Implement pause and resume action in Download Items

Adds the ability to pause downloads, and resume paused or interrupted
downloads.

Task-number: QTBUG-56840
Change-Id: I018bd30c3a772a36d48e4154d94f69cb8d8319e4
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

5 files changed, 82 insertions, 16 deletions

diff --git a/src/webenginewidgets/api/qwebenginedownloaditem.cpp b/src/webenginewidgets/api/qwebenginedownloaditem.cpp
index c1d9a3698..a5569e408 100644
--- a/src/webenginewidgets/api/qwebenginedownloaditem.cpp
+++ b/src/webenginewidgets/api/qwebenginedownloaditem.cpp
@@ -38,10 +38,12 @@
 ****************************************************************************/
 
 #include "qwebenginedownloaditem.h"
-
 #include "qwebenginedownloaditem_p.h"
+
+#include "browser_context_adapter.h"
 #include "qwebengineprofile_p.h"
 
+
 QT_BEGIN_NAMESPACE
 
 using QtWebEngineCore::BrowserContextAdapterClient;
@@ -116,6 +118,7 @@ QWebEngineDownloadItemPrivate::QWebEngineDownloadItemPrivate(QWebEngineProfilePr
     , type(QWebEngineDownloadItem::Attachment)
     , interruptReason(QWebEngineDownloadItem::NoReason)
     , downloadUrl(url)
+    , downloadPaused(false)
     , totalBytes(-1)
     , receivedBytes(0)
 {
@@ -145,10 +148,16 @@ void QWebEngineDownloadItemPrivate::update(const BrowserContextAdapterClient::Do
         Q_EMIT q->downloadProgress(receivedBytes, totalBytes);
     }
 
-    downloadFinished = downloadState != QWebEngineDownloadItem::DownloadInProgress;
+    if (info.done != downloadFinished) {
+        downloadFinished = info.done;
+        if (downloadFinished)
+            Q_EMIT q->finished();
+    }
 
-    if (downloadFinished)
-        Q_EMIT q->finished();
+    if (downloadPaused != info.paused) {
+        downloadPaused = info.paused;
+        Q_EMIT q->isPausedChanged(downloadPaused);
+    }
 }
 
 /*!
@@ -184,13 +193,50 @@ void QWebEngineDownloadItem::cancel()
             || state == QWebEngineDownloadItem::DownloadCancelled)
         return;
 
-    d->downloadState = QWebEngineDownloadItem::DownloadCancelled;
-    Q_EMIT stateChanged(d->downloadState);
-
     // We directly cancel the download request if the user cancels
     // before it even started, so no need to notify the profile here.
     if (state == QWebEngineDownloadItem::DownloadInProgress)
-        d->profile->cancelDownload(d->downloadId);
+        d->profile->browserContext()->cancelDownload(d->downloadId);
+    else {
+        d->downloadState = QWebEngineDownloadItem::DownloadCancelled;
+        Q_EMIT stateChanged(d->downloadState);
+    }
+}
+
+/*!
+    \since 5.10
+    Pauses the current download. Has no effect if the state is not \c DownloadInProgress.
+
+    \sa resume()
+*/
+
+void QWebEngineDownloadItem::pause()
+{
+    Q_D(QWebEngineDownloadItem);
+
+    QWebEngineDownloadItem::DownloadState state = d->downloadState;
+
+    if (state != QWebEngineDownloadItem::DownloadInProgress)
+        return;
+
+    d->profile->browserContext()->pauseDownload(d->downloadId);
+}
+
+/*!
+    \since 5.10
+    Resumes the current download if it was paused or interrupted.
+
+    \sa pause(), isPaused(), state()
+*/
+void QWebEngineDownloadItem::resume()
+{
+    Q_D(QWebEngineDownloadItem);
+
+    QWebEngineDownloadItem::DownloadState state = d->downloadState;
+
+    if (d->downloadFinished || (state != QWebEngineDownloadItem::DownloadInProgress && state != QWebEngineDownloadItem::DownloadInterrupted))
+        return;
+    d->profile->browserContext()->resumeDownload(d->downloadId);
 }
 
 /*!
@@ -206,12 +252,21 @@ quint32 QWebEngineDownloadItem::id() const
 /*!
     \fn QWebEngineDownloadItem::finished()
 
-    This signal is emitted whenever the download finishes.
+    This signal is emitted when the download finishes.
 
