#include "StdAfx.h"
#include "SMTPMailConnect.h"

CNEWSMTPMailConnect::CNEWSMTPMailConnect(void)
{
}

CNEWSMTPMailConnect::~CNEWSMTPMailConnect(void)
{
}

BOOL CNEWSMTPMailConnect::Connect( LPCTSTR lpszHostDomain, DWORD dwTimeout /*= 10000*/ ) throw()
{
    CSimpleArray<CString> arrSMTP;
    _GetSMTPList(lpszHostDomain, arrSMTP);
    for(int i=0; i<arrSMTP.GetSize(); i++)
    {
        if(CSMTPConnection::Connect(arrSMTP[i], dwTimeout) == TRUE)
            return TRUE;
    }
    return FALSE;
}

void CNEWSMTPMailConnect::_GetSMTPList( LPCTSTR lpszHostDomain, CSimpleArray<CString>& arrSMTP )
{
    PDNS_RECORD pRec = NULL;
    if(DnsQuery(lpszHostDomain, DNS_TYPE_MX, DNS_QUERY_STANDARD,
        NULL, &pRec, NULL) == ERROR_SUCCESS)
    {
        PDNS_RECORD pRecOrig = pRec;
        while(pRec)
        {
            if(pRec->wType == DNS_TYPE_MX)
                arrSMTP.Add(pRec->Data.MX.pNameExchange);
            pRec = pRec->pNext;
        }
        DnsRecordListFree(pRecOrig,DnsFreeRecordList);
    }
}