MetaCore/Source/MetaCoreRender/Private/MetaCoreRuntimeUiRenderer.cpp

#include "MetaCoreRender/MetaCoreRuntimeUiRenderer.h"

#include <RmlUi/Core.h>

#include <algorithm>
#include <cmath>
#include <chrono>
#include <cstring>
#include <cstdint>
#include <memory>
#include <string>
#include <unordered_map>
#include <utility>

namespace MetaCore {

namespace {

[[nodiscard]] float MetaCoreRuntimeUiEdge(
    const MetaCoreRuntimeUiDrawVertex& a,
    const MetaCoreRuntimeUiDrawVertex& b,
    float x,
    float y
) {
    return (x - a.X) * (b.Y - a.Y) - (y - a.Y) * (b.X - a.X);
}

[[nodiscard]] std::uint8_t MetaCoreRuntimeUiByte(float value) {
    return static_cast<std::uint8_t>(std::clamp(value, 0.0F, 255.0F));
}

[[nodiscard]] std::string MetaCoreEscapeRuntimeUiRmlText(std::string_view value) {
    std::string escaped;
    escaped.reserve(value.size());
    for (char c : value) {
        switch (c) {
            case '&': escaped += "&amp;"; break;
            case '<': escaped += "&lt;"; break;
            case '>': escaped += "&gt;"; break;
            case '"': escaped += "&quot;"; break;
            case '\'': escaped += "&apos;"; break;
            default: escaped.push_back(c); break;
        }
    }
    return escaped;
}

void MetaCoreRuntimeUiBlendPixel(
    MetaCoreRuntimeUiRasterFrame& rasterFrame,
    std::int32_t x,
    std::int32_t y,
    float red,
    float green,
    float blue,
    float alpha
) {
    if (x < 0 || y < 0 || x >= rasterFrame.Width || y >= rasterFrame.Height) {
        return;
    }

    const std::size_t pixelOffset =
        (static_cast<std::size_t>(y) * static_cast<std::size_t>(rasterFrame.Width) + static_cast<std::size_t>(x)) * 4U;
    if (pixelOffset + 3U >= rasterFrame.Rgba.size()) {
        return;
    }

    const float sourceAlpha = std::clamp(alpha / 255.0F, 0.0F, 1.0F);
    const float inverseAlpha = 1.0F - sourceAlpha;
    rasterFrame.Rgba[pixelOffset + 0U] = MetaCoreRuntimeUiByte(red + static_cast<float>(rasterFrame.Rgba[pixelOffset + 0U]) * inverseAlpha);
    rasterFrame.Rgba[pixelOffset + 1U] = MetaCoreRuntimeUiByte(green + static_cast<float>(rasterFrame.Rgba[pixelOffset + 1U]) * inverseAlpha);
    rasterFrame.Rgba[pixelOffset + 2U] = MetaCoreRuntimeUiByte(blue + static_cast<float>(rasterFrame.Rgba[pixelOffset + 2U]) * inverseAlpha);
    rasterFrame.Rgba[pixelOffset + 3U] = MetaCoreRuntimeUiByte(alpha + static_cast<float>(rasterFrame.Rgba[pixelOffset + 3U]) * inverseAlpha);
}

void MetaCoreRuntimeUiRasterizeTriangle(
    MetaCoreRuntimeUiRasterFrame& rasterFrame,
    const MetaCoreRuntimeUiDrawCommand& command,
    const MetaCoreRuntimeUiDrawVertex& v0,
    const MetaCoreRuntimeUiDrawVertex& v1,
    const MetaCoreRuntimeUiDrawVertex& v2
) {
    const float area = MetaCoreRuntimeUiEdge(v0, v1, v2.X, v2.Y);
    if (std::abs(area) <= 0.0001F) {
        return;
    }

