// SMTP.cpp: implementation of the CSMTP class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "SMTP.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

CSMTP::response_code CSMTP::response_table[] =
{
	// GENERIC_SUCCESS
	{ 250, _T( "SMTP服務器錯誤" ) },
	// CONNECT_SUCCESS
	{ 220, _T( "SMTP服務器不可用" ) },
	// DATA_SUCCESS
	{ 354, _T( "SMTP服務器不能接收數據" ) },
	// QUIT_SUCCESS
	{ 221, _T( "SMTP沒有中止會話" ) }
};

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CSMTP::CSMTP( LPCTSTR szSMTPServerName, UINT nPort )
{
	ASSERT( szSMTPServerName != NULL );
	AfxSocketInit();    //初始化Windows Sockets類的使用
	m_sSMTPServerHostName = szSMTPServerName;
	m_nPort = nPort;
	m_bConnected = FALSE;
	m_sError = _T( "OK" );
	response_buf = NULL;
}

CSMTP::~CSMTP()
{
	Disconnect();   //斷開連接
}

CString CSMTP::GetServerHostName()
{
	return m_sSMTPServerHostName;
}
//建立到服務器的連接
BOOL CSMTP::Connect()
{
	CString sHello;
	TCHAR local_host[ 80 ];
	if( m_bConnected )
		return TRUE;
	
	try
	{
		response_buf = new TCHAR[ RESPONSE_BUFFER_SIZE ];

		if( response_buf == NULL )
		{
			m_sError = _T( "內存不足！" );
			return FALSE;
		}
	}
	catch( CException *e )    //使用基類進行捕捉
	{      
		response_buf = NULL;
		m_sError = _T( "內存不足！" );
		delete e;
		return FALSE;
	}

	if( !m_wsSMTPServer.Create() )
	{
		m_sError = _T( "無法創建套接字！" );
		delete response_buf;
		response_buf = NULL;
		return FALSE;
	}
	if( !m_wsSMTPServer.Connect( GetServerHostName(), GetPort() ) )
	{
		m_sError = _T( "無法連接到服務器" );
		m_wsSMTPServer.Close();
		delete response_buf;
		response_buf = NULL;
		return FALSE;
	}
	if( !get_response( CONNECT_SUCCESS ) )  
	{
		m_sError = _T( "服務器沒有響應" );
		m_wsSMTPServer.Close();
		delete response_buf;
		response_buf = NULL;
		return FALSE;
	}
	gethostname( local_host, 80 );   //得到本地機器標準主機名
	sHello.Format( _T( "HELO %s\r\n" ), local_host );
	m_wsSMTPServer.Send( (LPCTSTR)sHello, sHello.GetLength() );  //建立連接后發送數據
	if( !get_response( GENERIC_SUCCESS ) )
	{
		m_wsSMTPServer.Close();
		delete response_buf;
		response_buf = NULL;
		return FALSE;
	}
	m_bConnected = TRUE;
	return TRUE;
}
//斷開連接
BOOL CSMTP::Disconnect()
{
	BOOL ret;
	if( !m_bConnected )
		return TRUE;
	CString sQuit = _T( "QUIT\r\n" );
	m_wsSMTPServer.Send( (LPCTSTR)sQuit, sQuit.GetLength() );

	ret = get_response( QUIT_SUCCESS );
	m_wsSMTPServer.Close();

	if( response_buf != NULL )
	{
		delete[] response_buf;
		response_buf = NULL;
	}

	m_bConnected = FALSE;
	return ret;
}
//取得SMTP服務器端口號
UINT CSMTP::GetPort()
{
	return m_nPort;
}
//取得錯誤信息
CString CSMTP::GetLastError()
{
	return m_sError;
}
//發郵件到服務器
BOOL CSMTP::SendMessage(CMailMessage * msg)
{
	ASSERT( msg != NULL );
	if( !m_bConnected )
	{
		m_sError = _T( "必須首先創建連接！" );
		return FALSE;
	}
	if( FormatMailMessage( msg ) == FALSE )
	{
		return FALSE;
	}
	if( transmit_message( msg ) == FALSE )
	{
		return FALSE;
	}
	return TRUE;
}
//格式化郵件信息
BOOL CSMTP::FormatMailMessage( CMailMessage* msg )
{
	ASSERT( msg != NULL );
	if( msg->GetNumRecipients() == 0 )
	{
		m_sError = _T( "No Recipients" );
		return FALSE;
	}
	msg->FormatMessage();
	return TRUE;
}
//配置服務器
void CSMTP::SetServerProperties( LPCTSTR szSMTPServerName, UINT nPort)
{
	ASSERT( szSMTPServerName != NULL );
	if( szSMTPServerName == NULL )
		return;
	m_sSMTPServerHostName = szSMTPServerName;
	m_nPort = nPort;
}

