/*

 * Copyright (c) 1998-2009 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: 

 * This file contains the implementation of the UTC time ASN1 object.

 * At this moment in time this class will only deal with Zulu times and 

 * doesn't have any kind of handling for time offsets. This is not going to be 

 * a problem for certificate implementations as the PKIX (RFC2459) profile

 * defines that certificate validity periods are specified as Zulu times.

 * Points that need updating if handling for offsets are marked with __OFFSET__

 *

 */

 #include <asn1dec.h>

 EXPORT_C TASN1DecUTCTime::TASN1DecUTCTime()

 	{

 	}

 TTime TASN1DecUTCTime::GetTimeL(const TDesC8& aSource)

 	{

 	// __OFFSET__ Extract corrected time to include offset too.

 	// Did this checking ought to be done on creation rather than when we attempt to get the result?

 	// YES!

 	// I guess we ought to check that the contents we've got are long enough to contain a time!

 	if (aSource.Length()<11)

 		{

 		User::Leave(KErrArgument);

 		}

 	// Check all digits the main bit of time are valid - this doesn't check the seconds or offset

 	TInt i;

 	for (i=0;i<10;i++)

 		{

 		TUint8 j;

 		j=(TUint8)(aSource[i]-'0');

 		if (j>=10)

 			{

 			User::Leave(KErrArgument);

 			}

 		}

 	// Uh-oh, looks like we're going to have to pull each bit manually and pop it in a TDateTime thing

 	TInt Year,Month,Day,Hour,Minute,Second=0;		// Only set seconds to zero 'cos they are optional, everything else is going to be set

 	Year=(aSource[0]-'0')*10+aSource[1]-'0';

 	Year+=(Year<50)?2000:1900;						//  collection to fit with PKIX UTC/Generalised time rollover at 2049/2050

 	Month=(aSource[2]-'0')*10+aSource[3]-'0';

 	Month--;										// Because the enum for months starts at 0 not 1

 	Day=((aSource[4]-'0')*10+aSource[5]-'0') -1;//added -1 for offset from zero(!)

 	Hour=(aSource[6]-'0')*10+aSource[7]-'0';

 	Minute=(aSource[8]-'0')*10+aSource[9]-'0';

 	TInt Pos=10;

 	if (aSource.Length()>11)

 		{

 		if ((aSource[Pos]>='0')&&(aSource[Pos]<='9'))

 			{

 			// seconds

 			Second=(aSource[Pos++]-'0')*10;

 			Second += aSource[Pos++]-'0';

 			}

 		}

 	if (aSource.Length()>Pos)

 		{

 		switch (aSource[Pos])

 			{

 		case 'Z':

 			// Zulu - nothing more to do

 			break;

 		case '+':

 		case '-':

 			// __OFFSET__ Extract corrected time to include offset too.

 		    User::Leave(KErrNotSupported);

 		    break;

 		default:

 			// Error!

 			User::Leave(KErrArgument);

 			break;

 			}

 		}

 	else

 		{

 		User::Leave(KErrArgument);

 		}

 	if (Month<EJanuary || Month>EDecember)

 		{

 		User::Leave(KErrArgument);

 		}

 	TMonth month = (TMonth)Month;

 	if (	(Day<0 || Day>=Time::DaysInMonth(Year,month))	||

 			(Hour<0 || Hour>=24)	||

 			(Minute<0 || Minute>=60)	||

 			(Second<0 || Second>=60)	)

 		{

 		User::Leave(KErrArgument);

 		}

 	TDateTime D(Year,month,Day,Hour,Minute,Second,0);

 	TTime T(D);

 	return T;

 	}

 // __OFFSET__ Add GetOffset() method

 EXPORT_C TTime TASN1DecUTCTime::DecodeDERL(const TDesC8& aSource,TInt& aPos)

 	{

 	TPtrC8 Source=aSource.Mid(aPos);

 	TASN1DecGeneric gen(Source);

 	gen.InitL();

 	TTime t = GetTimeL(gen.GetContentDER());

 	aPos+=gen.LengthDER();

 	return t;

 	}

 EXPORT_C TTime TASN1DecUTCTime::DecodeDERL(const TASN1DecGeneric& aGen)

 	{

 	return GetTimeL(aGen.GetContentDER());

 	}