// Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of "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 internal classes used to parse TInternetDate data

// 

//

/**

 @file tinternetdateparser.cpp

 @see tinternetdateparser.h

*/

#include "tinternetdateparser.h"

#include "inetprottextutils.h"

#include <e32base.h>

//constants

//

const TInt KRfc1123DateTimeLength = 29;	// Sun, 06 Nov 1994 08:49:37 GMT

const TInt KHHMMSSFormatLength=8;		// HH:MM:SS

// Long form day names, 'weekday' in RFC850

//

static const TText8* const KInternetWeekDays[] = 

	{

	_S8("Monday"),

	_S8("Tuesday"),

	_S8("Wednesday"),

	_S8("Thursday"),

	_S8("Friday"),

	_S8("Saturday"),

	_S8("Sunday")

	};

// Month names, 'month' in RFC1123 & RFC850

//

static const TText8* const KInternetMonths[] = 

	{

	_S8("Jan"),

	_S8("Feb"),

	_S8("Mar"),

	_S8("Apr"),

	_S8("May"),

	_S8("Jun"),

	_S8("Jul"),

	_S8("Aug"),

	_S8("Sep"),

	_S8("Oct"),

	_S8("Nov"),

	_S8("Dec")

	};

/**

	Converts from TDateTime to Internet RFC1123 Style date strings

	@since			7.0

	@param			aDateTime The date/time to be parsed

	@leave			KErrNoMemory

	@return			HBufC8* aDescriptor containing a RFC1123 style date. 

*/

HBufC8* TInternetDateParser::ConvertToRfc1123FormL(const TDateTime& aDateTime)

	{

	const TChar KSpace = ' ';

	HBufC8* dateTime = HBufC8::NewLC(KRfc1123DateTimeLength);

	TPtr8 dateTimePtr = dateTime->Des();

	// Append the wkDay

	TTime time(aDateTime);

	TInt wkDay = time.DayNoInWeek();

	TPtrC8 wkDayText(KInternetWeekDays[wkDay]);

	dateTimePtr.Append(wkDayText.Left(3));

	// Append the day number 

	_LIT8(KDayNumberFormat, ", %02d");

	TInt dayNumber = aDateTime.Day() + 1;

	dateTimePtr.AppendFormat(KDayNumberFormat, dayNumber);

	// Append month

	dateTimePtr.Append(KSpace);

	TInt month = aDateTime.Month();

	dateTimePtr.Append(TPtrC8(KInternetMonths[month]));

	// Append year

	_LIT8(KYearDigitFormat, " %4d");

	TInt year = aDateTime.Year();

	dateTimePtr.AppendFormat(KYearDigitFormat, year);

	// Append Time HH:MM:SS

	dateTimePtr.Append(KSpace);

	_LIT8(KHHMMSSFormat, "%02d:%02d:%02d GMT");

	dateTimePtr.AppendFormat(KHHMMSSFormat, aDateTime.Hour(),aDateTime.Minute(),aDateTime.Second());

	CleanupStack::Pop(dateTime);

	return dateTime;

	}

/**

	Used to parse internet text date/time into a TDateTime

	@since			7.0

	@param			aInternetTextDateTime The date/time in a text format

	@param			aDateTime The result of parsing is placed here

	@leave			KErrNoMemory, KErrCorrupt If the format of the descriptor is not valid

*/	

void TInternetDateParser::ConvertFromInternetFormL(const TDesC8& aInternetTextDateTime, TDateTime& aDateTime)

	{

	const TChar KComma = ',';

	TInt colonLoc = aInternetTextDateTime.Locate(KComma);

	switch (colonLoc)

		{

	case -1:	// ANSI C asctime() format: Sun Nov  6 08:49:37 1994

		ConvertFromAscTimeFormL(aInternetTextDateTime, aDateTime);

		break;

	case 3:		// RFC 1123 Style Date: Sun, 06 Nov 1994 08:49:37 GMT

	case 6:		// RFC 850 Style Date: Sunday, 06-Nov-94 08:49:37 GMT

	case 7:		

	case 8:	

	case 9:		

		{

		TPtrC8 dateTime(aInternetTextDateTime.Right(aInternetTextDateTime.Length() -(colonLoc+1))); // Remove "<day>,"

		ConvertFromRfc1123And850FormL(dateTime, aDateTime);	

		}

		break;

	default:

		User::Leave(KErrCorrupt);

		};

	}

/**

	@param			aRfcDateTime 

	@param			aDateTime The result of parsing is placed here

 */	

void TInternetDateParser::ConvertFromRfc1123And850FormL(const TDesC8& aRfcDateTime, TDateTime& aDateTime)

	{

	TPtrC8 dateTime(aRfcDateTime);

	InetProtTextUtils::RemoveWhiteSpace(dateTime, InetProtTextUtils::ERemoveBoth);

	TInt textLeft = ParseRfcDateDayMonthYearL(dateTime, aDateTime);

	if (textLeft <= 0)

		User::Leave(KErrCorrupt);

	dateTime.Set(dateTime.Right(textLeft));

	InetProtTextUtils::RemoveWhiteSpace(dateTime, InetProtTextUtils::ERemoveLeft);

