/* This file is part of the KDE project
 * SPDX-FileCopyrightText: 2008 Jan Hambrecht <jaham@gmx.net>
 *
 * SPDX-License-Identifier: LGPL-2.0-or-later
 */

#include "DoubleBarnDoorWipeStrategy.h"
#include "MiscDiagonalWipeEffectFactory.h"
#include <QWidget>
#include <QPainter>
#include <QPainterPath>

const int StepCount = 250;

DoubleBarnDoorWipeStrategy::DoubleBarnDoorWipeStrategy()
    : KPrPageEffectStrategy( MiscDiagonalWipeEffectFactory::DoubleBarnDoor, "miscDiagonalWipe", "doubleBarnDoor", false )
{
}

DoubleBarnDoorWipeStrategy::~DoubleBarnDoorWipeStrategy()
{
}

void DoubleBarnDoorWipeStrategy::setup( const KPrPageEffect::Data &data, QTimeLine &timeLine )
{
    Q_UNUSED( data );
    timeLine.setFrameRange( 0, StepCount );
}

void DoubleBarnDoorWipeStrategy::paintStep( QPainter &p, int currPos, const KPrPageEffect::Data &data )
{
    p.drawPixmap( QPoint( 0, 0 ), data.m_oldPage, data.m_widget->rect() );
    p.setClipPath( clipPath( currPos, data.m_widget->rect() ) );
    p.drawPixmap( QPoint( 0, 0 ), data.m_newPage, data.m_widget->rect() );
}

void DoubleBarnDoorWipeStrategy::next( const KPrPageEffect::Data &data )
{
    data.m_widget->update();
}

QPainterPath DoubleBarnDoorWipeStrategy::clipPath( int step, const QRect &area )
{
    int width_2 = area.width() >> 1;
    int height_2 = area.height() >> 1;

    qreal percent = static_cast<qreal>( step ) / static_cast<qreal>( StepCount );
    int stepx = static_cast<int>( width_2 * percent );
    int stepy = static_cast<int>( height_2 * percent );

    QPainterPath path;
    path.lineTo( area.topLeft() );
    path.lineTo( area.topLeft() + QPoint( stepx, 0 ) );
    path.lineTo( area.center() - QPoint( 0, stepy ) );
    path.lineTo( area.topRight() - QPoint( stepx, 0 ) );
    path.lineTo( area.topRight() );
    path.lineTo( area.topRight() + QPoint( 0, stepy ) );
    path.lineTo( area.center() + QPoint( stepx, 0 ) );
    path.lineTo( area.bottomRight() - QPoint( 0, stepy ) );
    path.lineTo( area.bottomRight() );
    path.lineTo( area.bottomRight() - QPoint( stepx, 0 ) );
    path.lineTo( area.center() + QPoint( 0, stepy ) );
    path.lineTo( area.bottomLeft() + QPoint( stepx, 0 ) );
    path.lineTo( area.bottomLeft() );
    path.lineTo( area.bottomLeft() - QPoint( 0, stepy ) );
    path.lineTo( area.center() - QPoint( stepx, 0 ) );
    path.lineTo( area.topLeft() + QPoint( 0, stepy ) );
    path.closeSubpath();

    return path;
}
