/****************************************************************************
 * 
 *					   RealNetworks Transform Architecture
 * 
 *  $Id: rtaexternalpluginhelper.h,v 1.4.4.1 2002/06/21 00:04:49 rbunnage Exp $
 * 
 *  Copyright (C) 1995-2001 RealNetworks, Inc. All rights reserved.
 *  
 *  http://www.real.com/devzone
 *
 *  This program contains proprietary information of RealNetworks, Inc, 
 *  and is licensed subject to restrictions on use and distribution.
 *
 *  External Plugin Helper Template class
 *
 *  This file defines a template for implementing the IRMAPlugin and
 *  IRMAPluginProperties interfaces which define an external plugin for the 
 *  RealNetworks Transform Architecture. 
 *
 */

#ifndef _rtaexternalpluginhelper_h
#define _rtaexternalpluginhelper_h

#include "rmaplugn.h"	// for IRMAPlugin
#include "rmaplgns.h"	// for IRMAPluginProperties
#include "rmapckts.h"	// for CLSID_IRMABuffer

template <class T>
class CRSExternalPluginHelper
	: public IRMAPlugin
    , public IRMAPluginProperties
{

public:
	CRSExternalPluginHelper( ) 
		: m_pContext( NULL )
		, m_lRefCount( 0 )
		, m_pAgent( NULL )
	{
	}

	~CRSExternalPluginHelper( )
	{
		PN_RELEASE( m_pContext );
		PN_RELEASE( m_pAgent );
	}

	// IRMAPlugin Interface Methods                         
	// called by plugin handler to get basic properties 
	STDMETHOD(GetPluginInfo) (THIS_ 
		  REF(BOOL)        bLoadMultiple,
		  REF(const char*) pDescription,
		  REF(const char*) pCopyright,
		  REF(const char*) pMoreInfoURL,
		  REF(UINT32)      versionNumber
		)
	{
		bLoadMultiple = FALSE;
		pDescription  = kValueDescription;
		pCopyright	  = kValueRealCopyright;
		pMoreInfoURL  = kValueGenericMoreInfoURL;
		versionNumber = kDefaultPluginVersion;
		return PNR_OK;
	}

	// called once by plugin handler, and later by session manager with RSMA factory
	STDMETHOD(InitPlugin) (THIS_ IUnknown* pContext )
	{
		if ( !pContext )
		{
			return PNR_POINTER;
		}
		PN_RELEASE(m_pContext);
		m_pContext = pContext;
		m_pContext->AddRef();
		return PNR_OK;
	}

	enum EPropType
	{
		eIntType = 1,
		eStringType,
		eBufferType, 
		eEndType
	};

	struct SValueEntry
	{
		EPropType eType;
		const char* pName;
		void* pData;
		UINT32 uDataSize;
	};

	STDMETHODIMP GetProperties( REF(IRMAValues*) pOptions )
	{
		IRMACommonClassFactory  *pCCF = NULL;
		PN_RESULT res = m_pContext->QueryInterface(IID_IRMACommonClassFactory, (void **) &pCCF );
		if (SUCCEEDED(res))
			res = pCCF->CreateInstance( IID_IRMAValues, (void **) &pOptions );
		
		if (FAILED(res))
			return res;

		// Count number of components, add appropriate entries to the CLSID->function list
		SValueEntry* pEntry = s_pPluginInfo;
		if( pEntry )
		{
			while( pEntry->eType != eEndType && SUCCEEDED(res) )
			{
				if( pEntry->eType == eStringType )
				{
					res = SetStringProperty( pOptions, pCCF, pEntry->pName, (const char*) pEntry->pData );
				} 
				else if ( pEntry->eType == eIntType )
				{
					res = pOptions->SetPropertyULONG32( pEntry->pName, (ULONG32) pEntry->pData );
				}	
				else if ( pEntry->eType == eBufferType )
				{
					AddBufferProperty( pCCF, pOptions, pEntry->pName, (const unsigned char*) pEntry->pData, pEntry->uDataSize );
				}
				pEntry++;
			}
		}
		PN_RELEASE( pCCF ); 
		return res;
	}
	
