/*

* Copyright (c) 2003-2009 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:

* Name          : SdpUtil.h

* Part of       : SDP Codec

* Interface     : -

* Version       : 1.0

*

*/

/**

 @internalComponent

*/

#ifndef SDPUTIL_H

#define SDPUTIL_H

//  INCLUDES

#include <e32base.h>

#include <stringpool.h>

#include <e32std.h>

#include "_sdpdefs.h"

// FORWARD DECLARATIONS

class RReadStream;

class RWriteStream;

class CSdpConnectionField;

class CSSdpKeyField;

class CSdpOriginField;

class TInetAddr;

// CLASS DECLARATION

/**

 *	Common utilities used in the implementation of the SDP codec.

 *  Utility class, cannot be instantiated

 */

class SdpUtil

	{

    public: // New functions

        /**

         *  Generic method that checks that all aValue's chars are not on illegal charset

         *

         *  @param aIllegalChars Illegal character set

         *  @param aValue String to be checked

         *  @param aStart Start position of the string

         *  @param aEnd End position of the string

         *  @return Validity of the string

         */

		static TBool IsValidCharSet( 

            const TDesC8& aIllegalChars, const TDesC8& aValue, TInt aStart, TInt aEnd );

        /**

         *  Checks that token list is valid (tokens with space as delimiter)

         *

         *  @param aValue String containing tokens

         *  @return Validity of the string

         */

		static TBool IsTokenList( const TDesC8& aValue );

        /**

         *  Checks that the token is valid (substring inside string)

         *

         *  @param aValue String containing the token

         *  @param aStart Start position of the token inside the string

         *  @param aEnd End position of the token inside the string

         *  @return Validity of the token

         */

		static TBool IsToken( const TDesC8& aValue, TInt aStart, TInt aEnd );

        /**

         *  Checks that the token is valid

         *

         *  @param aValue Token string 

         *  @return Validity of the token

         */

		static TBool IsToken( const TDesC8& aValue );

        /**

         *  Checks that the byte string is valid (substring inside string)

         *

         *  @param aValue String 

         *  @param aStart Start position of the byte string inside the string

         *  @param aEnd End position of the byte string inside the string

         *  @return Validity of the byte string

         */

		static TBool IsByteString( const TDesC8& aValue, TInt aStart, TInt aEnd );

        /**

         *  Checks that the byte string is valid

         *

         *  @param aValue String containing the token        

         *  @return Validity of the byte string

         */

		static TBool IsByteString( const TDesC8& aValue );

        /**

         *  Checks that the substring is a token-byte string pair with colon char

         *  as delimiter of the two strings

         *

         *  @param aValue String containing the pair

         *  @param aStart Start position of the string pair

         *  @param aEnd End position of the string pair        

         *  @return Validity of the pair

         */

		static TBool IsTokenTextPair( 

            const TDesC8& aValue, TInt aStart, TInt aEnd );

        /**

         *  Checks that the string conatins valid token-byte string pair with color

         *  char as delimiter of the two strings

         *

         *  @param aValue String containing the pair        

         *  @return Validity of the byte string

         */

		static TBool IsTokenTextPair( const TDesC8& aValue );

        /**

         *  Checks that the string does not contain any whitespace characters

         *

         *  @param aValue String        

         *  @return Validity of the string

         */

		static TBool IsNonWhitespace( const TDesC8& aValue );

        /**

         *  Checks that the string contains a valid NTP-time element

         *

         *  @param aValue String

         *  @return Validity of the string

         */

		static TBool IsValidNtpTime( const TDesC8& aValue );

        /**

         *  Divides the buffer into a number of lines. Each line is marked

         *  as a TPtrC8 object and added to array that is returned to the user

         *  NOTE! Each line in the returned array ends in LF character

         *  NOTE! The aLines must end in LF character, not '\0' character

         *

         *  @param aLines Buffer that contains all the string

         *  @param aErrCode Error code that is used on leave situations, when the

         *                  aLines parameter contains invalid string set

         *  @return Array that contains the division of buffer to lines

         */

        static RArray<TPtrC8> DivideToLinesL( 

            const TDesC8& aLines, TInt aErrCode );

        /**

         *  Parses elements from each line. The first item in the returned array

         *  is the field attribute and equal character (e.g. "a=", "c="), following

         *  elements are parsed from the string using space character as delimiter

         *

         *  @param aLine String containing line that ends to LF character

         *  @param aErrCode Error code that is used on leave situations, when

         *                  the contents of aLine are illegal

         *  @return Array that contains the division of string to elements

         */

        static RArray<TPtrC8> GetElementsFromLineL( 

            const TDesC8& aLine, TInt aErrCode );

