/*

 * Copyright 2018 Google Inc.

 *

 * Use of this source code is governed by a BSD-style license that can be

 * found in the LICENSE file.

 */

#ifndef SkSGMaskEffect_DEFINED

#define SkSGMaskEffect_DEFINED

#include "include/core/SkRect.h"

#include "include/core/SkRefCnt.h"

#include "modules/sksg/include/SkSGEffectNode.h"

#include "modules/sksg/include/SkSGRenderNode.h"

#include <cstdint>

#include <utility>

class SkCanvas;

class SkMatrix;

struct SkPoint;

namespace sksg {

class InvalidationController;

/**

 * Concrete Effect node, applying a mask to its descendants.

 *

 */

class MaskEffect final : public EffectNode {

public:

    enum class Mode : uint32_t {

        kAlphaNormal,

        kAlphaInvert,

        kLumaNormal,

        kLumaInvert,

    };

    static sk_sp<MaskEffect> Make(sk_sp<RenderNode> child, sk_sp<RenderNode> mask,

                                  Mode mode = Mode::kAlphaNormal) {

        return (child && mask)

            ? sk_sp<MaskEffect>(new MaskEffect(std::move(child), std::move(mask), mode))

            : nullptr;

    }

    ~MaskEffect() override;

protected:

    MaskEffect(sk_sp<RenderNode>, sk_sp<RenderNode> mask, Mode);

    void onRender(SkCanvas*, const RenderContext*) const override;

    const RenderNode* onNodeAt(const SkPoint&)     const override;

    SkRect onRevalidate(InvalidationController*, const SkMatrix&) override;

private:

    const sk_sp<RenderNode> fMaskNode;

    const Mode              fMaskMode;

    using INHERITED = EffectNode;

};

} // namespace sksg

#endif // SkSGMaskEffect_DEFINED