#include "NativeRendererSupport.h"

#include <algorithm>
#include <cmath>

namespace XCEngine::UI::Editor::Host {

using namespace NativeRendererSupport;

bool NativeRenderer::RenderToTarget(
    ID2D1RenderTarget& renderTarget,
    ID2D1SolidColorBrush& solidBrush,
    const ::XCEngine::UI::UIDrawData& drawData) {
    renderTarget.SetDpi(kBaseDpi, kBaseDpi);
    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));
    const float dpiScale = ClampDpiScale(m_dpiScale);

    switch (command.type) {
    case ::XCEngine::UI::UIDrawCommandType::FilledRect: {
        const D2D1_RECT_F rect = ToD2DRect(command.rect, dpiScale);
        const float rounding = command.rounding > 0.0f ? command.rounding * dpiScale : 0.0f;
        if (command.rounding > 0.0f) {
            renderTarget.FillRoundedRectangle(
                D2D1::RoundedRect(rect, rounding, rounding),
                &solidBrush);
        } else {
            renderTarget.FillRectangle(rect, &solidBrush);
        }
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::FilledRectLinearGradient: {
        const D2D1_RECT_F rect = ToD2DRect(command.rect, dpiScale);
        const float rounding = command.rounding > 0.0f ? command.rounding * dpiScale : 0.0f;

        const D2D1_GRADIENT_STOP stops[2] = {
            D2D1::GradientStop(0.0f, ToD2DColor(command.color)),
            D2D1::GradientStop(1.0f, ToD2DColor(command.secondaryColor))
        };

        Microsoft::WRL::ComPtr<ID2D1GradientStopCollection> stopCollection;
        HRESULT hr = renderTarget.CreateGradientStopCollection(
            stops,
            2u,
            stopCollection.ReleaseAndGetAddressOf());
        if (FAILED(hr) || !stopCollection) {
            break;
        }

        const D2D1_POINT_2F startPoint =
            command.gradientDirection == ::XCEngine::UI::UILinearGradientDirection::Vertical
                ? D2D1::Point2F((rect.left + rect.right) * 0.5f, rect.top)
                : D2D1::Point2F(rect.left, (rect.top + rect.bottom) * 0.5f);
        const D2D1_POINT_2F endPoint =
            command.gradientDirection == ::XCEngine::UI::UILinearGradientDirection::Vertical
                ? D2D1::Point2F((rect.left + rect.right) * 0.5f, rect.bottom)
                : D2D1::Point2F(rect.right, (rect.top + rect.bottom) * 0.5f);

        Microsoft::WRL::ComPtr<ID2D1LinearGradientBrush> gradientBrush;
        hr = renderTarget.CreateLinearGradientBrush(
            D2D1::LinearGradientBrushProperties(startPoint, endPoint),
            stopCollection.Get(),
            gradientBrush.ReleaseAndGetAddressOf());
        if (FAILED(hr) || !gradientBrush) {
            break;
        }

        if (command.rounding > 0.0f) {
            renderTarget.FillRoundedRectangle(
                D2D1::RoundedRect(rect, rounding, rounding),
                gradientBrush.Get());
        } else {
            renderTarget.FillRectangle(rect, gradientBrush.Get());
        }
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::RectOutline: {
        const D2D1_RECT_F rect = ToD2DRect(command.rect, dpiScale);
        const float thickness = (command.thickness > 0.0f ? command.thickness : 1.0f) * dpiScale;
        const float rounding = command.rounding > 0.0f ? command.rounding * dpiScale : 0.0f;
        if (command.rounding > 0.0f) {
            renderTarget.DrawRoundedRectangle(
                D2D1::RoundedRect(rect, rounding, rounding),
                &solidBrush,
                thickness);
        } else {
            renderTarget.DrawRectangle(rect, &solidBrush, thickness);
        }
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::Line: {
        const float thickness = (command.thickness > 0.0f ? command.thickness : 1.0f) * dpiScale;
        const float pixelOffset = ResolveStrokePixelOffset(thickness);
        const D2D1_POINT_2F start = ToD2DPoint(command.position, dpiScale, pixelOffset);
        const D2D1_POINT_2F end = ToD2DPoint(command.uvMin, dpiScale, pixelOffset);
        renderTarget.DrawLine(start, end, &solidBrush, thickness);
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::FilledTriangle: {
        Microsoft::WRL::ComPtr<ID2D1PathGeometry> geometry;
        HRESULT hr = m_d2dFactory->CreatePathGeometry(geometry.ReleaseAndGetAddressOf());
        if (FAILED(hr) || !geometry) {
            break;
        }

