#include "BasePass.h"
#include "Graphics/Enums.h"
#include "Graphics/Graphics.h"
#include "Graphics/Initializer.h"
#include "Graphics/Shader.h"
#include "Window/Window.h"
#include "Component/Camera.h"
#include "Component/Mesh.h"
#include "Actor/CameraActor.h"
#include "Math/Vector.h"
#include "RenderGraph.h"
#include "Material/MaterialInstance.h"
#include "Graphics/Descriptor.h"
#include "Graphics/Command.h"
#include "Graphics/StaticMeshVertexData.h"

using namespace Seele;

extern bool useViewCulling;

BasePass::BasePass(Gfx::PGraphics graphics, PScene scene)
    : RenderPass(graphics, scene)
{
    basePassLayout = graphics->createPipelineLayout("BasePassLayout");

    basePassLayout->addDescriptorLayout(viewParamsLayout);
    basePassLayout->addDescriptorLayout(scene->getLightEnvironment()->getDescriptorLayout());

    lightCullingLayout = graphics->createDescriptorLayout("pLightCullingData");
    // oLightIndexList
    lightCullingLayout->addDescriptorBinding(Gfx::DescriptorBinding{ .binding = 0, .descriptorType = Gfx::SE_DESCRIPTOR_TYPE_STORAGE_BUFFER, });
    // oLightGrid
    lightCullingLayout->addDescriptorBinding(Gfx::DescriptorBinding{ .binding = 1, .descriptorType = Gfx::SE_DESCRIPTOR_TYPE_STORAGE_IMAGE, });
    lightCullingLayout->create();

    basePassLayout->addDescriptorLayout(lightCullingLayout);
    basePassLayout->addPushConstants(Gfx::SePushConstantRange{
        .stageFlags = Gfx::SE_SHADER_STAGE_TASK_BIT_EXT | Gfx::SE_SHADER_STAGE_VERTEX_BIT,
        .offset = 0,
        .size = sizeof(VertexData::DrawCallOffsets),
        });

    if (graphics->supportMeshShading())
    {
        graphics->getShaderCompiler()->registerRenderPass("BasePass", Gfx::PassConfig {
            .baseLayout = basePassLayout,  
            .taskFile = "DrawListTask",
            .mainFile = "DrawListMesh", 
            .fragmentFile = "BasePass",
            .hasFragmentShader = true,
            .useMeshShading = true,
            .hasTaskShader = true,
            .useMaterial = true, 
            .useVisibility = false,
            });
    }
    else
    {
        graphics->getShaderCompiler()->registerRenderPass("BasePass", Gfx::PassConfig {
            .baseLayout = basePassLayout,  
            .taskFile = "",
            .mainFile = "LegacyPass", 
            .fragmentFile = "BasePass",
            .hasFragmentShader = true,
            .useMeshShading = false,
            .hasTaskShader = false,
            .useMaterial = true, 
            .useVisibility = false,
            });
    }
}

BasePass::~BasePass()
{
}

void BasePass::beginFrame(const Component::Camera& cam)
{
    RenderPass::beginFrame(cam);

    lightCullingLayout->reset();
    opaqueCulling = lightCullingLayout->allocateDescriptorSet();
    transparentCulling = lightCullingLayout->allocateDescriptorSet();
}

void BasePass::render()
{
    opaqueCulling->updateBuffer(0, oLightIndexList);
    opaqueCulling->updateTexture(1, oLightGrid);
    transparentCulling->updateBuffer(0, tLightIndexList);
    transparentCulling->updateTexture(1, tLightGrid);
    opaqueCulling->writeChanges();
    transparentCulling->writeChanges();

    graphics->beginRenderPass(renderPass);
    Array<Gfx::ORenderCommand> commands;

