/*
Crafter®.Graphics
Copyright (C) 2026 Catcrafts®
catcrafts.net

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License version 3.0 as published by the Free Software Foundation;

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
*/

module;
#ifdef CRAFTER_GRAPHICS_VULKAN
#include <vulkan/vulkan.h>
#endif
export module Crafter.Graphics:PipelineRTVulkan;
#ifdef CRAFTER_GRAPHICS_VULKAN
import std;
import :VulkanDevice;
import :DescriptorLayoutVulkan;

export namespace Crafter {
    template <typename Raygen, typename... Shaders>
    class PipelineRTVulkan {
        public:
        inline static VkPipeline pipeline;
        inline static VkPipelineLayout pipelineLayout;

        static void Init() {
            VkPipelineLayoutCreateInfo pipelineLayoutInfo {
                .sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO,
                .setLayoutCount = sizeof...(Shaders),
                .pSetLayouts = DescriptorLayoutVulkan<Shaders...>::descriptorSetLayout    
            };

			VulkanDevice::CheckVkResult(vkCreatePipelineLayout(VulkanDevice::device, &pipelineLayoutInfo, nullptr, &pipelineLayout));

			std::array<VkPipelineShaderStageCreateInfo, 1> shaderStages;

            shaderStages[0].sType  = VK_STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_CREATE_INFO;
            shaderStages[0].stage  = Raygen::_stage;
            shaderStages[0].module = Raygen::shader;
            shaderStages[0].pName  = Raygen::_entrypoint.value;
            shaderStages[0].flags = 0;
            shaderStages[0].pSpecializationInfo = nullptr;
            shaderStages[0].pNext = nullptr;

            VkRayTracingShaderGroupCreateInfoKHR group {
                .sType = VK_STRUCTURE_TYPE_RAY_TRACING_SHADER_GROUP_CREATE_INFO_KHR,
                .generalShader = 0,
                .closestHitShader = VK_SHADER_UNUSED_KHR,
                .anyHitShader = VK_SHADER_UNUSED_KHR,
                .intersectionShader = VK_SHADER_UNUSED_KHR
            };

            VkRayTracingPipelineCreateInfoKHR rtPipelineInfo{
                .sType = VK_STRUCTURE_TYPE_RAY_TRACING_PIPELINE_CREATE_INFO_KHR,
                .stageCount = static_cast<std::uint32_t>(shaderStages.size()),
                .pStages = shaderStages.data(),
                .groupCount = static_cast<std::uint32_t>(1),
                .pGroups = &group,
                .maxPipelineRayRecursionDepth = 1,
                .layout = pipelineLayout
            };

            VulkanDevice::vkCreateRayTracingPipelinesKHR(VulkanDevice::device, {}, {}, 1, &rtPipelineInfo, nullptr, &pipeline);
        }
    };
}

#endif