1 // Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies).

     2 // All rights reserved.

     3 // This component and the accompanying materials are made available

     4 // under the terms of "Eclipse Public License v1.0"

     5 // which accompanies this distribution, and is available

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

     7 //

     8 // Initial Contributors:

     9 // Nokia Corporation - initial contribution.

    10 //

    11 // Contributors:

    12 //

    13 // Description:

    14 //

    15 

    16 #include <s32buf.h>

    17 #include <vtzrules.h>

    18 #include <tz.h>

    19 

    20 #include "tzrules.h"

    21 

    22 const TInt KDaysInTheWeek = 7;

    23 const TInt KTzRulesGranularity = 4;

    24 

    25 //

    26 // TVTzRule

    27 //

    28 

    29 /**

    30 Constructor for a time zone rule.

    31 

    32 @publishedAll

    33 @released

    34 

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

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

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

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

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

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

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

    42        aDayRule to define the day when DST changes.

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

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

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

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

    47 */

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

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

    50  	iFrom(aFrom),

    51 	iTo(aTo),

    52 	iOldLocalTimeOffset(aOldOffset),

    53 	iNewLocalTimeOffset(aNewOffset),

    54 	iMonth(aMonth),

    55 	iDayRule(aDayRule),

    56 	iDayOfMonth(aDayOfMonth),

    57 	iDayOfWeek(aDayOfWeek),

    58 	iTimeReference(aTimeReference),

    59 	iTimeOfChange(aTimeOfChange)

    60 	{

    61 	}

    62 

    63 /**

    64 Constructor for a time zone rule.

    65 

    66 @publishedAll

    67 @released

    68 

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

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

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

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

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

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

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

    76        aDayRule to define the day where DST changes.  

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

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

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

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

    81 */

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

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

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

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

    86 	iOldLocalTimeOffset(aOldOffset),

    87 	iNewLocalTimeOffset(aNewOffset),

    88 	iMonth(aMonth),

    89 	iDayRule(aDayRule),

    90 	iDayOfMonth(aDayOfMonth),

    91 	iDayOfWeek(aDayOfWeek),

    92 	iTimeReference(aTimeReference),

    93 	iTimeOfChange(aTimeOfChange)

    94 	{

    95 	}

    96 

    97 /**

    98 Default constructor for a time zone rule.

    99 

   100 All member variables are set to zero values.

   101 

   102 @publishedAll

   103 @released

   104 */

   105 EXPORT_C TTzRule::TTzRule() :

   106 	iOldLocalTimeOffset(0),

   107 	iNewLocalTimeOffset(0),

   108 	iMonth(EJanuary),

   109 	iDayRule(ETzFixedDate),

   110 	iDayOfMonth(0),

   111 	iDayOfWeek(0),

   112 	iTimeReference(ETzWallTimeReference),

   113 	iTimeOfChange(0)

   114 	{

   115 	}

   116 

   117 /**

   118 Copy constructor for a time zone rule.

   119 

   120 @publishedAll

   121 @released

   122 */

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

   124  	iFrom(aRule.iFrom),

   125 	iTo(aRule.iTo),

   126 	iOldLocalTimeOffset(aRule.iOldLocalTimeOffset),

   127 	iNewLocalTimeOffset(aRule.iNewLocalTimeOffset),

   128 	iMonth(aRule.iMonth),

   129 	iDayRule(aRule.iDayRule),

   130 	iDayOfMonth(aRule.iDayOfMonth),

   131 	iDayOfWeek(aRule.iDayOfWeek),

   132 	iTimeReference(aRule.iTimeReference),

   133 	iTimeOfChange(aRule.iTimeOfChange)

   134 	{

   135 	}

   136 

   137 /** 

   138 Externalises a time zone rule to a write stream.

   139 

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

   141 @internalComponent

   142 @released

   143 */ 

   144 void TTzRule::ExternalizeL(RWriteStream& aStream) const

   145 	{

   146 	aStream << iFrom.iTime.Int64();

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

   148 	aStream << iTo.iTime.Int64();

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

   150 	aStream << iOldLocalTimeOffset;

   151 	aStream << iNewLocalTimeOffset;

   152 	aStream << static_cast<TInt32>(iMonth);

   153 	aStream << static_cast<TInt32>(iDayRule);

   154 	aStream << iDayOfMonth;

   155 	aStream << iDayOfWeek;

   156 	aStream << static_cast<TInt32>(iTimeReference);

   157 	aStream << iTimeOfChange;

   158 	}

   159 

   160 /** 

   161 Internalizes a time zone rule from a read stream.

   162 

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

   164 @internalComponent

   165 @released

   166 */ 

   167 void TTzRule::InternalizeL(RReadStream& aStream)

   168 	{

   169 	TInt64 time;

   170 	aStream >> time;	

   171 	iFrom.iTime = TTime(time);

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

   173 	aStream >> time;	

   174 	iTo.iTime = TTime(time);

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

   176 	aStream >> iOldLocalTimeOffset;

   177 	aStream >> iNewLocalTimeOffset;

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

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

   180 	aStream >> iDayOfMonth;

   181 	aStream >> iDayOfWeek;

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

   183 	aStream >> iTimeOfChange;

   184 	}

   185 

   186 

   187 /** 

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

   189 

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

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

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

   193        time reference used when TTzRule is constructed.

