// Copyright (c) 2004-2009 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 <tz.h>

#include "ReadOnlyTzDb.h"

#include <f32file.h>

#include "dataprovider.h"

#include <vtzrules.h>

const TUint KDefaultTzNumericId = 0;

// TZ Database is stored in the timezone server's own private area

_LIT(KTzDbFileNameRom,"Z:\\private\\1020383E\\TZDB.DBZ");

_LIT(KTzDbFileNameFlash,"C:\\private\\1020383E\\TZDB.DBZ");

_LIT(KTzDbFileNameFlashCorrupt,"C:\\private\\1020383E\\TZDB.DB~");

CReadOnlyTzDb* CReadOnlyTzDb::NewL(RFs& aFs, CTzSwiObserver& aSwiObserver, MTzDataObserver& aTzDataObserver)

	{

	CReadOnlyTzDb* self = new(ELeave) CReadOnlyTzDb(aFs, aSwiObserver, aTzDataObserver);

	CleanupStack::PushL(self);

	self->ConstructL();

	CleanupStack::Pop(self);

	return self;

	}

CReadOnlyTzDb::CReadOnlyTzDb(RFs& aFs, CTzSwiObserver& aSwiObserver, MTzDataObserver& aTzDataObserver)

	: iFs(aFs), iSwiObserver(aSwiObserver), iTzDataObserver(aTzDataObserver), iTzDbDataFromFlash(EFalse)

	{

	}

void CReadOnlyTzDb::ConstructL()

	{

	// Open the database, map the file into memory and build the entity tables

	InitialiseL();

	// Add observer to watch SWI completion

	iSwiObserver.AddObserverL(this);

	}

//

// Returns the memory address of the start of RAM copy of TZ Database file

//

TInt CReadOnlyTzDb::StartAddress() const 

	{ 

	return iStartAddress; 

	}

//

// Loads the TZ Database from given file into RAM.

//

TInt CReadOnlyTzDb::CopyDatabaseToRam(const TDesC& aTzDbFileName)

  {

	TInt error = KErrNone;

	RFile file;

	TUint fileMode = EFileShareReadersOnly | EFileRead | EFileStream;

	error = file.Open(iFs, aTzDbFileName, fileMode);

	if (error == KErrNone)

		{

		TInt size = 0;

		error = file.Size(size);

		if ( (error == KErrNone) && (size <= 0) )

			{

			error = KErrCorrupt;

			}

		if (error == KErrNone)

			{

			if (iTzDbData) 

				{

				iChunk.Close();

				iTzDbData = NULL;

				}

			error = iChunk.CreateLocal(size,size) ;

			if (error == KErrNone )

				{

				// Allocate memory inside the memory chunk

				iTzDbData = new (iChunk.Base()) TUint8 [size];

				// Set a TPtr to "point" at the created memory

				TPtr8 flashDataPtr(iTzDbData, size);

				error = file.Read(0,flashDataPtr,size);

				if (error == KErrNone)

					{

					iStartAddress = reinterpret_cast<TInt>(iTzDbData);

					}

				}

			}

		}

	file.Close();

	return error;

	}

TInt CReadOnlyTzDb::InvalidateFlashDatabaseL()

	{

	RFile file;

	CleanupClosePushL(file);	

	TUint fileMode = EFileShareExclusive | EFileWrite | EFileStream;

	TInt error = file.Open(iFs, KTzDbFileNameFlash, fileMode);

	if (error == KErrNone)

		{

		error = file.Rename(KTzDbFileNameFlashCorrupt);

		}

	CleanupStack::PopAndDestroy(&file);

	return error;

	}

void CReadOnlyTzDb::InitialiseL()

	{

	// deny access to Flash-based database 

	// if it is being restored in this precise moment

	// We must not allow access to the ROM-based DB either, 

	// because this might contain outdated data.

	if (iRestoreInProcess)

		{

		User::Leave(KErrNotReady);

		}

	//

	// try to copy TZ Database from file in Flash drive

	//

	TInt error = CopyDatabaseToRam(KTzDbFileNameFlash);

	//

	// if it wasn't found or couldn't be opened, try to copy from file in ROM

	//

	if (error != KErrNone)

		{

		User::LeaveIfError(CopyDatabaseToRam(KTzDbFileNameRom));

		iTzDbDataFromFlash = false;

		}

	else

		{

		iTzDbDataFromFlash = true;

		}

	//

	// read header and initialise table offsets

	//

	TTzHeader* header(reinterpret_cast<TTzHeader*>(iStartAddress) );

