#include "Rendering/Passes/BuiltinGaussianSplatPass.h"

#include "Components/GameObject.h"
#include "Debug/Logger.h"
#include "RHI/RHICommandList.h"
#include "RHI/RHIDevice.h"
#include "Rendering/Builtin/BuiltinPassLayoutUtils.h"
#include "Rendering/FrameData/RenderSceneData.h"
#include "Rendering/FrameData/VisibleGaussianSplatItem.h"
#include "Rendering/Internal/RenderSurfacePipelineUtils.h"
#include "Rendering/Internal/ShaderVariantUtils.h"
#include "Rendering/RenderSurface.h"
#include "Resources/BuiltinResources.h"
#include "Resources/GaussianSplat/GaussianSplat.h"
#include "Resources/Material/Material.h"
#include "Resources/Shader/Shader.h"

namespace XCEngine {
namespace Rendering {
namespace Passes {

namespace {

Resources::ShaderKeywordSet ResolvePassKeywordSet(
    const RenderSceneData& sceneData,
    const Resources::Material* material) {
    return Resources::CombineShaderKeywordSets(
        sceneData.globalShaderKeywords,
        material != nullptr ? material->GetKeywordSet() : Resources::ShaderKeywordSet());
}

const Resources::ShaderPass* FindCompatibleGaussianSplatPass(
    const Resources::Shader& shader,
    const RenderSceneData& sceneData,
    const Resources::Material* material,
    Resources::ShaderBackend backend) {
    const Resources::ShaderKeywordSet keywordSet = ResolvePassKeywordSet(sceneData, material);
    for (const Resources::ShaderPass& shaderPass : shader.GetPasses()) {
        if (ShaderPassMatchesBuiltinPass(shaderPass, BuiltinMaterialPass::GaussianSplat) &&
            ::XCEngine::Rendering::Internal::ShaderPassHasGraphicsVariants(
                shader,
                shaderPass.name,
                backend,
                keywordSet)) {
            return &shaderPass;
        }
    }

    return nullptr;
}

RHI::GraphicsPipelineDesc CreatePipelineDesc(
    RHI::RHIType backendType,
    RHI::RHIPipelineLayout* pipelineLayout,
    const Resources::Shader& shader,
    const Resources::ShaderPass& shaderPass,
    const Containers::String& passName,
    const Resources::ShaderKeywordSet& keywordSet,
    const Resources::Material* material,
    const RenderSurface& surface) {
    RHI::GraphicsPipelineDesc pipelineDesc = {};
    pipelineDesc.pipelineLayout = pipelineLayout;
    pipelineDesc.topologyType = static_cast<uint32_t>(RHI::PrimitiveTopologyType::Triangle);
    ::XCEngine::Rendering::Internal::ApplySingleColorAttachmentPropertiesToGraphicsPipelineDesc(surface, pipelineDesc);
    pipelineDesc.depthStencilFormat =
        static_cast<uint32_t>(::XCEngine::Rendering::Internal::ResolveSurfaceDepthFormat(surface));
    ApplyResolvedRenderState(&shaderPass, material, pipelineDesc);

    const Resources::ShaderBackend backend = ::XCEngine::Rendering::Internal::ToShaderBackend(backendType);
    if (const Resources::ShaderStageVariant* vertexVariant =
            shader.FindVariant(passName, Resources::ShaderType::Vertex, backend, keywordSet)) {
        ::XCEngine::Rendering::Internal::ApplyShaderStageVariant(
            shader.GetPath(),
            shaderPass,
            backend,
            *vertexVariant,
            pipelineDesc.vertexShader);
    }
    if (const Resources::ShaderStageVariant* fragmentVariant =
            shader.FindVariant(passName, Resources::ShaderType::Fragment, backend, keywordSet)) {
        ::XCEngine::Rendering::Internal::ApplyShaderStageVariant(
            shader.GetPath(),
            shaderPass,
            backend,
            *fragmentVariant,
            pipelineDesc.fragmentShader);
    }