    std::int32_t minX = static_cast<std::int32_t>(std::floor(std::min({v0.X, v1.X, v2.X})));
    std::int32_t minY = static_cast<std::int32_t>(std::floor(std::min({v0.Y, v1.Y, v2.Y})));
    std::int32_t maxX = static_cast<std::int32_t>(std::ceil(std::max({v0.X, v1.X, v2.X})));
    std::int32_t maxY = static_cast<std::int32_t>(std::ceil(std::max({v0.Y, v1.Y, v2.Y})));

    minX = std::clamp(minX, 0, std::max(0, rasterFrame.Width - 1));
    minY = std::clamp(minY, 0, std::max(0, rasterFrame.Height - 1));
    maxX = std::clamp(maxX, 0, std::max(0, rasterFrame.Width - 1));
    maxY = std::clamp(maxY, 0, std::max(0, rasterFrame.Height - 1));

    if (command.ScissorEnabled) {
        minX = std::max(minX, command.ScissorLeft);
        minY = std::max(minY, command.ScissorTop);
        maxX = std::min(maxX, command.ScissorRight);
        maxY = std::min(maxY, command.ScissorBottom);
    }

    if (minX > maxX || minY > maxY) {
        return;
    }

    const bool positiveArea = area > 0.0F;
    for (std::int32_t y = minY; y <= maxY; ++y) {
        for (std::int32_t x = minX; x <= maxX; ++x) {
            const float sampleX = static_cast<float>(x) + 0.5F;
            const float sampleY = static_cast<float>(y) + 0.5F;
            const float w0 = MetaCoreRuntimeUiEdge(v1, v2, sampleX, sampleY);
            const float w1 = MetaCoreRuntimeUiEdge(v2, v0, sampleX, sampleY);
            const float w2 = MetaCoreRuntimeUiEdge(v0, v1, sampleX, sampleY);

            const bool inside = positiveArea
                ? (w0 >= 0.0F && w1 >= 0.0F && w2 >= 0.0F)
                : (w0 <= 0.0F && w1 <= 0.0F && w2 <= 0.0F);
            if (!inside) {
                continue;
            }

            const float invArea = 1.0F / area;
            const float b0 = w0 * invArea;
            const float b1 = w1 * invArea;
            const float b2 = w2 * invArea;
            MetaCoreRuntimeUiBlendPixel(
                rasterFrame,
                x,
                y,
                b0 * static_cast<float>(v0.R) + b1 * static_cast<float>(v1.R) + b2 * static_cast<float>(v2.R),
                b0 * static_cast<float>(v0.G) + b1 * static_cast<float>(v1.G) + b2 * static_cast<float>(v2.G),
                b0 * static_cast<float>(v0.B) + b1 * static_cast<float>(v1.B) + b2 * static_cast<float>(v2.B),
                b0 * static_cast<float>(v0.A) + b1 * static_cast<float>(v1.A) + b2 * static_cast<float>(v2.A)
            );
        }
    }
}

void MetaCoreRuntimeUiRasterizeFrame(
    const MetaCoreRuntimeUiFrame& frame,
    MetaCoreRuntimeUiRasterFrame& rasterFrame,
    MetaCoreRuntimeUiRenderStats& stats,
    std::int32_t width,
    std::int32_t height
) {
    rasterFrame.Width = std::max<std::int32_t>(0, width);
    rasterFrame.Height = std::max<std::int32_t>(0, height);
    const std::size_t pixelCount =
        static_cast<std::size_t>(rasterFrame.Width) * static_cast<std::size_t>(rasterFrame.Height);
    rasterFrame.Rgba.assign(pixelCount * 4U, 0);

    for (const MetaCoreRuntimeUiDrawCommand& command : frame.Commands) {
        const std::size_t triangleCount = command.IndexCount / 3U;
        for (std::size_t triangleIndex = 0; triangleIndex < triangleCount; ++triangleIndex) {
            const std::size_t i0 = command.IndexOffset + triangleIndex * 3U + 0U;
            const std::size_t i1 = command.IndexOffset + triangleIndex * 3U + 1U;
            const std::size_t i2 = command.IndexOffset + triangleIndex * 3U + 2U;
            if (i2 >= frame.Indices.size()) {
                continue;
            }

            const std::uint32_t v0Index = frame.Indices[i0];
            const std::uint32_t v1Index = frame.Indices[i1];
            const std::uint32_t v2Index = frame.Indices[i2];
            if (v0Index >= frame.Vertices.size() ||
                v1Index >= frame.Vertices.size() ||
                v2Index >= frame.Vertices.size()) {
                continue;
            }

