// Copyright (c) 2006-2009 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:

// SqlSrvStatementCollation.cpp

// 

//

#include "SqlSrvCollation.h"

#include "SqlPanic.h"

#include "SqlUtil.h"

#include "sqlite3.h"

#include "SqliteSymbian.h"		//sqlite3SymbianLastOsError()

///////////////////////////////////////////////////////////////////////////////////////////////////////////////

/////////////////////////////        Local const data   ///////////////////////////////////////////////////////

///////////////////////////////////////////////////////////////////////////////////////////////////////////////

//4 collated comparisons + 1 folded comparison

const TInt KCollationMethodCount = 4 + 1;

//Names of the user defined collations (zero-terminated 16-bit strings)

const TUint16* KCollationMethodName[KCollationMethodCount] = 

	{

	(const TUint16*)L"CompareC0", 

	(const TUint16*)L"CompareC1", 

	(const TUint16*)L"CompareC2", 

	(const TUint16*)L"CompareC3", 

	(const TUint16*)L"CompareF"

	};

///////////////////////////////////////////////////////////////////////////////////////////////////////////////

/////////////////////////////        Local functions      /////////////////////////////////////////////////////

///////////////////////////////////////////////////////////////////////////////////////////////////////////////

//User-defined collation function prototype, accepted by SQLITE

typedef TInt (*TCollationMethodPtr)(void* aUserDefinedData, TInt aByteSize1, const void* aPtr1, TInt aByteSize2, const void* aPtr2);

/**

This function is used for collated/folded string comparisons,

{aByteSize1, aPtr1} - string 1, UTF16 encoded. aByteSize1 - length in bytes.

{aByteSize2, aPtr2} - string 2, UTF16 encoded. aByteSize2 - length in bytes.

aLevel - 0,1,2,3 - collation level; -1 - folded string comparison;

The function returns negative, zero or positive if the first string is less than, equal to, or 

greater than the second string.

@internalComponent

*/

static TInt Compare(TInt aLevel, TInt aByteSize1, const void* aPtr1, TInt aByteSize2, const void* aPtr2)

	{

	TPtrC16 ptr1(static_cast <const TUint16*> (aPtr1), (TUint)aByteSize1 /sizeof(TUint16));

	TPtrC16 ptr2(static_cast <const TUint16*> (aPtr2), (TUint)aByteSize2 /sizeof(TUint16));

	return aLevel >= 0 ? ptr1.CompareC(ptr2, aLevel, NULL) : ptr1.CompareF(ptr2);

	}

/**

User defined function which will be used by SQLITE engine for collated string comparisons,

collation level 0.

{aByteSize1, aPtr1} - string 1, UTF16 encoded. aByteSize1 - length in bytes.

{aByteSize2, aPtr2} - string 2, UTF16 encoded. aByteSize2 - length in bytes.

The function returns negative, zero or positive if the first string is less than, equal to, or 

greater than the second string.

@internalComponent

*/

static TInt CompareC0(void*, TInt aByteSize1, const void* aPtr1, TInt aByteSize2, const void* aPtr2)

	{

	return Compare(0, aByteSize1, aPtr1, aByteSize2, aPtr2);

	}

/**

User defined function which will be used by SQLITE engine for collated string comparisons,

collation level 1.

{aByteSize1, aPtr1} - string 1, UTF16 encoded. aByteSize1 - length in bytes.

{aByteSize2, aPtr2} - string 2, UTF16 encoded. aByteSize2 - length in bytes.

The function returns negative, zero or positive if the first string is less than, equal to, or 

greater than the second string.

@internalComponent

*/

static TInt CompareC1(void*, TInt aByteSize1, const void* aPtr1, TInt aByteSize2, const void* aPtr2)

	{

	return Compare(1, aByteSize1, aPtr1, aByteSize2, aPtr2);

	}

/**

User defined function which will be used by SQLITE engine for collated string comparisons,

collation level 2.

{aByteSize1, aPtr1} - string 1, UTF16 encoded. aByteSize1 - length in bytes.

{aByteSize2, aPtr2} - string 2, UTF16 encoded. aByteSize2 - length in bytes.

The function returns negative, zero or positive if the first string is less than, equal to, or 

greater than the second string.

@internalComponent

*/

static TInt CompareC2(void*, TInt aByteSize1, const void* aPtr1, TInt aByteSize2, const void* aPtr2)

	{

	return Compare(2, aByteSize1, aPtr1, aByteSize2, aPtr2);

	}

/**

User defined function which will be used by SQLITE engine for collated string comparisons,

collation level 3.

{aByteSize1, aPtr1} - string 1, UTF16 encoded. aByteSize1 - length in bytes.