    return pipelineDesc;
}

} // namespace

BuiltinGaussianSplatPass::~BuiltinGaussianSplatPass() {
    Shutdown();
}

const char* BuiltinGaussianSplatPass::GetName() const {
    return "BuiltinGaussianSplatPass";
}

bool BuiltinGaussianSplatPass::Initialize(const RenderContext& context) {
    return EnsureInitialized(context);
}

bool BuiltinGaussianSplatPass::PrepareGaussianSplatResources(
    const RenderContext& context,
    const RenderSceneData& sceneData) {
    if (!EnsureInitialized(context)) {
        return false;
    }

    for (const VisibleGaussianSplatItem& visibleGaussianSplat : sceneData.visibleGaussianSplats) {
        if (visibleGaussianSplat.gaussianSplat == nullptr ||
            !visibleGaussianSplat.gaussianSplat->IsValid()) {
            continue;
        }

        const RenderResourceCache::CachedGaussianSplat* cachedGaussianSplat =
            m_resourceCache.GetOrCreateGaussianSplat(m_device, visibleGaussianSplat.gaussianSplat);
        if (cachedGaussianSplat == nullptr ||
            cachedGaussianSplat->positions.shaderResourceView == nullptr ||
            cachedGaussianSplat->other.shaderResourceView == nullptr ||
            cachedGaussianSplat->color.shaderResourceView == nullptr) {
            return false;
        }
    }

    return true;
}

bool BuiltinGaussianSplatPass::Execute(const RenderPassContext& context) {
    if (!context.renderContext.IsValid()) {
        return false;
    }

    if (context.sceneData.visibleGaussianSplats.empty()) {
        return true;
    }

    const std::vector<RHI::RHIResourceView*>& colorAttachments = context.surface.GetColorAttachments();
    if (!::XCEngine::Rendering::Internal::HasSingleColorAttachment(context.surface) ||
        colorAttachments.empty() ||
        colorAttachments[0] == nullptr) {
        return false;
    }

    const Math::RectInt renderArea = context.surface.GetRenderArea();
    if (renderArea.width <= 0 || renderArea.height <= 0) {
        return false;
    }

    if (!PrepareGaussianSplatResources(context.renderContext, context.sceneData)) {
        return false;
    }

    RHI::RHICommandList* commandList = context.renderContext.commandList;
    RHI::RHIResourceView* renderTarget = colorAttachments[0];
    commandList->SetRenderTargets(1, &renderTarget, context.surface.GetDepthAttachment());

    const RHI::Viewport viewport = {
        static_cast<float>(renderArea.x),
        static_cast<float>(renderArea.y),
        static_cast<float>(renderArea.width),
        static_cast<float>(renderArea.height),
        0.0f,
        1.0f
    };
    const RHI::Rect scissorRect = {
        renderArea.x,
        renderArea.y,
        renderArea.x + renderArea.width,
        renderArea.y + renderArea.height
    };
    commandList->SetViewport(viewport);
    commandList->SetScissorRect(scissorRect);
    commandList->SetPrimitiveTopology(RHI::PrimitiveTopology::TriangleList);

    for (const VisibleGaussianSplatItem& visibleGaussianSplat : context.sceneData.visibleGaussianSplats) {
        if (!DrawVisibleGaussianSplat(
                context.renderContext,
                context.surface,
                context.sceneData,
                visibleGaussianSplat)) {
            return false;
        }
    }

    return true;
}

void BuiltinGaussianSplatPass::Shutdown() {
    DestroyResources();
}

bool BuiltinGaussianSplatPass::EnsureInitialized(const RenderContext& context) {
    if (!context.IsValid()) {
        return false;
    }

    if (m_device == context.device &&
        m_backendType == context.backendType &&
        m_builtinGaussianSplatShader.IsValid() &&
        m_builtinGaussianSplatMaterial != nullptr) {
        return true;
    }