	// check that the db version is the expected

	if (header->iVersion != KTzDbVersion)

		{

		if (iTzDbData)

			{

			ReleaseData();

			if (iTzDbDataFromFlash)

			  {

				InvalidateFlashDatabaseL();

			  }

			}

		User::Leave(KErrCorrupt);

		}

	const TInt KStringsBaseAddress				= iStartAddress + header->iOffsetToStringTable;

	const TInt KRegionsBaseAddress				= iStartAddress + header->iOffsetToRegionsTable;

	const TInt KRegionalZonesBaseAddress		= iStartAddress + header->iOffsetToRegionalZonesTable;

	const TInt KZonesDataBaseAddress			= iStartAddress + header->iOffsetToZones;

	const TInt KZonesBaseAddress				= iStartAddress + header->iOffsetToZonesTable;

	const TInt KLinksBaseAddress				= iStartAddress + header->iOffsetToLinksTable;

	const TInt KStdTimeAlignmentsBaseAddress	= iStartAddress + header->iOffsetToStdTimeAlignmentsTable;

	const TInt KRuleSetsBaseAddress				= iStartAddress + header->iOffsetToRuleSetsTable;

	const TInt KRuleUsesBaseAddress				= iStartAddress + header->iOffsetToRuleUsesTable;

	const TInt KRuleDefinitionsBaseAddress		= iStartAddress + header->iOffsetToRuleDefinitionsTable;

	//

	// create tables

	//

	iStringsTable = CTzDbStringsTable::NewL(*(reinterpret_cast<TTzStringsTable*>(KStringsBaseAddress)));

	iRegionsTable = CTzDbRegionsTable::NewL(*this, *(reinterpret_cast<TTzRegionsTable*>(KRegionsBaseAddress)));

	iRegionalZonesTable = CTzDbRegionalZonesTable::NewL(*this, *(reinterpret_cast<TTzRegionalZonesTable*>(KRegionalZonesBaseAddress)));

	iZonesTable = CTzDbZonesTable::NewL(*this, *(reinterpret_cast<TTzZonesTable*>(KZonesBaseAddress)), KZonesDataBaseAddress);

	iLinksTable	= CTzDbLinksTable::NewL(*this, *(reinterpret_cast<TTzLinksTable*>(KLinksBaseAddress)));

	iStdTimeAlignmentsTable	= CTzDbStdTimeAlignmentsTable::NewL(*(reinterpret_cast<TTzStdTimeAlignmentsTable*>(KStdTimeAlignmentsBaseAddress)));

	iRuleSetsTable = CTzDbRuleSetsTable::NewL(*this, *(reinterpret_cast<TTzRuleSetsTable*>(KRuleSetsBaseAddress)));

	iRuleUsesTable = CTzDbRuleUsesTable::NewL(*(reinterpret_cast<TTzRuleUsesTable*>(KRuleUsesBaseAddress)));

	iRuleDefinitionsTable = CTzDbRuleDefinitionsTable::NewL(*(reinterpret_cast<TTzRuleDefinitionsTable*>(KRuleDefinitionsBaseAddress)));	

	}

//

// Releases all RAM used by the database

//

void CReadOnlyTzDb::ReleaseData()

	{

	// delete all entity tables that are created at startup

	delete iStringsTable;			iStringsTable = NULL;

	delete iRegionsTable;			iRegionsTable = NULL;

	delete iRegionalZonesTable;		iRegionalZonesTable = NULL;

	delete iZonesTable;				iZonesTable = NULL;

	delete iLinksTable;				iLinksTable = NULL;

	delete iStdTimeAlignmentsTable;	iStdTimeAlignmentsTable = NULL;

	delete iRuleSetsTable;			iRuleSetsTable = NULL;

	delete iRuleUsesTable;			iRuleUsesTable = NULL;

	delete iRuleDefinitionsTable;	iRuleDefinitionsTable = NULL;

	iStartAddress = 0;

	iChunk.Close(); iTzDbData = NULL;

	}

CReadOnlyTzDb::~CReadOnlyTzDb()

	{

	iSwiObserver.RemoveObserver(this);

	ReleaseData();

	}

//

// Returns the CTzId object that corresponds to the location set as default in the database

//

CTzId* CReadOnlyTzDb::GetDefaultTimeZoneIdL()

	{

	if (iZonesTable == NULL)

		{

		InitialiseL();

		}

	CTzId* defTZID = NULL;

