/*

* Copyright (c) 2006-2009 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:  Composer image active object

*

*/

#include <e32msgqueue.h>

#include "mdeobject.h"

#include "mdeobjectquery.h"

#include "harvesterexifutil.h"

#include "mdeharvestersession.h"

#ifndef __CIMAGECOMPOSERAO_H__

#define __CIMAGECOMPOSERAO_H__

_LIT( KImageComposerPanic, "CImageComposerAO" );

class CMdERelationQuery;

class CImageComposerAO : public CActive, public MMdEQueryObserver

    {

    public:

        enum TRequestType

            {

            ERequestReady = 0,

            ERequestGetObject,

            ERequestCompose

            };

        /**

        * Construction

        */

        static CImageComposerAO* NewL();

        /**

        * Destruction

        */

        virtual ~CImageComposerAO();

        /**

         * Adds new item to composing queue.

         * @param aItems  Items to add to the queue.

         * @param aForce  Force composing to items in aItems array

         */

        void AddToQueue( const RArray<TItemId>& aItems, TBool aForce );

        /**

         * Checks if composing is completed.

         * @return ETrue, if complete.

         */

        TBool IsComposingComplete();

        /**

         * Sets mde client session to be used by this composer.

         * @param aSession  Mde client session.

         */

        void SetSession( CMdESession* aSession );

        /**

         * Remove MdE client session used by this composer.

         */

        void RemoveSession();

        /**

         * Writes location data to Exif.

         * @param aMdeObject  Mde object of the image.

         * @param aLocationObject  Related mde location object.

         */

        void DoWriteExifL( CMdEObject* aMdEObject, CMdEObject* aLocationObject );

    public: // from MMdEQueryObserver

	    /**

	     * Callback to handle new results received from a query.

	     * From MMdEQueryObserver.

	     */

        virtual void HandleQueryNewResults( CMdEQuery& aQuery, TInt aFirstNewItemIndex,

            TInt aNewItemCount );

	    /**

	     * Callback to handle new results received from a query.

	     * From MMdEQueryObserver.

	     */

        virtual void HandleQueryNewResults( CMdEQuery& aQuery, TInt aNewObjectItemCount, 

            TInt aNewRelationItemCount, TInt aNewEventItemCount );

	    /**

	     * Callback to handle all results of a completed query.

	     * From MMdEQueryObserver.

	     * @param aQuery  Completed query

	     * @param aError  Error code, KErrNone on success.

	     */

        virtual void HandleQueryCompleted( CMdEQuery& aQuery, TInt aError );

    protected:

    	/**

    	 * RunL

    	 * From CActive.

    	 */

        virtual void RunL();

    	/**

    	 * DoCancel

    	 * From CActive.

    	 */

        virtual void DoCancel();

    	/**

    	 * RunError. Error handler in case RunL() leaves.

    	 * From CActive.

    	 * @param aError  Leave code from RunL.

    	 * @return  Error code. KErrNone if error was handled.

    	 */

        virtual TInt RunError( TInt aError );

    private:

        /**

        * Private constructor

        */    

        CImageComposerAO();

        /**

        * 2nd phase construction

        */    

        void ConstructL(); // second-phase constructor

        /**

         * Gets an object from MdE DB.

         * Leave on queue errors.

         * Leaves with KErrNotFound, if object is not found.

         * 

         * @param Returned value of current composing request's object ID. 

         *        Value is changed when item is read from composing queue.

         */

        void GetObjectFromMdeL(TItemId& aMdEObjectId);

        /**

         * Writes (=composes) new metadata to a image file.

         */

        void ComposeL();

        /**

         * SetNextRequest

         * Sets next state for this active object's RunL.

         * @param aNextRequest  State to set.

         */

        void SetNextRequest( TRequestType aNextRequest );

        /**

         * @brief Starts the write of GPS tags to a image file.

         * 

         * Starts a query to search for related location data in mde.

         * If found, HandleQueryCompleted will start adding found info

         * to image file.

         * 

         * @param aObjectId  Object to whichs add GPS tags.

         * 

         * @see HandleQueryCompleted

         * @see StartWritingGPSTagsL

         * @see DoWriteExifL

         */

        void WriteGPSTagsL( TItemId aObjectId );

        /**

         * Checks if given mime type is JPEG image.

         * @param aMimeType  a mime type string.

         * @return ETrue if mime type is image/jpeg.

         */

        static TBool IsJpeg( const TDesC& aMimeType );

        /**

         * Starts writing GPS tags to image file.

         * @param aQuery  Mde query which contains results for related

         *                location object query.

         */

        void StartWritingGPSTagsL( CMdEQuery& aQuery );

        /**

         * Converts a TDateTime object's date to a Exif GPS date string.

         *

         * @param aTime  TDateTime object to extract the date from.

         * @param aTgtDes  Target descriptor for the string.

         */

        void TimeToGpsDateStringL( TTime aTime, TDes& aTgtDes );

        /**

         * Converts a TTime object's time to a Exif GPS time string.

         *

         * @param aTime  TDateTime object to extract the time from.

         * @param aTgtDes  Target descriptor for the string.

         */

        void TimeToGpsTimeStringL( TDateTime aTime, TDes8& aTgtDes );

        /**

         * CompareItemIds

         */

		static TInt CompareTItemIds( const TItemId& aLeft, const TItemId& aRight )

			{

			return aLeft - aRight;

			}

    private:

    	/** Pointer to a mde object */

        CMdEObject* iMdeObject;

        /** Pointer to mde session to use */

        CMdESession* iSession;

        CMdEHarvesterSession* iMdEHarvesterSession;

        /** Next state of this active object's RunL() */

        TRequestType iNextRequest;

        /** Queue of items to compose */

        RArray<TItemId> iItemQueue;

        /** A relation query used to seach for related location objects */

        CMdERelationQuery* iRelationQuery;

        /** Mde default namespace. NOT OWN. */

        CMdENamespaceDef* iDefaultNamespace;

        /** Image Object Def. NOT OWN. */

        CMdEObjectDef* iImageObjectDef;

        /** "Base" Object Def. NOT OWN. */

        CMdEObjectDef* iObjectDef;

        /** Location Object Def. NOT OWN. */

        CMdEObjectDef* iLocationObjectDef;

        /**

         * Array used to skip new coming id after explicit change of

         * MdE object in composer.

         */

        RArray<TItemId> iNextItemsSkip;

        /**

         * Array of item id's which will be forced to be composed

         * No timestamp checking will be done for these objects

         */

        RArray<TItemId> iForceObjectIds;

        CHarvesterExifUtil* iExifUtil;

        RFs iFs;

    };

#endif // __CIMAGECOMPOSERAO_H__