/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Qt Software Information (qt-info@nokia.com)
**
** This file is part of the QtDeclarative module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the either Technology Preview License Agreement or the
** Beta Release License Agreement.
**
** 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, Nokia gives you certain
** additional rights. These rights are described in the Nokia Qt LGPL
** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
** package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at qt-sales@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qfxpixmap.h"
#include <QHash>
#include <QNetworkReply>
#include <qfxperf.h>
#include <QtDeclarative/qmlengine.h>
#include <QFile>


QT_BEGIN_NAMESPACE
class QFxPixmapCacheItem;
typedef QHash<QString, QFxPixmapCacheItem *> QFxPixmapCache;
static QFxPixmapCache qfxPixmapCache;

class QFxPixmapCacheItem
{
public:
    QFxPixmapCacheItem() : reply(0), refCount(1) {}
    QString key;
    QNetworkReply *reply;
#if defined(QFX_RENDER_OPENGL)
    QImage image;
#else
    QImage image;
    QImage opaqueImage;
#endif

    int refCount;
    void addRef() { ++refCount; }
    void release() { Q_ASSERT(refCount > 0); --refCount; if (refCount == 0) { qfxPixmapCache.remove(key); delete this; } }
};

static QFxPixmapCacheItem qfxPixmapCacheDummyItem;

class QFxPixmapPrivate
{
public:
    QFxPixmapPrivate()
    : opaque(false), pixmap(&qfxPixmapCacheDummyItem) { pixmap->addRef(); }

    bool opaque;
    QFxPixmapCacheItem *pixmap;
};

/*!
    \internal
    \class QFxPixmap
    \ingroup group_utility
    \brief Enacapsultes a pixmap for QFx items.

    This class is NOT reentrant.
    The pixmap cache will grow indefinately.
 */
QFxPixmap::QFxPixmap()
: d(new QFxPixmapPrivate)
{
}

QFxPixmap::QFxPixmap(const QUrl &url)
: d(new QFxPixmapPrivate)
{
#ifdef Q_ENABLE_PERFORMANCE_LOG
    QFxPerfTimer<QFxPerf::PixmapLoad> perf;
#endif
    QString key = url.toString();
    QFxPixmapCache::Iterator iter = qfxPixmapCache.find(key);
    if (iter == qfxPixmapCache.end()) {
        qWarning() << "QFxPixmap: URL not loaded" << url;
    } else {
        QNetworkReply *reply = (*iter)->reply;
        if (reply) {
            if (reply->error()) {
                qWarning() << "Error loading" << url << reply->errorString();
            } else {
                (*iter)->image.load(reply, 0);
            }
            reply->deleteLater();
            (*iter)->reply = 0;
        }
        (*iter)->addRef();
    }

    d->pixmap = *iter;
}

QFxPixmap::QFxPixmap(const QFxPixmap &o)
: d(new QFxPixmapPrivate)
{
    d->opaque = o.d->opaque;
    o.d->pixmap->addRef();
    d->pixmap->release();
    d->pixmap = o.d->pixmap;
}

QFxPixmap::~QFxPixmap()
{
    d->pixmap->release();
    delete d;
}

QFxPixmap &QFxPixmap::operator=(const QFxPixmap &o)
{
    d->opaque = o.d->opaque;
    o.d->pixmap->addRef();
    d->pixmap->release();
    d->pixmap = o.d->pixmap;
    return *this;
}

bool QFxPixmap::isNull() const
{
    return d->pixmap->image.isNull();
}

bool QFxPixmap::opaque() const
{
    return d->opaque;
}

void QFxPixmap::setOpaque(bool o)
{
    d->opaque = o;
}

int QFxPixmap::width() const
{
    return d->pixmap->image.width();
}

int QFxPixmap::height() const
{
    return d->pixmap->image.height();
}

QPixmap QFxPixmap::pixmap() const
{
    return QPixmap::fromImage(d->pixmap->image);
}

void QFxPixmap::setPixmap(const QPixmap &pix)
{
    QFxPixmapCache::Iterator iter = qfxPixmapCache.find(QString::number(pix.cacheKey()));
    if (iter == qfxPixmapCache.end()) {
        QFxPixmapCacheItem *item = new QFxPixmapCacheItem;
        item->key = QString::number(pix.cacheKey());
        if (d->pixmap)
            d->pixmap->release();
        d->pixmap = item;
        d->pixmap->image = pix.toImage();
        qfxPixmapCache.insert(QString::number(pix.cacheKey()), item);
    } else {
        (*iter)->addRef();
        d->pixmap = *iter;
    }

