// Copyright (c) 2005-2009 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:

//

#include <s32buf.h>

#include <vtzrules.h>

#include <tz.h>

#include "tzrules.h"

const TInt KDaysInTheWeek = 7;

const TInt KTzRulesGranularity = 4;

//

// TVTzRule

//

/**

Constructor for a time zone rule.

@publishedAll

@released

@param aFrom The first date at which the rule applies.

@param aTo The last date at which the rule applies.

@param aOldOffset The UTC offset in minutes which applies before the DST change.

@param aNewOffset The UTC offset in minutes which applies after the DST change.

@param aMonth The month in which the DST change occurs.

@param aDayRule The rule defining on which day the DST change takes place.

@param aDayOfMonth The number of the day within the month, offset from zero.  Used in conjunction with 

       aDayRule to define the day when DST changes.

@param aDayOfWeek The number of the day within the week, the numerical equivalent of a TDay value.  

       Used in conjunction with aDayRule to define the day where DST changes.

@param aTimeReference Defines whether aTimeOfChange is a local (wall-clock) time or a UTC time.

@param aTimeOfChange The time of the DST change in minutes from midnight.

*/

EXPORT_C TTzRule::TTzRule(TTimeWithReference aFrom, TTimeWithReference aTo, TInt16 aOldOffset, TInt16 aNewOffset, TMonth aMonth, TTzRuleDay aDayRule,

				TUint8 aDayOfMonth, TUint8 aDayOfWeek, TTzTimeReference aTimeReference, TUint16 aTimeOfChange) :

 	iFrom(aFrom),

	iTo(aTo),

	iOldLocalTimeOffset(aOldOffset),

	iNewLocalTimeOffset(aNewOffset),

	iMonth(aMonth),

	iDayRule(aDayRule),

	iDayOfMonth(aDayOfMonth),

	iDayOfWeek(aDayOfWeek),

	iTimeReference(aTimeReference),

	iTimeOfChange(aTimeOfChange)

	{

	}

/**

Constructor for a time zone rule.

@publishedAll

@released

@param aFromYear The first year in which the rule applies.

@param aToYear The last year in which the rule applies.

@param aOldOffset The UTC offset in minutes which applies before the DST change.

@param aNewOffset The UTC offset in minutes which applies after the DST change.

@param aMonth The month in which the DST change occurs.

@param aDayRule The rule defining on which day the DST change takes place.

@param aDayOfMonth The number of the day within the month, offset from zero.  Used in conjunction with 

       aDayRule to define the day where DST changes.  

@param aDayOfWeek The number of the day within the week, the numerical equivalent of a TDay value.  

       Used in conjunction with aDayRule to define the day where DST changes.

@param aTimeReference Defines whether aTimeOfChange is a local (wall-clock) time or a UTC time.

@param aTimeOfChange The time of the DST change in minutes from midnight.

*/

EXPORT_C TTzRule::TTzRule(TInt16 aFromYear, TInt16 aToYear, TInt16 aOldOffset, TInt16 aNewOffset, TMonth aMonth, TTzRuleDay aDayRule,

				TUint8 aDayOfMonth, TUint8 aDayOfWeek, TTzTimeReference aTimeReference, TUint16 aTimeOfChange) :

 	iFrom(TTimeWithReference(TDateTime(aFromYear,EJanuary,0,0,0,0,0))),

	iTo(TTimeWithReference(TDateTime(aToYear,EDecember,30,23,59,59,0))),

	iOldLocalTimeOffset(aOldOffset),

	iNewLocalTimeOffset(aNewOffset),

	iMonth(aMonth),

	iDayRule(aDayRule),

	iDayOfMonth(aDayOfMonth),

	iDayOfWeek(aDayOfWeek),

	iTimeReference(aTimeReference),

	iTimeOfChange(aTimeOfChange)

	{

	}

/**

Default constructor for a time zone rule.

All member variables are set to zero values.

@publishedAll

@released

*/

EXPORT_C TTzRule::TTzRule() :

	iOldLocalTimeOffset(0),

	iNewLocalTimeOffset(0),

	iMonth(EJanuary),

	iDayRule(ETzFixedDate),

	iDayOfMonth(0),

	iDayOfWeek(0),

	iTimeReference(ETzWallTimeReference),

	iTimeOfChange(0)

	{

	}

/**

Copy constructor for a time zone rule.