            MetaCoreRuntimeUiRasterizeTriangle(
                rasterFrame,
                command,
                frame.Vertices[v0Index],
                frame.Vertices[v1Index],
                frame.Vertices[v2Index]
            );
        }
    }

    std::size_t touchedPixelCount = 0;
    for (std::size_t pixelIndex = 0; pixelIndex < pixelCount; ++pixelIndex) {
        if (rasterFrame.Rgba[pixelIndex * 4U + 3U] > 0) {
            ++touchedPixelCount;
        }
    }
    stats.RasterPixelCount = pixelCount;
    stats.RasterTouchedPixelCount = touchedPixelCount;
}

class MetaCoreRmlSystemInterface final : public Rml::SystemInterface {
public:
    double GetElapsedTime() override {
        return ElapsedSeconds_;
    }

    void Advance(double deltaSeconds) {
        ElapsedSeconds_ += std::max(0.0, deltaSeconds);
    }

    bool LogMessage(Rml::Log::Type type, const Rml::String& message) override {
        LastLogType_ = type;
        LastMessage_ = message;
        return true;
    }

    [[nodiscard]] const std::string& GetLastMessage() const {
        return LastMessage_;
    }

private:
    double ElapsedSeconds_ = 0.0;
    Rml::Log::Type LastLogType_ = Rml::Log::LT_INFO;
    std::string LastMessage_{};
};

struct MetaCoreRmlMemoryFile {
    std::string Data{};
    std::size_t Cursor = 0;
};

[[nodiscard]] std::string MetaCoreNormalizeRmlPath(std::string path) {
    std::replace(path.begin(), path.end(), '\\', '/');
    while (path.find("//") != std::string::npos) {
        path.erase(path.find("//"), 1);
    }
    return path;
}

[[nodiscard]] std::string MetaCoreRmlBasename(const std::string& path) {
    const std::string normalized = MetaCoreNormalizeRmlPath(path);
    const auto slash = normalized.find_last_of('/');
    return slash == std::string::npos ? normalized : normalized.substr(slash + 1);
}

class MetaCoreRmlMemoryFileInterface final : public Rml::FileInterface {
public:
    void SetVirtualFile(std::string path, std::string data) {
        if (path.empty()) {
            path = "MetaCoreRuntimeUi.rcss";
        }

        const std::string normalized = MetaCoreNormalizeRmlPath(std::move(path));
        VirtualFiles_[normalized] = data;
        VirtualFiles_[MetaCoreRmlBasename(normalized)] = std::move(data);
    }

    void Clear() {
        VirtualFiles_.clear();
        OpenFiles_.clear();
    }

    Rml::FileHandle Open(const Rml::String& path) override {
        const std::string normalized = MetaCoreNormalizeRmlPath(path);
        auto iterator = VirtualFiles_.find(normalized);
        if (iterator == VirtualFiles_.end()) {
            iterator = VirtualFiles_.find(MetaCoreRmlBasename(normalized));
        }
        if (iterator == VirtualFiles_.end()) {
            return 0;
        }

        const Rml::FileHandle handle = NextHandle_++;
        OpenFiles_.emplace(handle, MetaCoreRmlMemoryFile{iterator->second, 0});
        return handle;
    }

    void Close(Rml::FileHandle file) override {
        OpenFiles_.erase(file);
    }

    size_t Read(void* buffer, size_t size, Rml::FileHandle file) override {
        auto iterator = OpenFiles_.find(file);
        if (iterator == OpenFiles_.end() || buffer == nullptr || size == 0) {
            return 0;
        }

