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#include "qdeclarativegallerytype.h"


#include <qgalleryresultset.h>

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

QTM_BEGIN_NAMESPACE

QDeclarativeGalleryType::QDeclarativeGalleryType(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(typeChanged()),
            this, SLOT(_q_typeChanged()));
    connect(&m_request, SIGNAL(metaDataChanged(QList<int>)),
            this, SLOT(_q_metaDataChanged(QList<int>)));

    m_metaData = new QDeclarativePropertyMap(this);
}

QDeclarativeGalleryType::~QDeclarativeGalleryType()
{
}

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

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

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

        emit propertyNamesChanged();
    }
}

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

    if (!m_request.itemType().isEmpty())
        m_request.execute();
}

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

    m_request.execute();
}

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

    m_request.cancel();
}

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

    m_request.clear();
}

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

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

bool QDeclarativeGalleryType::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 QDeclarativeGalleryType::_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::ItemTypeError:
                qmlInfo(this) << tr("DocumentGallery.%1 is not a supported item type")
                        .arg(m_request.itemType());
                break;
            default:
                break;
            }
        }
        emit statusChanged();
    } else if (m_status == Idle && !m_request.autoUpdate()) {
        m_request.cancel();
    } else {
        emit statusChanged();
    }
}

void QDeclarativeGalleryType::_q_typeChanged()
{
    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 QDeclarativeGalleryType::_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 DocumentGalleryType QDeclarativeDocumentGalleryType

    \inmodule QtGallery
    \ingroup qml-gallery

    \brief The DocumentGalleryType element allows you to request information
    about an item type from the document gallery.

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

    \sa DocumentGalleryModel, DocumentGalleryItem
*/

QDeclarativeDocumentGalleryType::QDeclarativeDocumentGalleryType(QObject *parent)
    : QDeclarativeGalleryType(parent)
{
}

QDeclarativeDocumentGalleryType::~QDeclarativeDocumentGalleryType()
{
}

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

/*!
    \qmlproperty enum DocumentGalleryType::status

    This property holds the status of a type request.  It can be one of:

    \list
    \o Null No \l itemType has been specified.
    \o Active Information about an \l itemType is being fetched from the gallery.
    \o Finished Information about an \l itemType is available.
    \o Idle Information about an \l itemType 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 DocumentGalleryType::progress

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

/*!
    \qmlproperty QStringList DocumentGalleryType::properties

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

/*!
    \qmlproperty bool DocumentGalleryType::autoUpdate

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

/*!
    \qmlproperty enum DocumentGalleryType::itemType

    This property holds the item type that a request fetches information about.
    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 QDeclarativeDocumentGalleryType::itemType() const
{
    return QDeclarativeDocumentGallery::itemTypeFromString(m_request.itemType());
}

void QDeclarativeDocumentGalleryType::setItemType(QDeclarativeDocumentGallery::ItemType itemType)
{
    const QString type = QDeclarativeDocumentGallery::toString(itemType);

    if (type != m_request.itemType()) {
        m_request.setItemType(type);

        if (m_updateStatus != Incomplete) {
            if (!type.isEmpty())
                m_request.execute();
            else
                m_request.clear();
        }

        emit itemTypeChanged();
    }
}

/*!
    \qmlproperty bool DocumentGalleryType::available

    This property holds whether the meta-data of a type is available.
*/

/*!
    \qmlproperty object DocumentGalleryType::metaData

    This property holds the meta-data of an item type/
*/

/*!
    \qmlmethod DocumentGalleryType::reload()

    Re-queries the gallery.
*/

/*!
    \qmlmethod DocumentGalleryType::cancel()

    Cancels an executing request.
*/

/*!
    \qmlmethod DocumentGalleryType::clear()

    Clears the results of a request.
*/

#include "moc_qdeclarativegallerytype.cpp"

QTM_END_NAMESPACE
