Add ReviewModel element.

Use a data model for fetching and handling place reviews.

Change-Id: I066d97bd8c4b7897c2a471da346f135ea69524c3
Reviewed-on: http://codereview.qt.nokia.com/2012
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Aaron McCarthy <aaron.mccarthy@nokia.com>

1 files changed, 219 insertions, 0 deletions

diff --git a/src/imports/location/declarativeplaces/qdeclarativereviewmodel.cpp b/src/imports/location/declarativeplaces/qdeclarativereviewmodel.cpp
new file mode 100644
index 00000000..6364a4c6
--- /dev/null
+++ b/src/imports/location/declarativeplaces/qdeclarativereviewmodel.cpp
@@ -0,0 +1,219 @@
+#include "qdeclarativereviewmodel_p.h"
+#include <qdeclarativeplace_p.h>
+
+QT_USE_NAMESPACE
+
+/*!
+    \qmlclass ReviewModel QDeclarativeReviewModel
+
+    \brief The ReviewModel element provides access to reviews of a Place.
+    \ingroup qml-places
+    \since 5.0
+
+    The ReviewModel is a read-only model used to fetch reviews about a Place.  The model
+    incrementally fetches reviews.  The number of reviews which are fetched at a time is specified
+    by the batchSize property.  The total number of reviews available can be accessed via the
+    totalCount property and the number of fetched reviews via the count property.
+
+    The model provides a single data role, the "review" role, which returns a Review object.
+*/
+
+QDeclarativeReviewModel::QDeclarativeReviewModel(QObject* parent)
+:   QAbstractListModel(parent), m_place(0), m_batchSize(1), m_reviewCount(-1),
+    m_manager(new QPlaceManager(this)), m_reply(0)
+{
+    QHash<int, QByteArray> roleNames;
+    roleNames.insert(ReviewRole, "review");
+    setRoleNames(roleNames);
+}
+
+QDeclarativeReviewModel::~QDeclarativeReviewModel()
+{
+    qDeleteAll(m_reviews);
+}
+
+/*!
+    \qmlproperty Place ReviewModel::place
+
+    This property holds the Place that the reviews are for.
+*/
+QDeclarativePlace *QDeclarativeReviewModel::place() const
+{
+    return m_place;
+}
+
+void QDeclarativeReviewModel::setPlace(QDeclarativePlace *place)
+{
+    if (m_place != place) {
+        beginResetModel();
+        if (m_reply) {
+            m_reply->abort();
+            m_reply->deleteLater();
+            m_reply = 0;
+        }
+        qDeleteAll(m_reviews);
+        endResetModel();
+
+        m_reviewCount = -1;
+        emit totalCountChanged();
+
+        m_place = place;
+        emit placeChanged();
+
+        fetchMore(QModelIndex());
+    }
+}
+
+/*!
+    \qmlproperty int ReviewModel::batchSize
+
+    This property holds the batch size to use when fetching more reviews.
+*/
+int QDeclarativeReviewModel::batchSize() const
+{
+    return m_batchSize;
+}
+
+void QDeclarativeReviewModel::setBatchSize(int batchSize)
+{
+    if (m_batchSize != batchSize) {
+        m_batchSize = batchSize;
+        emit batchSizeChanged();
+    }
+}
+
+/*!
+    \qmlproperty int ReviewModel::totalCount
+
+    This property holds the total number of reviews for the place.
+*/
+int QDeclarativeReviewModel::totalCount() const
+{
+    return m_reviewCount;
+}
+
+static QPair<int, int> findMissingKey(const QMap<int, QDeclarativeReview *> &map)
+{
+    int start = 0;
+    while (map.value(start, 0) != 0)
+        ++start;
+
+    QMap<int, QDeclarativeReview *>::const_iterator it = map.lowerBound(start);
+    if (it == map.end())
+        return qMakePair(start, -1);
+
+    int end = start;
+    while (map.value(end, 0) == 0)
+        ++end;
+
+    return qMakePair(start, end - 1);
+}
+
+bool QDeclarativeReviewModel::canFetchMore(const QModelIndex &parent) const
+{
+    if (parent.isValid())
+        return false;
+
+    if (!m_place)
+        return false;
+
+    if (m_reviewCount == -1)
+        return true;
+
+    return m_reviews.count() != m_reviewCount;
+}
+
+void QDeclarativeReviewModel::fetchMore(const QModelIndex &parent)
+{
+    if (parent.isValid())
+        return;
+
+    if (!m_place)
+        return;
+
+    if (m_reply)
+        return;
+
+    QPlaceQuery query;
+
+    if (m_reviewCount == -1) {
+        query.setOffset(0);
+        query.setLimit(m_batchSize);
+    } else {
+        QPair<int, int> missing = findMissingKey(m_reviews);
+        query.setOffset(missing.first);
+        if (missing.second == -1)
+            query.setLimit(m_batchSize);
+        else
+            query.setLimit(qMin(m_batchSize, missing.second - missing.first + 1));
+    }
+
+    m_reply = m_manager->getReviews(m_place->place(), query);
+    connect(m_reply, SIGNAL(finished()), this, SLOT(fetchFinished()), Qt::QueuedConnection);
+}
+
+void QDeclarativeReviewModel::clear()
+{
+    beginResetModel();
+    m_reviewCount = -1;
+    qDeleteAll(m_reviews);
+    m_reviews.clear();
+    delete m_reply;
+    m_reply = 0;
+    endResetModel();
+}
+
+void QDeclarativeReviewModel::classBegin()
+{
+}
+
+void QDeclarativeReviewModel::componentComplete()
+{
+    fetchMore(QModelIndex());
+}
+
+void QDeclarativeReviewModel::fetchFinished()
+{
+    QPlaceReviewReply *reply = m_reply;
+    m_reply = 0;
+
+    if (m_reviewCount != reply->totalCount()) {
+        m_reviewCount = reply->totalCount();
+        emit totalCountChanged();
+    }
+
+    if (reply->reviews().items() > 0) {
+        int startIndex = reply->reviews().start();
+
+        QList<QPlaceReview> reviews = reply->reviews().data();
+
+        beginInsertRows(QModelIndex(), startIndex, startIndex + reviews.length() - 1);
+        for (int i = 0; i < reviews.length(); ++i)
+            m_reviews.insert(startIndex + i, new QDeclarativeReview(reviews.at(i), this));
+        endInsertRows();
+    }
+
+    reply->deleteLater();
+}
+
+int QDeclarativeReviewModel::rowCount(const QModelIndex &parent) const
+{
+    if (parent.isValid())
+        return 0;
+
+    return m_reviews.count();
+}
+
+QVariant QDeclarativeReviewModel::data(const QModelIndex &index, int role) const
+{
+    if (!index.isValid())
+        return QVariant();
+
+    if (index.row() >= rowCount(index.parent()) || index.row() < 0)
+        return QVariant();
+
+    if (role == ReviewRole)
+        return QVariant::fromValue(static_cast<QObject *>(m_reviews.value(index.row())));
+
+    return QVariant();
+}