Link Previews

Uses Matrix's preview API to generate embedded link previews.

Only title and description for now.

![image](/uploads/2c5d632480073fe54345cdbe22ea54dc/image.png)

src/linkpreviewer.cpp

@@ -0,0 +1,64 @@
+// SPDX-FileCopyrightText: 2022 Bharadwaj Raju <bharadwaj.raju777@protonmail.com>
+// SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-or-later OR LicenseRef-KDE-Accepted-GPL
+
+#include "linkpreviewer.h"
+
+#include "controller.h"
+
+LinkPreviewer::LinkPreviewer(QObject *parent)
+    : QObject(parent)
+    , m_loaded(false)
+{
+}
+
+bool LinkPreviewer::loaded() const
+{
+    return m_loaded;
+}
+
+QString LinkPreviewer::title() const
+{
+    return m_title;
+}
+
+QString LinkPreviewer::description() const
+{
+    return m_description;
+}
+
+QString LinkPreviewer::imageSource() const
+{
+    return m_imageSource;
+}
+
+QUrl LinkPreviewer::url() const
+{
+    return m_url;
+}
+
+void LinkPreviewer::setUrl(QUrl url)
+{
+    if (url.scheme() == QStringLiteral("https")) {
+        m_loaded = false;
+        Q_EMIT loadedChanged();
+
+        m_url = url;
+        Q_EMIT urlChanged();
+
+        auto conn = Controller::instance().activeConnection();
+
+        GetUrlPreviewJob *job = conn->callApi<GetUrlPreviewJob>(m_url.toString());
+
+        connect(job, &BaseJob::success, this, [this, job]() {
+            const auto json = job->jsonData();
+            m_title = json["og:title"].toString();
+            m_description = json["og:description"].toString();
+            m_imageSource = json["og:image"].toString();
+            m_loaded = true;
+            Q_EMIT titleChanged();
+            Q_EMIT descriptionChanged();
+            Q_EMIT imageSourceChanged();
+            Q_EMIT loadedChanged();
+        });
+    }
+}