/*

* Copyright (c) 2008 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 CPACTIONHANDLERTHREAD_H_

#define CPACTIONHANDLERTHREAD_H_

#include <e32base.h>

#include <eikenv.h>

#include <eikappui.h>

class MLiwInterface;

class CLiwGenericParamList;

class CCPActionManager;

/**

 * The function to be passed as an argument to RThread::Create.

 * 

 * It just calls CCPActionHandlerThread::ThreadFunction. The only

 * reason this declaration is in the header file is to let

 * CCPActionHandlerThread declare friendship with this funcion.

 * 

 * @param aParam pointer to CCPActionHandlerThread object

 * @return error code

 */

TInt CPExecutionThreadFunction( TAny* aParam );

/**

 * Action handler thread.

 * 

 * Provides easy-to-use interface for executing plugin actions

 * in a separate thread.

 * @since S60 5.0

 */

class CCPActionHandlerThread: public CBase

    {

    friend TInt CPExecutionThreadFunction( TAny* );

public:

    /**

     * Creates new instance of CCPActionHandlerThread.

     * 

     * @return new instance of CCPActionHandlerThread

     */

    static CCPActionHandlerThread* NewL();

    /**

     * Creates new instance of CCPActionHandlerThread.

     * 

     * @return new instance of CCPActionHandlerThread

     */

    static CCPActionHandlerThread* NewLC();

    /**

     * Destructor.

     * Stops the action execution thread.

     */

    ~CCPActionHandlerThread();

    /**

     * Executes an action handler action in the action execution thread.

     * 

     * @param aActionParams action parameters

     */

    void ExecuteL( const CLiwGenericParamList& aActionParams );

    /**

     * Starts the action execution thread.

     * 

     * Creates a new instance of action execution thread

     * provided it is not running already.

     */

    void StartExecutionThreadIfNeededL();

    /**

     * Checks whether action execution thread is alive.

     * 

     * @return ETrue if the thread is alive, EFalse otherwise.

     */

    TBool ExecutionThreadRunning();

private:

    /**

     * Constructor.

     */

    CCPActionHandlerThread();

    /**

     * 2nd phase constructor.

     */

    void ConstructL();

    /**

     * This function is run is a separate thread. It creates

     * CServerEikonEnv and CServerAppUi objects, which provide

     * a trap cleanup and an active scheduler for the thread and

     * then starts the active scheduler.

     * 

     * @return error code

     */

    TInt ThreadFunction();

private: // internal data types

    /**

     *  EIkonEnv for the server process.

     */

    class CServerEikonEnv : public CEikonEnv

        {

    public:

        void DestroyEnvironment();

        void ConstructL();

        };

    /**

     * EikAppUi for the server process.

     */

    class CServerAppUi : public CEikAppUi

        {

    public:

        ~CServerAppUi();

        void ConstructL();

        };

    /**

     * A simple active object for executin actions.

     * Objects of this class are created and destroyed

     * by action execution thread. 

     */

    class CActionExecutorAO: public CActive

        {

    public:

        /**

         * Factory method.

         */

        static CActionExecutorAO* NewL();

        /**

         * Factory method. 

         */

        static CActionExecutorAO* NewLC();

        /**

         * Destructor.

         */

        ~CActionExecutorAO();

        /**

         * The RunL method which is run whever an action needs

         * to be executed in the action execution thread.

         * It just executes the action using the parameters

         * supplied with a call to SetActionParams. If that

         * parameters are NULL, it stops the active scheduler

         * thus terminating action execution thread.

         */

        void RunL();

        /**

         * A dummy cancel method required by Symbian.

         */

        void DoCancel();

        /**

         * Returns a pointer to this active object's iStatus

         * member variable.

         */

        TRequestStatus* RequestStatus();

        /**

         * TODO

         * Sets paramters of the action to be executed in RunL.

         * This method is supposed to be called from the main CPS thread.

         * @param aActionParams action parameters

         */

        void SetActionParams( const CLiwGenericParamList* aActionParams );

    private:

        /**

         * Constructor.

         */

        CActionExecutorAO();

        /**

         * 2nd phase constructor.

         */

        void ConstructL();

    private:

        /**

         * Parameters of the action to be executed in RunL.

         * Not own.

         */

        const CLiwGenericParamList* iActionParams;

        /**

         * Action manager instance.

         * Own.

         */

        CCPActionManager* iActionManager;

        };

private: // data

    /**

     * Handle to the action execution thread.

     * Own.

     */

    RThread iActionExecThread;

    /**

     * Active object created in the action execution thread.

     * Own.

     */

    CActionExecutorAO *iActionExecutorAO;

    /**

     * ETrue if action execution thread was started at least once.

     */

    TBool iActionExecThreadStarted;

    /**

     * A counter for naming action execution thread.

     * 

     * Every action execution thread has a number appended to its name.

     * When the thread dies (i.e. as a result of panic in a plugin), a

     * new instance of that thread is started with the number in the name

     * increased by one.

     */

    TUint iThreadNum;

    };

#endif /* CPACTIONHANDLERTHREAD_H_ */