    Gfx::ShaderPermutation permutation = graphics->getShaderCompiler()->getTemplate("BasePass");
    permutation.setViewCulling(useViewCulling);
    for (VertexData* vertexData : VertexData::getList())
    {
        vertexData->getInstanceDataSet()->updateBuffer(6, cullingBuffer);
        vertexData->getInstanceDataSet()->writeChanges();
        permutation.setVertexData(vertexData->getTypeName());
        const auto& materials = vertexData->getMaterialData();
        for (const auto& materialData : materials)
        {
            // material not used for any active meshes, skip
            if (materialData.instances.size() == 0)
                continue;
            // Create Pipeline(Material, VertexData)
            // Descriptors:
            // ViewData => global, static
            // VertexData => per meshtype
            // SceneData => per material instance
            // LightEnv => provided by scene
            // Material => per material
            // LightCulling => calculated by pass
            permutation.setMaterial(materialData.material->getName());
            Gfx::PermutationId id(permutation);

            Gfx::ORenderCommand command = graphics->createRenderCommand("BaseRender");
            command->setViewport(viewport);

            const Gfx::ShaderCollection* collection = graphics->getShaderCompiler()->findShaders(id);
            assert(collection != nullptr);
            if (graphics->supportMeshShading())
            {
                Gfx::MeshPipelineCreateInfo pipelineInfo = {
                    .taskShader = collection->taskShader,
                    .meshShader = collection->meshShader,
                    .fragmentShader = collection->fragmentShader,
                    .renderPass = renderPass,
                    .pipelineLayout = collection->pipelineLayout,
                    .multisampleState = {
                        .samples = viewport->getSamples(),
                    },
                    .depthStencilState = {
                        .depthCompareOp = Gfx::SE_COMPARE_OP_GREATER_OR_EQUAL,
                    },
                    .colorBlend = {
                        .attachmentCount = 1,
                    },
                };
                Gfx::PGraphicsPipeline pipeline = graphics->createGraphicsPipeline(std::move(pipelineInfo));
                command->bindPipeline(pipeline);
            }
            else
            {
                Gfx::LegacyPipelineCreateInfo pipelineInfo = {
                    .vertexShader = collection->vertexShader,
                    .fragmentShader = collection->fragmentShader,
                    .renderPass = renderPass,
                    .pipelineLayout = collection->pipelineLayout,
                    .multisampleState = {
                        .samples = viewport->getSamples(),
                    },
                    .depthStencilState = {
                        .depthCompareOp = Gfx::SE_COMPARE_OP_GREATER_OR_EQUAL,
                    },
                    .colorBlend = {
                        .attachmentCount = 1,
                    },
                };
                Gfx::PGraphicsPipeline pipeline = graphics->createGraphicsPipeline(std::move(pipelineInfo));
                command->bindPipeline(pipeline);
            }
            command->bindDescriptor(viewParamsSet);
            command->bindDescriptor(vertexData->getVertexDataSet());
            command->bindDescriptor(vertexData->getInstanceDataSet());
            command->bindDescriptor(scene->getLightEnvironment()->getDescriptorSet());
            command->bindDescriptor(opaqueCulling);
            for (const auto& drawCall : materialData.instances)
            {
                command->bindDescriptor(drawCall.materialInstance->getDescriptorSet());
                command->pushConstants(Gfx::SE_SHADER_STAGE_TASK_BIT_EXT | Gfx::SE_SHADER_STAGE_VERTEX_BIT, 0, sizeof(VertexData::DrawCallOffsets), &drawCall.offsets);
                if (graphics->supportMeshShading())
                {
                    command->drawMesh(drawCall.instanceMeshData.size(), 1, 1);
                }
                else
                {
                    command->bindIndexBuffer(vertexData->getIndexBuffer());
                    for (const auto& meshData : drawCall.instanceMeshData)
                    {
                        // all meshlets of a mesh share the same indices offset
                        command->drawIndexed(meshData.numIndices, 1, meshData.firstIndex, vertexData->getIndicesOffset(meshData.meshletOffset), 0);
                    }
                }
            }
            commands.add(std::move(command));
        }
    }

