/******************************************************************************
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 * Copyright (c) 2013-2020, Esoteric Software LLC
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#ifndef SPINE_SKELETONTWOCOLORBATCH_H_
#define SPINE_SKELETONTWOCOLORBATCH_H_

#include "cocos2d.h"
#if COCOS2D_VERSION < 0x00040000

#include <spine/spine.h>
#include <vector>

namespace spine {
	struct V3F_C4B_C4B_T2F {
		cocos2d::Vec3 position;
		cocos2d::Color4B color;
		cocos2d::Color4B color2;
		cocos2d::Tex2F texCoords;
	};

	struct TwoColorTriangles {
		V3F_C4B_C4B_T2F* verts;
		unsigned short* indices;
		int vertCount;
		int indexCount;
	};

	class SP_API TwoColorTrianglesCommand : public cocos2d::CustomCommand {
	public:
		TwoColorTrianglesCommand();

		~TwoColorTrianglesCommand();

		void init(float globalOrder, GLuint textureID, cocos2d::GLProgramState* glProgramState, cocos2d::BlendFunc blendType, const TwoColorTriangles& triangles, const cocos2d::Mat4& mv, uint32_t flags);

		void useMaterial() const;

		inline uint32_t getMaterialID() const { return _materialID; }

		inline GLuint getTextureID() const { return _textureID; }

		inline const TwoColorTriangles& getTriangles() const { return _triangles; }

		inline ssize_t getVertexCount() const { return _triangles.vertCount; }

		inline ssize_t getIndexCount() const { return _triangles.indexCount; }

		inline const V3F_C4B_C4B_T2F* getVertices() const { return _triangles.verts; }

		inline const unsigned short* getIndices() const { return _triangles.indices; }

		inline cocos2d::GLProgramState* getGLProgramState() const { return _glProgramState; }

		inline cocos2d::BlendFunc getBlendType() const { return _blendType; }

		inline const cocos2d::Mat4& getModelView() const { return _mv; }

		void draw ();

		void setForceFlush (bool forceFlush) { _forceFlush = forceFlush; }

		bool isForceFlush () { return _forceFlush; };

	protected:
		void generateMaterialID();
		uint32_t _materialID;
		GLuint _textureID;
		cocos2d::GLProgramState* _glProgramState;
		cocos2d::GLProgram* _glProgram;
		cocos2d::BlendFunc _blendType;
		TwoColorTriangles _triangles;
		cocos2d::Mat4 _mv;
		GLuint _alphaTextureID;
		bool _forceFlush;
	};

	class SP_API SkeletonTwoColorBatch {
	public:
		static SkeletonTwoColorBatch* getInstance ();

		static void destroyInstance ();

		void update (float delta);

		V3F_C4B_C4B_T2F* allocateVertices(uint32_t numVertices);
		void deallocateVertices(uint32_t numVertices);

		unsigned short* allocateIndices(uint32_t numIndices);
		void deallocateIndices(uint32_t numIndices);

		TwoColorTrianglesCommand* addCommand(cocos2d::Renderer* renderer, float globalOrder, GLuint textureID, cocos2d::GLProgramState* glProgramState, cocos2d::BlendFunc blendType, const TwoColorTriangles& triangles, const cocos2d::Mat4& mv, uint32_t flags);

		cocos2d::GLProgramState* getTwoColorTintProgramState () { return _twoColorTintShaderState; }

		void batch (TwoColorTrianglesCommand* command);

		void flush (TwoColorTrianglesCommand* materialCommand);

		uint32_t getNumBatches () { return _numBatches; };

	protected:
		SkeletonTwoColorBatch ();
		virtual ~SkeletonTwoColorBatch ();

		void reset ();

		TwoColorTrianglesCommand* nextFreeCommand ();

		// pool of commands
		std::vector<TwoColorTrianglesCommand*> _commandsPool;
		uint32_t _nextFreeCommand;

		// pool of vertices
		std::vector<V3F_C4B_C4B_T2F> _vertices;
		uint32_t _numVertices;

		// pool of indices
		Vector<unsigned short> _indices;

		// two color tint shader and state
		cocos2d::GLProgram* _twoColorTintShader;
		cocos2d::GLProgramState* _twoColorTintShaderState;

		// VBO handles & attribute locations
		GLuint _vertexBufferHandle;
		V3F_C4B_C4B_T2F* _vertexBuffer;
		uint32_t _numVerticesBuffer;
		GLuint _indexBufferHandle;
		uint32_t _numIndicesBuffer;
		unsigned short* _indexBuffer;
		GLint _positionAttributeLocation;
		GLint _colorAttributeLocation;
		GLint _color2AttributeLocation;
		GLint _texCoordsAttributeLocation;

		// last batched command, needed for flushing to set material
		TwoColorTrianglesCommand* _lastCommand;

		// number of batches in the last frame
		uint32_t _numBatches;
	};
}

#endif

#endif // SPINE_SKELETONTWOCOLORBATCH_H_