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

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

   196        time reference used when TTzRule is constructed.

   197 @internalComponent

   198 @released

   199 */ 

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

   201  	{

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

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

   204  	}

   205 

   206 /**

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

   208 returns it in a TVTzActualisedRule

   209 

   210 For day rules ETzDayAfterDate & ETzDayBeforeDate, the reference date entered 

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

   212 the reference date will be returned.   

   213 

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

   215 

   216 Deprecated.  Use TVTzActualisedRule TTzRule::ActualiseL instead.

   217 

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

   219 @param aYear Year to actualise time rules

   220 @publishedAll

   221 @deprecated 

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

   223 */

   224 EXPORT_C TVTzActualisedRule TTzRule::Actualise(TInt aYear) const

   225     {

   226     TVTzActualisedRule rule;

   227     TRAP_IGNORE(rule = ActualiseL(aYear));        

   228     return rule;

   229     }

   230 

   231 /**

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

   233 returns it in a TVTzActualisedRule

   234 

   235 For day rules ETzDayAfterDate & ETzDayBeforeDate, the reference date entered 

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

   237 the reference date will be returned.   

   238 

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

   240 

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

   242 @param aYear Year to actualise time rules

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

   244 @publishedAll

   245 @released

   246 */

   247 EXPORT_C TVTzActualisedRule TTzRule::ActualiseL(TInt aYear) const

   248 	{

   249 	TInt dayOfMonth = iDayOfMonth;

   250 	TInt daysDifference = 0;

   251 	TDay dayOfWeek(EMonday);

   252 

   253 	TDateTime actualDateTime(aYear,

   254 						(TMonth)iMonth,

   255 						dayOfMonth,

   256 						(iTimeOfChange / 60),

   257 						(iTimeOfChange % 60),

   258 						0,

   259 						0);

   260 	TTime actualTime(actualDateTime);

   261 	switch(iDayRule)

   262 		{

   263 		case ETzFixedDate:

   264 			// do nothing

   265 			break;

   266 

   267 		case ETzDayAfterDate:

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

   269 

   270 			// find day in week for given date

   271 			dayOfWeek = actualTime.DayNoInWeek();

   272 

   273 			// find difference in days to the rule date

   274 			daysDifference = iDayOfWeek - dayOfWeek;

   275 			// make positive difference

   276 			if (daysDifference < 0)

   277 				{

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

   279 				}

   280 

   281 			// set actual day

   282 			dayOfMonth += daysDifference;

   283 			actualDateTime.SetDay(dayOfMonth);

   284 			break;

   285 

   286 		case ETzDayBeforeDate:

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

   288 

   289 			// find day in week for given date

   290 			dayOfWeek = actualTime.DayNoInWeek();

   291 

   292 			// find difference in days to the rule date

   293 			daysDifference = dayOfWeek - iDayOfWeek;

   294 			// make positive difference

   295 			if (daysDifference < 0)

   296 				{

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

   298 				}

   299 

   300 			// set actual day

   301 			dayOfMonth -= daysDifference;

   302 			actualDateTime.SetDay(dayOfMonth);

   303 			break;

   304 

   305 		case ETzDayInLastWeekOfMonth:

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

   307 

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

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

   310 			actualDateTime.SetDay(dayOfMonth);

   311 

   312 			// find day in week for given date

   313 			actualTime = actualDateTime;

   314 			dayOfWeek = actualTime.DayNoInWeek();

   315 

   316 			// find difference in days to the rule date

   317 			daysDifference = dayOfWeek - iDayOfWeek;

   318 			// make positive difference

   319 			if (daysDifference < 0)

   320 				{

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

   322 				}

   323 

   324 			// set actual day

   325 			dayOfMonth -= daysDifference;

   326 			actualDateTime.SetDay(dayOfMonth);

   327 			break;

   328 

   329 		default:

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

   331 			break;

   332 		}

   333 

   334 	actualTime = actualDateTime;

   335 

   336 	TVTzActualisedRule tActRule(actualTime, 

   337 		iNewLocalTimeOffset, 

   338 		static_cast<TTzTimeReference>(iTimeReference));

   339 	return tActRule;

   340 	}

   341 

   342 //

   343 // CTzRules

   344 //

   345 

   346 /**

   347 Creates a new time zone rules object.

   348 @return Pointer to the time zone rules.

   349 @publishedAll

   350 @released

   351 */

   352 EXPORT_C CTzRules* CTzRules::NewL()

   353 	{

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

   355 	return self;

   356 	}

   357 

   358 /**

   359 Creates a new time zone rules object.

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

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

   362 @return Pointer to the time zone rules.