        Microsoft::WRL::ComPtr<ID2D1GeometrySink> sink;
        hr = geometry->Open(sink.ReleaseAndGetAddressOf());
        if (FAILED(hr) || !sink) {
            break;
        }

        const D2D1_POINT_2F a = ToD2DPoint(command.position, dpiScale);
        const D2D1_POINT_2F b = ToD2DPoint(command.uvMin, dpiScale);
        const D2D1_POINT_2F c = ToD2DPoint(command.uvMax, dpiScale);
        const D2D1_POINT_2F points[2] = { b, c };
        sink->BeginFigure(a, D2D1_FIGURE_BEGIN_FILLED);
        sink->AddLines(points, 2u);
        sink->EndFigure(D2D1_FIGURE_END_CLOSED);
        hr = sink->Close();
        if (FAILED(hr)) {
            break;
        }

        renderTarget.FillGeometry(geometry.Get(), &solidBrush);
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::FilledCircle: {
        const float radius = command.radius * dpiScale;
        renderTarget.FillEllipse(
            D2D1::Ellipse(ToD2DPoint(command.position, dpiScale), radius, radius),
            &solidBrush);
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::CircleOutline: {
        const float radius = command.radius * dpiScale;
        const float thickness = (command.thickness > 0.0f ? command.thickness : 1.0f) * dpiScale;
        renderTarget.DrawEllipse(
            D2D1::Ellipse(ToD2DPoint(command.position, dpiScale), radius, radius),
            &solidBrush,
            thickness);
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::Text: {
        if (command.text.empty()) {
            break;
        }

        const float fontSize = ResolveFontSize(command.fontSize);
        const float scaledFontSize = fontSize * dpiScale;
        IDWriteTextFormat* textFormat = GetTextFormat(scaledFontSize);
        if (textFormat == nullptr) {
            break;
        }

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

        const D2D1_SIZE_F targetSize = renderTarget.GetSize();
        const float originX = SnapToPixel(command.position.x, dpiScale);
        const float originY = SnapToPixel(command.position.y, dpiScale);
        const float lineHeight = std::ceil(scaledFontSize * 1.6f);
        const D2D1_RECT_F layoutRect = D2D1::RectF(
            originX,
            originY,
            targetSize.width,
            originY + lineHeight);
        renderTarget.DrawTextW(
            text.c_str(),
            static_cast<UINT32>(text.size()),
            textFormat,
            layoutRect,
            &solidBrush,
            D2D1_DRAW_TEXT_OPTIONS_CLIP,
            DWRITE_MEASURING_MODE_GDI_NATURAL);
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::Image: {
        if (!command.texture.IsValid()) {
            break;
        }

        Microsoft::WRL::ComPtr<ID2D1Bitmap> bitmap;
        if (command.texture.kind == ::XCEngine::UI::UITextureHandleKind::ShaderResourceView) {
            if (!ResolveInteropBitmap(command.texture, bitmap) || !bitmap) {
                const D2D1_RECT_F rect = ToD2DRect(command.rect, dpiScale);
                renderTarget.DrawRectangle(rect, &solidBrush, 1.0f);
                break;
            }
        } else {
            auto* texture = reinterpret_cast<NativeTextureResource*>(command.texture.nativeHandle);
            if (texture == nullptr || m_liveTextures.find(texture) == m_liveTextures.end()) {
                const D2D1_RECT_F rect = ToD2DRect(command.rect, dpiScale);
                renderTarget.DrawRectangle(rect, &solidBrush, 1.0f);
                break;
            }

            if (!ResolveTextureBitmap(renderTarget, *texture, bitmap) || !bitmap) {
                break;
            }
        }

        const D2D1_RECT_F rect = ToD2DRect(command.rect, dpiScale);
        const float sourceWidth = static_cast<float>(command.texture.width);
        const float sourceHeight = static_cast<float>(command.texture.height);
        const float sourceLeft = sourceWidth * std::clamp(command.uvMin.x, 0.0f, 1.0f);
        const float sourceTop = sourceHeight * std::clamp(command.uvMin.y, 0.0f, 1.0f);
        const float sourceRight = sourceWidth * std::clamp(command.uvMax.x, 0.0f, 1.0f);
        const float sourceBottom = sourceHeight * std::clamp(command.uvMax.y, 0.0f, 1.0f);
        renderTarget.DrawBitmap(
            bitmap.Get(),
            rect,
            std::clamp(command.color.a, 0.0f, 1.0f),
            D2D1_BITMAP_INTERPOLATION_MODE_LINEAR,
            D2D1::RectF(sourceLeft, sourceTop, sourceRight, sourceBottom));
        break;
    }
    case ::XCEngine::UI::UIDrawCommandType::PushClipRect: {
        const D2D1_RECT_F rect = ToD2DRect(command.rect, dpiScale);
        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;
    }
}

} // namespace XCEngine::UI::Editor::Host