@publishedAll

@released

*/

EXPORT_C TTzRule::TTzRule(const TTzRule& aRule) :

 	iFrom(aRule.iFrom),

	iTo(aRule.iTo),

	iOldLocalTimeOffset(aRule.iOldLocalTimeOffset),

	iNewLocalTimeOffset(aRule.iNewLocalTimeOffset),

	iMonth(aRule.iMonth),

	iDayRule(aRule.iDayRule),

	iDayOfMonth(aRule.iDayOfMonth),

	iDayOfWeek(aRule.iDayOfWeek),

	iTimeReference(aRule.iTimeReference),

	iTimeOfChange(aRule.iTimeOfChange)

	{

	}

/** 

Externalises a time zone rule to a write stream.

@param aStream Stream to which the object should be externalised. 

@internalComponent

@released

*/ 

void TTzRule::ExternalizeL(RWriteStream& aStream) const

	{

	aStream << iFrom.iTime.Int64();

	aStream << static_cast<TInt32>(iFrom.iTimeReference);

	aStream << iTo.iTime.Int64();

	aStream << static_cast<TInt32>(iTo.iTimeReference);

	aStream << iOldLocalTimeOffset;

	aStream << iNewLocalTimeOffset;

	aStream << static_cast<TInt32>(iMonth);

	aStream << static_cast<TInt32>(iDayRule);

	aStream << iDayOfMonth;

	aStream << iDayOfWeek;

	aStream << static_cast<TInt32>(iTimeReference);

	aStream << iTimeOfChange;

	}

/** 

Internalizes a time zone rule from a read stream.

@param aStream Stream from which the object should be internalised. 

@internalComponent

@released

*/ 

void TTzRule::InternalizeL(RReadStream& aStream)

	{

	TInt64 time;

	aStream >> time;	

	iFrom.iTime = TTime(time);

	iFrom.iTimeReference = static_cast<TTzTimeReference>(aStream.ReadInt32L());

	aStream >> time;	

	iTo.iTime = TTime(time);

	iTo.iTimeReference = static_cast<TTzTimeReference>(aStream.ReadInt32L());

	aStream >> iOldLocalTimeOffset;

	aStream >> iNewLocalTimeOffset;

	iMonth = static_cast<TMonth>(aStream.ReadInt32L());

	iDayRule = static_cast<TTzRuleDay>(aStream.ReadInt32L());

	aStream >> iDayOfMonth;

	aStream >> iDayOfWeek;

	iTimeReference = static_cast<TTzTimeReference>(aStream.ReadInt32L());

	aStream >> iTimeOfChange;

	}

/** 

Check if a time zone rule is applicable during a time range.

@return ETrue if the rule applies during the supplied time range, EFalse otherwise.

@param aStart Start of time range, inclusively.  ie. For a rule to be applicable, this time

       can be equal to or earlier than the rule's end time.  This time should use the same 

       time reference used when TTzRule is constructed.

@param aEnd End of time range, exclusively.  ie. In order for a rule to be applicable, this 

       time must be later than the rule's start time.  This time should use the same 

       time reference used when TTzRule is constructed.

@internalComponent

@released

*/ 

TBool TTzRule::RuleApplies(const TTime& aStart, const TTime& aEnd) const

 	{

	// If the end of the rule is in the time range or the beginning of the rule is in the time range

	return ( (iTo.iTime >= aStart) && (iFrom.iTime < aEnd) );

 	}

/**

Resolves the date rule to the precise date and time for the given year, and

returns it in a TVTzActualisedRule

For day rules ETzDayAfterDate & ETzDayBeforeDate, the reference date entered 

is inclusive in the calculation.  ie. If the reference date fits the criteria,

the reference date will be returned.   

eg. Actualise(Friday, ETzDayAfterDate, Fri Jun 22, 2007) returns Jun 22, 2007.

Deprecated.  Use TVTzActualisedRule TTzRule::ActualiseL instead.

@return The time zone rule with the precise date and time for the given year.

