/********************************************************************
 KWin - the KDE window manager
 This file is part of the KDE project.

Copyright (C) 2011 Thomas Lübking <thomas.luebking@web.de>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*********************************************************************/

#include "kwinanimationeffect.h"
#include "anidata_p.h"

#include <QTime>
#include <QTimer>

namespace KWin {
struct AnimationEffectPrivate {
public:
    AnimationEffectPrivate() { m_animated = false; }
    AnimationEffect::AniMap m_animations;
    EffectWindowList m_zombies;
    bool m_animated;
};
}

using namespace KWin;

AnimationEffect::AnimationEffect() : d_ptr(new AnimationEffectPrivate())
{
    Q_D(AnimationEffect);
    d->m_animated = false;
    /* this is the same as the QTimer::singleShot(0, SLOT(init())) kludge
     * defering the init and esp. the connection to the windowClosed slot */
    QMetaObject::invokeMethod( this, "init", Qt::QueuedConnection );
}

void AnimationEffect::init()
{
    /* by connecting the signal from a slot AFTER the inheriting class constructor had the chance to
     * connect it we can provide auto-referencing of animated and closed windows, since at the time
     * our slot will be called, the slot of the subclass has been (SIGNAL/SLOT connections are FIFO)
     * and has pot. started an animation so we have the window in our hash :) */
    connect ( effects, SIGNAL(windowClosed(KWin::EffectWindow*)), SLOT(_windowClosed(KWin::EffectWindow*)) );
    connect ( effects, SIGNAL(windowDeleted(KWin::EffectWindow*)), SLOT(_windowDeleted(KWin::EffectWindow*)) );
}

bool AnimationEffect::isActive() const
{
    Q_D(const AnimationEffect);
    return !d->m_animations.isEmpty();
}


#define RELATIVE_XY(_FIELD_) const bool relative[2] = { metaData(Relative##_FIELD_##X, meta), metaData(Relative##_FIELD_##Y, meta) }

void AnimationEffect::animate( EffectWindow *w, Attribute a, uint meta, int ms, FPx2 to, QEasingCurve curve, int delay, FPx2 from )
{
    const bool waitAtSource = from.isValid();
    if (a < NonFloatBase) {
        if (a == Scale) {
            QRect area = effects->clientArea(ScreenArea , w);
            if (from.isValid()) {
                RELATIVE_XY(Source);
                from.set(   relative[0] ? from[0] * area.width() / w->width() : from[0],
                            relative[1] ? from[1] * area.height() / w->height() : from[1] );
            }
            if (to.isValid()) {
                RELATIVE_XY(Target);
                to.set( relative[0] ? to[0] * area.width() / w->width() : to[0],
                        relative[1] ? to[1] * area.height() / w->height() : to[1] );
            }
        } else if (a == Rotation) {
            if (!from.isValid()) {
                setMetaData( SourceAnchor, metaData(TargetAnchor, meta), meta );
                from.set(0.0,0.0);
            }
            if (!to.isValid()) {
                setMetaData( TargetAnchor, metaData(SourceAnchor, meta), meta );
                to.set(0.0,0.0);
            }
        }
        if (!from.isValid())
            from.set(1.0,1.0);
        if (!to.isValid())
            to.set(1.0,1.0);


    } else if (a == Position) {
        QRect area = effects->clientArea(ScreenArea , w);
        QPoint pt = w->geometry().bottomRight(); // cannot be < 0 ;-)
        if (from.isValid()) {
            RELATIVE_XY(Source);
            from.set( relative[0] ? area.x() + from[0] * area.width() : from[0],
                      relative[1] ? area.y() + from[1] * area.height() : from[1] );
        } else {
            from.set(pt.x(), pt.y());
            setMetaData( SourceAnchor, AnimationEffect::Bottom|AnimationEffect::Right, meta );
        }

        if (to.isValid()) {
            RELATIVE_XY(Target);
            to.set( relative[0] ? area.x() + to[0] * area.width() : to[0],
                    relative[1] ? area.y() + to[1] * area.height() : to[1] );
        } else {
            to.set(pt.x(), pt.y());
            setMetaData( TargetAnchor, AnimationEffect::Bottom|AnimationEffect::Right, meta );
        }


