/*

* Copyright (c) 2006 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 __SDP_ATTRIBUTE_PARSER_H__

#define __SDP_ATTRIBUTE_PARSER_H__

#include <btsdp.h>

#include "StaticArrayC.h"

class MSdpAttributeNotifier;

/*! 

  @class TSdpAttributeParser

  @discussion An instance of TSdpAttributeParser is used to check an SDP 

  attribute value, and read selected parts

  */

class TSdpAttributeParser : public MSdpAttributeValueVisitor 

    {

public:

/*!

  @enum TNodeCommand

  @discussion The command to be carried out at a node

  @value ECheckType check the type of the value

  @value ECheckValue check the type and the value

  @value ECheckEnd check that a list ends at this point

  @value ESkip do not check this value - can not match a list end

  @value EReadValue pass the value onto the observer

  @value EFinished marks the end of the node list

  */

    enum TNodeCommand

        {

        ECheckType,     

        ECheckValue,  

        ECheckEnd,      

        ESkip,        

        EReadValue,    

        EFinished

        };

/*! 

  struct SSdpAttributeNode

  @discussion An instance of SSdpAttributeNode is used to determine how

  to parse an SDP attribute value data element

  */

    struct SSdpAttributeNode

        {

        /*! @var iCommand the command for the node */

        TNodeCommand iCommand;

        /*! @var iType the expected type */

        TSdpElementType iType;

        /*! @var iValue the expected value for ECheckValue, the value of aKey

        passed to the observer for EReadValue */

        TInt iValue;    

        };

    typedef const TStaticArrayC<SSdpAttributeNode> TSdpAttributeList;

/*!

  @function TSdpAttributeParser

  @discussion Construct a TSdpAttributeParser

  @param aNodeList the list of expected nodes 

  @param aObserver an observer to read specified node values

  */

    TSdpAttributeParser(TSdpAttributeList& aNodeList, MSdpAttributeNotifier& aObserver);

/*!

  @function HasFinished

  @discussion Check if parsing processed the whole list

  @result true is the index refers to the EFinished node

  */

    TBool HasFinished() const;

public: // from MSdpAttributeValueVisitor

/*!

  @function VisitAttributeValueL

  @discussion Process a data element

  @param aValue the data element 

  @param aType the type of the data element

  */

    void VisitAttributeValueL(CSdpAttrValue& aValue, TSdpElementType aType);

/*!

  @function StartListL

  @discussion Process the start of a data element list

  @param aList the data element list 

  */

    void StartListL(CSdpAttrValueList& aList);

/*!

  @function EndListL

  @discussion Process the end of a data element list

  */

    void EndListL();

private:

/*!

  @function CheckTypeL

  @discussion 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;

/*!

  @function CheckValueL

  @discussion 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;

/*!

  @function ReadValueL

  @discussion Pass the data element value to the observer

  @param aValue the value of the current data element.

  */

    void ReadValueL(CSdpAttrValue& aValue) const;

/*!

  @function CurrentNode

  @discussion Get the current node

  @result the current node

  */

    const SSdpAttributeNode& CurrentNode() const;

/*!

  @function AdvanceL

  @discussion Advance to the next node. Leaves with KErrEof if at the finished node.

  */

    void AdvanceL();

private:

    /*! @var iObserver the observer to read values */

    MSdpAttributeNotifier& iObserver;

    /*! @var iNodeList a list defining the expected structure of the value */

    TSdpAttributeList& iNodeList;

    /*! @var iCurrentNodeIndex the index of the current node in iNodeList */

    TInt iCurrentNodeIndex;

    };

#endif // __SDP_ATTRIBUTE_PARSER_H__