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

Copyright (C) 2007 Philip Falkner <philip.falkner@gmail.com>
Copyright (C) 2009 Martin Gräßlin <mgraesslin@kde.org>
Copyright (C) 2010 Alexandre Pereira <pereira.alex@gmail.com>

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 "glide.h"
// KConfigSkeleton
#include "glideconfig.h"

#include <QTimeLine>

// Effect is based on fade effect by Philip Falkner

namespace KWin
{

static const int IsGlideWindow = 0x22A982D4;

GlideEffect::GlideEffect()
    : Effect()
{
    initConfig<GlideConfig>();
    reconfigure(ReconfigureAll);
    connect(effects, SIGNAL(windowAdded(KWin::EffectWindow*)), this, SLOT(slotWindowAdded(KWin::EffectWindow*)));
    connect(effects, SIGNAL(windowClosed(KWin::EffectWindow*)), this, SLOT(slotWindowClosed(KWin::EffectWindow*)));
    connect(effects, SIGNAL(windowDeleted(KWin::EffectWindow*)), this, SLOT(slotWindowDeleted(KWin::EffectWindow*)));


    connect(effects, &EffectsHandler::windowDataChanged, this, &GlideEffect::cancelWindowGrab);
}

GlideEffect::~GlideEffect() = default;

bool GlideEffect::supported()
{
    return effects->isOpenGLCompositing() && effects->animationsSupported();
}

void GlideEffect::reconfigure(ReconfigureFlags)
{
    // Fetch config with KConfigXT
    GlideConfig::self()->read();
    duration = animationTime<GlideConfig>(350);
    effect = (EffectStyle) GlideConfig::glideEffect();
    angle = GlideConfig::glideAngle();
}

void GlideEffect::prePaintScreen(ScreenPrePaintData& data, int time)
{
    if (!windows.isEmpty())
        data.mask |= PAINT_SCREEN_WITH_TRANSFORMED_WINDOWS;
    effects->prePaintScreen(data, time);
}

void GlideEffect::prePaintWindow(EffectWindow* w, WindowPrePaintData& data, int time)
{
    InfoHash::iterator info = windows.find(w);
    if (info != windows.end()) {
        data.setTransformed();
        if (info->added)
            info->timeLine->setCurrentTime(info->timeLine->currentTime() + time);
        else if (info->closed) {
            info->timeLine->setCurrentTime(info->timeLine->currentTime() - time);
            if (info->deleted)
                w->enablePainting(EffectWindow::PAINT_DISABLED_BY_DELETE);
        }
    }

    effects->prePaintWindow(w, data, time);

    // if the window isn't to be painted, then let's make sure
    // to track its progress
    if (info != windows.end() && !w->isPaintingEnabled() && !effects->activeFullScreenEffect())
        w->addRepaintFull();
}

void GlideEffect::paintWindow(EffectWindow* w, int mask, QRegion region, WindowPaintData& data)
{
    InfoHash::const_iterator info = windows.constFind(w);
    if (info != windows.constEnd()) {
        const double progress = info->timeLine->currentValue();
        data.setRotationAxis(Qt::XAxis);
        data.setRotationAngle(angle * (1 - progress));
        data.multiplyOpacity(progress);
        switch(effect) {
        default:
        case GlideInOut:
            if (info->added)
                glideIn(w, data, info);
            else if (info->closed)
                glideOut(w, data, info);
            break;
        case GlideOutIn:
            if (info->added)
                glideOut(w, data, info);
            if (info->closed)
                glideIn(w, data, info);
            break;
        case GlideIn: glideIn(w, data, info); break;
        case GlideOut: glideOut(w, data, info); break;
        }
    }
    effects->paintWindow(w, mask, region, data);
}

void GlideEffect::glideIn(EffectWindow* w, WindowPaintData& data, const InfoHash::const_iterator &info)
{
    const double progress = info->timeLine->currentValue();
    data *= progress;
    data.translate(int(w->width() / 2 * (1 - progress)), int(w->height() / 2 * (1 - progress)));
}

