/****************************************************************************
**
** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of Qt Creator.
**
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia.  For licensing terms and
** conditions see http://qt.digia.com/licensing.  For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Digia gives you certain additional
** rights.  These rights are described in the Digia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
****************************************************************************/

#ifndef STYLEANIMATOR_H
#define STYLEANIMATOR_H

#include <QPointer>
#include <QTime>
#include <QBasicTimer>
#include <QStyle>
#include <QPainter>
#include <QWidget>

/*
 * This is a set of helper classes to allow for widget animations in
 * the style. Its mostly taken from Vista style so it should be fully documented
 * there.
 *
 */

class Animation
{
public :
    Animation() : m_running(true) { }
    virtual ~Animation() { }
    QWidget * widget() const { return m_widget; }
    bool running() const { return m_running; }
    const QTime &startTime() const { return m_startTime; }
    void setRunning(bool val) { m_running = val; }
    void setWidget(QWidget *widget) { m_widget = widget; }
    void setStartTime(const QTime &startTime) { m_startTime = startTime; }
    virtual void paint(QPainter *painter, const QStyleOption *option);

protected:
    void drawBlendedImage(QPainter *painter, QRect rect, float value);
    QTime m_startTime;
    QPointer<QWidget> m_widget;
    QImage m_primaryImage;
    QImage m_secondaryImage;
    QImage m_tempImage;
    bool m_running;
};

// Handles state transition animations
class Transition : public Animation
{
public :
    Transition() : Animation(), m_duration(100) {}
    virtual ~Transition() {}
    void setDuration(int duration) { m_duration = duration; }
    void setStartImage(const QImage &image) { m_primaryImage = image; }
    void setEndImage(const QImage &image) { m_secondaryImage = image; }
    virtual void paint(QPainter *painter, const QStyleOption *option);
    int duration() const { return m_duration; }
    int m_duration; //set time in ms to complete a state transition
};

class StyleAnimator : public QObject
{
    Q_OBJECT

public:
    StyleAnimator(QObject *parent = 0) : QObject(parent) {}

    void timerEvent(QTimerEvent *);
    void startAnimation(Animation *);
    void stopAnimation(const QWidget *);
    Animation* widgetAnimation(const QWidget *) const;

private:
    QBasicTimer animationTimer;
    QList <Animation*> animations;
};

#endif // STYLEANIMATOR_H
