/*

* Copyright (c) 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:  Reads selected parts of SDP attribute values.

*

*/

#ifndef __SDP_ATTRIBUTE_PARSER_H__

#define __SDP_ATTRIBUTE_PARSER_H__

// INCLUDES

#include <btsdp.h>

// FORWARD DECLARATIONS

class MSdpAttributeNotifier;

// CLASS DECLARATIONS

/**

* TSdpAttributeParser

* An instance of TSdpAttributeParser is used to check an SDP

* attribute value, and read selected parts

*/

class TSdpAttributeParser : public MSdpAttributeValueVisitor

    {

    public:     // Enumerations

        /**

        * TNodeCommand

        * The command to be carried out at a node

        * ECheckType. Check the type of the value

        * ECheckValue. Check the type and the value

        * ECheckEnd. Check that a list ends at this point

        * ESkip. Do not check this value - can not match a list end

        * EReadValue. Pass the value onto the observer

        * EFinished. Marks the end of the node list

        */

        enum TNodeCommand

            {

                ECheckType,

                ECheckValue,

                ECheckEnd,

                ESkip,

                EReadValue,

                EFinished

            };

        /**

        * SSdpAttributeNode

        * An instance of SSdpAttributeNode is used to determine how

        * to parse an SDP attribute value data element

        */

        struct SSdpAttributeNode

        {

            /** iCommand the command for the node */

            TNodeCommand iCommand;

            /** iType the expected type */

            TSdpElementType iType;

            /** iValue the expected value for ECheckValue,the value of aKey

            * passed to the observer for EReadValue

            */

            TInt iValue;

        };

        typedef const TStaticArrayC< SSdpAttributeNode > TSdpAttributeList;

        /**

        * TSdpAttributeParser

        * Construct a TSdpAttributeParser

        * @param aNodeList the list of expected nodes

        * @param aObserver an observer to read specified node values

        */

        TSdpAttributeParser( TSdpAttributeList& aNodeList,

                             MSdpAttributeNotifier& aObserver );

        /**

        * HasFinished

        * Check if parsing processed the whole list

        * @return true is the index refers to the EFinished node

        */

        TBool HasFinished() const;

    public: // from MSdpAttributeValueVisitor

        /**

        * VisitAttributeValueL

        * Process a data element

        * @param aValue the data element

        * @param aType the type of the data element

        */

        void VisitAttributeValueL( CSdpAttrValue& aValue,

                                   TSdpElementType aType );

        /**

        * StartListL

        * Process the start of a data element list

        * @param aList the data element list

        */

        void StartListL( CSdpAttrValueList& aList );

        /**

        * EndListL

        * Process the end of a data element list

        */

        void EndListL();

    private:    // Functions from base classes

        /**

        * CheckTypeL

        * Check the type of the current node is the same as

        * the specified type.

        * @param aElementType the type of the current data element

        */

        void CheckTypeL( TSdpElementType aElementType ) const;

        /**

        * CheckValueL

        * Check the value of the current node is the same as the specified value

        * @param aValue the value of the current data element.

        */

        void CheckValueL( CSdpAttrValue& aValue ) const;

        /**

        * ReadValueL

        * Pass the data element value to the observer

        * @param aValue the value of the current data element.

        */

        void ReadValueL( CSdpAttrValue& aValue ) const;

        /**

        * CurrentNode

        * Get the current node

        * @return the current node

        */

        const SSdpAttributeNode& CurrentNode() const;

        /**

        * AdvanceL

        * Advance to the next node. Leaves with KErrEof

        * if at the finished node.

        */

        void AdvanceL();

    private:    // data

        /** iObserver the observer to read values */

        MSdpAttributeNotifier& iObserver;

        /** iNodeList a list defining the expected

        * structure of the value

        */

        TSdpAttributeList& iNodeList;

        /** iCurrentNodeIndex the index of the current node in iNodeList */

        TInt iCurrentNodeIndex;

    };

#endif // __SDP_ATTRIBUTE_PARSER_H__

// End of File