   363 @publishedAll

   364 @released

   365 */

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

   367 	{

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

   369 	return self;

   370 	}

   371 

   372 /**

   373 Creates a new time zone rules object from a stream.

   374 @return Pointer to the time zone rules.

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

   376 @publishedAll

   377 @released

   378 */

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

   380 	{

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

   382 	CleanupStack::PushL(self);

   383 	self->InternalizeL(aStream);

   384 	CleanupStack::Pop(self);

   385 	return self;

   386 	}

   387 

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

   389 	iStartYear((TInt16)aStartYear),

   390 	iEndYear((TInt16)aEndYear),

   391 	iRules(KTzRulesGranularity)

   392 	{

   393 	}

   394 

   395 CTzRules::CTzRules() :

   396 	iRules(KTzRulesGranularity)

   397 	{

   398 	}

   399 

   400 /**

   401 Destructor.

   402 @publishedAll

   403 @released

   404 */

   405 EXPORT_C CTzRules::~CTzRules()

   406 	{

   407 	delete iActualisedRulesCache;

   408 	iRules.Reset();

   409 	}

   410 

   411 /**

   412 Get the object size when it is internalize and externalised.

   413 

   414 @return the size of thisobject 

   415 @internalComponent

   416 @released

   417 */

   418 EXPORT_C TInt CTzRules::SizeOfObject() const

   419 	{

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

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

   422 	}

   423 /**

   424 Internalizes time zone rules from a read stream.

   425 

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

   427 @publishedAll

   428 @released

   429 */

   430 EXPORT_C void CTzRules::InternalizeL(RReadStream& aStream)

   431 	{

   432 	iRules.Reset();

   433 

   434 	// read start and end year covered by rules

   435 	iStartYear = aStream.ReadInt16L();

   436 	iEndYear = aStream.ReadInt16L();

   437 

   438 	// read initial std time offset

   439 	iInitialStdTimeOffset = aStream.ReadInt16L();

   440 	

   441 	// read number of rules

   442 	const TInt16 KCount = aStream.ReadInt16L();

   443 

   444 	// read rules

   445 	TTzRule rule;

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

   447 		{

   448 		rule.InternalizeL(aStream);

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

   450 		}

   451 	

   452 	// The cache has been invalidated so clear it

   453 	delete iActualisedRulesCache;

   454 	iActualisedRulesCache = NULL;

   455 	}

   456 

   457 /** 

   458 Externalises time zone rules to a write stream.

   459 

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

   461 @leave KErrArgument if the output stream size is invalid

   462 @publishedAll

   463 @released

   464 */

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

   466 	{

   467 	// Ensure the size of the stream is valid.

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

   469 	const TInt KMaxSize = KMaxTInt / 2;

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

   471 	    {

   472 	    User::Leave(KErrArgument);

   473 	    }

   474 

   475 	// write range of years covered by rules

   476 	aStream.WriteInt16L(iStartYear);

   477 	aStream.WriteInt16L(iEndYear);

   478 	

   479 	// write initial std time offset

   480 	aStream.WriteInt16L(iInitialStdTimeOffset);

   481 	

   482 	// write number of rules

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

   484 	aStream.WriteInt16L(KCount);

   485 

   486 	// write rules

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

   488 		{

   489 		iRules[i].ExternalizeL(aStream);

   490 		}

   491 	}

   492 

   493 /**

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

   495 @return The year.

   496 @publishedAll

   497 @released

   498 */

   499 EXPORT_C TInt CTzRules::StartYear() const

   500 	{

   501 	return iStartYear;

   502 	}

   503 

   504 /**

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

   506 @return The year.

   507 @publishedAll

   508 @released

   509 */

   510 EXPORT_C TInt CTzRules::EndYear() const

   511 	{

   512 	return iEndYear;

   513 	}

   514 

   515 /**

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

   517 @param aYear The year.

   518 @publishedAll

   519 @released

   520 */

   521 EXPORT_C void CTzRules::SetStartYear(TInt aYear)

   522 	{

   523 	iStartYear = (TInt16)aYear;

   524 	}

   525 

   526 /**

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

   528 @param aYear The year.

   529 @publishedAll

   530 @released

   531 */

   532 EXPORT_C void CTzRules::SetEndYear(TInt aYear)

   533 	{

   534 	iEndYear = (TInt16)aYear;

   535 	}

   536 

   537 /**

   538 Gets the number of time zone rules (TTzRules) in this set.

   539 @return The number of rules.

   540 @publishedAll

   541 @released

   542 */

   543 EXPORT_C TInt CTzRules::Count() const

   544 	{

   545 	return iRules.Count();

   546 	}

   547 

   548 /**

   549 Gets the initial UTC offset for this set of time zone rules.

   550 @return The offset in minutes.

   551 @publishedAll

   552 @released

   553 */

   554 EXPORT_C TInt CTzRules::InitialStdTimeOffset() const

   555 	{

   556 	return iInitialStdTimeOffset;

   557 	}

   558 	

   559 /**

   560 Sets the initial UTC offset for this set of time zone rules.

   561 @param aOffset The offset in minutes.

