/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
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 * 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.
 * 3. Neither the name of Google Inc. nor the names of its contributors
 *    may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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 */

#ifndef CustomElementObserver_h
#define CustomElementObserver_h

#include "wtf/HashMap.h"

namespace WebCore {

class Element;

class CustomElementObserver {
public:
    CustomElementObserver() { }
    virtual ~CustomElementObserver() { }

    // API for CustomElement to kick off notifications

    static void notifyElementDidFinishParsingChildren(Element*);
    static void notifyElementWasDestroyed(Element*);

protected:
    void observe(Element*);
    void unobserve(Element*);

    virtual void elementDidFinishParsingChildren(Element*) = 0;
    virtual void elementWasDestroyed(Element* element) { unobserve(element); }

private:
    // Maps elements to the observer watching them. At most one per
    // element at a time.
    typedef HashMap<Element*, CustomElementObserver*> ElementObserverMap;
    static ElementObserverMap& elementObservers();
};

}

#endif // CustomElementObserver_h