	CTzDbZone* defZone = GetZoneL((reinterpret_cast<TTzHeader*>(iStartAddress))->iOffsetToDefaultZone);

	if (defZone)

		{

		CleanupStack::PushL(defZone); // push #1

		HBufC8* fullZoneName = defZone->GetFullZoneNameLC(); // push #2

		defTZID = CTzId::NewL(defZone->LocationId());

		CleanupStack::PushL(defTZID); // push #3

		defTZID->SetIdL(*fullZoneName);

		CleanupStack::Pop(defTZID);

		CleanupStack::PopAndDestroy(2, defZone);

		}

	return defTZID;

	}

void CReadOnlyTzDb::GetTzRulesL(CTzRules& aTzRules, CTzId& aTzId)

	{

	if (iZonesTable == NULL)

		{

		InitialiseL();

		}

	TRAPD(err, DoGetTzRulesL(aTzRules, aTzId));

	if ( (err == KErrCorrupt) && (iTzDbData) )

		{

		ReleaseData();

		// if the corruption occurred while accessing the Flash DB, we must flag it 

		// as corrupt before propagating the leave

		if (iTzDbDataFromFlash)

		  {

			InvalidateFlashDatabaseL();

			}

		}

	User::LeaveIfError(err);

	}

void CReadOnlyTzDb::DoGetTzRulesL(CTzRules& aTzRules, CTzId& aTzId)

	{

	CTzDbZone* zone = FindZoneL(aTzId,ETrue);

	if (zone)

		{

		CleanupStack::PushL(zone);

		zone->GetRulesL(aTzRules);

		CleanupStack::PopAndDestroy(zone);

		}

	}

TBool CReadOnlyTzDb::IsIdInDbL(TUint aTzId)

	{

	if (iZonesTable == NULL)

		{

		InitialiseL();

		}

	CTzDbZone* zone = FindZoneByNumericIdL(aTzId);

	TBool ret = (zone)?ETrue:EFalse;

	delete zone;

	return ret;

	}

//

// Returns the CTzDbZone object corresponding to the location received (as CTzId)

// The supplied CTzId has two different IDs: a numeric one and a name (string ID).

// If the numeric ID is set (>0), it is used to perform the database search. Otherwise,

// the name is used to do the search.

//

// If aFillInLocationIDs is ETrue, it also fills in the unset zone ID in the supplied CTzId

//

CTzDbZone* CReadOnlyTzDb::FindZoneL(CTzId& aLocation, TBool aFillInLocationIDs)

	{

	CTzDbZone* zone = NULL;

	if (aLocation.TimeZoneNumericID() > KDefaultTzNumericId)

		{

		zone = FindZoneByNumericIdL(aLocation.TimeZoneNumericID());

		if (zone && aFillInLocationIDs)

			{

			CleanupStack::PushL(zone); // push #1

			HBufC8* fullZoneName = zone->GetFullZoneNameLC(); // push #2

			aLocation.SetIdL(*fullZoneName);

			CleanupStack::PopAndDestroy(fullZoneName); // pop #2

			CleanupStack::Pop(zone); // pop #1

			}

		}

	else

		{

		zone = FindZoneByNameL(aLocation.TimeZoneNameID());

		if (zone)

			{

			CleanupStack::PushL(zone); // push #1

			aLocation.SetId(zone->LocationId());

			CleanupStack::Pop(zone); // pop #1

			}

		}

	return zone;

	}

//

//

// Looks for a Zone database entity given a location name

// Returns the Zone as a CTzDbZone* (NULL if it can't find

// a Zone in the database that matches the received location)

//

CTzDbZone* CReadOnlyTzDb::FindZoneByNameL(const TDesC8& aLocation)

	{

	// first of all, look in links table

	CTzDbZone* retZone = iLinksTable->FindZoneL(aLocation);

	if (retZone == NULL) 

		{ // received location was the name of an actual zone

		// break up Location in Region and City names: e.g. "Europe/London" = "Europe" + "London"

		TInt separatorOffset = aLocation.Locate('/');

		HBufC8* regionName;

		HBufC8* cityName;

		if (separatorOffset >= 0)

			{

			regionName = aLocation.Left(separatorOffset).AllocLC();  // push #1

			cityName = aLocation.Right(aLocation.Length() - (separatorOffset+1)).AllocLC(); // push #2

			}

		else

			{

			_LIT8(KNullStr,"");

			regionName = KNullStr().AllocLC(); // push #1

			cityName = aLocation.AllocLC(); // push #2

			}

		CTzDbRegion* region = iRegionsTable->FindRegionL(*regionName);

		if (region)