   562 @publishedAll

   563 @released

   564 */

   565 EXPORT_C void CTzRules::SetInitialStdTimeOffset(TInt aOffset)

   566 	{

   567 	// The cache has been invalidated so clear it

   568 	delete iActualisedRulesCache;

   569 	iActualisedRulesCache = NULL;

   570 	

   571 	iInitialStdTimeOffset = aOffset;

   572 	}

   573 	

   574 /**

   575 Adds a time zone rule to this set.

   576 @param aTRule The rule to be added.

   577 @publishedAll

   578 @released

   579 */

   580 EXPORT_C void CTzRules::AddRuleL(TTzRule aTRule)

   581 	{

   582 	// the cache has been invalidated so clear it

   583 	delete iActualisedRulesCache;

   584 	iActualisedRulesCache = NULL;

   585 	

   586 	TInt result = iRules.Append(aTRule);

   587 	User::LeaveIfError(result);

   588 	}

   589 

   590 /**

   591 Removes a time zone rule from this set.

   592 @param aIndex The index of the rule to be removed.

   593 @publishedAll

   594 @released

   595 */

   596 EXPORT_C void CTzRules::RemoveRule(TInt aIndex)

   597 	{

   598 	// the cache has been invalidated so clear it

   599 	delete iActualisedRulesCache;

   600 	iActualisedRulesCache = NULL;

   601 		

   602 	iRules.Remove(aIndex);

   603 	}

   604 

   605 /**

   606 Gets a time zone rule from this set.

   607 @param aIndex The index of the rule to be fetched.

   608 @return Reference to the time zone rule.

   609 @publishedAll

   610 @released

   611 */

   612 EXPORT_C TTzRule& CTzRules::operator[](TInt aIndex)

   613 	{

   614 	// prevent array bounds error

   615 	__ASSERT_ALWAYS( (aIndex < iRules.Count() && aIndex >= 0), RTz::Panic(RTz::EPanicRulesIndexOutofRange));

   616 	

   617 	return iRules[aIndex];

   618 	}

   619 

   620 /**

   621 Queries the time zone rule set to see if they apply to a specified time.

   622 @param aTime The time to be checked, using the same time reference used when constructing 

   623        CTzRules.

   624 @return ETrue if the time zone rules apply to the specified time. EFalse if not.

   625 @publishedAll

   626 @released

   627 */

   628  EXPORT_C TBool CTzRules::RulesApply(const TTime& aTime) const

   629  	{

   630 	const TTime KStart(TDateTime(iStartYear, EJanuary, 0, 0, 0, 0, 0));

   631 	const TTime KEnd(TDateTime(iEndYear + 1, EJanuary, 0, 0, 0, 0, 0));

   632 	return ((aTime >= KStart) && (aTime < KEnd));

   633  	}

   634 

   635 

   636 /**

   637 

   638 Compares two times with time references (TTzTimeReference).

   639 TTzTimeReference is either UTC, or STD, or ETzWallTimeReference.

   640 

   641 Comparison is done at some point in time when aStdOffset applies to item(s) with ETzStdTimeReference, 

   642 and aWallOffset applies to item(s) with ETzWallTimeReference.

   643 

   644 If time references for both aTimeA and aTimeB are the same, then straight comparison is done to 

   645 aTimeA and aTimeB. Otherwise, STD or wall-clock time is converted to UTC using either aStdOffset, 

   646 or aWallOffset correspondingly.

   647 

   648 Thus, aStdOffset parameter is never used if none of aTimeA and aTimeB is ETzStdTimeReference;

   649 and, similarly, aWallOffset is never used if none of aTimeA and aTimeB is ETzWallTimeReference.

   650 

   651 @param	aTimeA		- first time with reference;

   652 @param	aTimeB		- second time with reference, to compare to aTimeA;

   653 @param	aStdOffset	- an offset (in minutes) to be used for a time with ETzStdTimeReference;

   654 @param	aWallOffset	- an offset (in minutes) to be used for a time with ETzWallTimeReference;

   655 @param	aMinutesDifference	-on return, the time difference between aTimeA and aTimeB in minutes;

   656 

   657 @return TInt		-1 if aTimeA is < aTimeB;

   658 					 0 if aTimeA is equal to aTimeB;

   659 					 1 if aTimeA is > aTimeB.	 

   660 Example: 

   661 	compare 20050403T020200 local with 20050403T020100Z UTC in PST time zone (-0800):

   662 			CompareTimesWithRef(20050403T020200, wall, 20050403T020100, utc, 0(not used), -8(PST))  gives -1;

   663 	while 	CompareTimesWithRef(20050403T020200, wall, 20050403T020100, utc, 0(not used), 0(GMT))  gives 1.