    DestroyResources();
    return CreateResources(context);
}

bool BuiltinGaussianSplatPass::CreateResources(const RenderContext& context) {
    m_device = context.device;
    m_backendType = context.backendType;
    m_builtinGaussianSplatShader = Resources::ResourceManager::Get().Load<Resources::Shader>(
        Resources::GetBuiltinGaussianSplatShaderPath());
    if (!m_builtinGaussianSplatShader.IsValid()) {
        Debug::Logger::Get().Error(
            Debug::LogCategory::Rendering,
            "BuiltinGaussianSplatPass failed to load builtin gaussian splat shader resource");
        DestroyResources();
        return false;
    }

    m_builtinGaussianSplatMaterial = std::make_unique<Resources::Material>();
    Resources::IResource::ConstructParams params = {};
    params.name = "BuiltinGaussianSplatMaterial";
    params.path = "builtin://materials/gaussian-splat-default";
    params.guid = Resources::ResourceGUID::Generate(params.path);
    m_builtinGaussianSplatMaterial->Initialize(params);
    m_builtinGaussianSplatMaterial->SetShader(m_builtinGaussianSplatShader);
    m_builtinGaussianSplatMaterial->SetRenderQueue(Resources::MaterialRenderQueue::Transparent);
    return true;
}

void BuiltinGaussianSplatPass::DestroyResources() {
    m_resourceCache.Shutdown();

    for (auto& pipelinePair : m_pipelineStates) {
        if (pipelinePair.second != nullptr) {
            pipelinePair.second->Shutdown();
            delete pipelinePair.second;
        }
    }
    m_pipelineStates.clear();

    for (auto& descriptorSetPair : m_dynamicDescriptorSets) {
        DestroyOwnedDescriptorSet(descriptorSetPair.second.descriptorSet);
    }
    m_dynamicDescriptorSets.clear();

    for (auto& passLayoutPair : m_passResourceLayouts) {
        DestroyPassResourceLayout(passLayoutPair.second);
    }
    m_passResourceLayouts.clear();

    m_builtinGaussianSplatMaterial.reset();
    m_builtinGaussianSplatShader.Reset();
    m_device = nullptr;
    m_backendType = RHI::RHIType::D3D12;
}

const Resources::Material* BuiltinGaussianSplatPass::ResolveGaussianSplatMaterial(
    const VisibleGaussianSplatItem& visibleGaussianSplat) const {
    if (visibleGaussianSplat.material != nullptr &&
        visibleGaussianSplat.material->GetShader() != nullptr &&
        MatchesBuiltinPass(visibleGaussianSplat.material, BuiltinMaterialPass::GaussianSplat)) {
        return visibleGaussianSplat.material;
    }

    return m_builtinGaussianSplatMaterial.get();
}

BuiltinGaussianSplatPass::ResolvedShaderPass BuiltinGaussianSplatPass::ResolveGaussianSplatShaderPass(
    const RenderSceneData& sceneData,
    const Resources::Material* material) const {
    ResolvedShaderPass resolved = {};
    const Resources::ShaderBackend backend = ::XCEngine::Rendering::Internal::ToShaderBackend(m_backendType);

    if (material != nullptr && material->GetShader() != nullptr) {
        const Resources::Shader* shader = material->GetShader();
        if (const Resources::ShaderPass* shaderPass =
                FindCompatibleGaussianSplatPass(*shader, sceneData, material, backend)) {
            resolved.shader = shader;
            resolved.pass = shaderPass;
            resolved.passName = shaderPass->name;
            return resolved;
        }
    }

    if (m_builtinGaussianSplatShader.IsValid()) {
        const Resources::Shader* shader = m_builtinGaussianSplatShader.Get();
        if (const Resources::ShaderPass* shaderPass =
                FindCompatibleGaussianSplatPass(*shader, sceneData, material, backend)) {
            resolved.shader = shader;
            resolved.pass = shaderPass;
            resolved.passName = shaderPass->name;
        }
    }

    return resolved;
}

BuiltinGaussianSplatPass::PassResourceLayout* BuiltinGaussianSplatPass::GetOrCreatePassResourceLayout(
    const RenderContext& context,
    const ResolvedShaderPass& resolvedShaderPass) {
    if (resolvedShaderPass.shader == nullptr || resolvedShaderPass.pass == nullptr) {
        return nullptr;
    }

