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 * the License. You may obtain a copy of the License at
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 *
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 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
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 * The Initial Developer of the Original Code is
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 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
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 * Contributor(s):
 *
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 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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#ifndef nsTransferable_h__
#define nsTransferable_h__

#include "nsIFormatConverter.h"
#include "nsITransferable.h"
#include "nsCOMPtr.h"
#include "nsString.h"
#include "nsTArray.h"

class nsString;
class nsDataObj;

//
// DataStruct
//
// Holds a flavor (a mime type) that describes the data and the associated data.
//
struct DataStruct
{
  DataStruct ( const char* aFlavor )
    : mDataLen(0), mFlavor(aFlavor), mCacheFileName(nsnull) { }
  ~DataStruct();
  
  const nsCString& GetFlavor() const { return mFlavor; }
  void SetData( nsISupports* inData, PRUint32 inDataLen );
  void GetData( nsISupports** outData, PRUint32 *outDataLen );
  nsIFile * GetFileSpec(const char * aFileName);
  bool IsDataAvailable() const { return (mData && mDataLen > 0) || (!mData && mCacheFileName); }
  
protected:

  enum {
    // The size of data over which we write the data to disk rather than
    // keep it around in memory.
    kLargeDatasetSize = 1000000        // 1 million bytes
  };
  
  nsresult WriteCache(nsISupports* aData, PRUint32 aDataLen );
  nsresult ReadCache(nsISupports** aData, PRUint32* aDataLen );
  
  nsCOMPtr<nsISupports> mData;   // OWNER - some varient of primitive wrapper
  PRUint32 mDataLen;
  const nsCString mFlavor;
  char *   mCacheFileName;

};

/**
 * XP Transferable wrapper
 */

class nsTransferable : public nsITransferable
{
public:

  nsTransferable();
  virtual ~nsTransferable();

    // nsISupports
  NS_DECL_ISUPPORTS
  NS_DECL_NSITRANSFERABLE

protected:

    // get flavors w/out converter
  nsresult GetTransferDataFlavors(nsISupportsArray** aDataFlavorList);
 
  nsTArray<DataStruct> mDataArray;
  nsCOMPtr<nsIFormatConverter> mFormatConv;

};

#endif // nsTransferable_h__