   664 

   665 @internalComponent

   666 @released

   667  */ 

   668 TInt CTzRules::CompareTimesWithRef(TTime aTimeA, TTzTimeReference aTimeARef,

   669 								   TTime aTimeB, TTzTimeReference aTimeBRef,

   670 								   TInt aStdOffset, TInt aWallOffset, TTimeIntervalMinutes* aMinutesDifference) const

   671 	{

   672 	TTime timeA(aTimeA), timeB(aTimeB);

   673 	if (aTimeARef != aTimeBRef)

   674 		{

   675 		if (aTimeARef == ETzStdTimeReference)

   676 			{

   677 			timeA -= TTimeIntervalMinutes(aStdOffset);	

   678 			}

   679 		if (aTimeARef == ETzWallTimeReference)

   680 			{

   681 			timeA -= TTimeIntervalMinutes(aWallOffset);	

   682 			}

   683 		if (aTimeBRef == ETzStdTimeReference)

   684 			{

   685 			timeB -= TTimeIntervalMinutes(aStdOffset);	

   686 			}

   687 		if (aTimeBRef == ETzWallTimeReference)

   688 			{

   689 			timeB -= TTimeIntervalMinutes(aWallOffset);	

   690 			}

   691 		}

   692 

   693 	if (aMinutesDifference)

   694 		{

   695 		timeA.MinutesFrom(timeB, *aMinutesDifference);

   696 		}

   697 

   698 	return (timeA<timeB) ? -1 : ((timeA>timeB) ? 1 : 0);

   699 	}

   700 

   701 /**

   702 Based on the rules in the object calculates actualised rules for particular year and adds them

   703 to the specified array of actualised rules (CVTzActualisedRules).

   704 

   705 @param	aActRules	- an array of actualised rules where new actualised rules are added;

   706 @param	aYear		- a year for which actualised rules are added.

   707 

   708 @internalComponent

   709 @released

   710 */

   711 void CTzRules::AddActualisedRulesL(CVTzActualisedRules& aActRules, TInt aYear) const

   712    	{

   713    	const TInt count=iRules.Count();

   714    	const TTzRule* trule = NULL;

   715 

   716 	const TTime KYearBegin(TDateTime(aYear, EJanuary, 0, 0, 0, 0, 0));

   717 	const TTime KYearEnd(TDateTime(aYear + 1, EJanuary, 0, 0, 0, 0, 0));

   718 

   719    	for (TInt i = 0; i < count; i++)

   720    		{

   721    		trule = &(iRules[i]);

   722    		if ( trule->RuleApplies(KYearBegin, KYearEnd))

   723    			{

   724    			TVTzActualisedRule tactRule = trule->Actualise(aYear);

   725    

   726    			// ETzStdTimeReference is not useful for VTIMEZONE or for conversions

   727    			if(trule->iTimeReference == ETzStdTimeReference)

   728    				{

   729 				//# Time: Time for the DST switch. Important: sometimes the time is followed by a letter. The meaning of this letter is:

   730 				//no letter or w: wall clock time, actual local time.

   731 				//s: local standard time (winter time)

   732 				//u or g or z: UTC time.

   733 				//So, if a 'DST on' time is given as '0:00s', this means a switch on 0:00 local time.

   734    				//If a 'DST off' time is given as '0:00s', this means a switch on 1:00 local time (assuming a DST offset of 1 hour).

   735    				

   736    				//DST off time is always the lowest among the two.

   737 				//We do not want to use the oldlocaltimeoffset for DST Off conditions.

   738    				TInt standardOffset = trule->iOldLocalTimeOffset;

   739    				if(trule->iNewLocalTimeOffset < trule->iOldLocalTimeOffset)

   740    					{

   741    					standardOffset = trule->iNewLocalTimeOffset;

   742    					}

   743    				tactRule.iTimeOfChange -= TTimeIntervalMinutes(standardOffset);

   744    				tactRule.iTimeReference = ETzUtcTimeReference;

   745    				}

   746    				

   747   			if ( 0 >= CompareTimesWithRef(tactRule.iTimeOfChange, tactRule.iTimeReference,

   748   											trule->iTo.iTime, trule->iTo.iTimeReference,

   749   											0, trule->iOldLocalTimeOffset, NULL) )

   750   				{

   751   				// tactRule.iTimeOfChange w/ref is less or equal to trule->iTo

   752 

   753   				/*Fix for INC117764:

   754 				Before adding make sure that rule does not occur before the rules which have already been added.

   755 				For Ex-"Europe\Tirane" 

   756 				1) Rule Starts at 1/4/1984, Rule Ends at 30/6/1984, Old offset = 60, New Offset = 120 (Summer rule)

   757 				2) Rule Starts at 1/7/1984, Rule Ends at 1/7/1984, Old offset = 60, New Offset = 120 (Summer rule contd.)

   758 				3) Rule Starts at 1/9/1984, Rule Ends at 31/12/1995, Old offset = 60, New Offset = 60(winter rule) 

   759 				4) Rule Starts at 1/3/1984, Rule Ends at 31/12/9998, Old offset = 60, New Offset = 120 (Summer Rule)

   760 				The 4th rule should follow from 7/7/1984 onwards, otherwise if 4th rule is actualised for year 1984

   761 				it would look like --Rule Starts at 1/3/1984, NewOffset = 120, this will cause issues when converting time in March since summer

   762 				time won't start until April 1984.