    PassLayoutKey passLayoutKey = {};
    passLayoutKey.shader = resolvedShaderPass.shader;
    passLayoutKey.passName = resolvedShaderPass.passName;

    const auto existing = m_passResourceLayouts.find(passLayoutKey);
    if (existing != m_passResourceLayouts.end()) {
        return &existing->second;
    }

    PassResourceLayout passLayout = {};
    auto failLayout = [this, &passLayout](const char* message) -> PassResourceLayout* {
        Debug::Logger::Get().Error(Debug::LogCategory::Rendering, message);
        DestroyPassResourceLayout(passLayout);
        return nullptr;
    };

    BuiltinPassResourceBindingPlan bindingPlan = {};
    Containers::String bindingPlanError;
    if (!TryBuildBuiltinPassResourceBindingPlan(*resolvedShaderPass.pass, bindingPlan, &bindingPlanError)) {
        const Containers::String contextualError =
            Containers::String("BuiltinGaussianSplatPass failed to resolve pass resource bindings for shader='") +
            resolvedShaderPass.shader->GetPath() +
            "', pass='" + resolvedShaderPass.passName +
            "': " + bindingPlanError +
            ". Bindings: " + DescribeShaderResourceBindings(resolvedShaderPass.pass->resources);
        return failLayout(contextualError.CStr());
    }

    Containers::String setLayoutError;
    if (!TryBuildBuiltinPassSetLayouts(bindingPlan, passLayout.setLayouts, &setLayoutError)) {
        return failLayout(setLayoutError.CStr());
    }

    passLayout.firstDescriptorSet = bindingPlan.firstDescriptorSet;
    passLayout.descriptorSetCount = bindingPlan.descriptorSetCount;
    passLayout.perObject = bindingPlan.perObject;
    passLayout.material = bindingPlan.material;
    passLayout.gaussianSplatPositionBuffer = bindingPlan.gaussianSplatPositionBuffer;
    passLayout.gaussianSplatOtherBuffer = bindingPlan.gaussianSplatOtherBuffer;
    passLayout.gaussianSplatColorBuffer = bindingPlan.gaussianSplatColorBuffer;
    passLayout.gaussianSplatSHBuffer = bindingPlan.gaussianSplatSHBuffer;

    if (!passLayout.perObject.IsValid()) {
        return failLayout("BuiltinGaussianSplatPass requires a PerObject resource binding");
    }
    if (!passLayout.material.IsValid()) {
        return failLayout("BuiltinGaussianSplatPass requires a Material resource binding");
    }
    if (!passLayout.gaussianSplatPositionBuffer.IsValid() ||
        !passLayout.gaussianSplatOtherBuffer.IsValid() ||
        !passLayout.gaussianSplatColorBuffer.IsValid()) {
        return failLayout("BuiltinGaussianSplatPass requires position, other, and color gaussian splat buffer bindings");
    }

    std::vector<RHI::DescriptorSetLayoutDesc> nativeSetLayouts(passLayout.setLayouts.size());
    for (size_t setIndex = 0; setIndex < passLayout.setLayouts.size(); ++setIndex) {
        nativeSetLayouts[setIndex] = passLayout.setLayouts[setIndex].layout;
    }