void GlideEffect::glideOut(EffectWindow* w, WindowPaintData& data, const InfoHash::const_iterator &info)
{
    const double progress = info->timeLine->currentValue();
    data *= (2 - progress);
    data.translate(- int(w->width() / 2 * (1 - progress)), - int(w->height() / 2 * (1 - progress)));
}

void GlideEffect::postPaintWindow(EffectWindow* w)
{
    InfoHash::iterator info = windows.find(w);
    if (info != windows.end()) {
        if (info->added && info->timeLine->currentValue() == 1.0) {
            windows.remove(w);
            effects->addRepaintFull();
        } else if (info->closed && info->timeLine->currentValue() == 0.0) {
            info->closed = false;
            if (info->deleted) {
                windows.remove(w);
                w->unrefWindow();
            }
            effects->addRepaintFull();
        }
        if (info->added || info->closed)
            w->addRepaintFull();
    }
    effects->postPaintWindow(w);
}

void GlideEffect::slotWindowAdded(EffectWindow* w)
{
    if (!isGlideWindow(w))
        return;
    w->setData(IsGlideWindow, true);
    const void *addGrab = w->data(WindowAddedGrabRole).value<void*>();
    if (addGrab && addGrab != this)
        return;
    w->setData(WindowAddedGrabRole, QVariant::fromValue(static_cast<void*>(this)));

    InfoHash::iterator it = windows.find(w);
    WindowInfo *info = (it == windows.end()) ? &windows[w] : &it.value();
    info->added = true;
    info->closed = false;
    info->deleted = false;
    delete info->timeLine;
    info->timeLine = new QTimeLine(duration);
    info->timeLine->setCurveShape(QTimeLine::EaseOutCurve);
    w->addRepaintFull();
}

void GlideEffect::slotWindowClosed(EffectWindow* w)
{
    if (!isGlideWindow(w))
        return;
    const void *closeGrab = w->data(WindowClosedGrabRole).value<void*>();
    if (closeGrab && closeGrab != this)
        return;
    w->refWindow();
    w->setData(WindowClosedGrabRole, QVariant::fromValue(static_cast<void*>(this)));

    InfoHash::iterator it = windows.find(w);
    WindowInfo *info = (it == windows.end()) ? &windows[w] : &it.value();
    info->added = false;
    info->closed = true;
    info->deleted = true;
    delete info->timeLine;
    info->timeLine = new QTimeLine(duration);
    info->timeLine->setCurveShape(QTimeLine::EaseInCurve);
    info->timeLine->setCurrentTime(info->timeLine->duration());
    w->addRepaintFull();
}

void GlideEffect::slotWindowDeleted(EffectWindow* w)
{
    windows.remove(w);
}

bool GlideEffect::isGlideWindow(EffectWindow* w)
{
    if (effects->activeFullScreenEffect())
        return false;
    if (!w->isVisible())
        return false;
    if (w->data(IsGlideWindow).toBool())
        return true;
    if (w->hasDecoration())
        return true;
    if (!w->isManaged() || w->isMenu() ||  w->isNotification() || w->isDesktop() ||
            w->isDock() ||  w->isSplash() || w->isToolbar())
        return false;
    return true;
}

bool GlideEffect::isActive() const
{
    return !windows.isEmpty();
}

void GlideEffect::cancelWindowGrab(EffectWindow *w, int grabRole)
{
    if (grabRole != WindowAddedGrabRole && grabRole != WindowClosedGrabRole) {
        return;
    }
    if (!w->data(IsGlideWindow).toBool()) {
        return;
    }
    if (w->data(grabRole).value<void*>() != this) {
        windows.remove(w);
        w->setData(IsGlideWindow, false);
    }
}

GlideEffect::WindowInfo::WindowInfo()
    : deleted(false)
    , added(false)
    , closed(false)
    , timeLine(0)
{
}

GlideEffect::WindowInfo::~WindowInfo()
{
    delete timeLine;
}

} // namespace