    } else if (a == Size) {
        QRect area = effects->clientArea(ScreenArea , w);
        if (from.isValid()) {
            RELATIVE_XY(Source);
            from.set( relative[0] ? from[0] * area.width() : from[0],
                      relative[1] ? from[1] * area.height() : from[1] );
        }
        else
            from.set(w->width(), w->height());

        if (to.isValid()) {
            RELATIVE_XY(Target);
            to.set( relative[0] ? to[0] * area.width() : to[0],
                    relative[1] ? to[1] * area.height() : to[1] );
        }
        else
            from.set(w->width(), w->height());


    } else if (a == Translation) {
        QRect area = w->rect();
        if (from.isValid()) {
            RELATIVE_XY(Source);
            from.set(   relative[0] ? from[0] * area.width() : from[0],
                        relative[1] ? from[1] * area.height() : from[1] );
        } else
            from.set(0.0, 0.0);

        if (to.isValid()) {
            RELATIVE_XY(Target);
            to.set( relative[0] ? to[0] * area.width() : to[0],
                    relative[1] ? to[1] * area.height() : to[1] );
        } else
            to.set(0.0, 0.0);
    }

    Q_D(AnimationEffect);
    AniMap::iterator it = d->m_animations.find(w);
    if (it == d->m_animations.end())
        it = d->m_animations.insert(w, QList<AniData>());
    it->append(AniData(a, meta, ms, to, curve, delay, from, waitAtSource));

    if (delay > 0)
        QTimer::singleShot(delay, this, SLOT(triggerRepaint()));
    else
        triggerRepaint();
}

void AnimationEffect::prePaintScreen( ScreenPrePaintData& data, int time )
{
    Q_D(AnimationEffect);
    if (d->m_animations.isEmpty()) {
        effects->prePaintScreen(data, time);
        return;
    }

    AniMap::iterator entry = d->m_animations.begin();
    d->m_animated = false;
    while (entry != d->m_animations.end()) {
        QList<AniData>::iterator anim = entry->begin();
        while (anim != entry->end()) {
            if (QTime::currentTime() < anim->startTime) {
                if (!anim->waitAtSource) {
                    ++anim;
                    continue;
                }
            } else
                anim->addTime(time);

            if (anim->time < anim->duration) {
                d->m_animated = true;
                ++anim;
            }
            else {
                animationEnded(entry.key(), anim->attribute);
                anim = entry->erase(anim);
            }
        }
        if (entry->isEmpty()) {
            const int i = d->m_zombies.indexOf(entry.key());
            if ( i > -1 ) {
                d->m_zombies.removeAt( i );
                entry.key()->unrefWindow();
            }
            entry = d->m_animations.erase(entry);
        }
        else
            ++entry;
    }

    if ( d->m_animated )
        data.mask |= PAINT_SCREEN_WITH_TRANSFORMED_WINDOWS;

    // janitorial...
    if ( !(d->m_animations.count() || d->m_zombies.isEmpty()) )
    {
        foreach ( EffectWindow *w, d->m_zombies )
            w->unrefWindow();
        d->m_zombies.clear();
    }

    effects->prePaintScreen(data, time);
}

void AnimationEffect::prePaintWindow( EffectWindow* w, WindowPrePaintData& data, int time )
{
    Q_D(AnimationEffect);
    if ( d->m_animated ) {
        AniMap::const_iterator entry = d->m_animations.constFind( w );
        if ( entry != d->m_animations.constEnd() ) {
            bool isUsed = false;
            for (QList<AniData>::const_iterator anim = entry->constBegin(); anim != entry->constEnd(); ++anim) {
                if (QTime::currentTime() < anim->startTime && !anim->waitAtSource)
                    continue;

                isUsed = true;
                if (anim->attribute == Opacity)
                    data.setTranslucent();
                else {
                    data.setTransformed();
                    data.mask |= PAINT_WINDOW_TRANSFORMED;
                }
            }
            if ( isUsed ) {
                if ( w->isMinimized() )
                    w->enablePainting( EffectWindow::PAINT_DISABLED_BY_MINIMIZE );
                else if ( w->isDeleted() )
                    w->enablePainting( EffectWindow::PAINT_DISABLED_BY_DELETE );
                else if ( !w->isOnCurrentDesktop() )
                    w->enablePainting( EffectWindow::PAINT_DISABLED_BY_DESKTOP );
                if( !w->isPaintingEnabled() && !effects->activeFullScreenEffect() )
                    w->addRepaintFull();
            }
        }
    }
    effects->prePaintWindow( w, data, time );
}

