// Copyright (c) 2009, Google Inc.
// All rights reserved.
// 
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// modification, are permitted provided that the following conditions are
// met:
// 
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * 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.
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// 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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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#ifndef WorkerContextExecutionProxy_h_
#define WorkerContextExecutionProxy_h_

#if ENABLE(WORKERS)

#include <list>
#include <wtf/HashSet.h>
#include "v8.h"
#include "v8_index.h"

namespace WebCore {

class Event;
class V8EventListener;
class WorkerContext;

class WorkerContextExecutionProxy {
 public:
  WorkerContextExecutionProxy(WorkerContext*);
  ~WorkerContextExecutionProxy();

  // Returns a local handle of the context.
  v8::Local<v8::Context> GetContext() {
    return v8::Local<v8::Context>::New(m_context);
  }

  // Returns the dom constructor function for the given node type.
  v8::Local<v8::Function> GetConstructor(V8ClassIndex::V8WrapperType t);

  // Finds or creates an event listener;
  PassRefPtr<V8EventListener> FindOrCreateEventListener(
      v8::Local<v8::Value> listener, bool is_inline, bool find_only);

  // Removes an event listener;
  void RemoveEventListener(V8EventListener* listener);

  // Track the event so that we can detach it from the JS wrapper when a worker
  // terminates. This is needed because we need to be able to dispose these
  // events and releases references to their event targets: WorkerContext.
  void TrackEvent(Event* event);

  // Evaluate a script file in the current execution environment.
  v8::Local<v8::Value> Evaluate(const String& str,
                                const String& file_name,
                                int base_line);

  // Returns WorkerContext object.
  WorkerContext* worker_context() { return m_workerContext; }

  // Returns WorkerContextExecutionProxy object of the currently executing
  // context.
  static WorkerContextExecutionProxy* retrieve();

  // Returns the JS wrapper of object.
  static v8::Handle<v8::Value> ToV8Object(V8ClassIndex::V8WrapperType type,
                                          void* imp);
  static v8::Handle<v8::Value> EventToV8Object(Event* event);
  static v8::Handle<v8::Value> EventTargetToV8Object(EventTarget* target);
  static v8::Handle<v8::Value> WorkerContextToV8Object(WorkerContext* wc);

 private:
  void InitContextIfNeeded();
  void Dispose();

  // Run an already compiled script.
  v8::Local<v8::Value> RunScript(v8::Handle<v8::Script> script);

  static v8::Local<v8::Object> InstantiateV8Object(
      V8ClassIndex::V8WrapperType desc_type,
      V8ClassIndex::V8WrapperType cptr_type,
      void* impl);

  static bool ForgetV8EventObject(Event* event);

  WorkerContext* m_workerContext;
  v8::Persistent<v8::Context> m_context;
  int m_recursion;

  typedef std::list<V8EventListener*> EventListenerList;
  EventListenerList m_listeners;

  typedef HashSet<Event*> EventSet;
  EventSet m_events;
};

} // namespace WebCore

#endif // ENABLE(WORKERS)

#endif // WorkerContextExecutionProxy_h_