#if 0
    int size = 0;
    for (QFxPixmapCache::Iterator iter = qfxPixmapCache.begin(); iter != qfxPixmapCache.end(); ++iter) {
        size += (*iter)->image.width() * (*iter)->image.height();
    }
    qWarning() << qfxPixmapCache.count() << size;
#endif
}

QFxPixmap::operator const QSimpleCanvasConfig::Image &() const
{
#if defined(QFX_RENDER_OPENGL)
    return d->pixmap->image;
#else
    if (d->opaque) {
        if (!d->pixmap->image.isNull() && d->pixmap->opaqueImage.isNull()) {
#ifdef Q_ENABLE_PERFORMANCE_LOG
            QFxPerfTimer<QFxPerf::PixmapLoad> perf;
#endif
            d->pixmap->opaqueImage = d->pixmap->image.convertToFormat(QPixmap::defaultDepth() == 16 ?
                                                                      QImage::Format_RGB16 :
                                                                      QImage::Format_RGB32);
        }
        return d->pixmap->opaqueImage;
    } else {
        if (!d->pixmap->image.isNull() && d->pixmap->image.format() != QImage::Format_ARGB32_Premultiplied) {
#ifdef Q_ENABLE_PERFORMANCE_LOG
            QFxPerfTimer<QFxPerf::PixmapLoad> perf;
#endif
            d->pixmap->image = d->pixmap->image.convertToFormat(QImage::Format_ARGB32_Premultiplied);
        }
        return d->pixmap->image;
    }
#endif
}

/*!
    Starts a network request to load \a url. When the URL is loaded,
    the given slot is invoked. Note that if the image is already cached,
    the slot may be invoked immediately.

    Returns a QNetworkReply if the image is not immediately available, otherwise
    returns 0.  The QNetworkReply must not be stored - it may be destroyed at any time.
*/
QNetworkReply *QFxPixmap::get(QmlEngine *engine, const QUrl& url, QObject* obj, const char* slot)
{
    QString key = url.toString();
    QFxPixmapCache::Iterator iter = qfxPixmapCache.find(key);
    if (iter == qfxPixmapCache.end()) {
        QFxPixmapCacheItem *item = new QFxPixmapCacheItem;
        item->addRef(); // XXX - will never get deleted.  Need to revisit caching
        item->key = key;
#ifndef QT_NO_LOCALFILE_OPTIMIZED_QML
        if (url.scheme()==QLatin1String("file")) {
            item->image.load(url.toLocalFile(), 0);
        } else
#endif
        {
            QNetworkRequest req(url);
            req.setAttribute(QNetworkRequest::CacheLoadControlAttribute, QNetworkRequest::PreferCache);
            item->reply = engine->networkAccessManager()->get(req);
        }
        iter = qfxPixmapCache.insert(item->key, item);
    } else {
        (*iter)->addRef();
    }
    if ((*iter)->reply) {
        // still loading
        QObject::connect((*iter)->reply, SIGNAL(finished()), obj, slot);
        return (*iter)->reply;
    } else {
        // already loaded
        QObject dummy;
        QObject::connect(&dummy, SIGNAL(destroyed()), obj, slot);
    }

    return 0;
}

/*!
    Stops the given slot being invoked if the given url finishes loading.
    May also cancel loading (eg. if no other pending request).

    Any connections to the QNetworkReply returned by get() will be
    disconnected.
*/
void QFxPixmap::cancelGet(const QUrl& url, QObject* obj)
{
    QString key = url.toString();
    QFxPixmapCache::Iterator iter = qfxPixmapCache.find(key);
    if (iter == qfxPixmapCache.end())
        return;
    if ((*iter)->reply)
        QObject::disconnect((*iter)->reply, 0, obj, 0);
    // XXX - loading not cancelled. Need to revisit caching
}

QT_END_NAMESPACE