			{

			CleanupStack::PushL(region); // push #3

			retZone = region->FindZoneL(*cityName);

			CleanupStack::PopAndDestroy(region); // pop #3

			} // if (region)  

		CleanupStack::PopAndDestroy(2,regionName); // pop #2, #1 - cityName, regionName

		}

	return retZone;

	}

CTzDbZone* CReadOnlyTzDb::FindZoneByNumericIdL(TUint aLocationId)

	{

	return iZonesTable->GetZoneByIdL(aLocationId);

	}

//

//

// The following methods provide access to the entity tables

//

TPtrC8 CReadOnlyTzDb::GetStringL(TUint aOffset) const

	{

	return iStringsTable->GetStringL(aOffset);

	}

const TTzRuleDefinition& CReadOnlyTzDb::GetTRuleDefinition(TUint aOffset) const

	{

	return iRuleDefinitionsTable->GetRuleDefinition(aOffset);

	}

const TTzRegionalZoneIndex& CReadOnlyTzDb::GetTRegionalZoneIndex(TUint aReference) const

	{

	return iRegionalZonesTable->GetTRegionalZoneIndex(aReference);

	}

CTzDbZone* CReadOnlyTzDb::GetZoneL(TUint aReference) const

	{

	return iZonesTable->GetZoneL(aReference);

	}

const TTzZone& CReadOnlyTzDb::GetTZone(TUint aReference) const

	{

	return iZonesTable->GetTZone(aReference);

	}

const TTzStdTimeAlignment& CReadOnlyTzDb::GetTStdTimeAlignment(TUint aReference) const

	{

	return iStdTimeAlignmentsTable->GetTStdTimeAlignment(aReference);

	}

const TTzRuleUse& CReadOnlyTzDb::GetTRuleUse(TUint aReference) const

	{

	return iRuleUsesTable->GetTRuleUse(aReference);

	}

CTzDbRuleSet* CReadOnlyTzDb::GetRuleSetL(TUint aReference) const

	{

	return iRuleSetsTable->GetRuleSetL(aReference);

	}

//

// The following methods (inherited from MBackupRestoreNotificationObserver)

// provide BackupRestore support

void CReadOnlyTzDb::BackupBeginningL()

	{

	// No action needed

	}

void CReadOnlyTzDb::BackupCompletedL()

	{

	// No action needed

	}

void CReadOnlyTzDb::RestoreBeginningL()

	{

	// set flag indicating that restoring has begun

	SetRestoreInProcess();

	}

void CReadOnlyTzDb::RestoreCompletedL()

	{

	// reset flag

	ResetRestoreInProcess();	

	ReleaseData();	

	InitialiseL();

	}

void CReadOnlyTzDb::HandleDatabaseChangeL(RTz::TTzChanges aChange)

	{

	//notify the TZ Data Observer that a change has occurred

	iTzDataObserver.NotifyTZDataStatusChangeL(aChange);

	ReleaseData();

	InitialiseL();

	}

/*

Retrieves the UTC offset for a given numeric time zone id.

@param aTime time at which the UTC offset for given time zone is required.

@param aTzId a numeric time zone id,

@return	TInt offset from UTC (in minutes).

*/

TInt CReadOnlyTzDb::GetOffsetForTimeZoneIdL(const TTime& aTime, TInt aTzId)

	{

	if (iZonesTable == NULL)

		{

		InitialiseL();

		}

	TInt offset = 0;

	TDateTime nowDate(aTime.DateTime() );

	CTzDbZone* zone = FindZoneByNumericIdL(aTzId);;

	CTzDbStdTimeAlignment* timeAlignment;

	if (zone != NULL)

		{

		//

		// zone has been found

		//			

		CleanupStack::PushL(zone);

		timeAlignment = zone->FindStdTimeAlignmentL

			(

			nowDate.Year(),

			nowDate.Month(),

			nowDate.Day(),

			nowDate.Hour(),

			nowDate.Minute(),

			ETzUtcTimeReference

			);

		if(timeAlignment)

			{

			offset = timeAlignment->UtcOffset();

			delete timeAlignment;

			}

		CleanupStack::PopAndDestroy(zone);

		}

	return offset;

	}

//

// Called by CTzDbChangeNotifier to notify of a TZ Database change

// 

void CReadOnlyTzDb::NotifyTZDataStatusChangeL(RTz::TTzChanges aChange)

	{

	HandleDatabaseChangeL(aChange);

	}