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#include "qdeclarativegalleryitem.h"

#include <qgalleryresultset.h>

#include <QtCore/qcoreapplication.h>
#include <QtDeclarative/qdeclarativeinfo.h>
#include <QtDeclarative/qdeclarativepropertymap.h>

QTM_BEGIN_NAMESPACE

QDeclarativeGalleryItem::QDeclarativeGalleryItem(QObject *parent)
    : QObject(parent)
    , m_metaData(0)
    , m_status(Null)
    , m_updateStatus(Incomplete)
{
    connect(&m_request, SIGNAL(stateChanged(QGalleryAbstractRequest::State)),
            this, SLOT(_q_stateChanged()));
    connect(&m_request, SIGNAL(progressChanged(int,int)), this, SIGNAL(progressChanged()));

    connect(&m_request, SIGNAL(itemChanged()),
            this, SLOT(_q_itemChanged()));
    connect(&m_request, SIGNAL(metaDataChanged(QList<int>)),
            this, SLOT(_q_metaDataChanged(QList<int>)));

    m_metaData = new QDeclarativePropertyMap(this);

    connect(m_metaData, SIGNAL(valueChanged(QString,QVariant)),
            this, SLOT(_q_valueChanged(QString,QVariant)));
}

QDeclarativeGalleryItem::~QDeclarativeGalleryItem()
{
}

qreal QDeclarativeGalleryItem::progress() const
{
    const int max = m_request.maximumProgress();

    return max > 0
            ? qreal(m_request.currentProgress()) / max
            : qreal(0.0);
}

void QDeclarativeGalleryItem::setPropertyNames(const QStringList &names)
{
    if (m_updateStatus == Incomplete) {
        m_request.setPropertyNames(names);

        emit propertyNamesChanged();
    }
}

void QDeclarativeGalleryItem::setAutoUpdate(bool enabled)
{
    if (m_request.autoUpdate() != enabled) {
        m_request.setAutoUpdate(enabled);

        if (enabled)
            deferredExecute();
        else if (m_status == Idle)
            m_request.cancel();

        emit autoUpdateChanged();
    }
}

void QDeclarativeGalleryItem::setItemId(const QVariant &itemId)
{
    if (m_request.itemId() != itemId) {
        m_request.setItemId(itemId);

        if (m_updateStatus != Incomplete) {
            if (itemId.isValid())
                m_request.execute();
            else
                m_request.clear();
        }

        emit itemIdChanged();
    }
}

void QDeclarativeGalleryItem::componentComplete()
{
    m_updateStatus = NoUpdate;

    if (m_request.itemId().isValid())
        m_request.execute();
}

void QDeclarativeGalleryItem::reload()
{
    if (m_updateStatus == PendingUpdate)
        m_updateStatus = CanceledUpdate;

    m_request.execute();
}

void QDeclarativeGalleryItem::cancel()
{
    if (m_updateStatus == PendingUpdate)
        m_updateStatus = CanceledUpdate;

    m_request.cancel();
}

void QDeclarativeGalleryItem::clear()
{
    if (m_updateStatus == PendingUpdate)
        m_updateStatus = CanceledUpdate;

    m_request.clear();
}

void QDeclarativeGalleryItem::deferredExecute()
{
    if (m_updateStatus == NoUpdate) {
        m_updateStatus = PendingUpdate;

        QCoreApplication::postEvent(this, new QEvent(QEvent::UpdateRequest));
    } else if (m_updateStatus == CanceledUpdate) {
        m_updateStatus = PendingUpdate;
    }
}

bool QDeclarativeGalleryItem::event(QEvent *event)
{
    if (event->type() == QEvent::UpdateRequest) {
        UpdateStatus status = m_updateStatus;
        m_updateStatus = NoUpdate;

        if (status == PendingUpdate)
            m_request.execute();

        return true;
    } else {
        return QObject::event(event);
    }
}

void QDeclarativeGalleryItem::_q_stateChanged()
{
    m_status = Status(m_request.state());

    if (m_status == Error) {
        const QString message = m_request.errorString();

        if (!message.isEmpty()) {
            qmlInfo(this) << message;
        } else {
            switch (m_request.error()) {
            case QDocumentGallery::ConnectionError:
                qmlInfo(this) << tr("An error was encountered connecting to the document gallery");
                break;
            case QDocumentGallery::ItemIdError:
                qmlInfo(this) << tr("The value of item is not a valid item ID");
                break;
            default:
                break;
            }
        }
        emit statusChanged();
    } else if (m_status == Idle && !m_request.autoUpdate()) {
        m_request.cancel();
    } else {
        emit statusChanged();
    }
}

void QDeclarativeGalleryItem::_q_itemChanged()
{
    if (m_request.isValid()) {
        for (QHash<int, QString>::const_iterator it = m_propertyKeys.constBegin();
                it != m_propertyKeys.constEnd();
                ++it) {
            if (m_request.propertyKey(it.value()) < 0)
                m_metaData->clear(it.value());
        }

        m_propertyKeys.clear();

        const QStringList propertyNames = m_request.propertyNames();

        for (QStringList::const_iterator it = propertyNames.begin(); it != propertyNames.end(); ++it) {
            const int key = m_request.propertyKey(*it);

            if (key >= 0) {
                m_propertyKeys.insert(key, *it);

