/******************************************************************************
	libx42.net - skinned vertex animation library (.NET API)
	Copyright (C) 2007 HermitWorks Entertainment Corporation

	This program is free software; you can redistribute it and/or modify it
	under the terms of the GNU General Public License as published by the Free
	Software Foundation; either version 2 of the License, or (at your option)
	any later version.

	This program is distributed in the hope that it will be useful, but
	WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
	or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
	for more details.

	You should have received a copy of the GNU General Public License along
	with this program; if not, write to the
	
		Free Software Foundation, Inc.
		51 Franklin Street, Fifth Floor
		Boston, MA  02110-1301, USA.
******************************************************************************/

#include "StdAfx.h"
#include "StreamAdapter.h"

namespace Libx42
{

using namespace System;
using namespace System::Runtime::InteropServices;

static size_t X42_CALL Stream_imp_read_fn( void *buffer, size_t cb, void *baton )
{
	try
	{
		GCHandle gch = GCHandle::FromIntPtr( IntPtr( baton ) );
		StreamAdapter ^stm = (StreamAdapter^)gch.Target;

		array< Byte > ^buf = stm->GetBuffer( (uint)cb );
		int cr = stm->BaseStream->Read( buf, 0, (int)cb );

		pin_ptr< Byte > pinBuf= &buf[0];
		memcpy( buffer, pinBuf, cr );

		return cr;
	}
	catch( ... )
	{
		return 0;
	}
}

static size_t X42_CALL Stream_imp_write_fn( const void *buffer, size_t cb, void *baton )
{
	try
	{
		GCHandle gch = GCHandle::FromIntPtr( IntPtr( baton ) );
		StreamAdapter ^stm = (StreamAdapter^)gch.Target;

		array< Byte > ^buf = stm->GetBuffer( (uint)cb );
		
		pin_ptr< Byte > pinBuf= &buf[0];
		memcpy( pinBuf, buffer, cb );
		pinBuf = nullptr;

		stm->BaseStream->Write( buf, 0, (int)cb );

		return cb;
	}
	catch( ... )
	{
		return 0;
	}
}

StreamAdapter::StreamAdapter( System::IO::Stream ^stream )
	: stm( stream )
{
	if( !stream )
		throw gcnew ArgumentNullException( "stream" );

	gch = GCHandle::Alloc( this, GCHandleType::Weak );
}

StreamAdapter::~StreamAdapter( void )
{
	StreamAdapter::!StreamAdapter();
	
	//delete stm;
	stm = nullptr;
	buf = nullptr;
}

StreamAdapter::!StreamAdapter( void )
{
	delete inStm;
	inStm = 0;

	delete outStm;
	outStm = 0;

	gch.Free();
}

x42inStream_t* StreamAdapter::InStream::get( void )
{
	if( !stm->CanRead )
		throw gcnew InvalidOperationException( "Stream is not readable." );

	if( !inStm )
	{
		inStm = new x42inStream_t;
		inStm->read_fn = Stream_imp_read_fn;
		inStm->baton = GCHandle::ToIntPtr( gch ).ToPointer();
	}

	return inStm;
}

x42outStream_t* StreamAdapter::OutStream::get( void )
{
	if( !stm->CanRead )
		throw gcnew InvalidOperationException( "Stream is not writable." );

	if( !outStm )
	{
		outStm = new x42outStream_t;
		outStm->write_fn = Stream_imp_write_fn;
		outStm->baton = GCHandle::ToIntPtr( gch ).ToPointer();
	}

	return outStm;
}

array< Byte >^ StreamAdapter::GetBuffer( uint cb )
{
	if( !buf || buf->Length < (int)cb )
		buf = gcnew array< Byte >( cb );

	return buf;
}

};