@param aYear Year to actualise time rules

@publishedAll

@deprecated 

@see TVTzActualisedRule TTzRule::ActualiseL(TInt aYear) const

*/

EXPORT_C TVTzActualisedRule TTzRule::Actualise(TInt aYear) const

    {

    TVTzActualisedRule rule;

    TRAP_IGNORE(rule = ActualiseL(aYear));        

    return rule;

    }

/**

Resolves the date rule to the precise date and time for the given year, and

returns it in a TVTzActualisedRule

For day rules ETzDayAfterDate & ETzDayBeforeDate, the reference date entered 

is inclusive in the calculation.  ie. If the reference date fits the criteria,

the reference date will be returned.   

eg. Actualise(Friday, ETzDayAfterDate, Fri Jun 22, 2007) returns Jun 22, 2007.

@return The time zone rule with the precise date and time for the given year.

@param aYear Year to actualise time rules

@leave KErrCorrupt if the current day rule is not one of the defined values in TTzRuleDay

@publishedAll

@released

*/

EXPORT_C TVTzActualisedRule TTzRule::ActualiseL(TInt aYear) const

	{

	TInt dayOfMonth = iDayOfMonth;

	TInt daysDifference = 0;

	TDay dayOfWeek(EMonday);

	TDateTime actualDateTime(aYear,

						(TMonth)iMonth,

						dayOfMonth,

						(iTimeOfChange / 60),

						(iTimeOfChange % 60),

						0,

						0);

	TTime actualTime(actualDateTime);

	switch(iDayRule)

		{

		case ETzFixedDate:

			// do nothing

			break;

		case ETzDayAfterDate:

			// e.g. "Sunday after the 15th"

			// find day in week for given date

			dayOfWeek = actualTime.DayNoInWeek();

			// find difference in days to the rule date

			daysDifference = iDayOfWeek - dayOfWeek;

			// make positive difference

			if (daysDifference < 0)

				{

				daysDifference += KDaysInTheWeek;	// sunday is last day of month

				}

			// set actual day

			dayOfMonth += daysDifference;

			actualDateTime.SetDay(dayOfMonth);

			break;

		case ETzDayBeforeDate:

			// e.g. "Sunday before the 15th"

			// find day in week for given date

			dayOfWeek = actualTime.DayNoInWeek();

			// find difference in days to the rule date

			daysDifference = dayOfWeek - iDayOfWeek;

			// make positive difference

			if (daysDifference < 0)

				{

				daysDifference += KDaysInTheWeek;	// sunday is last day of month

				}

			// set actual day

			dayOfMonth -= daysDifference;

			actualDateTime.SetDay(dayOfMonth);

			break;

		case ETzDayInLastWeekOfMonth:

			// e.g. "last Sunday in the month"

			// initialise the day to the last day in the month,

			dayOfMonth = actualTime.DaysInMonth() - 1; // days offset from 0

			actualDateTime.SetDay(dayOfMonth);

			// find day in week for given date

			actualTime = actualDateTime;

			dayOfWeek = actualTime.DayNoInWeek();

			// find difference in days to the rule date

			daysDifference = dayOfWeek - iDayOfWeek;

			// make positive difference

			if (daysDifference < 0)

				{

				daysDifference += KDaysInTheWeek;	// sunday is last day of month

				}

			// set actual day

			dayOfMonth -= daysDifference;

			actualDateTime.SetDay(dayOfMonth);

			break;

		default:

			User::Leave(KErrCorrupt);  // If data is corrupt method leaves

			break;

		}

	actualTime = actualDateTime;

	TVTzActualisedRule tActRule(actualTime, 

		iNewLocalTimeOffset, 

		static_cast<TTzTimeReference>(iTimeReference));

	return tActRule;

	}

//

// CTzRules

//

/**

Creates a new time zone rules object.

@return Pointer to the time zone rules.

@publishedAll

@released

*/

EXPORT_C CTzRules* CTzRules::NewL()

	{

	CTzRules* self = new(ELeave) CTzRules();

	return self;

	}

/**

Creates a new time zone rules object.

@param aStartYear The first year in which these time zone rules apply.

@param aEndYear The last year in which these time zone rules apply.

@return Pointer to the time zone rules.

