// Copyright Epic Games, Inc. All Rights Reserved.

#pragma once

#include "dna/Defs.h"
#include "dna/layers/DescriptorReader.h"
#include "dna/types/Aliases.h"
#include "dna/types/Vector3.h"

#include <cstdint>

namespace dna {

/**
    @brief Mapping that associates a blend shape channel to it's mesh.
*/
struct MeshBlendShapeChannelMapping {
    std::uint16_t meshIndex;
    std::uint16_t blendShapeChannelIndex;
};

/**
    @brief Read-only accessors for DNA attributes that represent the rig's static data.
    @warning
        Implementors should inherit from Reader itself and not this class.
    @see Reader
*/
class DNAAPI DefinitionReader : public DescriptorReader {
    protected:
        virtual ~DefinitionReader();

    public:
        virtual std::uint16_t getGUIControlCount() const = 0;
        /**
            @brief Name of the requested GUI control.
            @param index
                A name's position in the zero-indexed array of GUI control names.
            @warning
                The index must be less than the value returned by getGUIControlCount.
            @return View over the GUI control name string.
        */
        virtual StringView getGUIControlName(std::uint16_t index) const = 0;

        virtual std::uint16_t getRawControlCount() const = 0;
        /**
            @brief Name of the requested raw control.
            @param index
                A name's position in the zero-indexed array of raw control names.
            @warning
                The index must be less than the value returned by getRawControlCount.
            @return View over the control name string.
        */
        virtual StringView getRawControlName(std::uint16_t index) const = 0;

        virtual std::uint16_t getJointCount() const = 0;
        /**
            @brief Name of the requested joint.
            @param index
                A name's position in the zero-indexed array of joint names.
            @warning
                The index must be less than the value returned by getJointCount.
            @return View over the joint name string.
        */
        virtual StringView getJointName(std::uint16_t index) const = 0;
        /**
            @brief Number of joint index lists.
            @note
                This value is useful only in the context of DefinitionWriter.
        */
        virtual std::uint16_t getJointIndexListCount() const = 0;
        /**
            @brief List of joint indices for the specified LOD.
            @param lod
                The level of detail which joints are being requested.
            @warning
                The lod index must be less than the value returned by getLODCount.
            @return View over the joint indices.
            @see getLODCount
            @see getJointName
        */
        virtual ConstArrayView<std::uint16_t> getJointIndicesForLOD(std::uint16_t lod) const = 0;
        /**
            @brief Index of the requested joint's parent.
            @note
                The joint hierarchy may be traversed and reconstructed using this function. Example:
                Joint names: [A, B, C, D, E, F, G, H, I]
                Hierarchy:   [0, 0, 0, 1, 1, 4, 2, 6, 2]
                Describes the following hierarchy:
                A
                + B
                | + D
                | + E
                |   + F
                + C
                  + G
                  | + H
                  + I

                Requesting the parent index of joint 5 (joint name: F) would return 4 (joint name: E).
                Requesting the parent index of the root joint: 0 (joint name: A) would return the same index 0.
                An out of bounds request (an index greater than the number of joints returns UINT16_MAX).
            @param index
                The joint index which parent is being requested.
        */
        virtual std::uint16_t getJointParentIndex(std::uint16_t index) const = 0;

        virtual std::uint16_t getBlendShapeChannelCount() const = 0;
        /**
            @brief Name of the requested blend shape channel.
            @param index
                A name's position in the zero-indexed array of blend shape channel names.
            @warning
                The index must be less than the value returned by BlendShapeChannelExtentReader::getBlendShapeChannelCount.
            @return View over the blend shape channel name string.
        */
        virtual StringView getBlendShapeChannelName(std::uint16_t index) const = 0;
        /**
            @brief Number of blend shape channel index lists.
            @note
                This value is useful only in the context of DefinitionWriter.
        */
        virtual std::uint16_t getBlendShapeChannelIndexListCount() const = 0;
        /**
            @brief List of blend shape channel indices for the specified LOD.
            @param lod
                The level of detail which blend shape channels are being requested.
            @warning
                The lod index must be less than the value returned by getLODCount.
            @return View over the blend shape channel indices.
            @warning
                These LOD indices are not interchangeable with the LOD values from BehaviorReader::getBlendShapeChannelLODs.
            @see getLODCount
            @see getBlendShapeChannelName
        */
        virtual ConstArrayView<std::uint16_t> getBlendShapeChannelIndicesForLOD(std::uint16_t lod) const = 0;

        virtual std::uint16_t getAnimatedMapCount() const = 0;
        /**
            @brief Name of the requested animated map.
            @param index
                A name's position in the zero-indexed array of animated map names.
            @warning
                The index must be less than the value returned by getAnimatedMapCount.
            @return View over the animated map name string.
        */
        virtual StringView getAnimatedMapName(std::uint16_t index) const = 0;
        /**
            @brief Number of animated map index lists.
            @note
                This value is useful only in the context of DefinitionWriter.
        */
        virtual std::uint16_t getAnimatedMapIndexListCount() const = 0;
        /**
            @brief List of animated map indices for the specified LOD.
            @param lod
                The level of detail which animated maps are being requested.
            @warning
                The lod index must be less than the value returned by getLODCount.
            @return View over the animated map indices.
            @see getLODCount
            @see getAnimatedMapName
        */
        virtual ConstArrayView<std::uint16_t> getAnimatedMapIndicesForLOD(std::uint16_t lod) const = 0;

