// Copyright 2020 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 vk_Context_hpp
#define vk_Context_hpp

#include "Config.hpp"
#include "Memset.hpp"
#include "Stream.hpp"
#include "System/Types.hpp"
#include "Vulkan/VkDescriptorSet.hpp"

#include <vector>

namespace vk {

class Buffer;
class Device;
class ImageView;
class PipelineLayout;

struct VertexInputBinding
{
	Buffer *buffer;
	VkDeviceSize offset;
};

struct IndexBuffer
{
	inline VkIndexType getIndexType() const { return indexType; }
	void setIndexBufferBinding(const VertexInputBinding &indexBufferBinding, VkIndexType type);
	void getIndexBuffers(VkPrimitiveTopology topology, uint32_t count, uint32_t first, bool indexed, bool hasPrimitiveRestartEnable, std::vector<std::pair<uint32_t, void *>> *indexBuffers) const;

private:
	int bytesPerIndex() const;

	VertexInputBinding binding;
	VkIndexType indexType;
};

struct Attachments
{
	ImageView *renderTarget[sw::RENDERTARGETS] = {};
	ImageView *depthBuffer = nullptr;
	ImageView *stencilBuffer = nullptr;

	bool isColorClamped(int index) const;
	VkFormat renderTargetInternalFormat(int index) const;
};

struct Inputs
{
	Inputs(const VkPipelineVertexInputStateCreateInfo *vertexInputState);

	void updateDescriptorSets(const DescriptorSet::Array &dso,
	                          const DescriptorSet::Bindings &ds,
	                          const DescriptorSet::DynamicOffsets &ddo);
	inline const DescriptorSet::Array &getDescriptorSetObjects() const { return descriptorSetObjects; }
	inline const DescriptorSet::Bindings &getDescriptorSets() const { return descriptorSets; }
	inline const DescriptorSet::DynamicOffsets &getDescriptorDynamicOffsets() const { return descriptorDynamicOffsets; }
	inline const sw::Stream &getStream(uint32_t i) const { return stream[i]; }

	void bindVertexInputs(int firstInstance);
	void setVertexInputBinding(const VertexInputBinding vertexInputBindings[]);
	void advanceInstanceAttributes();

private:
	VertexInputBinding vertexInputBindings[MAX_VERTEX_INPUT_BINDINGS] = {};
	DescriptorSet::Array descriptorSetObjects = {};
	DescriptorSet::Bindings descriptorSets = {};
	DescriptorSet::DynamicOffsets descriptorDynamicOffsets = {};
	sw::Stream stream[sw::MAX_INTERFACE_COMPONENTS / 4];
};

struct BlendState : sw::Memset<BlendState>
{
	BlendState()
	    : Memset(this, 0)
	{}

	BlendState(bool alphaBlendEnable,
	           VkBlendFactor sourceBlendFactor,
	           VkBlendFactor destBlendFactor,
	           VkBlendOp blendOperation,
	           VkBlendFactor sourceBlendFactorAlpha,
	           VkBlendFactor destBlendFactorAlpha,
	           VkBlendOp blendOperationAlpha)
	    : Memset(this, 0)
	    , alphaBlendEnable(alphaBlendEnable)
	    , sourceBlendFactor(sourceBlendFactor)
	    , destBlendFactor(destBlendFactor)
	    , blendOperation(blendOperation)
	    , sourceBlendFactorAlpha(sourceBlendFactorAlpha)
	    , destBlendFactorAlpha(destBlendFactorAlpha)
	    , blendOperationAlpha(blendOperationAlpha)
	{}

	bool alphaBlendEnable;
	VkBlendFactor sourceBlendFactor;
	VkBlendFactor destBlendFactor;
	VkBlendOp blendOperation;
	VkBlendFactor sourceBlendFactorAlpha;
	VkBlendFactor destBlendFactorAlpha;
	VkBlendOp blendOperationAlpha;
};

struct DynamicState
{
	VkViewport viewport;
	VkRect2D scissor;
	sw::float4 blendConstants;
	float depthBiasConstantFactor = 0.0f;
	float depthBiasClamp = 0.0f;
	float depthBiasSlopeFactor = 0.0f;
	float minDepthBounds = 0.0f;
	float maxDepthBounds = 0.0f;

	uint32_t compareMask[2] = { 0 };
	uint32_t writeMask[2] = { 0 };
	uint32_t reference[2] = { 0 };
};

struct GraphicsState
{
	GraphicsState(const Device *device, const VkGraphicsPipelineCreateInfo *pCreateInfo, const PipelineLayout *layout, bool robustBufferAccess);

	const GraphicsState combineStates(const DynamicState &dynamicState) const;

	inline const PipelineLayout *getPipelineLayout() const { return pipelineLayout; }
	inline bool getRobustBufferAccess() const { return robustBufferAccess; }
	inline VkPrimitiveTopology getTopology() const { return topology; }

	inline VkProvokingVertexModeEXT getProvokingVertexMode() const { return provokingVertexMode; }

	inline VkStencilOpState getFrontStencil() const { return frontStencil; }
	inline VkStencilOpState getBackStencil() const { return backStencil; }