    RHI::RHIPipelineLayoutDesc pipelineLayoutDesc = {};
    pipelineLayoutDesc.setLayouts = nativeSetLayouts.empty() ? nullptr : nativeSetLayouts.data();
    pipelineLayoutDesc.setLayoutCount = static_cast<Core::uint32>(nativeSetLayouts.size());
    passLayout.pipelineLayout = context.device->CreatePipelineLayout(pipelineLayoutDesc);
    if (passLayout.pipelineLayout == nullptr) {
        return failLayout("BuiltinGaussianSplatPass failed to create pipeline layout from shader pass resources");
    }

    const auto result = m_passResourceLayouts.emplace(passLayoutKey, passLayout);
    PassResourceLayout& storedPassLayout = result.first->second;
    RefreshBuiltinPassSetLayouts(storedPassLayout.setLayouts);
    return &storedPassLayout;
}

RHI::RHIPipelineState* BuiltinGaussianSplatPass::GetOrCreatePipelineState(
    const RenderContext& context,
    const RenderSurface& surface,
    const RenderSceneData& sceneData,
    const Resources::Material* material) {
    const Resources::ShaderKeywordSet keywordSet = ResolvePassKeywordSet(sceneData, material);
    const ResolvedShaderPass resolvedShaderPass = ResolveGaussianSplatShaderPass(sceneData, material);
    if (resolvedShaderPass.shader == nullptr || resolvedShaderPass.pass == nullptr) {
        return nullptr;
    }

    PassResourceLayout* passLayout = GetOrCreatePassResourceLayout(context, resolvedShaderPass);
    if (passLayout == nullptr || passLayout->pipelineLayout == nullptr) {
        return nullptr;
    }

    PipelineStateKey pipelineKey = {};
    pipelineKey.renderState =
        BuildStaticPipelineRenderStateKey(ResolveEffectiveRenderState(resolvedShaderPass.pass, material));
    pipelineKey.shader = resolvedShaderPass.shader;
    pipelineKey.passName = resolvedShaderPass.passName;
    pipelineKey.keywordSignature = ::XCEngine::Rendering::Internal::BuildShaderKeywordSignature(keywordSet);
    pipelineKey.renderTargetCount =
        ::XCEngine::Rendering::Internal::HasSingleColorAttachment(surface) ? 1u : 0u;
    pipelineKey.renderTargetFormat =
        static_cast<Core::uint32>(::XCEngine::Rendering::Internal::ResolveSurfaceColorFormat(surface, 0u));
    pipelineKey.depthStencilFormat =
        static_cast<Core::uint32>(::XCEngine::Rendering::Internal::ResolveSurfaceDepthFormat(surface));
    pipelineKey.sampleCount = ::XCEngine::Rendering::Internal::ResolveSurfaceSampleCount(surface);
    pipelineKey.sampleQuality = ::XCEngine::Rendering::Internal::ResolveSurfaceSampleQuality(surface);

    const auto existing = m_pipelineStates.find(pipelineKey);
    if (existing != m_pipelineStates.end()) {
        return existing->second;
    }

    const RHI::GraphicsPipelineDesc pipelineDesc =
        CreatePipelineDesc(
            context.backendType,
            passLayout->pipelineLayout,
            *resolvedShaderPass.shader,
            *resolvedShaderPass.pass,
            resolvedShaderPass.passName,
            keywordSet,
            material,
            surface);
    RHI::RHIPipelineState* pipelineState = context.device->CreatePipelineState(pipelineDesc);
    if (pipelineState == nullptr || !pipelineState->IsValid()) {
        if (pipelineState != nullptr) {
            pipelineState->Shutdown();
            delete pipelineState;
        }
        return nullptr;
    }

    m_pipelineStates.emplace(pipelineKey, pipelineState);
    return pipelineState;
}

bool BuiltinGaussianSplatPass::CreateOwnedDescriptorSet(
    const BuiltinPassSetLayoutMetadata& setLayout,
    OwnedDescriptorSet& descriptorSet) {
    RHI::DescriptorPoolDesc poolDesc = {};
    poolDesc.type = setLayout.heapType;
    poolDesc.descriptorCount = CountBuiltinPassHeapDescriptors(setLayout.heapType, setLayout.bindings);
    poolDesc.shaderVisible = setLayout.shaderVisible;

