#include <XCNewEditor/Host/NativeRenderer.h>

#include <algorithm>
#include <cmath>
#include <filesystem>

namespace XCEngine::XCUI::Host {

namespace {

D2D1_RECT_F ToD2DRect(const ::XCEngine::UI::UIRect& rect) {
    return D2D1::RectF(rect.x, rect.y, rect.x + rect.width, rect.y + rect.height);
}

std::string HrToString(const char* operation, HRESULT hr) {
    char buffer[128] = {};
    sprintf_s(buffer, "%s failed with hr=0x%08X.", operation, static_cast<unsigned int>(hr));
    return buffer;
}

} // namespace

bool NativeRenderer::Initialize(HWND hwnd) {
    Shutdown();

    if (hwnd == nullptr) {
        return false;
    }

    m_hwnd = hwnd;
    if (FAILED(D2D1CreateFactory(D2D1_FACTORY_TYPE_SINGLE_THREADED, m_d2dFactory.ReleaseAndGetAddressOf()))) {
        Shutdown();
        return false;
    }

    if (FAILED(DWriteCreateFactory(
            DWRITE_FACTORY_TYPE_SHARED,
            __uuidof(IDWriteFactory),
            reinterpret_cast<IUnknown**>(m_dwriteFactory.ReleaseAndGetAddressOf())))) {
        Shutdown();
        return false;
    }

    return EnsureRenderTarget();
}

void NativeRenderer::Shutdown() {
    m_textFormats.clear();
    m_solidBrush.Reset();
    m_renderTarget.Reset();
    m_wicFactory.Reset();
    m_dwriteFactory.Reset();
    m_d2dFactory.Reset();
    if (m_wicComInitialized) {
        CoUninitialize();
        m_wicComInitialized = false;
    }
    m_hwnd = nullptr;
}

void NativeRenderer::Resize(UINT width, UINT height) {
    if (!m_renderTarget || width == 0 || height == 0) {
        return;
    }

    const HRESULT hr = m_renderTarget->Resize(D2D1::SizeU(width, height));
    if (hr == D2DERR_RECREATE_TARGET) {
        DiscardRenderTarget();
    }
}

bool NativeRenderer::Render(const ::XCEngine::UI::UIDrawData& drawData) {
    if (!EnsureRenderTarget()) {
        return false;
    }

    const bool rendered = RenderToTarget(*m_renderTarget.Get(), *m_solidBrush.Get(), drawData);
    const HRESULT hr = m_renderTarget->EndDraw();
    if (hr == D2DERR_RECREATE_TARGET) {
        DiscardRenderTarget();
        return false;
    }

    return rendered && SUCCEEDED(hr);
}

bool NativeRenderer::CaptureToPng(
    const ::XCEngine::UI::UIDrawData& drawData,
    UINT width,
    UINT height,
    const std::filesystem::path& outputPath,
    std::string& outError) {
    outError.clear();
    if (width == 0 || height == 0) {
        outError = "CaptureToPng rejected an empty render size.";
        return false;
    }

    if (!m_d2dFactory || !m_dwriteFactory) {
        outError = "CaptureToPng requires an initialized NativeRenderer.";
        return false;
    }

    if (!EnsureWicFactory(outError)) {
        return false;
    }

    std::error_code errorCode = {};
    std::filesystem::create_directories(outputPath.parent_path(), errorCode);
    if (errorCode) {
        outError = "Failed to create screenshot directory: " + outputPath.parent_path().string();
        return false;
    }

    Microsoft::WRL::ComPtr<IWICBitmap> bitmap;
    HRESULT hr = m_wicFactory->CreateBitmap(
        width,
        height,
        GUID_WICPixelFormat32bppPBGRA,
        WICBitmapCacheOnLoad,
        bitmap.ReleaseAndGetAddressOf());
    if (FAILED(hr)) {
        outError = HrToString("IWICImagingFactory::CreateBitmap", hr);
        return false;
    }

    const D2D1_RENDER_TARGET_PROPERTIES renderTargetProperties = D2D1::RenderTargetProperties(
        D2D1_RENDER_TARGET_TYPE_DEFAULT,
        D2D1::PixelFormat(DXGI_FORMAT_B8G8R8A8_UNORM, D2D1_ALPHA_MODE_PREMULTIPLIED));

