// Copyright 2016 The SwiftShader Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//    http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef sw_VertexProcessor_hpp
#define sw_VertexProcessor_hpp

#include "Matrix.hpp"
#include "Context.hpp"
#include "RoutineCache.hpp"
#include "Pipeline/SpirvShader.hpp"

namespace sw
{
	struct DrawData;

	struct VertexCache   // FIXME: Variable size
	{
		void clear();

		Vertex vertex[16][4];
		unsigned int tag[16];

		int drawCall;
	};

	struct VertexTask
	{
		unsigned int vertexCount;
		unsigned int primitiveStart;
		VertexCache vertexCache;
	};

	class VertexProcessor
	{
	public:
		struct States
		{
			unsigned int computeHash();

			uint64_t shaderID;

			bool textureSampling           : 1;   // TODO: Eliminate by querying shader.
			unsigned char verticesPerPrimitive                : 2; // 1 (points), 2 (lines) or 3 (triangles)

			Sampler::State sampler[VERTEX_TEXTURE_IMAGE_UNITS];

			struct Input
			{
				operator bool() const   // Returns true if stream contains data
				{
					return count != 0;
				}

				StreamType type    : BITS(STREAMTYPE_LAST);
				unsigned int count : 3;
				bool normalized    : 1;
				unsigned int attribType : BITS(SpirvShader::ATTRIBTYPE_LAST);
			};

			Input input[MAX_VERTEX_INPUTS];
		};

		struct State : States
		{
			State();

			bool operator==(const State &state) const;

			unsigned int hash;
		};

		typedef void (*RoutinePointer)(Vertex *output, unsigned int *batch, VertexTask *vertexTask, DrawData *draw);

		VertexProcessor(Context *context);

		virtual ~VertexProcessor();

		void setInputStream(int index, const Stream &stream);
		void resetInputStreams();

		void setInstanceID(int instanceID);

	protected:
		const State update(DrawType drawType);
		Routine *routine(const State &state);

		void setRoutineCacheSize(int cacheSize);

	private:
		Context *const context;

		RoutineCache<State> *routineCache;
	};
}

#endif   // sw_VertexProcessor_hpp