   763 				*/

   764   				TBool ruleAdded = ETrue;

   765 				for(TInt loop = aActRules.Count()-1; loop >=0; --loop)

   766 					{

   767 					TVTzActualisedRule prevActRule = aActRules[loop];

   768 					TDateTime prevRdt = prevActRule.iTimeOfChange.DateTime();

   769 					TDateTime actRdt = tactRule.iTimeOfChange.DateTime();	

   770 					if(actRdt.Year() > prevRdt.Year())

   771 						{

   772 						//no covering rule for this year in previously added rules

   773 						//no need of looking into other year rules

   774 						break;						

   775 						}

   776 					if(actRdt.Year() == prevRdt.Year() &&

   777 					   actRdt.Month() < prevRdt.Month() &&

   778 					   tactRule.iNewOffset == prevActRule.iNewOffset)

   779 						{

   780 						//covering rule already exists so dont add this one

   781 						ruleAdded = EFalse;

   782 						break;

   783 						}	

   784 					}

   785 				if(ruleAdded)

   786 					{

   787 					aActRules.AddRuleL(tactRule);	

   788 					}

   789   				}

   790 			}

   791    		}

   792    	}

   793 

   794 /**

   795 Get actualised rules for time zone rules.

   796 @param aActRules Actualised rules for time zone rules.

   797 @publishedAll

   798 @released

   799 */

   800 EXPORT_C void CTzRules::GetActualisedRulesL(CVTzActualisedRules& aActRules) const

   801 	{

   802 	// Always add the initial offset because there may not have been

   803 	// any rules to actualise before the actualised rules range specified

   804 	TVTzActualisedRule tDefRule(TDateTime(iStartYear, EJanuary, 0, 0, 0, 0, 0), iInitialStdTimeOffset, ETzWallTimeReference);

   805 	aActRules.AddRuleL(tDefRule);

   806 	

   807 	if (iRules.Count() == 0)

   808 		{

   809 		// do nothing

   810 		}

   811 	if (iRules.Count() == 1)

   812 		{

   813 		// There is only one rule, perhaps this is an unknown timezone

   814 		// or a timezone that has never had DST, so just add that one rule

   815 		

   816 		TVTzActualisedRule tDefRule(TDateTime(aActRules.StartYear(), EJanuary, 0, 0, 0, 0, 0), iRules[0].iNewLocalTimeOffset, ETzWallTimeReference);

   817 		aActRules.AddRuleL(tDefRule);

   818 		}

   819 	else

   820 		{

   821 		// Add actualised rules for the year range spcified in aActRules

   822 		// also make sure that a year before this range is actualised

   823 		// so that the initial offset for the actualised rules range is correct

   824 		

   825 		TInt32 year(0);

   826 		for (year = aActRules.EndYear() ; year >= aActRules.StartYear() ; --year) 

   827 			{

   828 			AddActualisedRulesL(aActRules, year);

   829 			}

   830 		

   831 		// try to add an actualised rule for the previous year

   832 		// so that the start of the range will be correct

   833 		const TInt KActRulesCount(aActRules.Count());

   834 		AddActualisedRulesL(aActRules, year);

   835 		

   836 		if (aActRules.Count() == KActRulesCount)

   837 			{

   838 			// No rules were added for the year before the range being actualised

   839 			// so find the first rule that applies before this year

   840 			

   841 			TTime timeSoFar(TDateTime(iStartYear, EJanuary, 0, 0, 0, 0, 0));	

   842 			TTime endTime(TDateTime(year, EJanuary, 0, 0, 0, 0, 0));

   843 			

   844 			TBool found(EFalse);

   845 			

   846 			for (TInt i(iRules.Count() - 1) ; i >= 0 ; --i)

   847 				{

   848 				if (iRules[i].iTo.iTime > timeSoFar && iRules[i].iTo.iTime < endTime)

   849 					{

   850 					timeSoFar = iRules[i].iTo.iTime;

   851 					found = ETrue;

   852 					}

   853 				}

   854 			

   855 			if (found)

   856 				{

   857 				AddActualisedRulesL(aActRules, timeSoFar.DateTime().Year());

   858 				}

   859 			}

   860 		}

   861 	}

   862 

   863 /**

   864 Converts the received local time to UTC time.

   865 @param aTime The time to convert. On return, this contains the converted time.

   866 @publishedAll

   867 @released

   868 */ 

   869 EXPORT_C void CTzRules::ConvertToUtcL(TTime& aTime) const

   870 	{

   871 	// This check would not be necessary if we can ensure this function

   872 	// is never called with a null TTime

   873 	if (aTime == Time::NullTTime())

   874 		{

   875 		return;

   876 		}

   877 	

   878 	TInt offset = GetOffsetL(aTime, ETzWallTimeReference);

   879 	aTime -= (TTimeIntervalMinutes)(offset);	

   880 	}

   881 

   882 /**

   883 Converts the received UTC time to local time.

   884 @param aTime The time to convert. On return, this contains the converted time.

