// Copyright (C) 2015 Jérôme Leclercq
// This file is part of the "Nazara Engine - Renderer module"
// For conditions of distribution and use, see copyright notice in Config.hpp

#include <Nazara/Renderer/RenderStates.hpp>
#include <Nazara/Core/Algorithm.hpp>
#include <Nazara/Math/Algorithm.hpp>
#include <functional>
#include <Nazara/Renderer/Debug.hpp>

namespace Nz
{
	bool operator==(const RenderStates& lhs, const RenderStates& rhs)
	{
		#define NazaraRenderStateMember(field) if (lhs.##field != rhs.##field) return false
		#define NazaraRenderStateBoolMember NazaraRenderStateMember
		#define NazaraRenderStateFloatMember(field, maxDiff) if (!NumberEquals(lhs.##field, rhs.##field, maxDiff)) return false

		NazaraRenderStateBoolMember(blending);
		NazaraRenderStateBoolMember(colorWrite);
		NazaraRenderStateBoolMember(depthBuffer);
		NazaraRenderStateBoolMember(faceCulling);
		NazaraRenderStateBoolMember(scissorTest);
		NazaraRenderStateBoolMember(stencilTest);

		if (lhs.depthBuffer)
			NazaraRenderStateBoolMember(depthWrite);

		NazaraRenderStateMember(faceFilling);

		if (lhs.blending) //< Remember, at this time we know lhs.blending == rhs.blending
		{
			NazaraRenderStateMember(dstBlend);
			NazaraRenderStateMember(srcBlend);
		}

		if (lhs.depthBuffer)
			NazaraRenderStateMember(depthFunc);

		if (lhs.faceCulling)
			NazaraRenderStateMember(cullingSide);

		if (lhs.stencilTest)
		{
			NazaraRenderStateMember(stencilCompare.back);
			NazaraRenderStateMember(stencilCompare.front);
			NazaraRenderStateMember(stencilCompareMask.back);
			NazaraRenderStateMember(stencilCompareMask.front);
			NazaraRenderStateMember(stencilDepthFail.back);
			NazaraRenderStateMember(stencilDepthFail.front);
			NazaraRenderStateMember(stencilFail.back);
			NazaraRenderStateMember(stencilFail.front);
			NazaraRenderStateMember(stencilPass.back);
			NazaraRenderStateMember(stencilPass.front);
			NazaraRenderStateMember(stencilReference.back);
			NazaraRenderStateMember(stencilReference.front);
			NazaraRenderStateMember(stencilWriteMask.back);
			NazaraRenderStateMember(stencilWriteMask.front);
		}

		NazaraRenderStateFloatMember(lineWidth, 0.001f);
		NazaraRenderStateFloatMember(pointSize, 0.001f);

		#undef NazaraRenderStateMember
		#undef NazaraRenderStateBoolMember
		#undef NazaraRenderStateFloatMember

		return true;
	}
}

namespace std
{
	template<>
	struct hash<Nz::RenderStates>
	{
		size_t operator()(const Nz::RenderStates& pipelineInfo) const
		{
			std::size_t seed = 0;

			Nz::UInt8 parameterHash = 0;
			Nz::UInt8 parameterIndex = 0;

			#define NazaraRenderStateMember(member) Nz::HashCombine(seed, pipelineInfo.##member)
			#define NazaraRenderStateBoolMember(member) parameterHash |= ((pipelineInfo.##member) ? 1U : 0U) << (parameterIndex++)
			#define NazaraRenderStateBoolMemberDep(dependency, member) parameterHash |= ((pipelineInfo.##dependency && pipelineInfo.##member) ? 1U : 0U) << (parameterIndex++)
			#define NazaraRenderStateFloatMember(member, maxDiff) Nz::HashCombine(seed, std::floor(pipelineInfo.##member / maxDiff) * maxDiff)

			NazaraRenderStateBoolMember(blending);
			NazaraRenderStateBoolMember(colorWrite);
			NazaraRenderStateBoolMember(depthBuffer);
			NazaraRenderStateBoolMember(faceCulling);
			NazaraRenderStateBoolMember(scissorTest);
			NazaraRenderStateBoolMember(stencilTest);

			NazaraRenderStateBoolMemberDep(depthBuffer, depthWrite);

			NazaraRenderStateMember(faceFilling);

			if (pipelineInfo.blending) //< Remember, at this time we know lhs.blending == rhs.blending
			{
				NazaraRenderStateMember(dstBlend);
				NazaraRenderStateMember(srcBlend);
			}

			if (pipelineInfo.depthBuffer)
				NazaraRenderStateMember(depthFunc);

			if (pipelineInfo.faceCulling)
				NazaraRenderStateMember(cullingSide);

			if (pipelineInfo.stencilTest)
			{
				NazaraRenderStateMember(stencilCompare.back);
				NazaraRenderStateMember(stencilCompare.front);
				NazaraRenderStateMember(stencilCompareMask.back);
				NazaraRenderStateMember(stencilCompareMask.front);
				NazaraRenderStateMember(stencilDepthFail.back);
				NazaraRenderStateMember(stencilDepthFail.front);
				NazaraRenderStateMember(stencilFail.back);
				NazaraRenderStateMember(stencilFail.front);
				NazaraRenderStateMember(stencilPass.back);
				NazaraRenderStateMember(stencilPass.front);
				NazaraRenderStateMember(stencilReference.back);
				NazaraRenderStateMember(stencilReference.front);
				NazaraRenderStateMember(stencilWriteMask.back);
				NazaraRenderStateMember(stencilWriteMask.front);
			}

			NazaraRenderStateFloatMember(lineWidth, 0.001f);
			NazaraRenderStateFloatMember(pointSize, 0.001f);

			#undef NazaraRenderStateMember
			#undef NazaraRenderStateBoolMember
			#undef NazaraRenderStateBoolMemberDep
			#undef NazaraRenderStateFloatMember

			Nz::HashCombine(seed, parameterHash);

			return seed;
		}
	};
}

#include <Nazara/Renderer/DebugOff.hpp>