#ifndef shaveGeometryOverride_h
#define shaveGeometryOverride_h
// Shave and a Haircut
// (c) 2019 Epic Games
// US Patent 6720962

#include <vector>

#include <maya/M3dView.h>
#include <maya/MColor.h>
#include <maya/MGeometryRequirements.h>
#include <maya/MGeometry.h>
#include <maya/MHWGeometry.h>
#include <maya/MMatrix.h>
#include <maya/MObject.h>
#include <maya/MPxGeometryOverride.h>
#include <maya/MShaderManager.h>
#include <maya/MTextureManager.h>
#include <maya/MUserData.h>
#include <maya/MVector.h>
#include <maya/MViewport2Renderer.h>

#include "shaveHairShape.h"

#if MAYA_API_VERSION < 20180000
class MDagPath;
#endif

class shaveInstanceDisplay;


class shaveGeometryOverride : public MHWRender::MPxGeometryOverride {
public:
	static MPxGeometryOverride* Creator(const MObject& obj)
	{
		return new shaveGeometryOverride(obj);
	}
	virtual ~shaveGeometryOverride();

	virtual MHWRender::DrawAPI supportedDrawAPIs() const;
	virtual void updateDG();
	
	virtual void updateRenderItems(
		const MDagPath& path,
		MHWRender::MRenderItemList& list);

	virtual void populateGeometry(
		const MHWRender::MGeometryRequirements& requirements,
		const MHWRender::MRenderItemList& renderItems,
		MHWRender::MGeometry& data
	);

#if MAYA_API_VERSION >= 201600
	virtual void updateSelectionGranularity(const MDagPath& path, MHWRender::MSelectionContext& selectCtx);
#endif
	virtual void cleanUp();

#if MAYA_API_VERSION >= 201600
	static MStatus registerComponentConverters();
	static MStatus deregisterComponentConverters();
#endif

	//	Custom user data to attach to render items
	//	for doing selection.
	//
	class SelectionData : public MUserData
	{
	public:
		SelectionData()
		: MUserData(false)
		{}

		virtual ~SelectionData()
		{}

		MString mShaveSelectType;

		//	Holds the encoded (guide, vert) value for each
		//	primitive used to draw guide verts.
		//
		std::vector<unsigned int> mPrimIdxToVertIdx;

		//	Holds the guide index for each primitive used to
		//	draw a guide.
		//
		std::vector<unsigned int> mPrimIdxToGuideIdx;
	};

	//	RenderItem names.
	//
	static const MString kHairShadedItemName;
	static const MString kHairShadedSelectedItemName;
	static const MString kHairWireItemName;
	static const MString kHairWireSelectedItemName;
	static const MString kInstanceShadedItemName;
	static const MString kInstanceWireItemName;
	static const MString kInstanceWireSelectedItemName;
	static const MString kGuidesItemName;
	static const MString kKnotsItemName;

protected:
	shaveGeometryOverride(const MObject& obj);

	bool disableRenderItem(
		MHWRender::MRenderItemList& list,
		const MString& itemName,
		MHWRender::MGeometry::Primitive primType,
		MHWRender::MGeometry::DrawMode drawMode
	);

	virtual void populateHairInstances(
		const MHWRender::MGeometryRequirements& requirements,
        const MHWRender::MRenderItemList& renderItems,
		MHWRender::MGeometry& data
		);


	//uses geometry shader
	virtual void populateHairLines(
		const MHWRender::MGeometryRequirements& requirements,
        const MHWRender::MRenderItemList& renderItems,
		MHWRender::MGeometry& data
		);


	//polygonal hair
	virtual void populateHairPolys(
		const MHWRender::MGeometryRequirements& requirements,
        const MHWRender::MRenderItemList& renderItems,
		MHWRender::MGeometry& data
		);


	//uses geometry shader
	virtual void populateHairGuides(
		const MHWRender::MGeometryRequirements& requirements,
        const MHWRender::MRenderItemList& renderItems,
		MHWRender::MGeometry& data
		);

	void cacheHairPolys();
	void cacheGuidePolys();
	void cacheKnotPolys();

	shaveHairShape* shave;
	MObject			shobj;

	struct Poly {
		MVector t[3];
		MVector v[3];
		MColor  c[3];
		MVector uv[3];
	};

	class PolyGroup {
	public:
		std::vector<Poly> p;
	};
	std::vector<PolyGroup> groups;
	unsigned int ingroups;

	struct GuidePoly {
		MVector v[3];
		bool active;
	};
	std::vector<GuidePoly> guidePolys;

	struct KnotPoly {
		MVector v[3];
		bool active;
	};
	std::vector<KnotPoly> knotPolys;

	MHWRender::MTexture* instex;

	SelectionData mSelectionData;

	//	We're only allowed to access the DG during updateDG(). Below
	//	are the DG-dependent data that we need to cache for use in subsequent
	//	methods.
	//
	unsigned int mNumHairsToDraw;
	const shaveHairShape::DisplayHairCache* mHairCache;
	M3dView::LightingMode mLightMode;
	int mHairDisplayMode;
	MColor mSpecularTint;
	MColor mSpecularTint2;
	float mGloss;
	float mSpecular;
	const shaveInstanceDisplay* mInstanceCache;
	MMatrix mWorldToCam;
	MVector mViewDir;
	MVector mUpDir;
	MVector mRightDir;
	float mTransparency;
	bool mDoTipFade;
	int mPasses;
	const shaveHairShape::Guides* mGuideCache;
	float mGuideExtent;
};

#endif