/*
* Copyright (c) <2017> Side Effects Software Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/

#pragma once
#include "HoudiniGeoPartObject.h"
#include "HoudiniAssetInstanceInput.h"
#include "HoudiniAssetInstanceInputField.generated.h"

class UStaticMesh;
class UMaterialInterface;
class UHoudiniAssetComponent;

UCLASS()
class HOUDINIENGINERUNTIME_API UHoudiniAssetInstanceInputField : public UObject
{
    friend class UHoudiniAssetInstanceInput;

    GENERATED_UCLASS_BODY()

    public:

        /** Create an instance of input field. **/
        static UHoudiniAssetInstanceInputField * Create(
            UObject * InPrimaryObject,
            UHoudiniAssetInstanceInput * InHoudiniAssetInstanceInput,
            const FHoudiniGeoPartObject & HoudiniGeoPartObject );

        /** Create an instance of input field from another input field. **/
        static UHoudiniAssetInstanceInputField * Create(
            UObject * InPrimaryObject,
            const UHoudiniAssetInstanceInputField * OtherInputField );

    /** UObject methods. **/
    public:

        virtual void Serialize( FArchive & Ar ) override;
        static void AddReferencedObjects( UObject * InThis, FReferenceCollector & Collector );
        virtual void BeginDestroy() override;

#if WITH_EDITOR

        virtual void PostEditUndo() override;

#endif

    public:

        /** Return geo part object associated with this field. **/
        const FHoudiniGeoPartObject & GetHoudiniGeoPartObject() const;

        /** Refresh state based on the given geo part object */
        void SetGeoPartObject( const FHoudiniGeoPartObject & InHoudiniGeoPartObject );

        /** Return original static mesh. **/
        UObject* GetOriginalObject() const;

        /** Return the static mesh associated with an instance variation. **/
        UObject * GetInstanceVariation( int32 VariationIndex ) const;  

        /** Add a variation to the instancing. **/
        void AddInstanceVariation( UObject * InstancedObject, int32 VariationIdx );

        /** Replace the instance variation in a particular slot. **/
        void ReplaceInstanceVariation( UObject * InObject, int32 Index );

        /** Remove a variation from instancing **/
        void RemoveInstanceVariation( int32 VariationIdx );

        /** Returns the number of instance variations. **/
        int32 InstanceVariationCount() const;

        /** Given a static mesh, find which slot(s) it occupies in the instance variations. **/
        void FindObjectIndices( UObject * InStaticMesh, TArray< int32 > & Indices );

        /** Get material replacements. **/
        bool GetMaterialReplacementMeshes(
            UMaterialInterface * Material,
            TMap< UStaticMesh *, int32 > & MaterialReplacementsMap );

        /** After duplicating this field we need to fix up the referenced external objects */
        void FixInstancedObjects( const TMap<UObject*, UObject*>& ReplacementMap );

        /** Get rotator used by this field. **/
        const FRotator & GetRotationOffset( int32 VariationIdx ) const;

        /** Set rotation offset used by this field. **/
        void SetRotationOffset( const FRotator & Rotator, int32 VariationIdx );

        /** Get scale used by this field. **/
        const FVector & GetScaleOffset( int32 VariationIdx ) const;

        /** Set scale used by this field. **/
        void SetScaleOffset( const FVector & InScale, int32 VariationIdx );

        /** Return true if all fields are scaled linearly. **/
        bool AreOffsetsScaledLinearly( int32 VariationIdx ) const;

        /** Set whether offsets are scaled linearly. **/
        void SetLinearOffsetScale( bool bEnabled, int32 VariationIdx );

        /** Return true if original static mesh is used. **/
        bool IsOriginalObjectUsed( int32 VariationIdx ) const;

        /** Return corresponding instanced static mesh component. **/
        class USceneComponent * GetInstancedComponent( int32 VariationIdx ) const;

        /** Return transformations of all instances used by the variation **/
        const TArray< FTransform > & GetInstancedTransforms( int32 VariationIdx ) const;

        /** Return the array of transforms for all variations **/
        FORCEINLINE const TArray< FTransform > & GetInstancedTransforms() { return InstancedTransforms; }

        /** Return transformations of all instances used by the variation **/
        FORCEINLINE const TArray< FLinearColor > & GetInstancedColors(int32 VariationIdx) const { return VariationInstanceColorOverrideArray[VariationIdx]; }

        /** Return the array of transforms for all variations **/
        FORCEINLINE const TArray< FLinearColor > & GetInstancedColors() { return InstanceColorOverride; }

        /** Return the array of processed transforms **/
        void GetProcessedTransforms(TArray<FTransform>& ProcessedTransform, const int32& VariationIdx) const;

        /** Recreates render states for instanced static mesh component. **/
        void RecreateRenderState();

        /** Recreates physics states for instanced static mesh component. **/
        void RecreatePhysicsState();

        /** Updates the uproperty attributes for the generated instanced components **/
        void UpdateInstanceUPropertyAttributes();

    protected:

        /** Create instanced component for this field. **/
        void AddInstanceComponent( int32 VariationIdx );

        /** Set transforms for this field. **/
        void SetInstanceTransforms( const TArray< FTransform > & ObjectTransforms );

        /** Update relative transform for this field. **/
        void UpdateRelativeTransform();

        /** Update instance transformations. **/
        void UpdateInstanceTransforms( bool RecomputeVariationAssignments );

    protected:

        /** Original object used by the instancer. **/
        UObject* OriginalObject;
        
        /** Currently used Objects */
        TArray< UObject* > InstancedObjects;
        
        /** Used instanced actor component. **/
        TArray< USceneComponent * > InstancerComponents;

        /** Parent Houdini asset component. **/
        UObject * HoudiniAssetComponent;

        /** Owner input. **/
        UHoudiniAssetInstanceInput * HoudiniAssetInstanceInput;

        /** Transforms, one for each instance. **/
        TArray< FTransform > InstancedTransforms;

        /** Assignment of Transforms to each variation **/
        TArray< TArray< FTransform > > VariationTransformsArray;

        /** Color overrides, one per instance **/
        TArray<FLinearColor> InstanceColorOverride;

        /** Per-variation color override assignments */
        TArray< TArray< FLinearColor > > VariationInstanceColorOverrideArray;

        /** Corresponding geo part object. **/
        FHoudiniGeoPartObject HoudiniGeoPartObject;

        /** Rotation offset for instanced component. **/
        TArray< FRotator > RotationOffsets;

        /** Scale offset for instanced component. **/
        TArray< FVector > ScaleOffsets;

        /** Whether to scale linearly for all fields. **/
        TArray< bool > bScaleOffsetsLinearlyArray;

        /** Flags used by this input field. **/
        uint32 HoudiniAssetInstanceInputFieldFlagsPacked;
};

/** Functor used to sort instance input fields. **/
struct HOUDINIENGINERUNTIME_API FHoudiniAssetInstanceInputFieldSortPredicate
{
    bool operator()( const UHoudiniAssetInstanceInputField & A, const UHoudiniAssetInstanceInputField & B ) const;
};