Source/WebCore/page/InteractionRegion.h

/*
 * Copyright (C) 2022 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#pragma once

#include "ElementIdentifier.h"
#include "FloatRect.h"
#include "Region.h"

namespace IPC {
class Decoder;
class Encoder;
}

namespace WTF {
class TextStream;
}

namespace WebCore {

class Element;
class Page;
class RenderObject;

struct InteractionRegion {
    ElementIdentifier elementIdentifier;
    Region regionInLayerCoordinates;
    bool hasLightBackground { false };
    float borderRadius { 0 };

    WEBCORE_EXPORT ~InteractionRegion();

    template<class Encoder> void encode(Encoder&) const;
    template<class Decoder> static std::optional<InteractionRegion> decode(Decoder&);
};

inline bool operator==(const InteractionRegion& a, const InteractionRegion& b)
{
    return a.elementIdentifier == b.elementIdentifier
        && a.regionInLayerCoordinates == b.regionInLayerCoordinates
        && a.hasLightBackground == b.hasLightBackground
        && a.borderRadius == b.borderRadius;
}

WEBCORE_EXPORT std::optional<InteractionRegion> interactionRegionForRenderedRegion(RenderObject&, const Region&);

WTF::TextStream& operator<<(WTF::TextStream&, const InteractionRegion&);

template<class Encoder>
void InteractionRegion::encode(Encoder& encoder) const
{
    encoder << elementIdentifier;
    encoder << regionInLayerCoordinates;
    encoder << hasLightBackground;
    encoder << borderRadius;
}

template<class Decoder>
std::optional<InteractionRegion> InteractionRegion::decode(Decoder& decoder)
{
    std::optional<ElementIdentifier> elementIdentifier;
    decoder >> elementIdentifier;
    if (!elementIdentifier)
        return std::nullopt;

    std::optional<Region> regionInLayerCoordinates;
    decoder >> regionInLayerCoordinates;
    if (!regionInLayerCoordinates)
        return std::nullopt;
    
    std::optional<bool> hasLightBackground;
    decoder >> hasLightBackground;
    if (!hasLightBackground)
        return std::nullopt;
    
    std::optional<float> borderRadius;
    decoder >> borderRadius;
    if (!borderRadius)
        return std::nullopt;

    return { {
        WTFMove(*elementIdentifier),
        WTFMove(*regionInLayerCoordinates),
        WTFMove(*hasLightBackground),
        WTFMove(*borderRadius)
    } };
}

}