Update QML download API to match widgets and add documentation

Rename the download signal to downloadRequested and only start a
download if it has been explicitly accepted by the user, else cancel
it by default.
Replace the downloadPercentage property with totalBytes and receivedBytes
to also give the user information about download size.
Additionally this patch adds missing documentation.

Change-Id: I9d895386cf033f2efffe3ebac6f08f94c6fe0c19
Reviewed-by: Michael Brüning <michael.bruning@theqtcompany.com>
Reviewed-by: Jocelyn Turcotte <jturcotte@woboq.com>

5 files changed, 203 insertions, 56 deletions

diff --git a/src/webengine/api/qquickwebenginedownloaditem.cpp b/src/webengine/api/qquickwebenginedownloaditem.cpp
index 967638b7e..6ee00d9a0 100644
--- a/src/webengine/api/qquickwebenginedownloaditem.cpp
+++ b/src/webengine/api/qquickwebenginedownloaditem.cpp
@@ -39,12 +39,26 @@
 
 QT_BEGIN_NAMESPACE
 
+static inline QQuickWebEngineDownloadItem::DownloadState toDownloadState(int state) {
+    switch (state) {
+    case BrowserContextAdapterClient::DownloadInProgress:
+        return QQuickWebEngineDownloadItem::DownloadInProgress;
+    case BrowserContextAdapterClient::DownloadCompleted:
+        return QQuickWebEngineDownloadItem::DownloadCompleted;
+    case BrowserContextAdapterClient::DownloadCancelled:
+        return QQuickWebEngineDownloadItem::DownloadCancelled;
+    case BrowserContextAdapterClient::DownloadInterrupted:
+        return QQuickWebEngineDownloadItem::DownloadInterrupted;
+    default:
+        Q_UNREACHABLE();
+        return QQuickWebEngineDownloadItem::DownloadCancelled;
+    }
+}
+
 QQuickWebEngineDownloadItemPrivate::QQuickWebEngineDownloadItemPrivate(QQuickWebEngineProfilePrivate *p)
     : profile(p)
-    , downloadStarted(false)
     , downloadId(-1)
     , downloadState(QQuickWebEngineDownloadItem::DownloadCancelled)
-    , downloadProgress(0)
 {
 }
 
@@ -53,64 +67,189 @@ QQuickWebEngineDownloadItemPrivate::~QQuickWebEngineDownloadItemPrivate()
     profile->downloadDestroyed(downloadId);
 }
 
-void QQuickWebEngineDownloadItemPrivate::update(QQuickWebEngineDownloadItem::DownloadState state, int progress)
+/*!
+    \qmltype WebEngineDownloadItem
+    \instantiates QQuickWebEngineDownloadItem
+    \inqmlmodule QtWebEngine 1.1
+    \since QtWebEngine 1.1
+    \brief A WebEngineDownloadItem provides information about a download.
+
+    WebEngineDownloadItem stores the state of a download to be used to manage requested downloads.
+
+    By default the download is rejected unless the user explicitly accepts it with
+    WebEngineDownloadItem::accept().
+*/
+
+void QQuickWebEngineDownloadItemPrivate::update(const BrowserContextAdapterClient::DownloadItemInfo &info)
 {
     Q_Q(QQuickWebEngineDownloadItem);
-    if (state != downloadState) {
-        downloadState = state;
-        Q_EMIT q->stateChanged();
+
+    updateState(toDownloadState(info.state));
+
+    if (info.receivedBytes != receivedBytes) {
+        receivedBytes = info.receivedBytes;
+        Q_EMIT q->receivedBytesChanged();
+    }
+
+    if (info.totalBytes != totalBytes) {
+        totalBytes = info.totalBytes;
+        Q_EMIT q->totalBytesChanged();
     }
-    if (progress != downloadProgress) {
-        downloadProgress = progress;
-        Q_EMIT q->progressChanged();
+}
+
+void QQuickWebEngineDownloadItemPrivate::updateState(QQuickWebEngineDownloadItem::DownloadState newState)
+{
+    Q_Q(QQuickWebEngineDownloadItem);
+
+    if (downloadState != newState) {
+        downloadState = newState;
+        Q_EMIT q->stateChanged();
     }
 }
 
