// Copyright (c) 2001-2009 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:

//

#ifndef __STRINGPOOL_H__

#define __STRINGPOOL_H__ 

#include <e32base.h>

struct TStringTable;

class RStringF;

class RString;

class RStringToken;

class RStringTokenF;

class MStringPoolCloseCallBack;

class RStringBase;

class CStringPoolImplementation;

class MStringPoolCloseCallBack

/** 

Abstract callback interface that alerts implementors to when a string pool 

closes.

@publishedAll

@released

*/

	{

	//Implement this function to perform some operation when the string pool is being closed

	public:

	/** Called when the string pool is about to close. */

		virtual void StringPoolClosing()=0;

	};

/** The string pool handle object.  A string pool can have several

	distinct handles associated with it, each associated with a

	different pre-loaded table. The difference between them is that

	creating a string from an enum will interpret the enum as an

	offset into the relevant pre-loaded table */

class RStringPool

/** 

String pool handle.

A string pool can have several distinct handles associated with it, each associated 

with a different pre-loaded table. Creating a string from an enum value interprets 

the value as an offset into the relevant pre-loaded table. 

@publishedAll

@released

*/

	{

 public:

	inline RStringPool();

	IMPORT_C void OpenL();

	IMPORT_C void OpenL(const TStringTable& aTable);

	IMPORT_C void OpenL(const TStringTable& aTable,MStringPoolCloseCallBack& aCallBack);

	IMPORT_C void Close();

	IMPORT_C RStringF OpenFStringL(const TDesC8& aString) const;

	IMPORT_C RString OpenStringL(const TDesC8& aString) const;

	IMPORT_C RString String(RStringToken aString) const;

	IMPORT_C RString String(TInt aIndex,const TStringTable& aTable) const;	

	IMPORT_C RStringF StringF(RStringTokenF aString) const;

	IMPORT_C RStringF StringF(TInt aIndex,const TStringTable& aTable) const;	

 private:

	friend class RStringBase;

	friend class RString;

	friend class RStringF;

	friend class CStringPoolImplementation;

	CStringPoolImplementation* iImplementation;

	};

/** A compact (4 byte) representation of a string in the string pool. This

	class must be turned into a RStringBase (or one of its derived classes) before you can do anything

	useful with it. It is only intended to be used when storing strings 

	in situations where space matters; normaly use RStringBase.

	@see RStringBase

*/

class RStringTokenBase

/** 

Base class for the RStringToken and RStringTokenF string representations.

A compact (4 byte) representation of a string in the string pool. This

class must be turned into a RStringBase (or one of its derived classes) before you can do anything

useful with it. It is only intended to be used when storing strings 

in situations where space matters; normaly use RStringBase.

@see RStringBase

@publishedAll

@released

*/

	{

 public:

	inline RStringTokenBase();

	inline RStringTokenBase operator=(RStringBase aVal);

	inline TBool IsNull() const;

 protected:

	friend class RStringPool;

	friend class RStringBase;

	friend class RStringTokenEither;

	friend class CStringPoolImplementation;

	TUint32 iVal;

	};

class RStringToken : public RStringTokenBase

/** 

A compact (4 byte) representation of a string in the string pool. 

This class must be turned into a RString before you can do anything useful 

with it. It is only intended to be used when storing strings in situations 

where space matters. You should normally use RString. 

@publishedAll

@released

*/

	{

 public:

	inline TBool operator==(RStringToken aVal) const;

	inline TBool operator!=(RStringToken aVal) const;

	inline RStringToken operator=(RString aVal);

	friend class RStringPool;

	friend class RString;

	friend class CStringPoolImplementation;

	};

class RStringTokenF  : public RStringTokenBase

/** 

A compact (4 byte) representation of a RStringF string in the string pool. 

This class must be turned into a RStringF before you can do anything useful 

with it. It is only intended to be used when storing strings in situations 

where space matters. You should normally use RStringF. 

@publishedAll

@released

*/

	{

 public:

	inline TBool operator==(RStringTokenF aVal) const;

	inline TBool operator!=(RStringTokenF aVal) const;

	inline RStringTokenF operator=(RStringF aVal);

	friend class RStringPool;

	friend class RStringF;

	friend class CStringPoolImplementation;

	};

class RStringBase

/** 

Base class for classes that represent a string in a string pool. 

There are sub-classes for folded and non-folded strings. Use this class when 

you want to receive a string, but have no intention of comparing it with anything. 

@see RStringPool 

@publishedAll

@released

*/

	{

 public:

	inline RStringBase();

	IMPORT_C void Close();

	IMPORT_C RStringBase Copy();

	IMPORT_C const TDesC8& DesC() const;

	inline operator RStringTokenBase() const;

	IMPORT_C TInt Index(const TStringTable& aTable) const;

	IMPORT_C const TStringTable*  OriginalTableRef() const;

	inline RStringPool Pool() const;

 protected:

	friend class RStringPool;

	friend class RStringTokenBase;

	RStringPool iPool;

	TUint32 iVal;

	};

class RString : public RStringBase

/** 

A string that is stored in a string pool, with case-sensitive comparisons. 

To initialise values of this class, you need to use the operator() functions 

on the RStringPool. 

This class performs comparisons in a non-folded (case sensitive) manner. 

@see RStringPool

@publishedAll

@released

*/

	{

 public:

	inline RString Copy();

	inline operator RStringToken() const;

	inline TBool operator==(const RString& aVal) const;

	inline TBool operator!=(const RString& aVal) const;

	friend class RStringPool;

	friend class RStringToken;

	};

class RStringF : public RStringBase

/** 

A string that is stored in a string pool, with case-insensitive comparisons.

To initialise values of this class, you need to use the operator() functions 

on the RStringPool. 

Comparisons with this class use folded (case insensitive) comparisons. 

@publishedAll

@released

*/

	{

 public:

	inline RStringF Copy();

	inline operator RStringTokenF() const;

	inline TBool operator==(const RStringF& aVal) const;

	inline TBool operator!=(const RStringF& aVal) const;

	friend class RStringPool;

	friend class RStringTokenF;

	};

/**

A pointer to a string table.

@publishedAll

@released

*/

struct TStringTable

	{

	// The number of elements in the table

	/** The number of elements in the table. */

	TUint iCount;

	// A pointer to an array of pointers to the strings

	/** A pointer to an array of pointers to the strings. */

	const void* const * iTable;	

	// ETrue if the table should be considered case-sensitive.

	/** Flag that is ETrue if the table should be considered case-sensitive, otherwise 

	EFalse. */

	TBool iCaseSensitive;

	};

// Include the inline functions

#include <stringpool.inl>

#endif // __STRINGPOOL_H__