/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
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 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
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 */

#pragma once

#include <drawinglayer/drawinglayerdllapi.h>

#include <drawinglayer/primitive2d/BufferedDecompositionGroupPrimitive2D.hxx>
#include <basegfx/color/bcolor.hxx>
#include <basegfx/matrix/b2dhommatrix.hxx>

namespace drawinglayer::primitive2d
{
/** ShadowPrimitive2D class

            This primitive defines a generic shadow geometry construction
            for 2D objects. It decomposes to a TransformPrimitive2D embedded
            into a ModifiedColorPrimitive2D.

            It's for primitive usage convenience, so that not everyone has
            to implement the generic shadow construction by himself.

            The same geometry as sequence of primitives is used as geometry and
            as shadow. Since these are RefCounted Uno-Api objects, no extra objects
            are needed for the shadow itself; all the local decompositions of the
            original geometry can be reused from the renderer for shadow visualisation.
        */
class DRAWINGLAYER_DLLPUBLIC ShadowPrimitive2D final : public BufferedDecompositionGroupPrimitive2D
{
private:
    /// the shadow transformation, normally just an offset
    basegfx::B2DHomMatrix maShadowTransform;

    /// the shadow color to which all geometry is to be forced
    basegfx::BColor maShadowColor;

    /// the blur radius of the shadow
    double mfShadowBlur;

    /// last used DiscreteBlurRadius and ClippedRange
    double mfLastDiscreteBlurRadius;
    basegfx::B2DRange maLastClippedRange;

    /// helpers
    void getFullyEmbeddedShadowPrimitives(Primitive2DContainer& rContainer) const;
    bool prepareValuesAndcheckValidity(basegfx::B2DRange& rRange, basegfx::B2DRange& rClippedRange,
                                       basegfx::B2DVector& rDiscreteSize,
                                       double& rfDiscreteBlurRadius,
                                       const geometry::ViewInformation2D& rViewInformation) const;

protected:
    /** method which is to be used to implement the local decomposition of a 2D primitive. */
    virtual void
    create2DDecomposition(Primitive2DContainer& rContainer,
                          const geometry::ViewInformation2D& rViewInformation) const override;

public:
    /// constructor
    ShadowPrimitive2D(basegfx::B2DHomMatrix aShadowTransform, const basegfx::BColor& rShadowColor,
                      double fShadowBlur, Primitive2DContainer&& aChildren);

    /// data read access
    const basegfx::B2DHomMatrix& getShadowTransform() const { return maShadowTransform; }
    const basegfx::BColor& getShadowColor() const { return maShadowColor; }
    double getShadowBlur() const { return mfShadowBlur; }

    /// compare operator
    virtual bool operator==(const BasePrimitive2D& rPrimitive) const override;

    /// get range
    virtual basegfx::B2DRange
    getB2DRange(const geometry::ViewInformation2D& rViewInformation) const override;

    ///  create decomposition
    virtual void
    get2DDecomposition(Primitive2DDecompositionVisitor& rVisitor,
                       const geometry::ViewInformation2D& rViewInformation) const override;

    /// provide unique ID
    virtual sal_uInt32 getPrimitive2DID() const override;
};
} // end of namespace drawinglayer::primitive2d

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