// 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.

#include "VertexProgram.hpp"

#include "SamplerCore.hpp"
#include "Device/Renderer.hpp"
#include "Device/Vertex.hpp"
#include "System/Half.hpp"
#include "Vulkan/VkDebug.hpp"

#include "Vulkan/VkPipelineLayout.hpp"

namespace sw {

VertexProgram::VertexProgram(
		const VertexProcessor::State &state,
		vk::PipelineLayout const *pipelineLayout,
		SpirvShader const *spirvShader,
		const vk::DescriptorSet::Bindings &descriptorSets)
	: VertexRoutine(state, pipelineLayout, spirvShader),
	  descriptorSets(descriptorSets)
{
	routine.setImmutableInputBuiltins(spirvShader);

	routine.setInputBuiltin(spirvShader, spv::BuiltInViewIndex, [&](const SpirvShader::BuiltinMapping& builtin, Array<SIMD::Float>& value)
	{
		assert(builtin.SizeInComponents == 1);
		value[builtin.FirstComponent] = As<Float4>(Int4((*Pointer<Int>(data + OFFSET(DrawData, viewID)))));
	});

	routine.setInputBuiltin(spirvShader, spv::BuiltInInstanceIndex, [&](const SpirvShader::BuiltinMapping& builtin, Array<SIMD::Float>& value)
	{
		// TODO: we could do better here; we know InstanceIndex is uniform across all lanes
		assert(builtin.SizeInComponents == 1);
		value[builtin.FirstComponent] = As<Float4>(Int4((*Pointer<Int>(data + OFFSET(DrawData, instanceID)))));
	});

	routine.setInputBuiltin(spirvShader, spv::BuiltInSubgroupSize, [&](const SpirvShader::BuiltinMapping& builtin, Array<SIMD::Float>& value)
	{
		ASSERT(builtin.SizeInComponents == 1);
		value[builtin.FirstComponent] = As<SIMD::Float>(SIMD::Int(SIMD::Width));
	});

	routine.descriptorSets = data + OFFSET(DrawData, descriptorSets);
	routine.descriptorDynamicOffsets = data + OFFSET(DrawData, descriptorDynamicOffsets);
	routine.pushConstants = data + OFFSET(DrawData, pushConstants);
	routine.constants = *Pointer<Pointer<Byte>>(data + OFFSET(DrawData, constants));
}

VertexProgram::~VertexProgram()
{
}

void VertexProgram::program(Pointer<UInt> &batch, UInt& vertexCount)
{
	auto it = spirvShader->inputBuiltins.find(spv::BuiltInVertexIndex);
	if(it != spirvShader->inputBuiltins.end())
	{
		assert(it->second.SizeInComponents == 1);

		routine.getVariable(it->second.Id)[it->second.FirstComponent] =
				As<Float4>(*Pointer<Int4>(As<Pointer<Int4>>(batch)) +
				           Int4(*Pointer<Int>(data + OFFSET(DrawData, baseVertex))));
	}

	auto activeLaneMask = SIMD::Int(0xFFFFFFFF);
	Int4 storesAndAtomicsMask = CmpGE(UInt4(vertexCount), UInt4(1, 2, 3, 4));
	spirvShader->emit(&routine, activeLaneMask, storesAndAtomicsMask, descriptorSets);

	spirvShader->emitEpilog(&routine);
}

}  // namepsace sw