        MetaCoreRmlMemoryFile& memoryFile = iterator->second;
        const std::size_t remaining = memoryFile.Cursor < memoryFile.Data.size()
            ? memoryFile.Data.size() - memoryFile.Cursor
            : 0;
        const std::size_t bytesToRead = std::min(size, remaining);
        if (bytesToRead > 0) {
            std::memcpy(buffer, memoryFile.Data.data() + memoryFile.Cursor, bytesToRead);
            memoryFile.Cursor += bytesToRead;
        }
        return bytesToRead;
    }

    bool Seek(Rml::FileHandle file, long offset, int origin) override {
        auto iterator = OpenFiles_.find(file);
        if (iterator == OpenFiles_.end()) {
            return false;
        }

        MetaCoreRmlMemoryFile& memoryFile = iterator->second;
        long base = 0;
        if (origin == SEEK_CUR) {
            base = static_cast<long>(memoryFile.Cursor);
        } else if (origin == SEEK_END) {
            base = static_cast<long>(memoryFile.Data.size());
        }

        const long next = base + offset;
        if (next < 0) {
            return false;
        }

        memoryFile.Cursor = std::min<std::size_t>(
            static_cast<std::size_t>(next),
            memoryFile.Data.size()
        );
        return true;
    }

    size_t Tell(Rml::FileHandle file) override {
        auto iterator = OpenFiles_.find(file);
        return iterator == OpenFiles_.end() ? 0 : iterator->second.Cursor;
    }

private:
    Rml::FileHandle NextHandle_ = 1;
    std::unordered_map<std::string, std::string> VirtualFiles_{};
    std::unordered_map<Rml::FileHandle, MetaCoreRmlMemoryFile> OpenFiles_{};
};

struct MetaCoreRmlSharedRuntime {
    [[nodiscard]] bool Acquire(MetaCoreRuntimeUiRenderStats& stats) {
        if (ReferenceCount == 0) {
            FileInterface.Clear();
            Rml::SetSystemInterface(&SystemInterface);
            Rml::SetFileInterface(&FileInterface);
            Rml::SetFontEngineInterface(&FontInterface);
            if (!Rml::Initialise()) {
                stats.LastError = SystemInterface.GetLastMessage().empty()
                    ? "RmlUi core initialization failed"
                    : "RmlUi core initialization failed: " + SystemInterface.GetLastMessage();
                return false;
            }
            Initialized = true;
        }

        ++ReferenceCount;
        stats.RmlInitialized = Initialized;
        return Initialized;
    }

    void Release() {
        if (ReferenceCount == 0) {
            return;
        }

        --ReferenceCount;
        if (ReferenceCount == 0 && Initialized) {
            Rml::Shutdown();
            FileInterface.Clear();
            Initialized = false;
        }
    }

    MetaCoreRmlSystemInterface SystemInterface{};
    MetaCoreRmlMemoryFileInterface FileInterface{};
    Rml::FontEngineInterface FontInterface{};
    std::size_t ReferenceCount = 0;
    bool Initialized = false;
};

[[nodiscard]] MetaCoreRmlSharedRuntime& MetaCoreGetRmlSharedRuntime() {
    static MetaCoreRmlSharedRuntime runtime;
    return runtime;
}

class MetaCoreRmlDiagnosticRenderInterface final : public Rml::RenderInterface {
public:
    MetaCoreRmlDiagnosticRenderInterface(
        MetaCoreRuntimeUiRenderStats& stats,
        MetaCoreRuntimeUiFrame& frame
    )
        : Stats_(stats),
          Frame_(frame) {}

