&
            _pos[2]==other._pos[2]) {
            return true;
        }
        return false;
    }

private:
    float _pos[3];
};

//------------------------------------------------------------------------------
typedef OpenSubdiv::HbrMesh<xyzVV>           Hmesh;

//------------------------------------------------------------------------------
typedef OpenSubdiv::Sdc::Options                       SdcOptions;
typedef OpenSubdiv::Far::TopologyLevel                 FarTopologyLevel;
typedef OpenSubdiv::Far::TopologyRefiner               FarTopologyRefiner;
typedef OpenSubdiv::Far::TopologyRefinerFactory<Shape> FarTopologyRefinerFactory;

//------------------------------------------------------------------------------
#ifdef foo
static void
printVertexData(std::vector<xyzVV> const & hbrBuffer, std::vector<xyzVV> const & farBuffer) {

    assert(hbrBuffer.size()==farBuffer.size());
    for (int i=0; i<(int)hbrBuffer.size(); ++i) {

        float const * hbr = hbrBuffer[i].GetPos(),
                    * far = farBuffer[i].GetPos();

        printf("%3d %d (%f %f %f) (%f %f %f)\n", i, hbrBuffer[i]==farBuffer[i],
                                                    hbr[0], hbr[1], hbr[2],
                                                    far[0], far[1], far[2]);
    }
}
#endif

//------------------------------------------------------------------------------
static int
compareVertexData(std::vector<xyzVV> const& farVertexData, std::vector<xyzVV> const& hbrVertexData) {

    int count=0;
    float deltaAvg[3] = {0.0f, 0.0f, 0.0f},
          deltaCnt[3] = {0.0f, 0.0f, 0.0f};

    int nverts = (int)farVertexData.size();

    for (int i=0; i<nverts; ++i) {

        xyzVV const & hbrVert = hbrVertexData[i];
        xyzVV const & farVert = farVertexData[i];

#ifdef __INTEL_COMPILER // remark #1572: floating-point equality and inequality comparisons are unreliable
#pragma warning disable 1572
#endif
        if ( hbrVert.GetPos()[0] != farVert.GetPos()[0] )
            deltaCnt[0]++;
        if ( hbrVert.GetPos()[1] != farVert.GetPos()[1] )
            deltaCnt[1]++;
        if ( hbrVert.GetPos()[2] != farVert.GetPos()[2] )
            deltaCnt[2]++;
#ifdef __INTEL_COMPILER
#pragma warning enable 1572
#endif
        float delta[3] = { hbrVert.GetPos()[0] - farVert.GetPos()[0],
                           hbrVert.GetPos()[1] - farVert.GetPos()[1],
                           hbrVert.GetPos()[2] - farVert.GetPos()[2] };

        deltaAvg[0]+=delta[0];
        deltaAvg[1]+=delta[1];
        deltaAvg[2]+=delta[2];

        float dist = sqrtf( delta[0]*delta[0]+delta[1]*delta[1]+delta[2]*delta[2]);
        if ( dist > PRECISION ) {
            if (! g_debugmode)
                printf("// HbrVertex<T> %d fails : dist=%.10f (%.10f %.10f %.10f)"
                       " (%.10f %.10f %.10f)\n", i, dist, hbrVert.GetPos()[0],
                                                          hbrVert.GetPos()[1],
                                                          hbrVert.GetPos()[2],
                                                          farVert.GetPos()[0],
                                                          farVert.GetPos()[1],
                                                          farVert.GetPos()[2] );
           count++;
        }
    }

    if (deltaCnt[0])
        deltaAvg[0]/=deltaCnt[0];
    if (deltaCnt[1])
        deltaAvg[1]/=deltaCnt[1];
    if (deltaCnt[2])
        deltaAvg[2]/=deltaCnt[2];

    if (! g_debugmode) {
        printf("  delta ratio : (%d/%d %d/%d %d/%d)\n", (int)deltaCnt[0], nverts,
                                                        (int)deltaCnt[1], nverts,
                                                        (int)deltaCnt[2], nverts );
        printf("  average delta : (%.10f %.10f %.10f)\n", deltaAvg[0],
                                                          deltaAvg[1],
                                                          deltaAvg[2] );
        if (count==0)
            printf("  success !\n");
    }
    return count;
}

static int
compareVerticesWithHbr(Shape const & shape,
                       FarTopologyRefiner const & refiner,
                       std::vector<xyzVV> const& farVertexData) {

    std::vector<xyzVV> hbrVertexData;

    Hmesh * hmesh = interpolateHbrVertexData<xyzVV>(&shape, refiner.GetMaxLevel());

    // copy Hbr vertex data into a re-ordered buffer (for easier comparison)
    GetReorderedHbrVertexData(refiner, *hmesh, &hbrVertexData);