+/*!
+    \qmlmethod void WebEngineDownloadItem::accept()
+
+    Accepts the download request, which will start the download.
+
+   \sa WebEngineDownloadItem::cancel()
+*/
+
+void QQuickWebEngineDownloadItem::accept()
+{
+    Q_D(QQuickWebEngineDownloadItem);
+
+    if (d->downloadState != QQuickWebEngineDownloadItem::DownloadRequested)
+        return;
+
+    d->updateState(QQuickWebEngineDownloadItem::DownloadInProgress);
+}
+
+/*!
+    \qmlmethod void WebEngineDownloadItem::cancel()
+
+    Cancels the download.
+*/
+
 void QQuickWebEngineDownloadItem::cancel()
 {
     Q_D(QQuickWebEngineDownloadItem);
 
-    if (d->downloadState == QQuickWebEngineDownloadItem::DownloadCompleted
-            || d->downloadState == QQuickWebEngineDownloadItem::DownloadCancelled)
+    QQuickWebEngineDownloadItem::DownloadState state = d->downloadState;
+
+    if (state == QQuickWebEngineDownloadItem::DownloadCompleted
+            || state == QQuickWebEngineDownloadItem::DownloadCancelled)
         return;
 
-    d->update(QQuickWebEngineDownloadItem::DownloadCancelled, d->downloadProgress);
+    d->updateState(QQuickWebEngineDownloadItem::DownloadCancelled);
 
     // We directly cancel the download if the user cancels before
     // it even started, so no need to notify the profile here.
-    if (d->downloadStarted)
+    if (state == QQuickWebEngineDownloadItem::DownloadInProgress)
         d->profile->cancelDownload(d->downloadId);
 }
 
-quint32 QQuickWebEngineDownloadItem::id()
+/*!
+    \qmlproperty quint32 WebEngineDownloadItem::id
+
+    The download item's id.
+*/
+
+quint32 QQuickWebEngineDownloadItem::id() const
 {
-    Q_D(QQuickWebEngineDownloadItem);
+    Q_D(const QQuickWebEngineDownloadItem);
     return d->downloadId;
 }
 
-QQuickWebEngineDownloadItem::DownloadState QQuickWebEngineDownloadItem::state()
+/*!
+    \qmlproperty enumeration WebEngineDownloadItem::state
+
+    This property describes the state in which the download is in.
+
+    The state can be one of:
+
+    \table
+
+    \header
+    \li Constant
+    \li Description
+
+    \row
+    \li DownloadRequested
+    \li The download has been requested, but has not been accepted yet.
+
+    \row
+    \li DownloadInProgress
+    \li The download is in progress.
+
+    \row
+    \li DownloadCompleted
+    \li The download completed successfully.
+
+    \row
+    \li DownloadInterrupted
+    \li The download has been interrupted (by the server or because of lost connectivity).
+
+    \endtable
+*/
+
+QQuickWebEngineDownloadItem::DownloadState QQuickWebEngineDownloadItem::state() const
 {
-    Q_D(QQuickWebEngineDownloadItem);
+    Q_D(const QQuickWebEngineDownloadItem);
     return d->downloadState;
 }
 
-int QQuickWebEngineDownloadItem::progress()
+/*!
+    \qmlproperty int WebEngineDownloadItem::totalBytes
+
+    The download's total size in bytes.
+
+    -1 means the total size is unknown.
+*/
+
+qint64 QQuickWebEngineDownloadItem::totalBytes() const
 {
-    Q_D(QQuickWebEngineDownloadItem);
-    return d->downloadProgress;
+    Q_D(const QQuickWebEngineDownloadItem);
+    return d->totalBytes;
 }
 
-QString QQuickWebEngineDownloadItem::path()
+/*!
+    \qmlproperty int WebEngineDownloadItem::receivedBytes
+
+    The download's bytes that have been received so far.
+*/
+
+qint64 QQuickWebEngineDownloadItem::receivedBytes() const
 {
-    Q_D(QQuickWebEngineDownloadItem);
+    Q_D(const QQuickWebEngineDownloadItem);
+    return d->receivedBytes;
+}
+
+/*!
+    \qmlproperty QString WebEngineDownloadItem::path
+
+    The download item's full target path where it is being downloaded to.
+
+    The path includes the file name. The default suggested path is the standard
+    download location and file name is deduced not to overwrite already existing files.
+
+    The download path can only be set in the \c WebEngineProfile.onDownloadRequested
+    handler before the download is accepted.
+
+    \sa WebEngineProfile::downloadRequested(WebEngineDownloadItem download), WebEngineDownloadItem::accept()
+*/
+
+QString QQuickWebEngineDownloadItem::path() const
+{
+    Q_D(const QQuickWebEngineDownloadItem);
     return d->downloadPath;
 }
 