    Microsoft::WRL::ComPtr<ID2D1RenderTarget> offscreenRenderTarget;
    hr = m_d2dFactory->CreateWicBitmapRenderTarget(
        bitmap.Get(),
        renderTargetProperties,
        offscreenRenderTarget.ReleaseAndGetAddressOf());
    if (FAILED(hr)) {
        outError = HrToString("ID2D1Factory::CreateWicBitmapRenderTarget", hr);
        return false;
    }

    Microsoft::WRL::ComPtr<ID2D1SolidColorBrush> offscreenBrush;
    hr = offscreenRenderTarget->CreateSolidColorBrush(
        D2D1::ColorF(1.0f, 1.0f, 1.0f, 1.0f),
        offscreenBrush.ReleaseAndGetAddressOf());
    if (FAILED(hr)) {
        outError = HrToString("ID2D1RenderTarget::CreateSolidColorBrush", hr);
        return false;
    }

    const bool rendered = RenderToTarget(*offscreenRenderTarget.Get(), *offscreenBrush.Get(), drawData);
    hr = offscreenRenderTarget->EndDraw();
    if (!rendered || FAILED(hr)) {
        outError = HrToString("ID2D1RenderTarget::EndDraw", hr);
        return false;
    }

    const std::wstring wideOutputPath = outputPath.wstring();
    Microsoft::WRL::ComPtr<IWICStream> stream;
    hr = m_wicFactory->CreateStream(stream.ReleaseAndGetAddressOf());
    if (FAILED(hr)) {
        outError = HrToString("IWICImagingFactory::CreateStream", hr);
        return false;
    }

    hr = stream->InitializeFromFilename(wideOutputPath.c_str(), GENERIC_WRITE);
    if (FAILED(hr)) {
        outError = HrToString("IWICStream::InitializeFromFilename", hr);
        return false;
    }

    Microsoft::WRL::ComPtr<IWICBitmapEncoder> encoder;
    hr = m_wicFactory->CreateEncoder(GUID_ContainerFormatPng, nullptr, encoder.ReleaseAndGetAddressOf());
    if (FAILED(hr)) {
        outError = HrToString("IWICImagingFactory::CreateEncoder", hr);
        return false;
    }

    hr = encoder->Initialize(stream.Get(), WICBitmapEncoderNoCache);
    if (FAILED(hr)) {
        outError = HrToString("IWICBitmapEncoder::Initialize", hr);
        return false;
    }

    Microsoft::WRL::ComPtr<IWICBitmapFrameEncode> frame;
    Microsoft::WRL::ComPtr<IPropertyBag2> propertyBag;
    hr = encoder->CreateNewFrame(frame.ReleaseAndGetAddressOf(), propertyBag.ReleaseAndGetAddressOf());
    if (FAILED(hr)) {
        outError = HrToString("IWICBitmapEncoder::CreateNewFrame", hr);
        return false;
    }

    hr = frame->Initialize(propertyBag.Get());
    if (FAILED(hr)) {
        outError = HrToString("IWICBitmapFrameEncode::Initialize", hr);
        return false;
    }

    hr = frame->SetSize(width, height);
    if (FAILED(hr)) {
        outError = HrToString("IWICBitmapFrameEncode::SetSize", hr);
        return false;
    }

    WICPixelFormatGUID pixelFormat = GUID_WICPixelFormat32bppPBGRA;
    hr = frame->SetPixelFormat(&pixelFormat);
    if (FAILED(hr)) {
        outError = HrToString("IWICBitmapFrameEncode::SetPixelFormat", hr);
        return false;
    }

    hr = frame->WriteSource(bitmap.Get(), nullptr);
    if (FAILED(hr)) {
        outError = HrToString("IWICBitmapFrameEncode::WriteSource", hr);
        return false;
    }

    hr = frame->Commit();
    if (FAILED(hr)) {
        outError = HrToString("IWICBitmapFrameEncode::Commit", hr);
        return false;
    }

    hr = encoder->Commit();
    if (FAILED(hr)) {
        outError = HrToString("IWICBitmapEncoder::Commit", hr);
        return false;
    }

    return true;
}

bool NativeRenderer::EnsureRenderTarget() {
    if (!m_hwnd || !m_d2dFactory || !m_dwriteFactory) {
        return false;
    }