    Rml::CompiledGeometryHandle CompileGeometry(Rml::Span<const Rml::Vertex> vertices, Rml::Span<const int> indices) override {
        const Rml::CompiledGeometryHandle handle = NextGeometryHandle_++;
        MetaCoreRmlGeometryRecord record;
        record.Vertices.reserve(vertices.size());
        for (const Rml::Vertex& vertex : vertices) {
            record.Vertices.push_back(MetaCoreRuntimeUiDrawVertex{
                vertex.position.x,
                vertex.position.y,
                vertex.tex_coord.x,
                vertex.tex_coord.y,
                vertex.colour.red,
                vertex.colour.green,
                vertex.colour.blue,
                vertex.colour.alpha
            });
        }
        record.Indices.reserve(indices.size());
        for (const int index : indices) {
            if (index >= 0) {
                record.Indices.push_back(static_cast<std::uint32_t>(index));
            }
        }

        Geometries_.emplace(handle, std::move(record));
        Stats_.CompiledGeometryCount = Geometries_.size();
        return handle;
    }

    void RenderGeometry(Rml::CompiledGeometryHandle geometry, Rml::Vector2f translation, Rml::TextureHandle texture) override {
        ++Stats_.RenderGeometryCalls;
        const auto geometryIterator = Geometries_.find(geometry);
        if (geometryIterator == Geometries_.end()) {
            return;
        }

        const MetaCoreRmlGeometryRecord& record = geometryIterator->second;
        const std::size_t vertexOffset = Frame_.Vertices.size();
        const std::size_t indexOffset = Frame_.Indices.size();

        Frame_.Vertices.reserve(Frame_.Vertices.size() + record.Vertices.size());
        for (MetaCoreRuntimeUiDrawVertex vertex : record.Vertices) {
            vertex.X += translation.x;
            vertex.Y += translation.y;
            Frame_.Vertices.push_back(vertex);
        }

        Frame_.Indices.reserve(Frame_.Indices.size() + record.Indices.size());
        for (const std::uint32_t index : record.Indices) {
            Frame_.Indices.push_back(static_cast<std::uint32_t>(vertexOffset) + index);
        }

        Frame_.Commands.push_back(MetaCoreRuntimeUiDrawCommand{
            vertexOffset,
            record.Vertices.size(),
            indexOffset,
            record.Indices.size(),
            static_cast<std::uint64_t>(texture),
            ScissorEnabled_,
            ScissorRegion_.Left(),
            ScissorRegion_.Top(),
            ScissorRegion_.Right(),
            ScissorRegion_.Bottom()
        });
        SyncFrameStats();
    }

    void ReleaseGeometry(Rml::CompiledGeometryHandle geometry) override {
        Geometries_.erase(geometry);
        Stats_.CompiledGeometryCount = Geometries_.size();
    }

    Rml::TextureHandle LoadTexture(Rml::Vector2i& textureDimensions, const Rml::String& source) override {
        (void)source;
        ++Stats_.TextureLoadRequests;
        textureDimensions = Rml::Vector2i(0, 0);
        return 0;
    }

    Rml::TextureHandle GenerateTexture(Rml::Span<const Rml::byte> source, Rml::Vector2i sourceDimensions) override {
        ++Stats_.TextureGenerateRequests;
        if (sourceDimensions.x <= 0 || sourceDimensions.y <= 0) {
            return 0;
        }

        const std::size_t width = static_cast<std::size_t>(sourceDimensions.x);
        const std::size_t height = static_cast<std::size_t>(sourceDimensions.y);
        const std::size_t expectedByteCount = width * height * 4U;
        if (expectedByteCount == 0 || source.empty()) {
            return 0;
        }

        const Rml::TextureHandle handle = NextTextureHandle_++;
        MetaCoreRmlTextureRecord record;
        record.Handle = static_cast<std::uint64_t>(handle);
        record.Width = sourceDimensions.x;
        record.Height = sourceDimensions.y;
        record.Revision = NextTextureRevision_++;
        record.Rgba.resize(expectedByteCount, 0);
        const auto* sourceBytes = reinterpret_cast<const std::uint8_t*>(source.data());
        const std::size_t copyByteCount = std::min(expectedByteCount, source.size());
        std::copy(sourceBytes, sourceBytes + copyByteCount, record.Rgba.begin());
        Textures_.emplace(handle, std::move(record));
        return handle;
    }