   885 @publishedAll

   886 @released

   887 */

   888 EXPORT_C void CTzRules::ConvertToLocalL(TTime& aTime) const

   889 	{

   890 	// This check would not be necessary if we can ensure this function

   891 	// is never called with a null TTime	

   892 	if (aTime == Time::NullTTime())

   893 		{

   894 		return;

   895 		}

   896 	

   897 	TInt offset = GetOffsetL(aTime, ETzUtcTimeReference);

   898 	aTime += (TTimeIntervalMinutes)(offset);	

   899 	}

   900 	

   901 /**

   902 Calculate the local time offset at the supplied time.

   903 

   904 @return local time offset

   905 @internalComponent

   906 @released

   907 */

   908 EXPORT_C TInt CTzRules::GetOffsetL(const TTime& aTime, TTzTimeReference aTimeRef) const

   909 	{

   910 	if (iActualisedRulesCache)

   911 		{

   912 		TTime startTime(TDateTime(iActualisedRulesCache->StartYear(), EJanuary, 0, 0, 0, 0, 0));	

   913 		TTime endTime(TDateTime(iActualisedRulesCache->EndYear() + 1, EJanuary, 0, 0, 0, 0, 0));

   914 		

   915 		if (aTime >= startTime && aTime <= endTime)

   916 			{

   917 			return iActualisedRulesCache->GetOffsetFromRuleL(aTime, aTimeRef);

   918 			}

   919 		}

   920 

   921 	TInt year(aTime.DateTime().Year());

   922 			

   923 	// actualise rules

   924 	delete iActualisedRulesCache;

   925 	iActualisedRulesCache = NULL;

   926 	iActualisedRulesCache = CVTzActualisedRules::NewL(year, year);

   927 	TRAPD(leaveCode,GetActualisedRulesL(*iActualisedRulesCache));

   928 	if(leaveCode != KErrNone)

   929 		{

   930 		delete iActualisedRulesCache;

   931 		iActualisedRulesCache = NULL;

   932 		User::LeaveIfError(leaveCode);		

   933 		}

   934 	

   935 	return iActualisedRulesCache->GetOffsetFromRuleL(aTime, aTimeRef);;

   936 	}

   937 

   938 /**

   939 Creates a copy of these timezone rules.

   940 

   941 @capability None

   942 @return A pointer to the CTzRules copy.

   943 @publishedAll

   944 @released

   945 */

   946 EXPORT_C CTzRules* CTzRules::CloneL() const

   947 	{

   948 	CTzRules* newRules = CTzRules::NewL();

   949 	CleanupStack::PushL(newRules);

   950 	

   951 	newRules->SetStartYear(iStartYear);

   952 	newRules->SetEndYear(iEndYear);

   953 	newRules->SetInitialStdTimeOffset(iInitialStdTimeOffset);

   954 	

   955 	TInt numRules = Count();

   956 	for (TInt i = 0; i < numRules; i++)

   957 		{

   958 		newRules->AddRuleL(iRules[i]);

   959 		}

   960 	

   961 	CleanupStack::Pop(newRules);

   962 	return newRules;

   963 	}

   964 

   965 /** Copy a time zone rule to this time zone rule.

   966 

   967 @capability None

   968 @param aTzRule A rule to copy from.

   969 @internalAll

   970 @released

   971 */

   972 EXPORT_C void CTzRules::CopyL(const CTzRules& aTzRule)

   973 	{

   974 	SetStartYear(aTzRule.iStartYear);

   975 	SetEndYear(aTzRule.iEndYear);

   976 	SetInitialStdTimeOffset(aTzRule.iInitialStdTimeOffset);

   977 	iRules.Reset();	

   978 	const TInt numRules = aTzRule.Count();

   979 	for (TInt i = 0; i < numRules; i++)

   980 		{

   981 		AddRuleL(aTzRule.iRules[i]);

   982 		}

   983 	}

   984 /**

   985 Compares two sets of timezone rules.

   986 

   987 @capability None

   988 @param aRules The timezone rules to compare with.

   989 @return ETrue if the rules are identical. EFalse if not.

   990 @publishedAll

   991 @released

   992 */

   993 EXPORT_C TBool CTzRules::IsEqualTo(const CTzRules& aRules) const

   994 	{

   995 	if (iStartYear != aRules.StartYear() ||

   996 		iEndYear != aRules.EndYear() ||

   997 		iInitialStdTimeOffset != aRules.InitialStdTimeOffset() ||

   998 		Count() != aRules.Count())

   999 		{

  1000 		return EFalse;

  1001 		}

  1002 

  1003 	const TInt KRuleCount(Count());

  1004 	for (TInt i = 0; i < KRuleCount; i++)