    return CreateDeviceResources();
}

bool NativeRenderer::EnsureWicFactory(std::string& outError) {
    outError.clear();
    if (m_wicFactory) {
        return true;
    }

    const HRESULT initHr = CoInitializeEx(nullptr, COINIT_MULTITHREADED);
    if (FAILED(initHr) && initHr != RPC_E_CHANGED_MODE) {
        outError = HrToString("CoInitializeEx", initHr);
        return false;
    }
    if (SUCCEEDED(initHr)) {
        m_wicComInitialized = true;
    }

    const HRESULT factoryHr = CoCreateInstance(
        CLSID_WICImagingFactory,
        nullptr,
        CLSCTX_INPROC_SERVER,
        IID_PPV_ARGS(m_wicFactory.ReleaseAndGetAddressOf()));
    if (FAILED(factoryHr)) {
        outError = HrToString("CoCreateInstance(CLSID_WICImagingFactory)", factoryHr);
        return false;
    }

    return true;
}

void NativeRenderer::DiscardRenderTarget() {
    m_solidBrush.Reset();
    m_renderTarget.Reset();
}

bool NativeRenderer::CreateDeviceResources() {
    if (m_renderTarget) {
        return true;
    }

    RECT clientRect = {};
    GetClientRect(m_hwnd, &clientRect);
    const UINT width = static_cast<UINT>((std::max)(clientRect.right - clientRect.left, 1L));
    const UINT height = static_cast<UINT>((std::max)(clientRect.bottom - clientRect.top, 1L));

    const D2D1_RENDER_TARGET_PROPERTIES renderTargetProps = D2D1::RenderTargetProperties();
    const D2D1_HWND_RENDER_TARGET_PROPERTIES hwndProps = D2D1::HwndRenderTargetProperties(
        m_hwnd,
        D2D1::SizeU(width, height));

    if (FAILED(m_d2dFactory->CreateHwndRenderTarget(
            renderTargetProps,
            hwndProps,
            m_renderTarget.ReleaseAndGetAddressOf()))) {
        return false;
    }

    if (FAILED(m_renderTarget->CreateSolidColorBrush(
            D2D1::ColorF(1.0f, 1.0f, 1.0f, 1.0f),
            m_solidBrush.ReleaseAndGetAddressOf()))) {
        DiscardRenderTarget();
        return false;
    }

    m_renderTarget->SetTextAntialiasMode(D2D1_TEXT_ANTIALIAS_MODE_GRAYSCALE);
    return true;
}

bool NativeRenderer::RenderToTarget(
    ID2D1RenderTarget& renderTarget,
    ID2D1SolidColorBrush& solidBrush,
    const ::XCEngine::UI::UIDrawData& drawData) {
    renderTarget.SetTextAntialiasMode(D2D1_TEXT_ANTIALIAS_MODE_GRAYSCALE);
    renderTarget.BeginDraw();
    renderTarget.Clear(D2D1::ColorF(0.04f, 0.05f, 0.06f, 1.0f));

    std::vector<D2D1_RECT_F> clipStack = {};
    for (const ::XCEngine::UI::UIDrawList& drawList : drawData.GetDrawLists()) {
        for (const ::XCEngine::UI::UIDrawCommand& command : drawList.GetCommands()) {
            RenderCommand(renderTarget, solidBrush, command, clipStack);
        }
    }

    while (!clipStack.empty()) {
        renderTarget.PopAxisAlignedClip();
        clipStack.pop_back();
    }

    return true;
}

void NativeRenderer::RenderCommand(
    ID2D1RenderTarget& renderTarget,
    ID2D1SolidColorBrush& solidBrush,
    const ::XCEngine::UI::UIDrawCommand& command,
    std::vector<D2D1_RECT_F>& clipStack) {
    solidBrush.SetColor(ToD2DColor(command.color));

    switch (command.type) {
    case ::XCEngine::UI::UIDrawCommandType::FilledRect: {
        const D2D1_RECT_F rect = ToD2DRect(command.rect);
        if (command.rounding > 0.0f) {
            renderTarget.FillRoundedRectangle(
                D2D1::RoundedRect(rect, command.rounding, command.rounding),
                &solidBrush);
        } else {
            renderTarget.FillRectangle(rect, &solidBrush);
        }
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::RectOutline: {
        const D2D1_RECT_F rect = ToD2DRect(command.rect);
        const float thickness = command.thickness > 0.0f ? command.thickness : 1.0f;
        if (command.rounding > 0.0f) {
            renderTarget.DrawRoundedRectangle(
                D2D1::RoundedRect(rect, command.rounding, command.rounding),
                &solidBrush,
                thickness);
        } else {
            renderTarget.DrawRectangle(rect, &solidBrush, thickness);
        }
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::Text: {
        if (command.text.empty()) {
            break;
        }

