// Copyright (C) 2020 Jérôme Leclercq
// This file is part of the "Nazara Engine - Renderer module"
// For conditions of distribution and use, see copyright notice in Config.hpp

#pragma once

#ifndef NAZARA_SHADER_AST_HPP
#define NAZARA_SHADER_AST_HPP

#include <Nazara/Prerequisites.hpp>
#include <Nazara/Shader/ShaderExpressionType.hpp>
#include <Nazara/Shader/ShaderNodes.hpp>
#include <Nazara/Utility/Enums.hpp>
#include <optional>
#include <unordered_map>
#include <vector>

namespace Nz
{
	class NAZARA_SHADER_API ShaderAst
	{
		public:
			struct Function;
			struct FunctionParameter;
			struct InputOutput;
			struct Struct;
			struct StructMember;
			struct Uniform;
			struct VariableBase;

			inline ShaderAst(ShaderStageType shaderStage);
			ShaderAst(const ShaderAst&) = default;
			ShaderAst(ShaderAst&&) = default;
			~ShaderAst() = default;

			void AddFunction(std::string name, ShaderNodes::StatementPtr statement, std::vector<FunctionParameter> parameters = {}, ShaderNodes::BasicType returnType = ShaderNodes::BasicType::Void);
			void AddInput(std::string name, ShaderExpressionType type, std::optional<std::size_t> locationIndex = {});
			void AddOutput(std::string name, ShaderExpressionType type, std::optional<std::size_t> locationIndex = {});
			void AddStruct(std::string name, std::vector<StructMember> members);
			void AddUniform(std::string name, ShaderExpressionType type, std::optional<std::size_t> bindingIndex = {}, std::optional<ShaderNodes::MemoryLayout> memoryLayout = {});

			inline const Function& GetFunction(std::size_t i) const;
			inline std::size_t GetFunctionCount() const;
			inline const std::vector<Function>& GetFunctions() const;
			inline const InputOutput& GetInput(std::size_t i) const;
			inline std::size_t GetInputCount() const;
			inline const std::vector<InputOutput>& GetInputs() const;
			inline const InputOutput& GetOutput(std::size_t i) const;
			inline std::size_t GetOutputCount() const;
			inline const std::vector<InputOutput>& GetOutputs() const;
			inline ShaderStageType GetStage() const;
			inline const Struct& GetStruct(std::size_t i) const;
			inline std::size_t GetStructCount() const;
			inline const std::vector<Struct>& GetStructs() const;
			inline const Uniform& GetUniform(std::size_t i) const;
			inline std::size_t GetUniformCount() const;
			inline const std::vector<Uniform>& GetUniforms() const;

			ShaderAst& operator=(const ShaderAst&) = default;
			ShaderAst& operator=(ShaderAst&&) = default;

			struct VariableBase
			{
				std::string name;
				ShaderExpressionType type;
			};

			struct FunctionParameter : VariableBase
			{
			};

			struct Function
			{
				std::string name;
				std::vector<FunctionParameter> parameters;
				ShaderNodes::BasicType returnType;
				ShaderNodes::StatementPtr statement;
			};

			struct InputOutput : VariableBase
			{
				std::optional<std::size_t> locationIndex;
			};

			struct Uniform : VariableBase
			{
				std::optional<std::size_t> bindingIndex;
				std::optional<ShaderNodes::MemoryLayout> memoryLayout;
			};

			struct Struct
			{
				std::string name;
				std::vector<StructMember> members;
			};

			struct StructMember
			{
				std::string name;
				ShaderExpressionType type;
			};

		private:
			std::vector<Function> m_functions;
			std::vector<InputOutput> m_inputs;
			std::vector<InputOutput> m_outputs;
			std::vector<Struct> m_structs;
			std::vector<Uniform> m_uniforms;
			ShaderStageType m_stage;
	};
}

#include <Nazara/Shader/ShaderAst.inl>

#endif // NAZARA_SHADER_AST_HPP