	ParseHHMMSSTimeL(dateTime, aDateTime);

	textLeft= dateTime.Length() - KHHMMSSFormatLength;

	if (textLeft > 1) // Must still have leading space

		{

		dateTime.Set(dateTime.Right(textLeft));

		InetProtTextUtils::RemoveWhiteSpace(dateTime, InetProtTextUtils::ERemoveLeft);

		TTimeIntervalMinutes timeOffset = 0;

		ParseTimeOffsetL(dateTime, timeOffset);

		if (timeOffset.Int() > 0 || timeOffset.Int() < 0)

			{

			TTime time(aDateTime);

			time -= timeOffset;

			aDateTime = time.DateTime();

			}

		}

	else

		User::Leave(KErrCorrupt); // Must include a timezone or timeoffset

	}

/**

	@param			aTimeOffset 

	@param			aOffsetMinutes 

 */

void TInternetDateParser::ParseHHMMTimeOffsetL(const TDesC8& aTimeOffset, TTimeIntervalMinutes& aOffsetMinutes)

	{

	TInt offsetTextLength=aTimeOffset.Length();

	if (offsetTextLength != 5) // +0000 or -0000

		User::Leave(KErrCorrupt);

	TPtrC8 timeOffset(aTimeOffset.Right(offsetTextLength-1));

	TInt num=0;

	if (InetProtTextUtils::ConvertDescriptorToInt(timeOffset, num) !=4)

		User::Leave(KErrCorrupt); // not 0000

	TInt minutes = num % 100;

	TInt hours = num / 100;

	TInt offsetMinutes=0;

	if (minutes < 60 && hours < 24)

		offsetMinutes = minutes + (hours * 60);

	if (aTimeOffset[0] == '-')

		offsetMinutes *= -1;

	aOffsetMinutes = offsetMinutes;

	}

/**

	@param			aTimeOffset 

	@param			aOffsetMinutes 

 */

void TInternetDateParser::ParseTimeOffsetL(const TDesC8& aTimeOffset, TTimeIntervalMinutes& aOffsetMinutes)

	{

	TInt offsetMinutes=0;

	TInt offsetTextLength = aTimeOffset.Length();

	if (offsetTextLength > 1)

		{

		// check second letter to see if UT, GMT

		// and to differentiate between Standard and Daylight Savings

		switch (aTimeOffset[1])					

			{

		case 'M' : // GMT

		case 'T' : // UT

			{

			return;

			}

		case 'S': // Standard Time (Daylight Savings Time is one hour ahead);

			offsetMinutes -= 60;

			break;

		case 'D' : // Daylight Savings Time

			break;

		default:

			// Must be either corrupt or an explicit HHMM +/- offset

			ParseHHMMTimeOffsetL(aTimeOffset, aOffsetMinutes);

			return;

			};

		// Check first letter to find out if its Eastern, Central, Mountain or Pacific Time

		switch (aTimeOffset[0])

			{

		case 'E' : // EST or EDT -4

			offsetMinutes -=240;

			break;

		case 'C' : // CST or CDT -5

			offsetMinutes -=300;

			break;

		case 'M' : // MST or MDT -6

			offsetMinutes -= 360;

			break;

		case 'P' : // PST or PDT -7

			offsetMinutes -=420;

			break;

		default:

			// either the format is invalid or it is a non standard 3 letter timezone

			// in either case 

			return;

			};

		}

	else // This must be a military single letter format time zone

		// According to RFC2882 These Military Timezones are obsolete. Also since A can be either +1 or -1 depending on the specification

		// it should be ignored unless there is additional Out of band Information

		{

		return; // Do nothing

		}

	aOffsetMinutes = offsetMinutes;

	}

/**

	@param			aDateTimeText 

	@param			aDateTime 

 */

void TInternetDateParser::ParseHHMMSSTimeL(const TDesC8& aDateTimeText, TDateTime& aDateTime)

	{

	if (aDateTimeText.Length() < KHHMMSSFormatLength)  // Must be at least HH:MM:SS

		User::Leave(KErrCorrupt);

	TInt num=0;

	TInt consumed = InetProtTextUtils::ConvertDescriptorToInt(aDateTimeText, num);	

	if (consumed != 2 || num < 0 || num > 23)

		User::Leave(KErrCorrupt);

	TPtrC8 dateTime(aDateTimeText.Right(aDateTimeText.Length() -3)); // Remove HH:

	aDateTime.SetHour(num);

	consumed = InetProtTextUtils::ConvertDescriptorToInt(dateTime, num);

	if (consumed != 2 || num < 0 || num > 59)

		User::Leave(KErrCorrupt);

	dateTime.Set(dateTime.Right(dateTime.Length() -3)); // Remove MM:

	aDateTime.SetMinute(num);

	consumed = InetProtTextUtils::ConvertDescriptorToInt(dateTime, num);

	if (consumed != 2 || num < 0 || num > 59)

		User::Leave(KErrCorrupt);

	aDateTime.SetSecond(num);

