/*

* Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*

*/

#include "sntpclientengine.h"

#include "util.h"

// 40 second timeout on operations

#define SNTP_ENGINE_TIMEOUT 40000000 

// NTP port

#define SNTP_REMOTE_PORT 123

_LIT(KNTPEpochDate,"19000000:");

/* The simplest possible NTP request */

static const TUint8 sntpRequest[48] = {

	0x23, 0x00, 0x00, 0x00,

	0x00, 0x00, 0x00, 0x00,

	0x00, 0x00, 0x00, 0x00,

	0x00, 0x00, 0x00, 0x00,

	0x00, 0x00, 0x00, 0x00,

	0x00, 0x00, 0x00, 0x00,

	0x00, 0x00, 0x00, 0x00,

	0x00, 0x00, 0x00, 0x00,

	0x00, 0x00, 0x00, 0x00,

	0x00, 0x00, 0x00, 0x00,

	0x00, 0x00, 0x00, 0x00,

	0x00, 0x00, 0x00, 0x00 };

/* The main engine of the SNTP client */

CSNTPClient* CSNTPClient::NewL(TCommandLineArgs& aArgs)

	{

	CSNTPClient* self = CSNTPClient::NewLC(aArgs);

	CleanupStack::Pop(self);

	return self;

	}

CSNTPClient* CSNTPClient::NewLC(TCommandLineArgs& aArgs)

	{

	CSNTPClient* self = new (ELeave) CSNTPClient(aArgs);

	CleanupStack::PushL(self);

	self->ConstructL();

	return self;

	}

TSNTPClientState CSNTPClient::State()

	{

	return iState;

	}

void CSNTPClient::Start()

	{

	iState = EStateResolve;

	iResolver.GetByName(*(iArgs.iServers[iServerIndex]), iNameEntry, iStatus);

	SetActive();

	iTimer->After(SNTP_ENGINE_TIMEOUT);

	}

CSNTPClient::~CSNTPClient()

	{

	Cancel();

	iResolver.Close();

	iSock.Close();

	iSockServ.Close();

	delete iTimer;

	}

CSNTPClient::CSNTPClient(TCommandLineArgs& aArgs)

	: CActive(EPriorityStandard), iArgs(aArgs)

	{

	}

void CSNTPClient::ConstructL()

	{

	User::LeaveIfError(iSockServ.Connect());

	User::LeaveIfError(iSock.Open(iSockServ, KAfInet, KSockDatagram, KProtocolInetUdp));

	User::LeaveIfError(iResolver.Open(iSockServ, KAfInet, KProtocolInetUdp));

	iTimer = CTimeOutTimer::NewL(EPriorityHigh, *this);

	CActiveScheduler::Add(this);

	}

void CSNTPClient::RunL()

	{

	if (iStatus.Int() < 0)

		{

		User::Leave(iStatus.Int());

		}

	switch (iState)

		{

	case EStateResolve:

		iTimer->Cancel();

		iBuffer.Zero();

		iBuffer.Append(sntpRequest, 48);

		// set the port on the address

		iNameEntry().iAddr.SetPort(SNTP_REMOTE_PORT);

		iState = EStateWrite;

		iSock.SendTo(iBuffer, iNameEntry().iAddr, 0, iStatus);

		SetActive();

		iTimer->After(SNTP_ENGINE_TIMEOUT);

		break;

	case EStateWrite:

		iTimer->Cancel();

		iState = EStateRead;

		iBuffer.Zero();

		iSock.RecvFrom(iBuffer, iNameEntry().iAddr, 0, iStatus);

		SetActive();

		iTimer->After(SNTP_ENGINE_TIMEOUT);

		break;

	case EStateRead:

		{

		iTimer->Cancel();

		SetTimeL();

		iStatus = KRequestPending;

		iState = EStateComplete;

		TRequestStatus* status = &iStatus;

		SetActive();

		User::RequestComplete(status, KErrNone);

		break;

		}

	case EStateComplete:

		CActiveScheduler::Stop();

		// done

		break;

	default:

		// wuh oh. BC break!

		User::Leave(KErrArgument);

		break;

		}

	}

void CSNTPClient::DoCancel()

	{

	iTimer->Cancel();

	switch (iState)

		{

	case EStateResolve:

		iResolver.Cancel();

		break;

	case EStateWrite:

		iSock.CancelSend();

		break;

	case EStateRead:

		iSock.CancelRecv();

		break;

		}

	}

TInt CSNTPClient::RunError(TInt /* aError */)

	{

	// The current server didn't work, lets try the next if available.

	iTimer->Cancel();

	if (++iServerIndex < iArgs.iServers.Count())

		{

		Start();

		}

	else

		{

		iState = EStateFailed;

		CActiveScheduler::Stop();

		}

	return KErrNone;

	}

void CSNTPClient::TimerExpired()

	{

	Cancel();

	// The current server didn't work, lets try the next if available.

	if (++iServerIndex < iArgs.iServers.Count())

		{

		Start();

		}

	else

		{

		iState = EStateAborted;

		CActiveScheduler::Stop();

		}

	}

void CSNTPClient::SetTimeL()

	{

	TUint32 timestamp(0);

	/* Use the seconds from the transmit time field 

	   TO DO:

	      + Implement proper differential here

	 */

	for (TInt i = 40; i < 44; ++i)

		{

		timestamp = (timestamp << 8) + iBuffer[i];

		}

	// Obtain the time, including the specified timezone offset

	TTimeIntervalMinutes mins(timestamp / 60);

	TTimeIntervalSeconds secs(timestamp % 60);

	TTime ntpTime;

	User::LeaveIfError(ntpTime.Set(KNTPEpochDate));

	ntpTime += mins;

	ntpTime += secs;

	// Apply offset and (possibly) daylight savings time

	TTimeIntervalHours hours;

	if (iArgs.iApplyDaylightSavings && Util::DaylightSavingsAppliesL(ntpTime))

		{

		hours = iArgs.iOffset + 1;

		}

	else

		{

		hours = iArgs.iOffset;

		}

	ntpTime += hours;

	User::LeaveIfError(User::SetHomeTime(ntpTime));

	}

/* Timeout handler for read/write operations */

CTimeOutTimer::CTimeOutTimer(const TInt aPriority)

    : CTimer(aPriority)

    {

    }

CTimeOutTimer::~CTimeOutTimer()

    {

	Cancel();

    }

CTimeOutTimer* CTimeOutTimer::NewL(const TInt aPriority, MTimeOutNotify& aTimeOutNotify)

    {

    CTimeOutTimer *p = new (ELeave) CTimeOutTimer(aPriority);

    CleanupStack::PushL(p);

	p->ConstructL(aTimeOutNotify);

	CleanupStack::Pop();

    return p;

    }

void CTimeOutTimer::ConstructL(MTimeOutNotify &aTimeOutNotify)

    {

	iNotify=&aTimeOutNotify;

	CTimer::ConstructL();

    CActiveScheduler::Add(this);

    }

void CTimeOutTimer::RunL()

// Timer request has completed, so notify the timer's owner

    {

	iNotify->TimerExpired();

	}