    descriptorSet.pool = m_device->CreateDescriptorPool(poolDesc);
    if (descriptorSet.pool == nullptr) {
        return false;
    }

    descriptorSet.set = descriptorSet.pool->AllocateSet(setLayout.layout);
    if (descriptorSet.set == nullptr) {
        DestroyOwnedDescriptorSet(descriptorSet);
        return false;
    }

    return true;
}

BuiltinGaussianSplatPass::CachedDescriptorSet* BuiltinGaussianSplatPass::GetOrCreateDynamicDescriptorSet(
    const PassLayoutKey& passLayoutKey,
    const PassResourceLayout& passLayout,
    const BuiltinPassSetLayoutMetadata& setLayout,
    Core::uint32 setIndex,
    Core::uint64 objectId,
    const Resources::Material* material,
    const Resources::GaussianSplat* gaussianSplat,
    const MaterialConstantPayloadView& materialConstants,
    const RenderResourceCache::CachedGaussianSplat& cachedGaussianSplat) {
    DynamicDescriptorSetKey key = {};
    key.passLayout = passLayoutKey;
    key.setIndex = setIndex;
    key.objectId = objectId;
    key.material = material;
    key.gaussianSplat = gaussianSplat;

    CachedDescriptorSet& cachedDescriptorSet = m_dynamicDescriptorSets[key];
    if (cachedDescriptorSet.descriptorSet.set == nullptr) {
        if (!CreateOwnedDescriptorSet(setLayout, cachedDescriptorSet.descriptorSet)) {
            return nullptr;
        }
    }

    const Core::uint64 materialVersion = material != nullptr ? material->GetChangeVersion() : 0u;
    if (setLayout.usesMaterial) {
        if (!passLayout.material.IsValid() ||
            passLayout.material.set != setIndex ||
            !materialConstants.IsValid()) {
            return nullptr;
        }

        if (cachedDescriptorSet.materialVersion != materialVersion) {
            cachedDescriptorSet.descriptorSet.set->WriteConstant(
                passLayout.material.binding,
                materialConstants.data,
                materialConstants.size);
        }
    }

    if (setLayout.usesGaussianSplatPositionBuffer) {
        if (cachedGaussianSplat.positions.shaderResourceView == nullptr ||
            !passLayout.gaussianSplatPositionBuffer.IsValid() ||
            passLayout.gaussianSplatPositionBuffer.set != setIndex) {
            return nullptr;
        }

        if (cachedDescriptorSet.positionsView != cachedGaussianSplat.positions.shaderResourceView) {
            cachedDescriptorSet.descriptorSet.set->Update(
                passLayout.gaussianSplatPositionBuffer.binding,
                cachedGaussianSplat.positions.shaderResourceView);
        }
    }

    if (setLayout.usesGaussianSplatOtherBuffer) {
        if (cachedGaussianSplat.other.shaderResourceView == nullptr ||
            !passLayout.gaussianSplatOtherBuffer.IsValid() ||
            passLayout.gaussianSplatOtherBuffer.set != setIndex) {
            return nullptr;
        }

        if (cachedDescriptorSet.otherView != cachedGaussianSplat.other.shaderResourceView) {
            cachedDescriptorSet.descriptorSet.set->Update(
                passLayout.gaussianSplatOtherBuffer.binding,
                cachedGaussianSplat.other.shaderResourceView);
        }
    }

    if (setLayout.usesGaussianSplatColorBuffer) {
        if (cachedGaussianSplat.color.shaderResourceView == nullptr ||
            !passLayout.gaussianSplatColorBuffer.IsValid() ||
            passLayout.gaussianSplatColorBuffer.set != setIndex) {
            return nullptr;
        }

        if (cachedDescriptorSet.colorView != cachedGaussianSplat.color.shaderResourceView) {
            cachedDescriptorSet.descriptorSet.set->Update(
                passLayout.gaussianSplatColorBuffer.binding,
                cachedGaussianSplat.color.shaderResourceView);
        }
    }