     \sa state(), isFinished()
 */
 
 /*!
+    \fn QWebEngineDownloadItem::isPausedChanged(bool isPaused)
+    \since 5.10
+
+    This signal is emitted whenever \a isPaused changes.
+
+    \sa pause(), isPaused()
+*/
+
+/*!
     \fn QWebEngineDownloadItem::stateChanged(DownloadState state)
 
     This signal is emitted whenever the download's \a state changes.
@@ -407,7 +462,7 @@ void QWebEngineDownloadItem::setPath(QString path)
 }
 
 /*!
-    Returns whether this download is finished (not in progress).
+    Returns whether this download is finished (completed, cancelled, or non-resumable interrupted state).
 
     \sa finished(), state(),
 */
@@ -419,6 +474,18 @@ bool QWebEngineDownloadItem::isFinished() const
 }
 
 /*!
+    Returns whether this download is paused.
+
+    \sa pause()
+*/
+
+bool QWebEngineDownloadItem::isPaused() const
+{
+    Q_D(const QWebEngineDownloadItem);
+    return d->downloadPaused;
+}
+
+/*!
     Returns the format the web page will be saved in if this is a download request for a web page.
     \since 5.7
 
diff --git a/src/webenginewidgets/api/qwebenginedownloaditem.h b/src/webenginewidgets/api/qwebenginedownloaditem.h
index a4b6c08aa..2aca2bb2a 100644
--- a/src/webenginewidgets/api/qwebenginedownloaditem.h
+++ b/src/webenginewidgets/api/qwebenginedownloaditem.h
@@ -120,6 +120,7 @@ public:
     QString path() const;
     void setPath(QString path);
     bool isFinished() const;
+    bool isPaused() const;
     SavePageFormat savePageFormat() const;
     void setSavePageFormat(SavePageFormat format);
     DownloadType type() const;
@@ -129,11 +130,14 @@ public:
 public Q_SLOTS:
     void accept();
     void cancel();
+    void pause();
+    void resume();
 
 Q_SIGNALS:
     void finished();
     void stateChanged(QWebEngineDownloadItem::DownloadState state);
     void downloadProgress(qint64 bytesReceived, qint64 bytesTotal);
+    void isPausedChanged(bool isPaused);
 
 private:
     Q_DISABLE_COPY(QWebEngineDownloadItem)
diff --git a/src/webenginewidgets/api/qwebenginedownloaditem_p.h b/src/webenginewidgets/api/qwebenginedownloaditem_p.h
index 038332da3..da765e5c5 100644
--- a/src/webenginewidgets/api/qwebenginedownloaditem_p.h
+++ b/src/webenginewidgets/api/qwebenginedownloaditem_p.h
@@ -77,6 +77,7 @@ public:
     QString downloadPath;
     const QUrl downloadUrl;
     QString mimeType;
+    bool downloadPaused;
 
     qint64 totalBytes;
     qint64 receivedBytes;
diff --git a/src/webenginewidgets/api/qwebengineprofile.cpp b/src/webenginewidgets/api/qwebengineprofile.cpp
index cd4fc8b02..dae0cbdfc 100644
--- a/src/webenginewidgets/api/qwebengineprofile.cpp
+++ b/src/webenginewidgets/api/qwebengineprofile.cpp
@@ -172,11 +172,6 @@ QWebEngineProfilePrivate::~QWebEngineProfilePrivate()
     m_ongoingDownloads.clear();
 }
 
-void QWebEngineProfilePrivate::cancelDownload(quint32 downloadId)
-{
-    browserContext()->cancelDownload(downloadId);
-}
-
 void QWebEngineProfilePrivate::downloadDestroyed(quint32 downloadId)
 {
     m_ongoingDownloads.remove(downloadId);
diff --git a/src/webenginewidgets/api/qwebengineprofile_p.h b/src/webenginewidgets/api/qwebengineprofile_p.h
index 4d31c5a81..c5a75f6d4 100644
--- a/src/webenginewidgets/api/qwebengineprofile_p.h
+++ b/src/webenginewidgets/api/qwebengineprofile_p.h
@@ -76,7 +76,6 @@ public:
     QSharedPointer<QtWebEngineCore::BrowserContextAdapter> browserContext() const { return m_browserContextRef; }
     QWebEngineSettings *settings() const { return m_settings; }
 
-    void cancelDownload(quint32 downloadId);
     void downloadDestroyed(quint32 downloadId);
 
     void downloadRequested(DownloadItemInfo &info) Q_DECL_OVERRIDE;