/*

* Copyright (c) 2007-2008 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:  Implementation of model interface base

 *

*/

#ifndef MULPUSHMODE_H

#define MULPUSHMODE_H

//Includes

#include <osn/ustring.h>

#include <mul/muldatapath.h>

#include "mul/imulwidget.h"

namespace Alf

    {

//Forward Declaration

class MulVisualItem;

class MulCacheManager;

class MulPageDataWindow;

class MulAlfModelImpl;

/**

 *  Base implementation class for pull/push model.

 *  @lib 

 */

class MulPushMode

    {

public: 

	/**

	 * C++ constructor.

	 * 

	 * @param aDataWindow DataWindow for model

	 */

    MulPushMode( MulPageDataWindow& aDataWindow );

	/**

	 * Destructor

	 */

	virtual ~MulPushMode();

	/**

	 * Informs the data model that new items have been added to client's

	 * internal model. Data model is expected to sync its indices as a 

	 * result.

	 * 

	 * @param aIndex Position where items were inserted.

	 * @param aCount Number of items inserted.

     * @return true if highlight is modified else false.	 

	 */ 

	bool Insert( int aIndex, int aCount, 

                         const MulDataPath& aPath = MulDataPath() );

    /**

     * Informs the data model that items have been removed from the client's.

     * internal data model.Data model is expected to sync its indices as a 

     * result.

     * 

     * @param aIndex Position from where items have to be removed.

     * @param aCount Number of items to be removed.

     * @return true if highlight is modified else false.

     */ 

    bool Remove( int aIndex, int aCount, 

                         const MulDataPath& aPath = MulDataPath() );

    /**

     * Informs the data model that an item has been updated in the client's

     * internal model. Data model will use to input to determine whether

     * a visualization change is required.

     * 

     * @param aIndex Position from where items have to be updated.

     * @param aCount Number of items to be updated.

     */ 

	virtual void Update( int aIndex, int aCount, 

                         const MulDataPath& aPath = MulDataPath() );

    /**

      * A refresh data request. Informs that the data model has to be 

      * repopulated with mentioned number of items. So the data model

      * will remove all the existing data and issue request to the 

      * provider for new data.

      * 

      * @param aCount Number of items to be repopulated.

      * @param aPath  Path of parent item in the data hierarchy. 

      *               Default is Null path i.e. no parent.

      */ 						 

	virtual void Refresh( int aCount, const MulDataPath& aPath = MulDataPath());						 

	/**

     * Provide data for the specified item. This is a unified API for 

     * adding & updating data. 

     *

     * @param aIndex Position of item to be updated.

     * @param aVisualItem Collection of attributes. Ownership is transfered.

     * @throw Invalid Argument, in case index is out of bound or visual 

     *                         item is NULL.

     * @throw Logic Error, in case item could not be updated.

     */ 

	virtual void SetData( int aIndex, 

						  std::auto_ptr<MulVisualItem> aVisualItem, 

                          const MulDataPath& aPath);

	 /**

	  * Get the data for item at the specified index.

	  *

	  * @param aIndex Position of item in the data model.

	  * @return A constant reference to the data at the given index.

	  */ 

	const MulVisualItem* Data( int aIndex, const MulDataPath& aPath ) const;

	 /**

	  * Get the count of items in the model.

	  *

	  * @return Count of items in the model.

	  */ 

	int Count(const MulDataPath& aPath ) const; 

	/**

     * Set the default logical template id for widget elements. 

     * Logical templates map to visualization of the element(s).

     * 

     * @param aTemplateId Logical template id for the widget elements.

     */ 

	virtual void SetTemplate( mulwidget::TLogicalTemplate aTemplateId ) ;

    /**

     * Returns the default template. 

     * 

     * @return Logical template id for the widget elements.

     */ 

	mulwidget::TLogicalTemplate Template( ) ;

	/**

     * Set the logical template id for a specific widget element. 

     * Logical templates map to visualization of the element.

     * 

     * @param aItemIndex Unique id of item of which template needs to be applied.

     * @param aTemplateId Logical template id for the widget element.

     * @throw Invalid Argument, in case index is out of bound.

     */ 

	void SetTemplate( int aItemIndex, mulwidget::TLogicalTemplate aTemplateId, 

	                    	  const MulDataPath& aPath );

	/**

     * Returns the total number of items in model.

     */ 

	int CurrentItemCount() const;	                    	

	/**

	 * When ever data window update data window, it will use this method to notify

	 * Data model to update data window and update alf model

	 */

	virtual void DataWindowUpdated(){ };

	/**

	 * Return cachemanager 

	 * 

	 * @return cachae manager

	 */

	MulCacheManager& CacheManager() const;

	/**

	 * Get Visualte item from absolute index

	 * 

	 * @param aAbsoluteIndex Absolute index

	 * @return VisualItem at index

	 */

	virtual const MulVisualItem& Item( int aAbsoluteIndex );

	/**

	 * Check that visual item has Templatte or not

	 * If visualte item is not poper exception will be throws

	 * 

	 * @param aVisualItem Visual item to be tested

	 */

	void ValidateVisualItem( MulVisualItem& aVisualItem );

	/**

	 * Modify the data alfmodel to handle remove, insert, or expand/colapse operation

	 * 

	 * @param, aOldCount Total number of items in Alf model before the current operation

	 */	

	virtual void ModelCountChanged(int aOldCount, int aNewCount);		

private:

	/**

	 * If current highlight is greater than the number of items in model then update the highlight.

	 *

	 * @return Ture if highlight value is modified else false

	 */		

	bool ValidateCurrentHighlight();

protected: // data members	

	std::auto_ptr<MulCacheManager>	mCacheManager; //own

	MulPageDataWindow& mDataWindow;	// Not own

	//UString	 mDefaultTemplate; //default template for data	

	mulwidget::TLogicalTemplate mDefaultTemplate;

    };

    } // namespace Alf

#endif // MULPUSHMODE_H

//End of file