  1005 		{

  1006 		TTzRule rule1 = const_cast<CTzRules&>(*this)[i];

  1007 		TTzRule rule2 = const_cast<CTzRules&>(aRules)[i];

  1008 		

  1009 		if (rule1.iFrom != rule2.iFrom ||

  1010 			rule1.iTo != rule2.iTo ||

  1011 			rule1.iOldLocalTimeOffset != rule2.iOldLocalTimeOffset ||

  1012 			rule1.iNewLocalTimeOffset != rule2.iNewLocalTimeOffset ||

  1013 			rule1.iMonth != rule2.iMonth ||

  1014 			rule1.iDayRule != rule2.iDayRule ||

  1015 			rule1.iDayOfMonth != rule2.iDayOfMonth ||

  1016 			rule1.iDayOfWeek != rule2.iDayOfWeek ||

  1017 			rule1.iTimeReference != rule2.iTimeReference ||

  1018 			rule1.iTimeOfChange != rule2.iTimeOfChange )

  1019 			{

  1020 			return EFalse;

  1021 			}

  1022 		}

  1023 	return ETrue;

  1024 	}

  1025 	

  1026 /**

  1027 Converts between local (wall-clock) and UTC times.

  1028 

  1029 @return KErrNone if successful, otherwise KErrNotSupported or KErrNotFound

  1030 @param aRules The actualised rules to use.

  1031 @param aTime The time to convert, specified by aTimerRef if the time is in UTC or local time. On return, 

  1032        it will contain the converted time from UTC to local time or vice versa, depending on aTimerRef's value. 

  1033 @param aTimerRef What aTime is expressed in.

  1034 @publishedAll

  1035 @released

  1036 */

  1037 EXPORT_C TInt CTzRules::ConvertTime(CVTzActualisedRules& aRules, TTime& aTime, TTzTimeReference aTimeRef) const

  1038 	{

  1039 	TInt results = KErrNone;

  1040 	TInt offset = 0;

  1041 

  1042 #ifdef _DEBUG

  1043 	TDateTime aDateTime = aTime.DateTime();

  1044 #endif

  1045 	

  1046 	TRAP( results, offset = aRules.GetOffsetFromRuleL(aTime, aTimeRef));

  1047 	

  1048 	if (results == KErrNone)

  1049 		{

  1050 		switch (aTimeRef)

  1051 			{

  1052 			case ETzUtcTimeReference:

  1053 				aTime += TTimeIntervalMinutes(offset);

  1054 				break;

  1055 			case ETzWallTimeReference:

  1056 				aTime -= TTimeIntervalMinutes(offset);

  1057 				break;

  1058 			default:

  1059 				results = KErrNotSupported;

  1060 				break;

  1061 			}

  1062 		}

  1063 

  1064 	return (results);

  1065 	}

  1066 

  1067 //

  1068 // TVTzActualisedRule

  1069 //

  1070 

  1071 /** 

  1072 Constructor for an actualised rule (local time change).

  1073 

  1074 @param aTimeOfChange Time of local time change

  1075 @param aNewOffset New UTC offset in minutes 

  1076 @param aTimeReference Time reference

  1077 @publishedAll

  1078 @released

  1079 */

  1080 EXPORT_C TVTzActualisedRule::TVTzActualisedRule(TTime aTimeOfChange, TInt aNewOffset, TTzTimeReference aTimeReference) :

  1081 	iTimeOfChange(aTimeOfChange),

  1082 	iNewOffset(aNewOffset),

  1083 	iTimeReference(aTimeReference)

  1084 	{

  1085 	}

  1086 

  1087 

  1088 /** 

  1089 Default constructor for an actualised rule (local time change).

  1090 @publishedAll

  1091 @released

  1092 */

  1093 EXPORT_C TVTzActualisedRule::TVTzActualisedRule() :

  1094 	iTimeOfChange(0),

  1095 	iNewOffset(0),

  1096 	iTimeReference(ETzUtcTimeReference)

  1097 	{

  1098 	}

  1099 

  1100 /** 

  1101 Assignment operator for an actualised rule.

  1102 @param aRule Actualised rule

  1103 @publishedAll

  1104 @released

  1105 */

  1106 EXPORT_C void TVTzActualisedRule::operator=(TVTzActualisedRule aRule)

  1107 	{

  1108 	iTimeOfChange = aRule.iTimeOfChange;

  1109 	iNewOffset = aRule.iNewOffset;

  1110 	iTimeReference = aRule.iTimeReference;

  1111 	}

  1112 

  1113 /**

  1114 Order actualised rules by time of local time change.

  1115 @internalComponent

  1116 @released

  1117 */

  1118 TInt TVTzActualisedRule::Order(const TVTzActualisedRule& aLeft, const TVTzActualisedRule& aRight)

  1119 	{

  1120 	if (aLeft.iTimeOfChange < aRight.iTimeOfChange)

  1121 		{

  1122 		return -1;

  1123 		}

  1124 	if (aLeft.iTimeOfChange == aRight.iTimeOfChange)

  1125 		{

  1126 		return 0;

  1127 		}

  1128 	return 1;

  1129 	}

  1130 

  1131 

  1132 //

  1133 // CVTzActualisedRules

  1134 //