                QVariant value = m_request.metaData(key);
                m_metaData->insert(*it, value.isNull()
                        ? QVariant(m_request.propertyType(key))
                        : value);
            }
        }
    } else {
        typedef QHash<int, QString>::const_iterator iterator;
        for (iterator it = m_propertyKeys.constBegin(); it != m_propertyKeys.constEnd(); ++it)
            m_metaData->clear(it.value());

        m_propertyKeys.clear();
    }

    emit availableChanged();
}

void QDeclarativeGalleryItem::_q_metaDataChanged(const QList<int> &keys)
{
    typedef QList<int>::const_iterator iterator;
    for (iterator it = keys.begin(); it != keys.end(); ++it){
        QVariant value = m_request.metaData(*it);
        m_metaData->insert(m_propertyKeys.value(*it), value.isNull()
                ? QVariant(m_request.propertyType(*it))
                : value);
    }
}

/*!
    \qmlclass DocumentGalleryItem QDeclarativeDocumentGalleryItem

    \inmodule QtGallery
    \ingroup qml-gallery

    \brief The DocumentGalleryItem element allows you to request information
    about a single item from the document gallery

    This element is part of the \bold {QtMobility.gallery 1.1} module.


    \sa DocumentGalleryModel, DocumentGalleryType
*/

QDeclarativeDocumentGalleryItem::QDeclarativeDocumentGalleryItem(QObject *parent)
    : QDeclarativeGalleryItem(parent)
{
    connect(this, SIGNAL(availableChanged()), this, SIGNAL(itemTypeChanged()));
}

QDeclarativeDocumentGalleryItem::~QDeclarativeDocumentGalleryItem()
{
}

void QDeclarativeDocumentGalleryItem::classBegin()
{
    m_request.setGallery(QDeclarativeDocumentGallery::gallery(this));
}

/*!
    \qmlproperty enum DocumentGalleryItem::status

    This property holds the status of an item request.  It can be one of:

    \list
    \o Null No \l item has been specified.
    \o Active Information about an \l item is being fetched from the gallery.
    \o Finished Information about an \l item is available.
    \o Idle Information about an \l item which will be automatically
    updated is available.
    \o Canceling The query was canceled but hasn't yet reached the
    canceled status.
    \o Canceled The query was canceled.
    \o Error Information about a type could not be retrieved due to an error.
    \endlist
*/

/*!
    \qmlproperty real DocumentGalleryItem::progress

    This property holds the current progress of the request, from 0.0 (started)
    to 1.0 (finished).
*/

/*!
    \qmlproperty QStringList DocumentGalleryItem::properties

    This property holds the item properties a request should return values for.
*/

/*!
    \qmlproperty bool DocumentGalleryItem::autoUpdate

    This property holds whether a request should refresh its results
    automatically.
*/

/*!
    \qmlproperty variant DocumentGalleryItem::item

    This property holds the id of the item to return information about.
*/

/*!
    \qmlproperty bool DocumentGalleryItem::available

    This property holds whether the meta-data of an item is available.
*/

/*!
    \qmlproperty enum DocumentGalleryItem::itemType

    This property holds the type of a gallery item. It can be one of:

    \list
    \o DocumentGallery.InvalidType
    \o DocumentGallery.File
    \o DocumentGallery.Folder
    \o DocumentGallery.Document
    \o DocumentGallery.Text
    \o DocumentGallery.Audio
    \o DocumentGallery.Image
    \o DocumentGallery.Video
    \o DocumentGallery.Playlist
    \o DocumentGallery.Artist
    \o DocumentGallery.AlbumArtist
    \o DocumentGallery.Album
    \o DocumentGallery.AudioGenre
    \o DocumentGallery.PhotoAlbum
    \endlist
*/

QDeclarativeDocumentGallery::ItemType QDeclarativeDocumentGalleryItem::itemType() const
{
    return QDeclarativeDocumentGallery::itemTypeFromString(m_request.itemType());
}

/*!
    \qmlproperty url DocumentGalleryItem::itemUrl

    This property holds the URL of a gallery item.
*/

/*!
    \qmlproperty object DocumentGalleryItem::metaData

    This property holds the meta-data of a gallery item.
*/

/*!
    \qmlmethod DocumentGalleryItem::reload()

    Re-queries the gallery.
*/

/*!
    \qmlmethod DocumentGalleryItem::cancel()

    Cancels an executing request.
*/

/*!
    \qmlmethod DocumentGalleryItem::clear()

    Clears the results of a request.
*/

#include "moc_qdeclarativegalleryitem.cpp"

QTM_END_NAMESPACE