static inline float geometryCompensation(int flags, float v)
{
    if (flags & (AnimationEffect::Left|AnimationEffect::Top))
        return 0.0; // no compensation required
    if (flags & (AnimationEffect::Right|AnimationEffect::Bottom))
        return 1.0 - v; // full compensation
    return 0.5 * (1.0 - v); // half compensation
}


static int xCoord(const QRect &r, int flag) {
    if (flag & AnimationEffect::Left)
        return r.x();
    else if (flag & AnimationEffect::Right)
        return r.right();
    else
        return r.x() + r.width()/2;
}

static int yCoord(const QRect &r, int flag) {
    if (flag & AnimationEffect::Top)
        return r.y();
    else if (flag & AnimationEffect::Bottom)
        return r.bottom();
    else
        return r.y() + r.height()/2;
}

void AnimationEffect::paintWindow( EffectWindow* w, int mask, QRegion region, WindowPaintData& data )
{
    Q_D(AnimationEffect);
    if ( d->m_animated ) {
        AniMap::const_iterator entry = d->m_animations.constFind( w );
        if ( entry != d->m_animations.constEnd() ) {
            for ( QList<AniData>::const_iterator anim = entry->constBegin(); anim != entry->constEnd(); ++anim ) {

                if (QTime::currentTime() < anim->startTime && !anim->waitAtSource)
                    continue;

                switch (anim->attribute) {
                case Opacity:
                    data.opacity *= interpolated(*anim); break;
                case Brightness:
                    data.brightness *= interpolated(*anim); break;
                case Saturation:
                    data.saturation *= interpolated(*anim); break;
                case Scale: {
                    const QSize sz = w->geometry().size();
                    float f1(1.0), f2(0.0);
                    if (anim->from[0] >= 0.0 && anim->to[0] >= 0.0) { // scale x
                        f1 = interpolated(*anim, 0);
                        f2 = geometryCompensation( anim->meta & AnimationEffect::Horizontal, f1 );
                        data.xTranslate += f2 * sz.width();
                        data.xScale *= f1;
                    }
                    if (anim->from[1] >= 0.0 && anim->to[1] >= 0.0) { // scale y
                        if (!anim->isOneDimensional()) {
                            f1 = interpolated(*anim, 1);
                            f2 = geometryCompensation( anim->meta & AnimationEffect::Vertical, f1 );
                        } else if ( ((anim->meta & AnimationEffect::Vertical)>>1) != (anim->meta & AnimationEffect::Horizontal) )
                            f2 = geometryCompensation( anim->meta & AnimationEffect::Vertical, f1 );
                        data.yTranslate += f2 * sz.height();
                        data.yScale *= f1;
                    }
                    break;
                }
                case Translation:
                    data.xTranslate += interpolated(*anim, 0);
                    data.yTranslate += interpolated(*anim, 1);
                    break;
                case Size: {
                    FPx2 dest = anim->from + progress(*anim) * (anim->to - anim->from);
                    const QSize sz = w->geometry().size();
                    float f;
                    if (anim->from[0] >= 0.0 && anim->to[0] >= 0.0) { // resize x
                        f = dest[0]/sz.width();
                        data.xTranslate += geometryCompensation( anim->meta & AnimationEffect::Horizontal, f ) * sz.width();
                        data.xScale *= f;
                    }
                    if (anim->from[1] >= 0.0 && anim->to[1] >= 0.0) { // resize y
                        f = dest[1]/sz.height();
                        data.yTranslate += geometryCompensation( anim->meta & AnimationEffect::Vertical, f ) * sz.height();
                        data.yScale *= f;
                    }
                    break;
                }
                case Position: {
                    const QRect geo = w->geometry();
                    const float prgrs = progress(*anim);
                    if ( anim->from[0] >= 0.0 && anim->to[0] >= 0.0 ) {
                        float dest = interpolated(*anim, 0);
                        const int x[2] = {  xCoord(geo, metaData(SourceAnchor, anim->meta)),
                                            xCoord(geo, metaData(TargetAnchor, anim->meta)) };
                        data.xTranslate += dest - (x[0] + prgrs*(x[1] - x[0]));
                    }
                    if ( anim->from[1] >= 0.0 && anim->to[1] >= 0.0 ) {
                        float dest = interpolated(*anim, 1);
                        const int y[2] = {  yCoord(geo, metaData(SourceAnchor, anim->meta)),
                                            yCoord(geo, metaData(TargetAnchor, anim->meta)) };
                        data.yTranslate += dest - (y[0] + prgrs*(y[1] - y[0]));
                    }
                    break;
                }
                case Rotation: {
                    RotationData rot;
                    rot.axis = (RotationData::RotationAxis)metaData(Axis, anim->meta);
                    const float prgrs = progress(*anim);
                    rot.angle = anim->from[0] + prgrs*(anim->to[0] - anim->from[0]);