    graphics->executeCommands(std::move(commands));
    graphics->endRenderPass();
    // Sync color write with next pass/swapchain present
    //colorAttachment.getTexture()->pipelineBarrier(
    //    Gfx::SE_ACCESS_COLOR_ATTACHMENT_WRITE_BIT,
    //    Gfx::SE_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT,
    //    Gfx::SE_ACCESS_COLOR_ATTACHMENT_WRITE_BIT,
    //    Gfx::SE_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT
    //);
    // Sync depth with next pass/next frame
    //depthAttachment.getTexture()->pipelineBarrier(
    //    Gfx::SE_ACCESS_DEPTH_STENCIL_ATTACHMENT_READ_BIT | Gfx::SE_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BIT,
    //    Gfx::SE_PIPELINE_STAGE_LATE_FRAGMENT_TESTS_BIT,
    //    Gfx::SE_ACCESS_DEPTH_STENCIL_ATTACHMENT_READ_BIT,
    //    Gfx::SE_PIPELINE_STAGE_EARLY_FRAGMENT_TESTS_BIT
    //);
}

void BasePass::endFrame()
{
}

void BasePass::publishOutputs()
{
    colorAttachment = Gfx::RenderTargetAttachment(viewport,
        Gfx::SE_IMAGE_LAYOUT_UNDEFINED, Gfx::SE_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL,
        Gfx::SE_ATTACHMENT_LOAD_OP_CLEAR, Gfx::SE_ATTACHMENT_STORE_OP_STORE);
    resources->registerRenderPassOutput("BASEPASS_COLOR", colorAttachment);
}

void BasePass::createRenderPass()
{
    cullingBuffer = resources->requestBuffer("CULLINGBUFFER");

    depthAttachment = resources->requestRenderTarget("DEPTHPREPASS_DEPTH");
    depthAttachment.setLoadOp(Gfx::SE_ATTACHMENT_LOAD_OP_LOAD);
    depthAttachment.setInitialLayout(Gfx::SE_IMAGE_LAYOUT_GENERAL);
    depthAttachment.setFinalLayout(Gfx::SE_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL);
    Gfx::RenderTargetLayout layout = Gfx::RenderTargetLayout{
        .colorAttachments = { colorAttachment },
        .depthAttachment = depthAttachment,
    };
    Array<Gfx::SubPassDependency> dependency = {
        {
            .srcSubpass = ~0U,
            .dstSubpass = 0,
            .srcStage = Gfx::SE_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT | Gfx::SE_PIPELINE_STAGE_LATE_FRAGMENT_TESTS_BIT,
            .dstStage = Gfx::SE_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT | Gfx::SE_PIPELINE_STAGE_EARLY_FRAGMENT_TESTS_BIT,
            .srcAccess = Gfx::SE_ACCESS_COLOR_ATTACHMENT_WRITE_BIT | Gfx::SE_ACCESS_DEPTH_STENCIL_ATTACHMENT_READ_BIT | Gfx::SE_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BIT,
            .dstAccess = Gfx::SE_ACCESS_COLOR_ATTACHMENT_WRITE_BIT | Gfx::SE_ACCESS_DEPTH_STENCIL_ATTACHMENT_READ_BIT | Gfx::SE_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BIT,
        },
        {
            .srcSubpass = 0,
            .dstSubpass = ~0U,
            .srcStage = Gfx::SE_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT | Gfx::SE_PIPELINE_STAGE_LATE_FRAGMENT_TESTS_BIT,
            .dstStage = Gfx::SE_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT | Gfx::SE_PIPELINE_STAGE_EARLY_FRAGMENT_TESTS_BIT,
            .srcAccess = Gfx::SE_ACCESS_COLOR_ATTACHMENT_WRITE_BIT | Gfx::SE_ACCESS_DEPTH_STENCIL_ATTACHMENT_READ_BIT | Gfx::SE_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BIT,
            .dstAccess = Gfx::SE_ACCESS_COLOR_ATTACHMENT_WRITE_BIT | Gfx::SE_ACCESS_DEPTH_STENCIL_ATTACHMENT_READ_BIT | Gfx::SE_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BIT,
        },
    };
    renderPass = graphics->createRenderPass(std::move(layout), std::move(dependency), viewport);
    oLightIndexList = resources->requestBuffer("LIGHTCULLING_OLIGHTLIST");
    tLightIndexList = resources->requestBuffer("LIGHTCULLING_TLIGHTLIST");
    oLightGrid = resources->requestTexture("LIGHTCULLING_OLIGHTGRID");
    tLightGrid = resources->requestTexture("LIGHTCULLING_TLIGHTGRID");
}