        /**

         *  Parses elements from each line. The first item in the returned array

         *  is the field attribute and equal character (e.g. "a=", "c="), following

         *  elements are parsed from the string using aDelimiter as delimiter

         *

         *  @param aLine String containing line that ends to LF character

         *  @param aDelimiter Delimiter character

         *  @param aErrCode Error code that is used on leave situations, when

         *                  the contents of aLine are illegal

         *  @return Array that contains the division of string to elements

         */

        static RArray<TPtrC8> GetElementsFromLineL( 

            const TDesC8& aLine, TChar aDelimiter, TInt aErrCode ); 

        /**

         *  Parses elements from each line. The first item in the returned array

         *  is the field attribute and equal character (e.g. "a=", "c="), following

         *  elements are parsed from the string using space character as delimiter

         *

         *  @param aLexer Lexer that has been initialized with the string

         *  @param aErrCode Error code that is used on leave situations, when

         *                  the contents of aLine are illegal

         *  @return Array that contains the division of string to elements

         */       

        static RArray<TPtrC8> GetElementsFromLineL( 

            TLex8& aLexer, TChar aDelimiter, TInt aErrCode );

        /**

         *  Checks if the string contains only POS-DIGIT characters

         *

         *  @param aDes String

         *  @return Validity of POS-DIGIT string

         */

        static TBool IsPosDigit( const TDesC8& aDes );

        /**

         *  Checks if the string contains only DIGIT characters

         *

         *  @param aDes String

         *  @return Validity of DIGIT string

         */

        static TBool IsDigit( const TDesC8& aDes );

        /**

         *  Checks if the string contains valid characters

         *  

         *  @param aValidChars Valid characters allowed in the string

         *  @param aDes String

         *  @return Validity of the string

         */

        static TBool IsValidChars( const TDesC8& aValidChars, const TDesC8& aDes );                

        /**

         *  Checks if the string contains only token characters

         *

         *  @param aValue String

         *  @return Validity of the string

         */

        static TBool IsTokenChar( const TDesC8& aValue );

        /**

         *  Checks if the character is a valid token character

         *

         *  @param aChar Character

         *  @return Validity of the character

         */

		static TBool IsTokenChar( TChar aChar );

        /**

         *  Checks if the string is a valid token. The string can contain slash character,

         *  which divides the line into two tokens. The two tokens are then individually

         *  verified.

         *

         *  @param aValue String

         *  @return Validity of the string

         */

		static TBool IsTokenCharWithOptionalSlash( const TDesC8& aValue );

        /**

         *  Checks if the string is a valid token. The string can contain space characters,

         *  which divides the string into a number of tokens. Each token is then individually

         *  verified.

         *

         *  @param aValue String

         *  @return Validity of the string

         */

		static TBool IsTokenCharWithSpacesL( const TDesC8& aValue );

        /**

         *  Checks if the string is a valid token. The string can contain slash character,

         *  which divides the line into two tokens. The two tokens are then individually

         *  verified.

         *

         *  @param aValue String

         *  @return Validity of the string

         */

		static void EncodeBufferL( 

            const TDesC8& aValue, TInt aIndex, RWriteStream& aStream );

        /**

         *  Sets default network type ("IN") and default address type ("IP4" or "IP6")

         *  to variables given as parameters

         *  

         *  @param aPool String pool

         *  @param aInetAddr Internet address

         *  @param aNetType Network type

         *  @param aAddressType Address type

         */

        static void SetDefaultNetTypeAndAddrType( 

            RStringPool aPool, const TInetAddr& aAddress,

            RStringF& aNetType, RStringF& aAddressType );

        /**

         * Skips spaces until next line break, if the line break can be found.

         * @param aLexer

         * @return ETrue if the line break was found, otherwise EFalse. 

         */

        static TBool SkipSpacesUntilNextLineBreak( TLex8& aLexer );

    private:

        /**

         *  After the field tag has been parsed out, all the field elements are

         *  parsed in this method

         *

         *  @param aArray Reference to the array that contains the chopped elements

         *  @param aLexer Used lexer

         *  @param aDelimiter Delimiter character that determines the separation of elements

         *  @param aErrCode The error code that is used on leaves, when the argument is invalid

         */

        static void ChopElementsFromLineL( 

            RArray<TPtrC8>& aArray, TLex8& aLexer, TChar aDelimiter, TInt aErrCode );

        /**

         *  Private constructor         

         *  This class can never be instantiated

         */

        SdpUtil();

	};

#endif