@publishedAll

@released

*/

EXPORT_C CTzRules* CTzRules::NewL(TInt aStartYear, TInt aEndYear)

	{

	CTzRules* self = new(ELeave) CTzRules(aStartYear,aEndYear);

	return self;

	}

/**

Creates a new time zone rules object from a stream.

@return Pointer to the time zone rules.

@param aStream Stream with the time zone rules to be used to create a CTzRules object.

@publishedAll

@released

*/

EXPORT_C CTzRules* CTzRules::NewL(RReadStream& aStream)

	{

	CTzRules* self = new(ELeave) CTzRules();

	CleanupStack::PushL(self);

	self->InternalizeL(aStream);

	CleanupStack::Pop(self);

	return self;

	}

CTzRules::CTzRules(TInt aStartYear, TInt aEndYear) :

	iStartYear((TInt16)aStartYear),

	iEndYear((TInt16)aEndYear),

	iRules(KTzRulesGranularity)

	{

	}

CTzRules::CTzRules() :

	iRules(KTzRulesGranularity)

	{

	}

/**

Destructor.

@publishedAll

@released

*/

EXPORT_C CTzRules::~CTzRules()

	{

	delete iActualisedRulesCache;

	iRules.Reset();

	}

/**

Get the object size when it is internalize and externalised.

@return the size of thisobject 

@internalComponent

@released

*/

EXPORT_C TInt CTzRules::SizeOfObject() const

	{

	return iRules.Count() * sizeof (TTzRule) + 4*sizeof (TInt16);

	//As to 4 size of TInt16, they are for iStartYear, iEndYear, iInitialStdTimeOffset and the count of array of TTzRule

	}

/**

Internalizes time zone rules from a read stream.

@param aStream Stream from which the object should be internalised. 

@publishedAll

@released

*/

EXPORT_C void CTzRules::InternalizeL(RReadStream& aStream)

	{

	iRules.Reset();

	// read start and end year covered by rules

	iStartYear = aStream.ReadInt16L();

	iEndYear = aStream.ReadInt16L();

	// read initial std time offset

	iInitialStdTimeOffset = aStream.ReadInt16L();

	// read number of rules

	const TInt16 KCount = aStream.ReadInt16L();

	// read rules

	TTzRule rule;

	for (TInt i = 0; i < KCount; ++i)

		{

		rule.InternalizeL(aStream);

		User::LeaveIfError(iRules.Append(rule));

		}

	// The cache has been invalidated so clear it

	delete iActualisedRulesCache;

	iActualisedRulesCache = NULL;

	}

/** 

Externalises time zone rules to a write stream.

@param aStream Stream to which the object should be externalised. 

@leave KErrArgument if the output stream size is invalid

@publishedAll

@released

*/

EXPORT_C void CTzRules::ExternalizeL(RWriteStream& aStream) const

	{

	// Ensure the size of the stream is valid.

	TInt size = aStream.Sink()->SizeL();

	const TInt KMaxSize = KMaxTInt / 2;

	if (size < 0 || size >= KMaxSize)

	    {

	    User::Leave(KErrArgument);

	    }

	// write range of years covered by rules

	aStream.WriteInt16L(iStartYear);

	aStream.WriteInt16L(iEndYear);

	// write initial std time offset

	aStream.WriteInt16L(iInitialStdTimeOffset);

	// write number of rules

	const TInt16 KCount = (TInt16)iRules.Count();

	aStream.WriteInt16L(KCount);

	// write rules

	for (TInt i = 0; i < KCount; i++)

		{

		iRules[i].ExternalizeL(aStream);

		}

	}

/**

Gets the first year in which the time zone rules apply.

@return The year.

@publishedAll

@released

*/

EXPORT_C TInt CTzRules::StartYear() const

	{

	return iStartYear;

	}

/**

Gets the last year in which the time zone rules apply.

@return The year.

@publishedAll

@released

*/

EXPORT_C TInt CTzRules::EndYear() const

	{

	return iEndYear;

	}

/**

Sets the first year in which the time zone rules apply.

@param aYear The year.

@publishedAll

@released

*/

EXPORT_C void CTzRules::SetStartYear(TInt aYear)

	{

	iStartYear = (TInt16)aYear;

	}

/**

Sets the last year in which the time zone rules apply.

@param aYear The year.