Source/core/html/track/vtt/VTTRegion.h

/*
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 * modification, are permitted provided that the following conditions are
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#ifndef VTTRegion_h
#define VTTRegion_h

#include "core/dom/ContextLifecycleObserver.h"
#include "core/html/track/TextTrack.h"
#include "platform/Timer.h"
#include "platform/geometry/FloatPoint.h"
#include "wtf/PassOwnPtr.h"
#include "wtf/RefCounted.h"

namespace WebCore {

class ExceptionState;
class HTMLDivElement;
class TextTrackCueBox;

class VTTRegion : public RefCounted<VTTRegion> {
public:
    static PassRefPtr<VTTRegion> create()
    {
        return adoptRef(new VTTRegion());
    }

    virtual ~VTTRegion();

    TextTrack* track() const { return m_track; }
    void setTrack(TextTrack*);

    const String& id() const { return m_id; }
    void setId(const String&);

    double width() const { return m_width; }
    void setWidth(double, ExceptionState&);

    long height() const { return m_heightInLines; }
    void setHeight(long, ExceptionState&);

    double regionAnchorX() const { return m_regionAnchor.x(); }
    void setRegionAnchorX(double, ExceptionState&);

    double regionAnchorY() const { return m_regionAnchor.y(); }
    void setRegionAnchorY(double, ExceptionState&);

    double viewportAnchorX() const { return m_viewportAnchor.x(); }
    void setViewportAnchorX(double, ExceptionState&);

    double viewportAnchorY() const { return m_viewportAnchor.y(); }
    void setViewportAnchorY(double, ExceptionState&);

    const AtomicString scroll() const;
    void setScroll(const AtomicString&, ExceptionState&);

    void updateParametersFromRegion(VTTRegion*);

    const String& regionSettings() const { return m_settings; }
    void setRegionSettings(const String&);

    bool isScrollingRegion() { return m_scroll; }

    PassRefPtr<HTMLDivElement> getDisplayTree(Document&);

    void appendTextTrackCueBox(PassRefPtr<TextTrackCueBox>);
    void displayLastTextTrackCueBox();
    void willRemoveTextTrackCueBox(TextTrackCueBox*);

private:
    VTTRegion();

    void prepareRegionDisplayTree();

    // The timer is needed to continue processing when cue scrolling ended.
    void startTimer();
    void stopTimer();
    void scrollTimerFired(Timer<VTTRegion>*);

    enum RegionSetting {
        None,
        Id,
        Width,
        Height,
        RegionAnchor,
        ViewportAnchor,
        Scroll
    };
    RegionSetting getSettingFromString(const String&);
    void parseSettingValue(RegionSetting, const String&);
    void parseSetting(const String&, unsigned*);

    static const AtomicString& textTrackCueContainerShadowPseudoId();
    static const AtomicString& textTrackCueContainerScrollingClass();
    static const AtomicString& textTrackRegionShadowPseudoId();

    String m_id;
    String m_settings;
    double m_width;
    unsigned m_heightInLines;
    FloatPoint m_regionAnchor;
    FloatPoint m_viewportAnchor;
    bool m_scroll;

    // The cue container is the container that is scrolled up to obtain the
    // effect of scrolling cues when this is enabled for the regions.
    RefPtr<HTMLDivElement> m_cueContainer;
    RefPtr<HTMLDivElement> m_regionDisplayTree;

    // The member variable track can be a raw pointer as it will never
    // reference a destroyed TextTrack, as this member variable
    // is cleared in the TextTrack destructor and it is generally
    // set/reset within the addRegion and removeRegion methods.
    TextTrack* m_track;

    // Keep track of the current numeric value of the css "top" property.
    double m_currentTop;

    // The timer is used to display the next cue line after the current one has
    // been displayed. It's main use is for scrolling regions and it triggers as
    // soon as the animation for rolling out one line has finished, but
    // currently it is used also for non-scrolling regions to use a single
    // code path.
    Timer<VTTRegion> m_scrollTimer;
};

} // namespace WebCore
#endif