//獲得郵件體得到發送內容
CString CSMTP::cook_body(CMailMessage * msg)
{
	ASSERT( msg != NULL );
	CString sTemp;
	CString sCooked = _T( "" );
	LPTSTR szBad = _T( "\r\n.\r\n" );
	LPTSTR szGood = _T( "\r\n..\r\n" );
	int nPos;
	int nStart = 0;
	int nBadLength = strlen( szBad );
	sTemp = msg->m_sBody;
	if( sTemp.Left( 3 ) == _T( ".\r\n" ) )
		sTemp = _T( "." ) + sTemp;
	while( (nPos = sTemp.Find( szBad )) > -1 )
	{
		sCooked = sTemp.Mid( nStart, nPos );
		sCooked += szGood;
		sTemp = sCooked + sTemp.Right( sTemp.GetLength() - (nPos + nBadLength) );
	}
	return sTemp;
}
//發送郵件
BOOL CSMTP::transmit_message(CMailMessage * msg)
{
	CString sFrom;
	CString sTo;
	CString sTemp;
	CString sEmail;
    CString sSubject;

	ASSERT( msg != NULL );
	if( !m_bConnected )
	{
		m_sError = _T( "必須首先創建連接！" );
		return FALSE;
	}

	sFrom.Format( _T( "MAIL From: <%s>\r\n" ), (LPCTSTR)msg->m_sFrom );
	m_wsSMTPServer.Send( (LPCTSTR)sFrom, sFrom.GetLength() );
	if( !get_response( GENERIC_SUCCESS ) )
		return FALSE;
	
	for( int i = 0; i < msg->GetNumRecipients(); i++ )
	{
		msg->GetRecipient( sEmail, sTemp, i );
		sTo.Format( _T( "RCPT TO: <%s>\r\n" ), (LPCTSTR)sEmail );
		m_wsSMTPServer.Send( (LPCTSTR)sTo, sTo.GetLength() );
		get_response( GENERIC_SUCCESS );
	}


	sTemp = _T( "DATA\r\n" );
	m_wsSMTPServer.Send( (LPCTSTR)sTemp, sTemp.GetLength() );
	if( !get_response( DATA_SUCCESS ) )
	{
		return FALSE;
	}

	sSubject.Format( _T( "SUBJECT: <%s>\r\n" ), (LPCTSTR)msg->m_sSubject );
	m_wsSMTPServer.Send( (LPCTSTR)sSubject, sSubject.GetLength() );

//	m_wsSMTPServer.Send( (LPCTSTR)msg->m_sHeader, msg->m_sHeader.GetLength() );

	sTemp = cook_body( msg );
	m_wsSMTPServer.Send( (LPCTSTR)sTemp, sTemp.GetLength() );

	sTemp = _T( "\r\n.\r\n" );
	m_wsSMTPServer.Send( (LPCTSTR)sTemp, sTemp.GetLength() );
	if( !get_response( GENERIC_SUCCESS ) )
	{
		return FALSE;
	}
	return TRUE;
}
//得到服務器響應
BOOL CSMTP::get_response( UINT response_expected )
{
	ASSERT( response_expected >= GENERIC_SUCCESS );
	ASSERT( response_expected < LAST_RESPONSE );

	CString sResponse;
	UINT response;
	response_code* pResp;

	if( m_wsSMTPServer.Receive( response_buf, RESPONSE_BUFFER_SIZE ) == SOCKET_ERROR )
	{
		m_sError = _T( "套接字錯誤！" );
		return FALSE;
	}
	sResponse = response_buf;
	sscanf( (LPCTSTR)sResponse.Left( 3 ), _T( "%d" ), &response );
	pResp = &response_table[ response_expected ];
	if( response != pResp->nResponse )
	{
		m_sError.Format( _T( "%d:%s" ), response, (LPCTSTR)pResp->sMessage );
		return FALSE;
	}
	return TRUE;
}