                    const QRect geo = w->rect();
                    const uint  sAnchor = metaData(SourceAnchor, anim->meta),
                                tAnchor = metaData(TargetAnchor, anim->meta);
                    QPointF pt(xCoord(geo, sAnchor), yCoord(geo, sAnchor));

                    if (tAnchor != sAnchor) {
                        QPointF pt2(xCoord(geo, tAnchor), yCoord(geo, tAnchor));
                        pt += static_cast<qreal>(prgrs)*(pt2 - pt);
                    }

                    rot.xRotationPoint = pt.x();
                    rot.yRotationPoint = pt.y();
                    data.rotation = &rot;
                    break;
                }
                case Generic:
                    genericAnimation(w, data, progress(*anim), anim->meta);
                    break;
                default:
                    break;
                }
            }
        }
    }
    effects->paintWindow( w, mask, region, data );
}

void AnimationEffect::postPaintScreen()
{
    Q_D(AnimationEffect);
    if ( d->m_animated )
        effects->addRepaintFull();
    effects->postPaintScreen();
}

float AnimationEffect::interpolated( const AniData &a, int i ) const
{
    if (QTime::currentTime() < a.startTime)
        return a.from[i];
    return a.from[i] + a.curve.valueForProgress( ((float)a.time)/a.duration )*(a.to[i] - a.from[i]);
}

float AnimationEffect::progress( const AniData &a ) const
{
    if (QTime::currentTime() < a.startTime)
        return 0.0;
    return a.curve.valueForProgress( ((float)a.time)/a.duration );
}


// TODO - get this out of the header - the functionpointer usage of QEasingCurve somehow sucks ;-)
// qreal AnimationEffect::qecGaussian(qreal progress) // exp(-5*(2*x-1)^2)
// {
//     progress = 2*progress - 1;
//     progress *= -5*progress;
//     return qExp(progress);
// }

int AnimationEffect::metaData( MetaType type, uint meta )
{
    switch (type) {
        case SourceAnchor:
            return ((meta>>5) & 0x1f);
        case TargetAnchor:
            return (meta& 0x1f);
        case RelativeSourceX:
        case RelativeSourceY:
        case RelativeTargetX:
        case RelativeTargetY: {
            const int shift = 10 + type - RelativeSourceX;
            return ((meta>>shift) & 1);
        }
        case Axis:
            return ((meta>>10) & 3);
        default:
            return 0;
    }
}

void AnimationEffect::setMetaData( MetaType type, uint value, uint &meta )
{
    switch (type) {
    case SourceAnchor:
        meta &= ~(0x1f<<5);
        meta |= ((value & 0x1f)<<5);
        break;
    case TargetAnchor:
        meta &= ~(0x1f);
        meta |= (value & 0x1f);
        break;
    case RelativeSourceX:
    case RelativeSourceY:
    case RelativeTargetX:
    case RelativeTargetY: {
        const int shift = 10 + type - RelativeSourceX;
        if (value)
            meta |= (1<<shift);
        else
            meta &= ~(1<<shift);
        break;
    }
    case Axis:
        meta &= ~(3<<10);
        meta |= ((value & 3)<<10);
        break;
    default:
        break;
    }
}

void AnimationEffect::triggerRepaint()
{
    Q_D(AnimationEffect);
    if (!d->m_animated)
        effects->addRepaintFull();
}


void AnimationEffect::_windowClosed( EffectWindow* w )
{
    Q_D(AnimationEffect);
    if (d->m_animations.contains(w) && !d->m_zombies.contains(w)) {
        w->refWindow();
        d->m_zombies << w;
    }
}

void AnimationEffect::_windowDeleted( EffectWindow* w )
{
    Q_D(AnimationEffect);
    d->m_animations.remove( w );
}


#include "moc_kwinanimationeffect.cpp"