/*
  ==============================================================================

   This file is part of the JUCE framework.
   Copyright (c) Raw Material Software Limited

   JUCE is an open source framework subject to commercial or open source
   licensing.

   By downloading, installing, or using the JUCE framework, or combining the
   JUCE framework with any other source code, object code, content or any other
   copyrightable work, you agree to the terms of the JUCE End User Licence
   Agreement, and all incorporated terms including the JUCE Privacy Policy and
   the JUCE Website Terms of Service, as applicable, which will bind you. If you
   do not agree to the terms of these agreements, we will not license the JUCE
   framework to you, and you must discontinue the installation or download
   process and cease use of the JUCE framework.

   JUCE End User Licence Agreement: https://juce.com/legal/juce-8-licence/
   JUCE Privacy Policy: https://juce.com/juce-privacy-policy
   JUCE Website Terms of Service: https://juce.com/juce-website-terms-of-service/

   Or:

   You may also use this code under the terms of the AGPLv3:
   https://www.gnu.org/licenses/agpl-3.0.en.html

   THE JUCE FRAMEWORK IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL
   WARRANTIES, WHETHER EXPRESSED OR IMPLIED, INCLUDING WARRANTY OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, ARE DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

class Direct2DGraphicsContext : public LowLevelGraphicsContext
{
public:
    Direct2DGraphicsContext();
    ~Direct2DGraphicsContext() override;

    //==============================================================================
    bool isVectorDevice() const override { return false; }

    void setOrigin (Point<int>) override;
    void addTransform (const AffineTransform&) override;
    float getPhysicalPixelScaleFactor() const override;
    bool clipToRectangle (const Rectangle<int>&) override;
    bool clipToRectangleList (const RectangleList<int>&) override;
    void excludeClipRectangle (const Rectangle<int>&) override;
    void clipToPath (const Path&, const AffineTransform&) override;
    void clipToImageAlpha (const Image&, const AffineTransform&) override;
    bool clipRegionIntersects (const Rectangle<int>&) override;
    Rectangle<int> getClipBounds() const override;
    bool isClipEmpty() const override;

    //==============================================================================
    void saveState() override;
    void restoreState() override;
    void beginTransparencyLayer (float opacity) override;
    void endTransparencyLayer() override;

    //==============================================================================
    void setFill (const FillType&) override;
    void setOpacity (float) override;
    void setInterpolationQuality (Graphics::ResamplingQuality) override;

    //==============================================================================
    void fillRect (const Rectangle<int>&, bool replaceExistingContents) override;
    void fillRect (const Rectangle<float>&) override;
    void fillRectList (const RectangleList<float>&) override;
    void fillPath (const Path&, const AffineTransform&) override;
    void drawImage (const Image& sourceImage, const AffineTransform&) override;

    //==============================================================================
    void drawLine (const Line<float>&) override;
    void setFont (const Font&) override;
    const Font& getFont() override;
    void drawGlyphs (Span<const uint16_t>,
                     Span<const Point<float>>,
                     const AffineTransform&) override;

    //==============================================================================
    // These methods were not originally part of the LowLevelGraphicsContext; they
    // were added because Direct2D supports these drawing primitives directly.
    // The specialised functions are more efficient than emulating the same behaviour, e.g.
    // by drawing paths.
    void drawLineWithThickness (const Line<float>&, float) override;

    void drawEllipse (const Rectangle<float>& area, float lineThickness) override;
    void fillEllipse (const Rectangle<float>& area) override;

    void drawRect (const Rectangle<float>&, float) override;
    void strokePath (const Path&, const PathStrokeType& strokeType, const AffineTransform&) override;

    void drawRoundedRectangle (const Rectangle<float>& area, float cornerSize, float lineThickness) override;
    void fillRoundedRectangle (const Rectangle<float>& area, float cornerSize) override;

    //==============================================================================
    bool startFrame (float dpiScale);
    void endFrame();

    virtual Image createSnapshot() const { return {}; }

    uint64_t getFrameId() const override { return frame; }

    std::unique_ptr<ImageType> getPreferredImageTypeForTemporaryImages() const override
    {
        return std::make_unique<NativeImageType>();
    }

    Direct2DMetrics::Ptr metrics;

protected:
    template <typename Shape, typename Fn>
    void paintPrimitive (const Shape& shape, Fn&& primitiveOp);

    static Line<float> offsetShape (Line<float> a, Point<float> b);
    static Rectangle<float> offsetShape (Rectangle<float> a, Point<float> b);
    static RectangleList<float> offsetShape (RectangleList<float> a, Point<float> b);

    struct SavedState;
    SavedState* currentState = nullptr;

    class PendingClipList
    {
    public:
        void clipTo (Rectangle<float> i)
        {
            if (std::exchange (clipApplied, true))
                list.clipTo (i);
            else
                list = i;
        }

        template <typename Numeric>
        void clipTo (const RectangleList<Numeric>& other)
        {
            if (std::exchange (clipApplied, true))
            {
                list.clipTo (other);
            }
            else
            {
                list.clear();

                for (const auto& r : other)
                    list.add (r.toFloat());
            }
        }

        void subtract (Rectangle<float> i)
        {
            list.subtract (i);
            clipApplied = true;
        }

        RectangleList<float> getList() const { return list; }
        bool isClipApplied() const { return clipApplied; }

        void reset (Rectangle<float> maxBounds)
        {
            list = maxBounds;
            clipApplied = false;
        }

    private:
        RectangleList<float> list;
        bool clipApplied = false;
    };

    PendingClipList pendingClipList;

    struct Pimpl;
    virtual Pimpl* getPimpl() const noexcept = 0;

    void resetPendingClipList();
    void applyPendingClipList();
    virtual void clearTargetBuffer() = 0;

    struct ScopedTransform
    {
        ScopedTransform (Pimpl&, SavedState*);
        ScopedTransform (Pimpl&, SavedState*, const AffineTransform& transform);
        ~ScopedTransform();

        Pimpl& pimpl;
        SavedState* state = nullptr;
    };

    uint64_t frame = 0;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (Direct2DGraphicsContext)
};

} // namespace juce