    void ReleaseTexture(Rml::TextureHandle texture) override {
        Textures_.erase(texture);
    }

    void EnableScissorRegion(bool enable) override {
        ScissorEnabled_ = enable;
    }

    void SetScissorRegion(Rml::Rectanglei region) override {
        ScissorRegion_ = region;
    }

    void BeginFrame() {
        Frame_ = MetaCoreRuntimeUiFrame{};
        SyncFrameStats();
        SyncTextureStats();
    }

    void SyncFrameStats() {
        Stats_.DrawCommandCount = Frame_.Commands.size();
        Stats_.DrawVertexCount = Frame_.Vertices.size();
        Stats_.DrawIndexCount = Frame_.Indices.size();
    }

    void SyncTexturesToFrame() {
        Frame_.Textures.clear();
        Frame_.Textures.reserve(Textures_.size());
        for (const auto& [handle, record] : Textures_) {
            (void)handle;
            if (record.Handle == 0 || record.Width <= 0 || record.Height <= 0 || record.Rgba.empty()) {
                continue;
            }
            Frame_.Textures.push_back(MetaCoreRuntimeUiTexture{
                record.Handle,
                record.Width,
                record.Height,
                record.Revision,
                record.Rgba
            });
        }
        SyncTextureStats();
    }

    void SyncTextureStats() {
        Stats_.TextureCount = Frame_.Textures.size();
        Stats_.TexturePixelCount = 0;
        for (const MetaCoreRuntimeUiTexture& texture : Frame_.Textures) {
            if (texture.Width > 0 && texture.Height > 0) {
                Stats_.TexturePixelCount += static_cast<std::size_t>(texture.Width) * static_cast<std::size_t>(texture.Height);
            }
        }
    }

private:
    struct MetaCoreRmlGeometryRecord {
        std::vector<MetaCoreRuntimeUiDrawVertex> Vertices{};
        std::vector<std::uint32_t> Indices{};
    };

    struct MetaCoreRmlTextureRecord {
        std::uint64_t Handle = 0;
        std::int32_t Width = 0;
        std::int32_t Height = 0;
        std::uint64_t Revision = 0;
        std::vector<std::uint8_t> Rgba{};
    };

    MetaCoreRuntimeUiRenderStats& Stats_;
    MetaCoreRuntimeUiFrame& Frame_;
    Rml::CompiledGeometryHandle NextGeometryHandle_ = 1;
    Rml::TextureHandle NextTextureHandle_ = 1;
    std::uint64_t NextTextureRevision_ = 1;
    std::unordered_map<Rml::CompiledGeometryHandle, MetaCoreRmlGeometryRecord> Geometries_{};
    std::unordered_map<Rml::TextureHandle, MetaCoreRmlTextureRecord> Textures_{};
    bool ScissorEnabled_ = false;
    Rml::Rectanglei ScissorRegion_{};
};

std::uint64_t MetaCoreNextRuntimeUiContextId() {
    static std::uint64_t nextContextId = 1;
    return nextContextId++;
}

}  // namespace

struct MetaCoreRuntimeUiRenderer::MetaCoreRuntimeUiRendererImpl {
    explicit MetaCoreRuntimeUiRendererImpl(MetaCoreRuntimeUiRenderStats& stats)
        : RenderInterface(stats, Frame) {}

    MetaCoreCompiledRmlUiDocument Document{};
    MetaCoreRuntimeUiFrame Frame{};
    MetaCoreRuntimeUiRasterFrame RasterFrame{};
    MetaCoreRmlDiagnosticRenderInterface RenderInterface;
    Rml::Context* Context = nullptr;
    Rml::ElementDocument* LoadedDocument = nullptr;
    std::string ContextName{};
    bool SharedRuntimeAcquired = false;
};

MetaCoreRuntimeUiRenderer::MetaCoreRuntimeUiRenderer() = default;