{aByteSize2, aPtr2} - string 2, UTF16 encoded. aByteSize2 - length in bytes.

The function returns negative, zero or positive if the first string is less than, equal to, or 

greater than the second string.

@internalComponent

*/

static TInt CompareC3(void*, TInt aByteSize1, const void* aPtr1, TInt aByteSize2, const void* aPtr2)

	{

	return Compare(3, aByteSize1, aPtr1, aByteSize2, aPtr2);

	}

/**

User defined function which will be used by SQLITE engine for folded string comparisons,

{aByteSize1, aPtr1} - string 1, UTF16 encoded. aByteSize1 - length in bytes.

{aByteSize2, aPtr2} - string 2, UTF16 encoded. aByteSize2 - length in bytes.

The function returns negative, zero or positive if the first string is less than, equal to, or 

greater than the second string.

@internalComponent

*/

static TInt CompareF(void*, TInt aByteSize1, const void* aPtr1, TInt aByteSize2, const void* aPtr2)

	{

	return Compare(-1, aByteSize1, aPtr1, aByteSize2, aPtr2);

	}

//KCollationMethodPtr array contains function pointers to all user-defined collation functions

const TCollationMethodPtr KCollationMethodPtr[KCollationMethodCount] = 

	{

	&CompareC0, &CompareC1, &CompareC2, &CompareC3, &CompareF

	};

///////////////////////////////////////////////////////////////////////////////////////////////////////////////

/////////////////////////////        TSqlCollationUtil class definition      //////////////////////////////////

///////////////////////////////////////////////////////////////////////////////////////////////////////////////

/**

Initializes TSqlCollationUtil data members.

@panic SqlDb 4 In _DEBUG mode. aDbHandle is NULL.

*/

TSqlCollationUtil::TSqlCollationUtil(sqlite3* aDbHandle) :

	iDbHandle(aDbHandle)

	{

	__SQLASSERT(iDbHandle != NULL, ESqlPanicBadArgument);

	}

/**

Installs user defined collations.

At the moment 5 user defined collations with the following names are installed:

- CompareC0 - 16-bit strings collated comaprison at level 0;

- CompareC1 - 16-bit strings collated comaprison at level 1;

- CompareC2 - 16-bit strings collated comaprison at level 2;

- CompareC3 - 16-bit strings collated comaprison at level 3;

- CompareF  - 16-bit strings folded comaprison;

These user defined collations can be used in the following cases:

- as column constraint in "CREATE TABLE" SQL statements. For example:

@code

  CREATE TABLE A(Col1 TEXT COLLATE CompareC1)

@endcode

In this case every time when Col1 values have to be compared, the SQL server will use CompareC1 collation.

- as column constraint in "CREATE INDEX" SQL statements. For example:

@code

  CREATE INDEX I ON A(Col1 COLLATE CompareC2)

@endcode

In this case SQL server will use CompareC2 collation to compare Col1 values when using the index.

- In "ORDER BY" clause of "SELECT" SQL statements. For example:

@code

  SELECT * FROM A ORDER BY Col1 COLLATE CompareC3

@endcode

In this case SQL server will use CompareC3 collation to compare Col1 values when building the result set.

@leave The function may leave with some database specific errors categorised as ESqlDbError.

@panic SqlDb 2 In _DEBUG mode. iDbHandle is NULL.

*/

void TSqlCollationUtil::InstallCollationsL()

	{

	__SQLASSERT(iDbHandle != NULL, ESqlPanicInvalidObj);

	(void)sqlite3SymbianLastOsError();//clear last OS error

	//Register user defined collations

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

		{

		TInt err = sqlite3_create_collation16(iDbHandle, reinterpret_cast <const char*> (KCollationMethodName[i]), 

											  SQLITE_UTF16 | SQLITE_UTF16_ALIGNED, 0, KCollationMethodPtr[i]);

		__SQLLEAVE_IF_ERROR(::Sql2OsErrCode(err, sqlite3SymbianLastOsError()));

		}

	}

/**

@return User-defined collation methods count.

@see TSqlCollationUtil::CollationName() 

*/

TInt TSqlCollationUtil::CollationCount() const

	{

	return KCollationMethodCount;

	}

/**

@return The name of the collation method, identified by aIndex.

@panic SqlDb 4 In _DEBUG mode. aIndex >= CollationMethodCount().

@see TSqlCollationUtil::CollationsCount() 

*/

TPtrC TSqlCollationUtil::CollationName(TInt aIndex) const

	{

	__SQLASSERT((TUint)aIndex < KCollationMethodCount, ESqlPanicBadArgument);

	return TPtrC(KCollationMethodName[aIndex]);

	}