#ifndef THREADSAFEQUEUE_H
#define THREADSAFEQUEUE_H
// ACC - July 10, 2002
#include <list>
#ifdef WIN32
#ifdef XBOX
#include <XTL.h>
#else
	#include <windows.h>
#endif

using namespace std;

template <class Item>
class ThreadSafeQueue {
public:
	ThreadSafeQueue();
	virtual ~ ThreadSafeQueue();

	void Add(const Item& aItem);
	Item Remove();
	bool IsEmpty();
	unsigned int NumItems();
///private:
	//not implemented
	ThreadSafeQueue(const ThreadSafeQueue& aThreadSafeQueue);
	ThreadSafeQueue& operator=( const ThreadSafeQueue& aThreadSafeQueue);

	CRITICAL_SECTION		mGuardAccess;
	list<Item>				mQueue;
};


template <class Item>
ThreadSafeQueue<Item>::ThreadSafeQueue()
{
	InitializeCriticalSection(&mGuardAccess);

}

template <class Item>
ThreadSafeQueue<Item>::~ThreadSafeQueue()
{
	EnterCriticalSection(&mGuardAccess);
	mQueue.clear();
	LeaveCriticalSection(&mGuardAccess);
	DeleteCriticalSection(&mGuardAccess);
}

template <class Item>
void ThreadSafeQueue<Item>::Add(const Item& aItem)\
{
	EnterCriticalSection(&mGuardAccess);
	mQueue.push_front(aItem);
	LeaveCriticalSection(&mGuardAccess);
}

template <class Item>
Item ThreadSafeQueue<Item>::Remove()
{
	EnterCriticalSection(&mGuardAccess);
	Item item;

	if( !mQueue.empty() )  {
		item = mQueue.back();
		mQueue.pop_back();
	}

	
	LeaveCriticalSection(&mGuardAccess);

	return item;


}

template <class Item>
bool ThreadSafeQueue<Item>::IsEmpty()
{

	EnterCriticalSection(&mGuardAccess);
	bool isempty = mQueue.empty();
	LeaveCriticalSection(&mGuardAccess);

	return isempty;
}

template <class Item>
unsigned int ThreadSafeQueue<Item>::NumItems()
{
	EnterCriticalSection(&mGuardAccess);
	unsigned int items = mQueue.size();
	LeaveCriticalSection(&mGuardAccess);

	return items;
}
#endif //WIN32

#endif //THREADSAFEQUEUE_H