//
//   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.
//

#ifndef FAR_PATCH_TABLES_FACTORY_H
#define FAR_PATCH_TABLES_FACTORY_H

#include "../version.h"

#include "../far/patchTables.h"

namespace OpenSubdiv {
namespace OPENSUBDIV_VERSION {

//  Forward declarations (for internal implementation purposes):
namespace Vtr { class Level; }

namespace Far {

class TopologyRefiner;

class PatchTablesFactoryBase {
public:
    //  PatchFaceTag
    //  A simple struct containing all information gathered about a face that is relevant
    //  to constructing a patch for it (some of these enums should probably be defined more
    //  as part of PatchTables)
    //
    //  Like the HbrFace<T>::AdaptiveFlags, this struct aggregates all of the face tags
    //  supporting feature adaptive refinement.  For now it is not used elsewhere and can
    //  remain local to this implementation, but we may want to move it into a header of
    //  its own if it has greater use later.
    //
    //  Note that several properties being assigned here attempt to do so given a 4-bit
    //  mask of properties at the edges or vertices of the quad.  Still not sure exactly
    //  what will be done this way, but the goal is to create lookup tables (of size 16
    //  for the 4 bits) to quickly determine was is needed, rather than iteration and
    //  branching on the edges or vertices.
    //
    struct PatchFaceTag {
    public:
        unsigned int   _hasPatch        : 1;
        unsigned int   _isRegular       : 1;
        unsigned int   _transitionMask  : 4;
        unsigned int   _boundaryMask    : 4;
        unsigned int   _boundaryIndex   : 2;
        unsigned int   _boundaryCount   : 3;
        unsigned int   _hasBoundaryEdge : 3;
        unsigned int   _isSingleCrease  : 1;

        void clear();
        void assignBoundaryPropertiesFromEdgeMask(int boundaryEdgeMask);
        void assignBoundaryPropertiesFromVertexMask(int boundaryVertexMask);
        void assignTransitionPropertiesFromEdgeMask(int transitionMask) {
            _transitionMask = transitionMask;
        }
    };
    typedef std::vector<PatchFaceTag> PatchTagVector;

    struct Options {

        Options(unsigned int maxIsolation=10) :
             generateAllLevels(false),
             triangulateQuads(false),
             useSingleCreasePatch(false),
             maxIsolationLevel(maxIsolation),
             generateFVarTables(false),
             useFVarQuadEndCaps(true), // XXXX change to false when FVar Gregory is ready
             numFVarChannels(-1),
             fvarChannelIndices(0)
        { }

        unsigned int generateAllLevels    : 1, ///< Include levels from 'firstLevel' to 'maxLevel' (Uniform mode only)
                     triangulateQuads     : 1, ///< Triangulate 'QUADS' primitives (Uniform mode only)
                     useSingleCreasePatch : 1, ///< Use single crease patch
                     maxIsolationLevel    : 4, ///< Cap adaptive feature isolation to the given level (max. 10)

                     // face-varying
                     generateFVarTables   : 1, ///< Generate face-varying patch tables
                     useFVarQuadEndCaps   : 1; ///< Use bilinear quads as end-caps around extraordinary vertices

        int          numFVarChannels;          ///< Number of channel indices and interpolation modes passed
        int const *  fvarChannelIndices;       ///< List containing the indices of the channels selected for the factory
    };

    /// \brief Factory constructor for PatchTables
    ///
    /// @param refiner              TopologyRefiner from which to generate patches
    ///
    /// @param options              Options controlling the creation of the tables
    ///
    /// @return                     A new instance of PatchTables
    ///
    static PatchTables * Create(TopologyRefiner const & refiner,
                                PatchTablesFactoryBase::Options options=Options());
protected:
    //
    // Private helper structures
    //
    struct AdaptiveContext;

    //
    //  Methods for allocating and managing the patch table data arrays:
    //
    static PatchTables * createUniform(TopologyRefiner const & refiner, Options options);

    static void allocateVertexTables(PatchTables * tables, int nlevels, bool hasSharpness);

    static void allocateFVarChannels(TopologyRefiner const & refiner,
         Options options, int npatches, PatchTables * tables);

    static PatchParam * computePatchParam(TopologyRefiner const & refiner,
        int level, int face, int rotation,
        int boundaryMask, int transitionMask, PatchParam * coord);

    static int gatherFVarData(AdaptiveContext & state,
        int level, Index faceIndex, Index levelFaceOffset, int rotation,
                              Index const * levelOffsets, Index fofss, Index ** fptrs);

};

/// \brief a templated patchtable factory parameterized by end cap strategy class..
///
///
template <typename ENDCAP_FACTORY>
class PatchTablesFactoryT : public PatchTablesFactoryBase {

public:

    /// \brief Factory constructor for PatchTables
    ///
    /// @param refiner              TopologyRefiner from which to generate patches
    ///
    /// @param options              Options controlling the creation of the tables
    ///
    /// @param endCapFactory        If provided, it accumulates end patches
    ///                             for later patch/stencil generation
    ///
    /// @return                     A new instance of PatchTables
    ///
    static PatchTables * Create(TopologyRefiner const & refiner,
                                PatchTablesFactoryBase::Options options=Options(),
                                ENDCAP_FACTORY *endCapFactory=NULL);

private:
    static PatchTables * createAdaptive(TopologyRefiner const & refiner, Options options,
                                        ENDCAP_FACTORY *);

    //
    //  High-level methods for identifying and populating patches associated with faces:
    //

    static void identifyAdaptivePatches(AdaptiveContext & state, ENDCAP_FACTORY *);

    static void populateAdaptivePatches(AdaptiveContext & state, ENDCAP_FACTORY *);

private:
};

/// \brief Default endcap factory (does nothing for end cap)
///
///
class EndCapNoneFactory {
public:
    PatchDescriptor::Type GetPatchType(PatchTablesFactoryBase::PatchFaceTag const &) const {
        return PatchDescriptor::NON_PATCH;
    }
    ConstIndexArray GetTopology(Vtr::Level const &/*level*/, Index /*faceIndex*/,
                                PatchTablesFactoryBase::PatchFaceTag const * /*levelPatchTags*/,
                                int /*levelVertOffset*/) {
        return ConstIndexArray();
    }
};

typedef PatchTablesFactoryT<EndCapNoneFactory> PatchTablesFactory;

} // end namespace Far

} // end namespace OPENSUBDIV_VERSION
using namespace OPENSUBDIV_VERSION;

} // end namespace OpenSubdiv


#endif /* FAR_PATCH_TABLES_FACTORY_H */