    if (setLayout.usesGaussianSplatSHBuffer) {
        if (cachedGaussianSplat.sh.shaderResourceView == nullptr ||
            !passLayout.gaussianSplatSHBuffer.IsValid() ||
            passLayout.gaussianSplatSHBuffer.set != setIndex) {
            return nullptr;
        }

        if (cachedDescriptorSet.shView != cachedGaussianSplat.sh.shaderResourceView) {
            cachedDescriptorSet.descriptorSet.set->Update(
                passLayout.gaussianSplatSHBuffer.binding,
                cachedGaussianSplat.sh.shaderResourceView);
        }
    }

    cachedDescriptorSet.materialVersion = materialVersion;
    cachedDescriptorSet.positionsView = cachedGaussianSplat.positions.shaderResourceView;
    cachedDescriptorSet.otherView = cachedGaussianSplat.other.shaderResourceView;
    cachedDescriptorSet.colorView = cachedGaussianSplat.color.shaderResourceView;
    cachedDescriptorSet.shView = cachedGaussianSplat.sh.shaderResourceView;
    return &cachedDescriptorSet;
}

void BuiltinGaussianSplatPass::DestroyOwnedDescriptorSet(OwnedDescriptorSet& descriptorSet) {
    if (descriptorSet.set != nullptr) {
        descriptorSet.set->Shutdown();
        delete descriptorSet.set;
        descriptorSet.set = nullptr;
    }

    if (descriptorSet.pool != nullptr) {
        descriptorSet.pool->Shutdown();
        delete descriptorSet.pool;
        descriptorSet.pool = nullptr;
    }
}

void BuiltinGaussianSplatPass::DestroyPassResourceLayout(PassResourceLayout& passLayout) {
    if (passLayout.pipelineLayout != nullptr) {
        passLayout.pipelineLayout->Shutdown();
        delete passLayout.pipelineLayout;
        passLayout.pipelineLayout = nullptr;
    }

    passLayout.setLayouts.clear();
    passLayout.firstDescriptorSet = 0;
    passLayout.descriptorSetCount = 0;
    passLayout.perObject = {};
    passLayout.material = {};
    passLayout.gaussianSplatPositionBuffer = {};
    passLayout.gaussianSplatOtherBuffer = {};
    passLayout.gaussianSplatColorBuffer = {};
    passLayout.gaussianSplatSHBuffer = {};
}

bool BuiltinGaussianSplatPass::DrawVisibleGaussianSplat(
    const RenderContext& context,
    const RenderSurface& surface,
    const RenderSceneData& sceneData,
    const VisibleGaussianSplatItem& visibleGaussianSplat) {
    if (visibleGaussianSplat.gameObject == nullptr ||
        visibleGaussianSplat.gaussianSplat == nullptr ||
        !visibleGaussianSplat.gaussianSplat->IsValid()) {
        return false;
    }

    const RenderResourceCache::CachedGaussianSplat* cachedGaussianSplat =
        m_resourceCache.GetOrCreateGaussianSplat(m_device, visibleGaussianSplat.gaussianSplat);
    if (cachedGaussianSplat == nullptr ||
        cachedGaussianSplat->positions.shaderResourceView == nullptr ||
        cachedGaussianSplat->other.shaderResourceView == nullptr ||
        cachedGaussianSplat->color.shaderResourceView == nullptr) {
        return false;
    }

    const Resources::Material* material = ResolveGaussianSplatMaterial(visibleGaussianSplat);
    if (material == nullptr) {
        return false;
    }

    const ResolvedShaderPass resolvedShaderPass = ResolveGaussianSplatShaderPass(sceneData, material);
    if (resolvedShaderPass.shader == nullptr || resolvedShaderPass.pass == nullptr) {
        return false;
    }

    PassLayoutKey passLayoutKey = {};
    passLayoutKey.shader = resolvedShaderPass.shader;
    passLayoutKey.passName = resolvedShaderPass.passName;