 void QQuickWebEngineDownloadItem::setPath(QString path)
 {
     Q_D(QQuickWebEngineDownloadItem);
-    if (d->downloadStarted) {
-        qWarning("Setting the download path is not allowed after the download has been started.");
+    if (d->downloadState != QQuickWebEngineDownloadItem::DownloadRequested) {
+        qWarning("Setting the download path is not allowed after the download has been accepted.");
         return;
     }
     if (d->downloadPath != path) {
diff --git a/src/webengine/api/qquickwebenginedownloaditem_p.h b/src/webengine/api/qquickwebenginedownloaditem_p.h
index 2cb140acc..ea12c9c94 100644
--- a/src/webengine/api/qquickwebenginedownloaditem_p.h
+++ b/src/webengine/api/qquickwebenginedownloaditem_p.h
@@ -52,6 +52,7 @@ class Q_WEBENGINE_PRIVATE_EXPORT QQuickWebEngineDownloadItem: public QObject {
 public:
     ~QQuickWebEngineDownloadItem();
     enum DownloadState {
+        DownloadRequested,
         DownloadInProgress,
         DownloadCompleted,
         DownloadCancelled,
@@ -61,20 +62,24 @@ public:
 
     Q_PROPERTY(quint32 id READ id() CONSTANT FINAL)
     Q_PROPERTY(DownloadState state READ state NOTIFY stateChanged)
-    Q_PROPERTY(int progress READ progress NOTIFY progressChanged)
+    Q_PROPERTY(qint64 totalBytes READ totalBytes NOTIFY totalBytesChanged)
+    Q_PROPERTY(qint64 receivedBytes READ receivedBytes NOTIFY receivedBytesChanged)
     Q_PROPERTY(QString path READ path WRITE setPath NOTIFY pathChanged)
 
+    Q_INVOKABLE void accept();
     Q_INVOKABLE void cancel();
 
-    quint32 id();
-    DownloadState state();
-    int progress();
-    QString path();
+    quint32 id() const;
+    DownloadState state() const;
+    qint64 totalBytes() const;
+    qint64 receivedBytes() const;
+    QString path() const;
     void setPath(QString path);
 
 Q_SIGNALS:
     void stateChanged();
-    void progressChanged();
+    void receivedBytesChanged();
+    void totalBytesChanged();
     void pathChanged();
 
 private:
diff --git a/src/webengine/api/qquickwebenginedownloaditem_p_p.h b/src/webengine/api/qquickwebenginedownloaditem_p_p.h
index 6b724b4c9..0250a8faa 100644
--- a/src/webengine/api/qquickwebenginedownloaditem_p_p.h
+++ b/src/webengine/api/qquickwebenginedownloaditem_p_p.h
@@ -53,13 +53,14 @@ public:
     QQuickWebEngineDownloadItemPrivate(QQuickWebEngineProfilePrivate *p);
     ~QQuickWebEngineDownloadItemPrivate();
 
-    bool downloadStarted;
     quint32 downloadId;
     QQuickWebEngineDownloadItem::DownloadState downloadState;
-    int downloadProgress;
+    qint64 totalBytes;
+    qint64 receivedBytes;
     QString downloadPath;
 
-    void update(QQuickWebEngineDownloadItem::DownloadState state, int progress);
+    void update(const BrowserContextAdapterClient::DownloadItemInfo &info);
+    void updateState(QQuickWebEngineDownloadItem::DownloadState newState);
 };
 
 QT_END_NAMESPACE
diff --git a/src/webengine/api/qquickwebengineprofile.cpp b/src/webengine/api/qquickwebengineprofile.cpp
index 791f39263..cac309291 100644
--- a/src/webengine/api/qquickwebengineprofile.cpp
+++ b/src/webengine/api/qquickwebengineprofile.cpp
@@ -48,22 +48,6 @@
 
 QT_BEGIN_NAMESPACE
 
-static inline QQuickWebEngineDownloadItem::DownloadState toDownloadState(int state) {
-    switch (state) {
-    case BrowserContextAdapterClient::DownloadInProgress:
-        return QQuickWebEngineDownloadItem::DownloadInProgress;
-    case BrowserContextAdapterClient::DownloadCompleted:
-        return QQuickWebEngineDownloadItem::DownloadCompleted;
-    case BrowserContextAdapterClient::DownloadCancelled:
-        return QQuickWebEngineDownloadItem::DownloadCancelled;
-    case BrowserContextAdapterClient::DownloadInterrupted:
-        return QQuickWebEngineDownloadItem::DownloadInterrupted;
-    default:
-        Q_UNREACHABLE();
-        return QQuickWebEngineDownloadItem::DownloadCancelled;
-    }
-}
-
 QQuickWebEngineProfilePrivate::QQuickWebEngineProfilePrivate(BrowserContextAdapter* browserContext, bool ownsContext)
         : m_settings(new QQuickWebEngineSettings())
         , m_browserContext(browserContext)
@@ -95,7 +79,6 @@ void QQuickWebEngineProfilePrivate::cancelDownload(quint32 downloadId)
 void QQuickWebEngineProfilePrivate::downloadDestroyed(quint32 downloadId)
 {
     m_ongoingDownloads.remove(downloadId);
-    cancelDownload(downloadId);
 }
 
