/*

* 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:  Abstract base class for filter when listing triggers.

*

*/

#ifndef LBTTRIGGERFILTERBASE_H

#define LBTTRIGGERFILTERBASE_H

#include <e32base.h>

#include <s32strm.h>

/**

 * Abstract base class for filter when listing triggers from 

 * Location Triggering Server.

 *

 * @lib lbt.lib

 * @since S60 5.1

 */

class CLbtTriggerFilterBase : public CBase

    {

public:

    /**

     * Specifies the type of the filter

     */

    enum TFilterType

        {

        /**

         * Filter based on the trigger entry's attribute value.

         */

        EFilterByAttribute = 1,

        /**

         * Filter based on the geographical area.

         */

        EFilterByArea = 2,

        /**

         * Composite filter.

         */

        EFilterComposite = 3

        };

    /**

     * Returns the type of filter.

     *

     * @return The type of the filter.

     */

    virtual TFilterType Type() const = 0;

    /**

     * Destructor.

     */

    IMPORT_C virtual ~CLbtTriggerFilterBase();

    /**

     * Internalizes the trigger condition object's details and attributes 

     * from stream.

     *

     * The presence of this function means that the standard templated 

     * operator>>() ( defined in s32strm.h ) is available to internalize objects 

     * of this class.

     *

     * @param[in] aStream Stream from which the object should be internalized.

     */

    IMPORT_C void InternalizeL( RReadStream& aStream );

    /**

     * Externalizes the trigger condition object's details and attributes

     * to stream.

     *

     * The presence of this function means that the standard templated 

     * operator<<() ( defined in s32strm.h ) is available to externalize objects 

     * of this class.

     *

     * @param[in] aStream Stream to which the object should be externalized.

     */

    IMPORT_C void ExternalizeL( RWriteStream& aStream ) const;

protected:    

    /**

     * Constructor.

     */

    CLbtTriggerFilterBase();

    /**

     * Internalize method that subclass must implement.

     * @param[in] aStream Stream from which the object should be internalized.

     */

    virtual void DoInternalizeL( RReadStream& aStream ) = 0;

    /**

     * Externalize method that subclass must implement.

     * @param[in] aStream Stream to which the object should be externalized.

     */

    virtual void DoExternalizeL( RWriteStream& aStream ) const = 0;

private:

    /**

     * By default, prohibit copy constructor

     */

    CLbtTriggerFilterBase( const CLbtTriggerFilterBase& );

    /**

     * Prohibit assigment operator

     */

    CLbtTriggerFilterBase& operator= ( const CLbtTriggerFilterBase& );

    };

#endif // LBTTRIGGERFILTERBASE_H