/*

* Copyright (c) 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:

*

*/

#ifndef HGDATAPROVIDERMODEL_H_

#define HGDATAPROVIDERMODEL_H_

#include <QObject>

#include <QList>

#include <QPair>

#include <QPixmap>

#include <QMap>

#include <QMutex>

#include <QAbstractItemModel>

class HbIcon;

class QVariant;

class HgCacheProxyModel;

#ifdef BUILD_CACHEPROXYMODEL

#define CACHEPROXYMODEL_EXPORT Q_DECL_EXPORT

#else

#define CACHEPROXYMODEL_EXPORT Q_DECL_IMPORT

#endif

class HgDataProviderModelObserver

{

public:

    virtual void dataUpdated(int from, int to) = 0;    

};

class CACHEPROXYMODEL_EXPORT HgDataProviderModel : public QAbstractItemModel

{

    Q_OBJECT

public:

    HgDataProviderModel(QObject *parent = 0);

    ~HgDataProviderModel();   

//to cooperate with buffer manager    

    void release(QList<int> list, bool silent = true);

    void request(QList<int> list, bool silent = false);  

    virtual void doReleaseData(QList<int> list, bool silent) = 0;

    virtual void doRequestData(QList<int> list, bool silent) = 0;  

    void registerObserver(HgDataProviderModelObserver* obs);

public:

//from QAbstractItemModel

    QModelIndex index(int row, int column,

                              const QModelIndex &parent = QModelIndex()) const;

    virtual QModelIndex parent(const QModelIndex &child) const;

    virtual int rowCount(const QModelIndex &parent = QModelIndex()) const;

    virtual int columnCount(const QModelIndex &parent = QModelIndex()) const;

    virtual QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const;

    virtual QMap<int, QVariant> itemData(const QModelIndex &index) const;

//cache management    

protected:

    QVariant data(int idx, int role) const;

    void clearCache();

    int count() const;

    bool update(int pos, QVariant obj, int role, bool silent = false);

    bool update(int pos, QList< QPair< QVariant, int > >* list, bool silent = false);    

    bool updateIcon(int pos, QVariant obj, bool silent = false);

    void resetIcon(int idx);

    void newItem(QList< QPair< QVariant, int > >* list = NULL, bool silent = true);

    void newItem(QPair< QVariant, int > item, bool silent = true);

    void insertItem(int pos, QList< QPair< QVariant, int > >* list = NULL, bool silent = true);

    void insertItem(int pos, QPair< QVariant, int > item, bool silent = true);

private:

    void doInsertItem(int pos, QList< QPair< QVariant, int > >* list, bool silent);

protected:

    virtual QVariant defaultIcon() const = 0;

    inline bool containsRole(int idx, int role) const;

    inline bool isIndexValid(int idx) const;

public:    

    void resetModel();

protected:    

    virtual void doResetModel() {};

// helpers fot emits

protected:  

    void emitDataChanged(int start, int end, bool silent);

//QPixmap pool

public:

    void resizeQPixmapPool(int size);

protected:  

    void releasePixmap(int idx);

    QVariant createIcon(int index, QPixmap aPixmap);

private:

    QPixmap* getPixmap(int idx);

private:

    QList<QMap<int, QVariant>*>* mCache;   

    int mCacheSize; //Number of cached Icons. Not same as mCache->count()

    QList< QPixmap* > mFreePixmaps;

    QMap< int, QPixmap* > mUsedPixmaps;    

    int mUnallocatedPixmaps;

    QMutex mQPixmapsLock;

    QMutex mDataLock;    

    HgDataProviderModelObserver *mObserver;

};

inline bool HgDataProviderModel::isIndexValid(int idx) const

{

    return ((idx >= 0) && 

            (idx < mCache->size()) && 

            (mCache->at(idx))); 

}

inline bool HgDataProviderModel::containsRole(int idx, int role) const

{

    return ( isIndexValid(idx) && 

             mCache->at(idx)->contains(role) ); 

}

#endif // HGDATAPROVIDERMODEL_H_