        const float fontSize = command.fontSize > 0.0f ? command.fontSize : 16.0f;
        IDWriteTextFormat* textFormat = GetTextFormat(fontSize);
        if (textFormat == nullptr) {
            break;
        }

        const std::wstring text = Utf8ToWide(command.text);
        if (text.empty()) {
            break;
        }

        const D2D1_SIZE_F targetSize = renderTarget.GetSize();
        const D2D1_RECT_F layoutRect = D2D1::RectF(
            command.position.x,
            command.position.y,
            targetSize.width,
            command.position.y + fontSize * 1.8f);
        renderTarget.DrawTextW(
            text.c_str(),
            static_cast<UINT32>(text.size()),
            textFormat,
            layoutRect,
            &solidBrush,
            D2D1_DRAW_TEXT_OPTIONS_CLIP,
            DWRITE_MEASURING_MODE_NATURAL);
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::Image: {
        if (!command.texture.IsValid()) {
            break;
        }

        const D2D1_RECT_F rect = ToD2DRect(command.rect);
        renderTarget.DrawRectangle(rect, &solidBrush, 1.0f);
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::PushClipRect: {
        const D2D1_RECT_F rect = ToD2DRect(command.rect);
        renderTarget.PushAxisAlignedClip(rect, D2D1_ANTIALIAS_MODE_PER_PRIMITIVE);
        clipStack.push_back(rect);
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::PopClipRect: {
        if (!clipStack.empty()) {
            renderTarget.PopAxisAlignedClip();
            clipStack.pop_back();
        }
        break;
    }
    default:
        break;
    }
}

IDWriteTextFormat* NativeRenderer::GetTextFormat(float fontSize) {
    if (!m_dwriteFactory) {
        return nullptr;
    }

    const int key = static_cast<int>(std::lround(fontSize * 10.0f));
    const auto found = m_textFormats.find(key);
    if (found != m_textFormats.end()) {
        return found->second.Get();
    }

    Microsoft::WRL::ComPtr<IDWriteTextFormat> textFormat;
    const HRESULT hr = m_dwriteFactory->CreateTextFormat(
        L"Segoe UI",
        nullptr,
        DWRITE_FONT_WEIGHT_REGULAR,
        DWRITE_FONT_STYLE_NORMAL,
        DWRITE_FONT_STRETCH_NORMAL,
        fontSize,
        L"",
        textFormat.ReleaseAndGetAddressOf());
    if (FAILED(hr)) {
        return nullptr;
    }

    textFormat->SetTextAlignment(DWRITE_TEXT_ALIGNMENT_LEADING);
    textFormat->SetParagraphAlignment(DWRITE_PARAGRAPH_ALIGNMENT_NEAR);
    textFormat->SetWordWrapping(DWRITE_WORD_WRAPPING_NO_WRAP);

    IDWriteTextFormat* result = textFormat.Get();
    m_textFormats.emplace(key, std::move(textFormat));
    return result;
}

D2D1_COLOR_F NativeRenderer::ToD2DColor(const ::XCEngine::UI::UIColor& color) {
    return D2D1::ColorF(color.r, color.g, color.b, color.a);
}

std::wstring NativeRenderer::Utf8ToWide(std::string_view text) {
    if (text.empty()) {
        return {};
    }

    const int sizeNeeded = MultiByteToWideChar(
        CP_UTF8,
        0,
        text.data(),
        static_cast<int>(text.size()),
        nullptr,
        0);
    if (sizeNeeded <= 0) {
        return {};
    }

    std::wstring wideText(static_cast<size_t>(sizeNeeded), L'\0');
    MultiByteToWideChar(
        CP_UTF8,
        0,
        text.data(),
        static_cast<int>(text.size()),
        wideText.data(),
        sizeNeeded);
    return wideText;
}

} // namespace XCEngine::XCUI::Host