    PassResourceLayout* passLayout = GetOrCreatePassResourceLayout(context, resolvedShaderPass);
    RHI::RHIPipelineState* pipelineState = GetOrCreatePipelineState(context, surface, sceneData, material);
    if (passLayout == nullptr || pipelineState == nullptr) {
        return false;
    }

    const MaterialConstantPayloadView materialConstants = ResolveSchemaMaterialConstantPayload(material);
    if (!materialConstants.IsValid()) {
        return false;
    }

    RHI::RHICommandList* commandList = context.commandList;
    commandList->SetPipelineState(pipelineState);

    const PerObjectConstants perObjectConstants = {
        sceneData.cameraData.projection,
        sceneData.cameraData.view,
        visibleGaussianSplat.localToWorld.Transpose(),
        Math::Vector4(sceneData.cameraData.worldRight, 0.0f),
        Math::Vector4(sceneData.cameraData.worldUp, 0.0f)
    };

    if (passLayout->descriptorSetCount > 0u) {
        std::vector<RHI::RHIDescriptorSet*> descriptorSets(passLayout->descriptorSetCount, nullptr);
        for (Core::uint32 descriptorOffset = 0u; descriptorOffset < passLayout->descriptorSetCount; ++descriptorOffset) {
            const Core::uint32 setIndex = passLayout->firstDescriptorSet + descriptorOffset;
            if (setIndex >= passLayout->setLayouts.size()) {
                return false;
            }

            const BuiltinPassSetLayoutMetadata& setLayout = passLayout->setLayouts[setIndex];
            if (!(setLayout.usesPerObject ||
                  setLayout.usesMaterial ||
                  setLayout.usesGaussianSplatPositionBuffer ||
                  setLayout.usesGaussianSplatOtherBuffer ||
                  setLayout.usesGaussianSplatColorBuffer ||
                  setLayout.usesGaussianSplatSHBuffer)) {
                return false;
            }

            const Core::uint64 objectId =
                setLayout.usesPerObject ? visibleGaussianSplat.gameObject->GetID() : 0u;
            const Resources::Material* materialKey =
                setLayout.usesMaterial ? material : nullptr;
            const Resources::GaussianSplat* gaussianSplatKey =
                (setLayout.usesGaussianSplatPositionBuffer ||
                 setLayout.usesGaussianSplatOtherBuffer ||
                 setLayout.usesGaussianSplatColorBuffer ||
                 setLayout.usesGaussianSplatSHBuffer)
                    ? visibleGaussianSplat.gaussianSplat
                    : nullptr;

            CachedDescriptorSet* cachedDescriptorSet = GetOrCreateDynamicDescriptorSet(
                passLayoutKey,
                *passLayout,
                setLayout,
                setIndex,
                objectId,
                materialKey,
                gaussianSplatKey,
                materialConstants,
                *cachedGaussianSplat);
            if (cachedDescriptorSet == nullptr || cachedDescriptorSet->descriptorSet.set == nullptr) {
                return false;
            }

            RHI::RHIDescriptorSet* descriptorSet = cachedDescriptorSet->descriptorSet.set;
            if (setLayout.usesPerObject) {
                if (!passLayout->perObject.IsValid() || passLayout->perObject.set != setIndex) {
                    return false;
                }

                descriptorSet->WriteConstant(
                    passLayout->perObject.binding,
                    &perObjectConstants,
                    sizeof(perObjectConstants));
            }

            descriptorSets[descriptorOffset] = descriptorSet;
        }

        commandList->SetGraphicsDescriptorSets(
            passLayout->firstDescriptorSet,
            passLayout->descriptorSetCount,
            descriptorSets.data(),
            passLayout->pipelineLayout);
    }

    ApplyDynamicRenderState(ResolveEffectiveRenderState(resolvedShaderPass.pass, material), *commandList);
    commandList->Draw(6u, cachedGaussianSplat->splatCount, 0u, 0u);
    return true;
}

} // namespace Passes
} // namespace Rendering
} // namespace XCEngine