	}

/**

	@param			aDateTimeText 

	@param			aDateTime 

	@return

 */

TInt TInternetDateParser::ParseRfcDateDayMonthYearL(const TDesC8& aDateTimeText, TDateTime& aDateTime)

	{

	// Parse RFC 1123 and RFC 850 style date month year parts

	// 06 Nov 1994	(RFC 1123)

	// 06-Nov-94	(RFC 850) In this case if YY < 50 then treat as 20YY otherwise 19YY

	TInt day =0;

	TInt consumed = InetProtTextUtils::ConvertDescriptorToInt(aDateTimeText,day);

	if ((consumed !=1 && consumed != 2) || aDateTimeText.Length() <= 2)

		User::Leave(KErrCorrupt);

	--day; // Symbian OS month days start from 0

	// Skip over DD and separator

	TPtrC8 dateTimeText(aDateTimeText.Right(aDateTimeText.Length()-(consumed+1)));

	TMonth month = GetMonthL(dateTimeText);

	// Skip over MMM and separator

	const TInt KConsumedMonthLength = 4;

	TInt rightLength = dateTimeText.Length() - KConsumedMonthLength ;

	if( rightLength < 0)

		{

		User::Leave(KErrCorrupt);	

		}

	dateTimeText.Set(dateTimeText.Right(rightLength)); 

	// Now get year

	TInt year;

	consumed = InetProtTextUtils::ConvertDescriptorToInt(dateTimeText, year);

	if (consumed != 4 && consumed !=2)

		User::Leave(KErrCorrupt);

	// check for YY and adjust

	if (consumed == 2)

		year += year > 50 ? 1900 : 2000;

	if (aDateTime.Set(year, month, day, 0, 0, 0, 0) != KErrNone)

		User::Leave(KErrCorrupt);

	return dateTimeText.Length() - (consumed +1);

	}

/**

	@param			aMonthText 

	@return 

 */

TMonth TInternetDateParser::GetMonthL(const TDesC8& aMonthText)

	{

	if (aMonthText.Length() < 3)

		User::Leave(KErrCorrupt);

	switch (aMonthText[0])

		{

	case 'J':		// Jan, Jun, Jul

		return (aMonthText[1] == 'a' ? EJanuary : aMonthText[2] == 'n' ? EJune : EJuly);	

	case 'F':		// Feb

		return EFebruary;

	case 'M':		// Mar, May

		return (aMonthText[2] == 'r' ? EMarch : EMay);

	case 'A':		// Apr, Aug

		return (aMonthText[1] == 'p' ? EApril : EAugust);

	case 'S':		// Sep

		return ESeptember;

	case 'O':		// Oct

		return EOctober;

	case 'N':		// Nov

		return ENovember;

	case 'D':		// Dec

		return EDecember;

	default:

		User::Leave(KErrCorrupt);

		};

	return EJanuary;

	}

/**

	@param			aAscTimeDateTime 

	@param			aDateTime

 */

void TInternetDateParser::ConvertFromAscTimeFormL(const TDesC8& aAscTimeDateTime, TDateTime& aDateTime)

	{

	// Convert a date in ascTime format ( Sun Nov  6 08:49:37 1994 )

	const TChar KSpace = ' ';

	// First remove the wkDay

	TPtrC8 dateTime(aAscTimeDateTime);

	InetProtTextUtils::RemoveWhiteSpace(dateTime, InetProtTextUtils::ERemoveBoth);

	TInt endOfWkDayLoc = dateTime.Locate(KSpace);

	if (endOfWkDayLoc != 3) // Must be following a wkDay "Sun "

		User::Leave(KErrCorrupt);

	dateTime.Set(dateTime.Right(dateTime.Length() - 3));

	InetProtTextUtils::RemoveWhiteSpace(dateTime, InetProtTextUtils::ERemoveLeft);

	// Now parse the month then skip over MMM

	TMonth month = GetMonthL(dateTime);

	dateTime.Set(dateTime.Right(dateTime.Length() - 3));

	InetProtTextUtils::RemoveWhiteSpace(dateTime, InetProtTextUtils::ERemoveLeft);

	// Now parse the monthDay

	TInt day = 0;

	TInt consumed = InetProtTextUtils::ConvertDescriptorToInt(dateTime, day);

	if (consumed < 0)

		User::Leave(KErrCorrupt);

	dateTime.Set(dateTime.Right(dateTime.Length() - consumed));

	InetProtTextUtils::RemoveWhiteSpace(dateTime, InetProtTextUtils::ERemoveLeft);

	// Now get the time

	ParseHHMMSSTimeL(dateTime, aDateTime);

	dateTime.Set(dateTime.Right(dateTime.Length() - KHHMMSSFormatLength));	

	// Now the year

	InetProtTextUtils::RemoveWhiteSpace(dateTime, InetProtTextUtils::ERemoveLeft);

	TInt year;

	consumed = InetProtTextUtils::ConvertDescriptorToInt(dateTime, year);

	if (consumed !=4)

		User::Leave(KErrCorrupt);

	if (aDateTime.Set(year, month, day-1, aDateTime.Hour(), aDateTime.Minute(), aDateTime.Second(), 0) != KErrNone)

		User::Leave(KErrCorrupt);

	}