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

bool MetaCoreRuntimeUiRenderer::Initialize() {
    Shutdown();

    Impl_ = std::make_unique<MetaCoreRuntimeUiRendererImpl>(Stats_);
    Impl_->SharedRuntimeAcquired = MetaCoreGetRmlSharedRuntime().Acquire(Stats_);
    if (!Impl_->SharedRuntimeAcquired) {
        Impl_.reset();
        return false;
    }

    Impl_->ContextName = "MetaCoreRuntimeUi_" + std::to_string(MetaCoreNextRuntimeUiContextId());
    Impl_->Context = Rml::CreateContext(
        Impl_->ContextName,
        Rml::Vector2i(1, 1),
        &Impl_->RenderInterface
    );
    if (Impl_->Context == nullptr) {
        Stats_.LastError = "RmlUi context creation failed";
        MetaCoreGetRmlSharedRuntime().Release();
        Impl_.reset();
        return false;
    }

    Stats_.Initialized = true;
    Stats_.RmlInitialized = true;
    Stats_.RmlContextCreated = true;
    Stats_.RmlDocumentLoaded = false;
    Stats_.LastError.clear();
    return true;
}

void MetaCoreRuntimeUiRenderer::Shutdown() {
    if (Impl_ != nullptr) {
        if (Impl_->Context != nullptr && Impl_->LoadedDocument != nullptr) {
            Impl_->Context->UnloadDocument(Impl_->LoadedDocument);
            Impl_->Context->Update();
            Impl_->LoadedDocument = nullptr;
        }

        if (!Impl_->ContextName.empty()) {
            (void)Rml::RemoveContext(Impl_->ContextName);
            Impl_->Context = nullptr;
        }

        if (Impl_->SharedRuntimeAcquired) {
            Rml::ReleaseCompiledGeometry(&Impl_->RenderInterface);
            Rml::ReleaseTextures(&Impl_->RenderInterface);
            Rml::ReleaseRenderManagers();
            MetaCoreGetRmlSharedRuntime().Release();
            Impl_->SharedRuntimeAcquired = false;
        }
    }

    Impl_.reset();
    Stats_ = MetaCoreRuntimeUiRenderStats{};
}

bool MetaCoreRuntimeUiRenderer::LoadCompiledDocument(const MetaCoreCompiledRmlUiDocument& document) {
    if (!Stats_.Initialized || Impl_ == nullptr || Impl_->Context == nullptr) {
        Stats_.LastError = "Runtime UI renderer is not initialized";
        return false;
    }

    if (document.Rml.empty()) {
        Stats_.Loaded = false;
        Stats_.RmlDocumentLoaded = false;
        Stats_.RmlBytes = 0;
        Stats_.RcssBytes = 0;
        Stats_.LastError = "Compiled runtime UI RML is empty";
        return false;
    }

    if (Impl_->LoadedDocument != nullptr) {
        Impl_->Context->UnloadDocument(Impl_->LoadedDocument);
        Impl_->Context->Update();
        Impl_->LoadedDocument = nullptr;
    }

    Impl_->Document = document;
    const std::string stylesheetHref = Impl_->Document.StylesheetHref.empty()
        ? "MetaCoreRuntimeUi.rcss"
        : Impl_->Document.StylesheetHref;
    MetaCoreGetRmlSharedRuntime().FileInterface.SetVirtualFile(stylesheetHref, Impl_->Document.Rcss);

    Impl_->LoadedDocument = Impl_->Context->LoadDocumentFromMemory(
        Impl_->Document.Rml,
        "MetaCoreRuntimeUi.rml"
    );
    if (Impl_->LoadedDocument == nullptr) {
        Stats_.Loaded = false;
        Stats_.RmlDocumentLoaded = false;
        Stats_.LastError = "RmlUi failed to load compiled runtime UI document";
        return false;
    }

    Impl_->LoadedDocument->Show(Rml::ModalFlag::None, Rml::FocusFlag::None);
    Impl_->Context->Update();