    // compare and report differences in vertex positions
    return compareVertexData(farVertexData, hbrVertexData);
}

static bool
isBaseMeshNonManifold(FarTopologyRefiner const & refiner) {

    // Some simpler inspection methods of the RefinerLevel would help here...
    //   - vertices and edges are internally tagged as manifold or not

    FarTopologyLevel const & level = refiner.GetLevel(0);

    int nVerts = level.GetNumVertices();
    for (int i = 0; i < nVerts; ++i) {
        int nVertFaces = level.GetVertexFaces(i).size();
        int nVertEdges = level.GetVertexEdges(i).size();
        int nEdgesMinusFaces = nVertEdges - nVertFaces;
        if ((nEdgesMinusFaces > 1) || (nEdgesMinusFaces < 0)) {
            return true;
        }
    }

    int nEdges = level.GetNumEdges();
    for (int i = 0; i < nEdges; ++i) {
        int nEdgeFaces = level.GetEdgeFaces(i).size();
        if ((nEdgeFaces < 1) || (nEdgeFaces > 2)) {
            return true;
        }
        if (level.GetEdgeVertices(i)[0] == level.GetEdgeVertices(i)[1]) {
            return true;
        }
    }
    return false;
}

static bool
shapeHasHierarchicalEditTags(Shape const & shape) {

    for (int i = 0; i < (int)shape.tags.size(); ++i) {
        Shape::tag const & tag = *shape.tags[i];

        if ((tag.name == "vertexedit") || (tag.name == "edgeedit") || (tag.name == "faceedit")) {
            return true;
        }
    }
    return false;
}

static bool
areVerticesCompatibleWithHbr(Shape const & shape, FarTopologyRefiner const & refiner,
                             std::string * incompatibleString = 0)
{
    //
    // Known incompatibilities with Hbr:
    //   - non-manifold features -- Hbr does not support them
    //   - very high-valence vertex -- accumulation of Hbr inaccuracies becomes considerable
    //   - Chaikin creasing -- Hbr known to be incorrect
    //   - hierarchical edits -- not supported by FarTopologyRefiner
    //       - Shape will include tags "vertexedit", "edgeedit" and "faceedit"
    //
    if (isBaseMeshNonManifold(refiner)) {
        if (incompatibleString) {
            *incompatibleString = std::string("mesh is non-manifold");
        }
        return false;
    }
    if (refiner.GetMaxValence() > 64) {
        if (incompatibleString) {
            *incompatibleString = std::string("vertices of excessively high valence present");
        }
        return false;
    }
    if (refiner.GetSchemeOptions().GetCreasingMethod() == SdcOptions::CREASE_CHAIKIN) {
        if (incompatibleString) {
            *incompatibleString = std::string("assigned crease method is Chaikin");
        }
        return false;
    }
    if (shape.isLeftHanded) {
        if (incompatibleString) {
            *incompatibleString = std::string("mesh is left-handed");
        }
        return false;
    }
    if (shapeHasHierarchicalEditTags(shape)) {
        if (incompatibleString) {
            *incompatibleString = std::string("hierarchical edits no longer supported");
        }
        return false;
    }
    return true;
}

//------------------------------------------------------------------------------
static int
checkMesh(Shape const & shape, std::string const& name, int maxlevel) {

    std::string warningDetail;

    static char const * schemes[] = { "Bilinear", "Catmark", "Loop" };
    printf("- %-25s ( %-8s ): \n", name.c_str(), schemes[shape.scheme]);

    // Refine and interpolate vertex data for every shape:
    std::vector<xyzVV> farVertexData;

    FarTopologyRefiner * refiner = InterpolateFarVertexData<xyzVV>(shape, maxlevel, farVertexData);

    // Perform relevant tests and accumulate failures:
    int failureCount = 0;

    if (areVerticesCompatibleWithHbr(shape, *refiner, &warningDetail)) {
        failureCount = compareVerticesWithHbr(shape, *refiner, farVertexData);
    } else {
        printf("  warning : vertex data not compared with Hbr (%s)\n", warningDetail.c_str());
    }

    return failureCount;
}

//------------------------------------------------------------------------------
int main(int /* argc */, char ** /* argv */) {

    int levels=5, total=0;

    initShapes();

    if (g_debugmode)
        printf("[ ");
    else
        printf("precision : %f\n",PRECISION);

    for (int i=0; i<(int)g_shapes.size(); ++i) {
        ShapeDesc const & desc = g_shapes[i];

        Shape * shape = Shape::parseObj(desc);
        if (shape) {
            // May want to inspect and/or modify the shape before proceeding...

            total+=checkMesh(*shape, desc.name, levels);
        }
        delete shape;
    }

    if (g_debugmode)
        printf("]\n");
    else {
        if (total==0)
          printf("All tests passed.\n");
        else
          printf("Total failures : %d\n", total);
    }
}

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