	// IUnknown Interface Methods                         
    STDMETHOD(QueryInterface)		(THIS_ REFIID riid, void** ppvObj)
	{
		if (IsEqualIID(riid, IID_IUnknown))
		{
			AddRef();
			*ppvObj = (IUnknown*) (IRMAPlugin*) this;
			return PNR_OK;
		}
		else if (IsEqualIID(riid, IID_IRMAPlugin))
		{
			AddRef();
			*ppvObj = (IRMAPlugin*) this;
			return PNR_OK;
		}
		else if (IsEqualIID(riid, IID_IRMAPluginProperties))
		{
			AddRef();
			*ppvObj = (IRMAPluginProperties*) this;
			return PNR_OK;
		}
		else if ( IsEqualIID(riid, IID_IRTAConfigurationAgent) 
					|| IsEqualIID(riid, IID_IRTAConnectionAgent) 
							|| IsEqualIID(riid, IID_IRTAFilter) )
		{
			if (!m_pAgent)
			{
				m_pAgent = new T();
				if (m_pAgent)
					m_pAgent->AddRef();
			}
			return m_pAgent->QueryInterface( riid, ppvObj );
		}
		else if (m_pAgent)
		{
			return m_pAgent->QueryInterface( riid, ppvObj );
		}
		*ppvObj = NULL;
		return PNR_NOINTERFACE;
	}
    
	STDMETHOD_(ULONG32,AddRef)		(THIS)
	{
		return InterlockedIncrement(&m_lRefCount);
	}
    
	STDMETHOD_(ULONG32,Release)		(THIS)
	{
		if (InterlockedDecrement(&m_lRefCount) > 0)
		{
			return m_lRefCount;
		}	
		delete this;
		return 0;
	}

protected:
	
	// override for plugin properties
	STDMETHOD(OnGetProperties) ( THIS_ REF(IRMAValues*) pIRMAValuesProperties ) { return PNR_FAIL; }


	// helper for GetProperties
	PN_RESULT SetStringProperty( IRMAValues* pOptions, IRMACommonClassFactory* pFactory, 
		const char* sName, const char* sValue)
	{
		IRMABuffer* pVal = NULL;
		PN_RESULT res = pFactory->CreateInstance( IID_IRMABuffer, (void **) &pVal );

		if (SUCCEEDED(res))
			res = pVal->Set((UCHAR *) sValue, strlen(sValue) +1 );	

		if (SUCCEEDED(res))
			res = pOptions->SetPropertyCString( sName, pVal );

		pVal->Release();
		return res;
	}
	
	void AddBufferProperty( IRMACommonClassFactory* pCCF, IRMAValues* pValues, 
		const char* pName, const unsigned char* pValue, UINT32 dataLen )
	{
		IUnknown* pIUnk = NULL;
		if( SUCCEEDED( pCCF->CreateInstance( CLSID_IRMABuffer, (void**) &pIUnk ) ) )
		{
			IRMABuffer* pBuffer = NULL;
			pIUnk->QueryInterface( IID_IRMABuffer, (void**) &pBuffer );

			// NOTE:  We have to do this here, because the Set fails if the ref count is above 1
			PN_RELEASE( pIUnk );

			pBuffer->Set( (const unsigned char *) pValue, dataLen );
			pValues->SetPropertyBuffer( pName, pBuffer );

			PN_RELEASE( pBuffer );
		}
	}

	IUnknown*				m_pContext;					// context for accessing factory

private:    
	static SValueEntry		s_pPluginInfo[];
	LONG32					m_lRefCount;				// QI count
	T*						m_pAgent;
};


#endif // _rtaexternalpluginhelper_h