    Stats_.Loaded = true;
    Stats_.RmlDocumentLoaded = true;
    Stats_.RmlBytes = Impl_->Document.Rml.size();
    Stats_.RcssBytes = Impl_->Document.Rcss.size();
    Stats_.LastError.clear();
    return true;
}

bool MetaCoreRuntimeUiRenderer::HasNode(std::string_view nodeId) const {
    if (!Stats_.Initialized || !Stats_.Loaded || Impl_ == nullptr || Impl_->LoadedDocument == nullptr) {
        return false;
    }

    const std::string elementId = MetaCoreBuildRuntimeUiNodeElementId(nodeId);
    return Impl_->LoadedDocument->GetElementById(elementId) != nullptr;
}

bool MetaCoreRuntimeUiRenderer::SetNodeText(std::string_view nodeId, std::string_view text) {
    if (!Stats_.Initialized || !Stats_.Loaded || Impl_ == nullptr || Impl_->LoadedDocument == nullptr) {
        Stats_.LastError = "Runtime UI document is not loaded";
        return false;
    }

    const std::string elementId = MetaCoreBuildRuntimeUiNodeElementId(nodeId);
    Rml::Element* element = Impl_->LoadedDocument->GetElementById(elementId);
    if (element == nullptr) {
        Stats_.LastError = "Runtime UI node was not found: " + std::string(nodeId);
        return false;
    }

    element->SetInnerRML(MetaCoreEscapeRuntimeUiRmlText(text));
    if (Impl_->Context != nullptr) {
        Impl_->Context->Update();
    }
    Stats_.LastError.clear();
    return true;
}

void MetaCoreRuntimeUiRenderer::Resize(std::int32_t width, std::int32_t height) {
    Stats_.Width = std::max<std::int32_t>(0, width);
    Stats_.Height = std::max<std::int32_t>(0, height);
    if (Impl_ != nullptr && Impl_->Context != nullptr) {
        Impl_->Context->SetDimensions(Rml::Vector2i(
            std::max<std::int32_t>(1, width),
            std::max<std::int32_t>(1, height)
        ));
    }
}

void MetaCoreRuntimeUiRenderer::BeginFrame(float deltaSeconds) {
    if (!Stats_.Initialized) {
        return;
    }

    Stats_.LastDeltaSeconds = deltaSeconds;
    ++Stats_.FrameCount;
    MetaCoreGetRmlSharedRuntime().SystemInterface.Advance(deltaSeconds);

    if (Impl_ != nullptr && Impl_->Context != nullptr) {
        Impl_->Context->Update();
    }
}

void MetaCoreRuntimeUiRenderer::Render() {
    if (!Stats_.Initialized || !Stats_.Loaded || Impl_ == nullptr || Impl_->Context == nullptr) {
        return;
    }

    Impl_->RenderInterface.BeginFrame();
    if (!Impl_->Context->Render()) {
        Stats_.LastError = "RmlUi context render failed";
    }
    Impl_->RenderInterface.SyncTexturesToFrame();
    MetaCoreRuntimeUiRasterizeFrame(
        Impl_->Frame,
        Impl_->RasterFrame,
        Stats_,
        Stats_.Width,
        Stats_.Height
    );
}

const MetaCoreRuntimeUiRenderStats& MetaCoreRuntimeUiRenderer::GetStats() const {
    return Stats_;
}

const MetaCoreRuntimeUiFrame& MetaCoreRuntimeUiRenderer::GetLastFrame() const {
    static const MetaCoreRuntimeUiFrame emptyFrame{};
    return Impl_ == nullptr ? emptyFrame : Impl_->Frame;
}

const MetaCoreRuntimeUiRasterFrame& MetaCoreRuntimeUiRenderer::GetLastRasterFrame() const {
    static const MetaCoreRuntimeUiRasterFrame emptyRasterFrame{};
    return Impl_ == nullptr ? emptyRasterFrame : Impl_->RasterFrame;
}

}  // namespace MetaCore