        virtual std::uint16_t getMeshCount() const = 0;
        /**
            @brief Name of the requested mesh.
            @param index
                A name's position in the zero-indexed array of mesh names.
            @warning
                The index must be less than the value returned by getMeshCount.
            @return View over the mesh name string.
        */
        virtual StringView getMeshName(std::uint16_t index) const = 0;
        /**
            @brief Number of mesh index lists.
            @note
                This value is useful only in the context of DefinitionWriter.
        */
        virtual std::uint16_t getMeshIndexListCount() const = 0;
        /**
            @brief List of mesh indices for the specified LOD.
            @param lod
                The level of detail which meshes are being requested.
            @warning
                The lod index must be less than the value returned by getLODCount.
            @return View over the mesh indices.
            @see getLODCount
            @see getMeshName
        */
        virtual ConstArrayView<std::uint16_t> getMeshIndicesForLOD(std::uint16_t lod) const = 0;
        /**
            @brief Number of mesh-blend shape channel mapping items.
        */
        virtual std::uint16_t getMeshBlendShapeChannelMappingCount() const = 0;
        /**
            @param index
                A mapping's position in the zero-indexed array of mesh-blend shape channel mappings.
            @warning
                The index must be less than the value returned by getMeshBlendShapeChannelMappingCount.
            @return A structure holding the mesh index and the associated blend shape channel index.
        */
        virtual MeshBlendShapeChannelMapping getMeshBlendShapeChannelMapping(std::uint16_t index) const = 0;
        /**
            @brief List of mesh-blend shape channel mapping indices for the specified LOD.
            @note
                The indices from this list can be used with the getMeshBlendShapeChannelMapping API
                to retrieve individual mapping items.
            @param lod
                The level of detail which meshes are being requested.
            @warning
                The lod index must be less than the value returned by getLODCount.
            @return View over the mesh blend shape channel mapping indices.
            @see getLODCount
            @see getMeshBlendShapeChannelMapping
        */
        virtual ConstArrayView<std::uint16_t> getMeshBlendShapeChannelMappingIndicesForLOD(std::uint16_t lod) const = 0;
        /**
            @param index
                A joint's position in the zero-indexed array of joint translations.
            @warning
                The index must be less than the value returned by getJointCount.
            @return The joint's translation (x, y, z).
        */
        virtual Vector3 getNeutralJointTranslation(std::uint16_t index) const = 0;
        /**
            @brief List of all translation X values.
            @note
                This is an advanced API for performance critical access, for more convenient usage see getNeutralJointTranslation.
            @return View over all X values.
            @see getNeutralJointTranslation
        */
        virtual ConstArrayView<float> getNeutralJointTranslationXs() const = 0;
        /**
            @brief List of all translation Y values.
            @note
                This is an advanced API for performance critical access, for more convenient usage see getNeutralJointTranslation.
            @return View over all Y values.
            @see getNeutralJointTranslation
        */
        virtual ConstArrayView<float> getNeutralJointTranslationYs() const = 0;
        /**
            @brief List of all translation Z values.
            @note
                This is an advanced API for performance critical access, for more convenient usage see getNeutralJointTranslation.
            @return View over all Z values.
            @see getNeutralJointTranslation
        */
        virtual ConstArrayView<float> getNeutralJointTranslationZs() const = 0;
        /**
            @param index
                A joint's position in the zero-indexed array of joint rotations.
            @warning
                The index must be less than the value returned by getJointCount.
            @return The joint's rotation (x, y, z).
        */
        virtual Vector3 getNeutralJointRotation(std::uint16_t index) const = 0;
        /**
            @brief List of all rotation X values.
            @note
                This is an advanced API for performance critical access, for more convenient usage see getNeutralJointRotation.
            @return View over all X values.
            @see getNeutralJointRotation
        */
        virtual ConstArrayView<float> getNeutralJointRotationXs() const = 0;
        /**
            @brief List of all rotation Y values.
            @note
                This is an advanced API for performance critical access, for more convenient usage see getNeutralJointRotation.
            @return View over all Y values.
            @see getNeutralJointRotation
        */
        virtual ConstArrayView<float> getNeutralJointRotationYs() const = 0;
        /**
            @brief List of all rotation Z values.
            @note
                This is an advanced API for performance critical access, for more convenient usage see getNeutralJointRotation.
            @return View over all Z values.
            @see getNeutralJointRotation
        */
        virtual ConstArrayView<float> getNeutralJointRotationZs() const = 0;
};

}  // namespace dna