sky/engine/core/frame/FrameHost.h

/*
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#ifndef SKY_ENGINE_CORE_FRAME_FRAMEHOST_H_
#define SKY_ENGINE_CORE_FRAME_FRAMEHOST_H_

#include "sky/engine/platform/heap/Handle.h"
#include "sky/engine/wtf/FastAllocBase.h"
#include "sky/engine/wtf/Noncopyable.h"
#include "sky/engine/wtf/OwnPtr.h"
#include "sky/engine/wtf/PassOwnPtr.h"

namespace blink {

class Page;
class ServiceProvider;
class Settings;

// FrameHost is the set of global data shared between multiple frames
// and is provided by the embedder to each frame when created.
// FrameHost currently corresponds to the Page object in core/page
// however the concept of a Page is moving up out of Blink.
// In an out-of-process iframe world, a single Page may have
// multiple frames in different process, thus Page becomes a
// browser-level concept and Blink core/ only knows about its LocalFrame (and FrameHost).
// Separating Page from the rest of core/ through this indirection
// allows us to slowly refactor Page without breaking the rest of core.
class FrameHost final {
    WTF_MAKE_NONCOPYABLE(FrameHost); WTF_MAKE_FAST_ALLOCATED;
public:
    static PassOwnPtr<FrameHost> create(Page&, ServiceProvider*);
    static PassOwnPtr<FrameHost> createDummy(Settings*);

    ~FrameHost();

    // Careful: This function will eventually be removed.
    Page& page() const { return *m_page; }
    Settings& settings() const;

    ServiceProvider* services() const { return m_services; }

    // Corresponds to pixel density of the device where this Page is
    // being displayed. In multi-monitor setups this can vary between pages.
    // This value does not account for Page zoom, use LocalFrame::devicePixelRatio instead.
    float deviceScaleFactor() const;

private:
    FrameHost(Page&, ServiceProvider*);
    FrameHost(Settings*);

    Page* m_page;
    ServiceProvider* m_services;
    Settings* m_settings;
};

}

#endif  // SKY_ENGINE_CORE_FRAME_FRAMEHOST_H_