/*

* 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:   interface for creating custom extensions

*

*/

#ifndef __M_ALF_EXTENSION_FACTORY__

#define __M_ALF_EXTENSION_FACTORY__

#include <e32base.h>

class CAlfLayoutManager;

class CHuiEnv;

// binary

enum THuiInterfaceSupport

    {                                   // Cast to:

    EHuiObjectTypeVisual = 0x0001,      // CHuiVisual

    EHuiObjectTypeLayout = 0x0002,      // CHuiLayout   

    EHuiObjectTypeControl = 0x0004 ,    // CHuiControl

    EHuiObjectTypeControlGroup = 0x0008,// CHuiControlGroup

    EHuiObjectTypeBrush = 0x0010,       // CHuiBrush 

    EHuiObjectTypeDisplay = 0x0020,     // CHuiDisplay

    EHuiObjectTypeCustom = 0x0040,      // For extension to decide

    EHuiObjectTypeCurvePathProvider = 0x0080, // Implemented by object which shares curve path

    EHuiInterfaceMappingFunction = 0x00010000, // MHuiMappingFunction

    EHuiInterfaceVisualOwner = 0x00020000,      // MHuiVisualOwner

    EAlfBrushHandler = 0x00040000,  // CAlfBrushHandler, needed for controlling brush ownership

    EAlfTextStyleHandler = 0x00080000,	// TAlfTextStyleHandler, needed for mapping client and server side text styles    

    EAlfVisualHandler = 0x00100000	// CAlfVisualHandler

    };

class MAlfInterfaceProvider

    {

public:

    /**

    * Request to pointer of given type matching to given handle. 

    * Leaves if object not found i.e. always returns pointer on completion

    */

    virtual TAny* GetInterfaceL(const THuiInterfaceSupport& aType, TInt aHandle) = 0;

    /**

    * Request identifier for pointer of given type 

    * On error returns KErrNotFound

    */

    virtual TInt GetHandleFromInterface(const THuiInterfaceSupport& aType, TAny* aInterface) = 0;

    /**

    * Returns common layoutmanager or null

    */

    virtual CAlfLayoutManager* LayoutManager() const = 0;

    /**

    * Returns common hitchcock environment or null

    */

    virtual CHuiEnv* SharedHuiEnv() const = 0;

    /**

    * Request to make current command (during MAlfExtension::HandleCmd) asynchronous

    * returns command id that is needed for completing the command later on

    *

    * exntension should take references to buffers (in/out) in case it wants to modify client message

    * before completing it

    */

    virtual TInt HandleCurrentCommanndAsynch() = 0;

    /**

    * Complete asynch command, if MAlfExtension implementing object utilizes asynch commands

    * it should also take care that those messages are completed at latest when the extension is being 

    * destoryed. FW will panic the client in case of orphean messages

    */    

    virtual void CompleteCmd(TInt aCommadIdentifier, TInt aResult = KErrNone) = 0;

    /** ! Future proofing */

    virtual void AlfInterfaceProviderExtension(const TUid& aExtensionUid, TAny** aExtensionParams) = 0;

    };

class MAlfExtension

    {

    public:

        /**

        * Free resources for instance, usually delete this

        */

        virtual void Release() = 0;

        /**

        * Returns pointer of correct type or null

        * @param aInterface     type of interface requested

        * @return               Pointer or null depending whether interface is implemented 

        */

        virtual TAny* GetInterface(const THuiInterfaceSupport& aInterface) = 0;

        /**

        * Handles command from controller

        * @param aCommandId     Command identifier, values below EAlfLastReservedOpCmd (= 10000)

        *                       are reserved for tookit fw and should not be utilized in app 

        *                       specific extensions.

        * @param aInputBuffer   Additional data attached to command

        * @param aResponse      Response to be passed back to commander

        * @leave                Any system wide error code

        */

        virtual void HandleCmdL(TInt aCommandId, const TDesC8& aInputBuffer, TDes8& aResponse) = 0;

    };

class MAlfExtensionFactory

    {

    public:

        /**

        * Creates new instace of required type (unique for factory)

        * Must not take ownership of created object

        * 

        * @param aObjectId      Object type required

        * @param aInputBuffer   Additional data attached to object construction

        * @param aResolver      Reference to Interface resolver 

        * @leave                Any system wide error code

        */

        virtual MAlfExtension* CreateExtensionL(const TInt aObjectId, const TDesC8& aInitialParams, MAlfInterfaceProvider& aResolver) = 0;

        /**

        * Free resources for instance, usually delete this

        */

        virtual void Release() = 0; 

    };

#endif