	// Pixel processor states
	inline VkCullModeFlags getCullMode() const { return cullMode; }
	inline VkFrontFace getFrontFace() const { return frontFace; }
	inline VkPolygonMode getPolygonMode() const { return polygonMode; }
	inline VkLineRasterizationModeEXT getLineRasterizationMode() const { return lineRasterizationMode; }

	inline float getConstantDepthBias() const { return constantDepthBias; }
	inline float getSlopeDepthBias() const { return slopeDepthBias; }
	inline float getDepthBiasClamp() const { return depthBiasClamp; }
	inline bool hasDepthRangeUnrestricted() const { return depthRangeUnrestricted; }

	// Pixel processor states
	inline bool hasRasterizerDiscard() const { return rasterizerDiscard; }
	inline VkCompareOp getDepthCompareMode() const { return depthCompareMode; }

	inline float getLineWidth() const { return lineWidth; }

	inline unsigned int getMultiSampleMask() const { return multiSampleMask; }
	inline int getSampleCount() const { return sampleCount; }
	inline bool hasSampleShadingEnabled() const { return sampleShadingEnable; }
	inline float getMinSampleShading() const { return minSampleShading; }
	inline bool hasAlphaToCoverage() const { return alphaToCoverage; }

	inline bool hasPrimitiveRestartEnable() const { return primitiveRestartEnable; }
	inline const VkRect2D &getScissor() const { return scissor; }
	inline const VkViewport &getViewport() const { return viewport; }
	inline const sw::float4 &getBlendConstants() const { return blendConstants; }

	bool isDrawPoint(bool polygonModeAware) const;
	bool isDrawLine(bool polygonModeAware) const;
	bool isDrawTriangle(bool polygonModeAware) const;

	BlendState getBlendState(int index, const Attachments &attachments, bool fragmentContainsKill) const;

	int colorWriteActive(int index, const Attachments &attachments) const;
	bool depthWriteActive(const Attachments &attachments) const;
	bool depthBufferActive(const Attachments &attachments) const;
	bool stencilActive(const Attachments &attachments) const;

private:
	inline bool hasDynamicState(VkDynamicState dynamicState) const { return (dynamicStateFlags & (1 << dynamicState)) != 0; }

	VkBlendFactor sourceBlendFactor(int index) const;
	VkBlendFactor destBlendFactor(int index) const;
	VkBlendOp blendOperation(int index, const Attachments &attachments) const;

	VkBlendFactor sourceBlendFactorAlpha(int index) const;
	VkBlendFactor destBlendFactorAlpha(int index) const;
	VkBlendOp blendOperationAlpha(int index, const Attachments &attachments) const;

	bool alphaBlendActive(int index, const Attachments &attachments, bool fragmentContainsKill) const;
	bool colorWriteActive(const Attachments &attachments) const;

	const PipelineLayout *pipelineLayout;
	const bool robustBufferAccess = true;
	uint32_t dynamicStateFlags = 0;
	VkPrimitiveTopology topology;

	VkProvokingVertexModeEXT provokingVertexMode;

	bool stencilEnable;
	VkStencilOpState frontStencil;
	VkStencilOpState backStencil;

	// Pixel processor states
	VkCullModeFlags cullMode;
	VkFrontFace frontFace;
	VkPolygonMode polygonMode;
	VkLineRasterizationModeEXT lineRasterizationMode;

	float constantDepthBias;
	float slopeDepthBias;
	float depthBiasClamp;
	bool depthRangeUnrestricted;

	// Pixel processor states
	bool rasterizerDiscard;
	bool depthBoundsTestEnable;
	bool depthBufferEnable;
	VkCompareOp depthCompareMode;
	bool depthWriteEnable;

	float lineWidth;

	int colorWriteMask[sw::RENDERTARGETS];  // RGBA
	unsigned int multiSampleMask;
	int sampleCount;
	bool alphaToCoverage;

	bool sampleShadingEnable = false;
	float minSampleShading = 0.0f;

	bool primitiveRestartEnable = false;
	VkRect2D scissor;
	VkViewport viewport;
	sw::float4 blendConstants;

	BlendState blendState[sw::RENDERTARGETS];
};

}  // namespace vk

#endif  // vk_Context_hpp