/*
* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
* All rights reserved.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, version 2.1 of the License.
* 
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program.  If not, 
* see "http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html/".
*
* Description:
*
*/


#ifndef __FLOWBASE_H__
#define __FLOWBASE_H__

#include <QImage>
#include <QWidget>
#include <QGraphicsWidget>
#include <QGraphicsItem>

class QPainter;
#include "BWFGlobal.h"


namespace WRT {
    /*!
     * \class FlowInterface
     *
     * \brief This file describes the common interface of the various history view engines
     * i.e., PictureFlow, VisualFlow
     *
     * This class is designed so that the Views using these engines can implement some functionality
     * in common modules, and assign the specific engine at a higher level
     */
    class BWF_EXPORT FlowInterfaceBase
    {
    public:
        //! Perform init steps on flow
        virtual void init() = 0;

        //! Clear all slides
        virtual void clear() = 0;
        
        //! Add a slide to the flow
        virtual void addSlide(const QImage& image) = 0;

        //! Add a slide to the flow
        virtual void addSlide(const QImage&, const QString&) {};

        //! Set the center of the flow
        virtual void setCenterIndex(int i) = 0;

        //! Show the previous item 
        virtual void showPrevious() = 0;

        //! Show the next item
        virtual void showNext() = 0;

        //! Returns the total number of slides.
        virtual int slideCount() const = 0;

        //! Returns QImage of specified slide.
        virtual QImage slide(int) const = 0;

        //! Return the index of the current center slide
        virtual int centerIndex() const = 0;

        //! Return true if slide animation is ongoing
        virtual bool slideAnimationOngoing() const = 0;

        //! Return the central slide's rect
        virtual QRect centralRect() const = 0;

        //! Insert a slide at index position
        virtual void insert(int, const QImage&, const QString&) {}

        //! Remove a slide at index position
        virtual void removeAt(int) {}

        //! handle the display mode change
        virtual void displayModeChanged(QString&) {}

        //! handle the display mode change
        virtual void displayModeChanged(QSize) {}

        //! prepare start-animation
        virtual void prepareStartAnimation() {}

        //! run start-animation
        virtual void runStartAnimation() {}
        
        //! run end-animation
        virtual void runEndAnimation() {}
    };

    class BWF_EXPORT FlowInterface : public QWidget, public FlowInterfaceBase
    {
        Q_OBJECT
    public:
        //! Init the FlowInterface with a QWidget parent
        FlowInterface(QWidget* parent) : QWidget(parent) {}

        //! declear common signals
    signals:
        void centerIndexChanged(int index);
        void ok(int index);
        void cancel();
    };

    class BWF_EXPORT GraphicsFlowInterface : public QGraphicsWidget, public FlowInterfaceBase
    {
        Q_OBJECT
    public:
        //! Init the FlowInterface with a QWidget parent
        GraphicsFlowInterface(QGraphicsItem* parent);
        bool event(QEvent* event);
        
    signals:
        void centerIndexChanged(int index);
        void ok(int index);
        void cancel();
    };
}

#endif      // __FLOWBASE_H__