/**************************************************************
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * 
 *************************************************************/


#ifndef _DTRANSHELPER_HXX_
#define _DTRANSHELPER_HXX_

//------------------------------------------------------------------------
// includes
//------------------------------------------------------------------------

#if defined _MSC_VER
#pragma warning(push,1)
#endif
#include <windows.h>
#if defined _MSC_VER
#pragma warning(pop)
#endif
#include "..\misc\WinClip.hxx"

//------------------------------------------------------------------------
// defines
//------------------------------------------------------------------------

#define AUTO_INIT                 TRUE
#define NO_AUTO_INIT              FALSE
#define MEM_DESTROY_ON_RELEASE    TRUE
#define NO_MEM_DESTROY_ON_RELEASE FALSE

//------------------------------------------------------------------------
// deklarations
//------------------------------------------------------------------------


//-------------------------------------------------------------------------
// a helper class to manage a global memory area, the clients can write
// into the global memory area and extract the handle to the global mem
// note: not thread-safe
//-------------------------------------------------------------------------

class CStgTransferHelper
{
public:
	// will be thrown in case of failures
	class CStgTransferException
	{
	public:
		HRESULT m_hr;
		CStgTransferException( HRESULT hr ) : m_hr( hr ) {};
	};

public:
	CStgTransferHelper( 
		sal_Bool bAutoInit = sal_False, 
		HGLOBAL  hGlob = NULL, 
		sal_Bool bDelStgOnRelease = sal_False );

	~CStgTransferHelper( );

	void SAL_CALL write( const void* lpData, ULONG cb, ULONG* cbWritten = NULL );
	void SAL_CALL read( LPVOID pv, ULONG cb, ULONG* pcbRead = NULL );

	HGLOBAL SAL_CALL getHGlobal( ) const;
	void    SAL_CALL getIStream( LPSTREAM* ppStream );

	void SAL_CALL init( 
		SIZE_T newSize, 
		sal_uInt32 uiFlags = GHND, 
		sal_Bool bDelStgOnRelease = sal_False );

	void SAL_CALL init( 
		HGLOBAL hGlob, 
		sal_Bool bDelStgOnRelease = sal_False );

	// returns the size of the managed memory
	sal_uInt32 SAL_CALL memSize( CLIPFORMAT cf = CF_INVALID ) const;
	
	// free the global memory and necessary 
	// release the internal stream pointer
	void SAL_CALL cleanup( );

private:
	LPSTREAM m_lpStream;
	sal_Bool m_bDelStgOnRelease;	

private:
	CStgTransferHelper( const CStgTransferHelper& );
	CStgTransferHelper& operator=( const CStgTransferHelper& );
};

//-------------------------------------------------------------------------
// something like an auto-pointer - allows access to the memory belonging
// to a HGLOBAL and automatically unlocks a global memory at destruction 
// time
//-------------------------------------------------------------------------

class CRawHGlobalPtr
{
public:

	//---------------------------------------------
	// ctor
	//---------------------------------------------

	CRawHGlobalPtr( HGLOBAL hGlob ) :
		m_hGlob( hGlob ),
		m_bIsLocked( FALSE ),
		m_pGlobMem( NULL )
	{
	}
	

	//---------------------------------------------
	// ctor
	//---------------------------------------------

	CRawHGlobalPtr( const CStgTransferHelper& theHGlobalHelper ) :
		m_hGlob( theHGlobalHelper.getHGlobal( ) ),
		m_bIsLocked( FALSE ),
		m_pGlobMem( NULL )
	{
	}

	//---------------------------------------------
	// dtor
	//---------------------------------------------

	~CRawHGlobalPtr( )
	{
		if ( m_bIsLocked )
			GlobalUnlock( m_hGlob );
	}

	//---------------------------------------------
	// lock the global memory (initializes a 
	// pointer to this memory)
	//---------------------------------------------

	BOOL Lock( )
	{
		if ( !m_bIsLocked && ( NULL != m_hGlob ) )
		{
			m_pGlobMem = GlobalLock( m_hGlob );
			m_bIsLocked = ( NULL != m_pGlobMem );
		}

		return m_bIsLocked;
	}

	//---------------------------------------------
	// unlock the global memory (invalidates the
	// pointer to this memory)
	//---------------------------------------------

	BOOL Unlock( )
	{
		GlobalUnlock( m_hGlob );
		m_bIsLocked = FALSE;
		m_pGlobMem = NULL;
		
		return ( NO_ERROR == GetLastError( ) );
	}

	//---------------------------------------------
	// locks the global memory and returns a 
	// pointer to this memory
	//---------------------------------------------

	LPVOID GetMemPtr( )
	{		
		Lock( );
		return m_pGlobMem;
	}

	//---------------------------------------------
	// size of mem we point to
	//---------------------------------------------

	int MemSize( ) const
	{
		return GlobalSize( m_hGlob );
	}

private:
	HGLOBAL m_hGlob;
	BOOL    m_bIsLocked;
	LPVOID  m_pGlobMem;
};

#endif