 void QQuickWebEngineProfilePrivate::downloadRequested(DownloadItemInfo &info)
@@ -105,7 +88,7 @@ void QQuickWebEngineProfilePrivate::downloadRequested(DownloadItemInfo &info)
     Q_ASSERT(!m_ongoingDownloads.contains(info.id));
     QQuickWebEngineDownloadItemPrivate *itemPrivate = new QQuickWebEngineDownloadItemPrivate(this);
     itemPrivate->downloadId = info.id;
-    itemPrivate->downloadState = QQuickWebEngineDownloadItem::DownloadInProgress;
+    itemPrivate->downloadState = QQuickWebEngineDownloadItem::DownloadRequested;
     itemPrivate->downloadPath = info.path;
 
     QQuickWebEngineDownloadItem *download = new QQuickWebEngineDownloadItem(itemPrivate, q);
@@ -113,11 +96,12 @@ void QQuickWebEngineProfilePrivate::downloadRequested(DownloadItemInfo &info)
     m_ongoingDownloads.insert(info.id, download);
 
     QQmlEngine::setObjectOwnership(download, QQmlEngine::JavaScriptOwnership);
-    Q_EMIT q->downloadStarted(download);
-    download->d_func()->downloadStarted = true;
+    Q_EMIT q->downloadRequested(download);
 
+    QQuickWebEngineDownloadItem::DownloadState state = download->state();
     info.path = download->path();
-    info.cancelled = download->state() == QQuickWebEngineDownloadItem::DownloadCancelled;
+    info.cancelled = state == QQuickWebEngineDownloadItem::DownloadCancelled
+                      || state == QQuickWebEngineDownloadItem::DownloadRequested;
 }
 
 void QQuickWebEngineProfilePrivate::downloadUpdated(const DownloadItemInfo &info)
@@ -134,7 +118,7 @@ void QQuickWebEngineProfilePrivate::downloadUpdated(const DownloadItemInfo &info
         return;
     }
 
-    download->d_func()->update(toDownloadState(info.state), info.percentComplete);
+    download->d_func()->update(info);
 
     if (info.state != BrowserContextAdapterClient::DownloadInProgress) {
         Q_EMIT q->downloadFinished(download);
@@ -156,6 +140,24 @@ void QQuickWebEngineProfilePrivate::downloadUpdated(const DownloadItemInfo &info
     belongs to.
 */
 
+/*!
+    \qmlsignal WebEngineProfile::downloadRequested(WebEngineDownloadItem download)
+
+    This signal is emitted whenever a download has been triggered.
+    The \a download argument holds the state of the download.
+    The \a download has to be explicitly accepted with WebEngineDownloadItem::accept(),
+    else the download will be cancelled by default.
+*/
+
+/*!
+    \qmlsignal WebEngineProfile::downloadFinished(WebEngineDownloadItem download)
+
+    This signal is emitted whenever a download finishes downloading.
+    This can be due to the download finishing successfully, being cancelled or
+    interrupted by lost connectivity for example.
+    The \a download argument holds the state of the finished download instance.
+*/
+
 QQuickWebEngineProfile::QQuickWebEngineProfile()
     : d_ptr(new QQuickWebEngineProfilePrivate(new BrowserContextAdapter(false), true))
 {
diff --git a/src/webengine/api/qquickwebengineprofile_p.h b/src/webengine/api/qquickwebengineprofile_p.h
index 7a2ff08e1..f3e0f5c33 100644
--- a/src/webengine/api/qquickwebengineprofile_p.h
+++ b/src/webengine/api/qquickwebengineprofile_p.h
@@ -112,7 +112,7 @@ signals:
     void persistentCookiesPolicyChanged();
     void httpCacheMaximumSizeChanged();
 
-    void downloadStarted(QQuickWebEngineDownloadItem *download);
+    void downloadRequested(QQuickWebEngineDownloadItem *download);
     void downloadFinished(QQuickWebEngineDownloadItem *download);
 
 private: