Add (private) helpers for PEP managers

The code for PEP managers is often very similiar, this should make it a
bit easier.

1 files changed, 54 insertions, 0 deletions

diff --git a/src/client/QXmppPep_p.h b/src/client/QXmppPep_p.h
new file mode 100644
index 00000000..f525fdef
--- /dev/null
+++ b/src/client/QXmppPep_p.h
@@ -0,0 +1,54 @@
+// SPDX-FileCopyrightText: 2021 Linus Jahn <lnj@kaidan.im>
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+
+#include <QXmppPubSubEvent.h>
+#include <QXmppPubSubManager.h>
+
+namespace QXmpp::Private::Pep {
+
+template<typename T>
+using GetResult = std::variant<T, QXmppStanza::Error>;
+using PublishResult = std::variant<QString, QXmppStanza::Error>;
+
+template<typename ItemT>
+inline QFuture<GetResult<ItemT>> request(QXmppPubSubManager *pubSub, const QString &jid, const QString &nodeName, QObject *parent)
+{
+    using PubSub = QXmppPubSubManager;
+    using Error = QXmppStanza::Error;
+
+    auto process = [](PubSub::ItemsResult<ItemT> &&result) -> GetResult<ItemT> {
+        if (const auto itemsResult = std::get_if<PubSub::Items<ItemT>>(&result)) {
+            if (!itemsResult->items.isEmpty()) {
+                return itemsResult->items.takeFirst();
+            }
+            return Error(Error::Cancel, Error::ItemNotFound, QStringLiteral("User has no published items."));
+        } else {
+            return std::get<Error>(result);
+        }
+    };
+    return chain<GetResult<ItemT>>(pubSub->requestItems<ItemT>(jid, nodeName), parent, process);
+}
+
+// NodeName is a template parameter, so the right qstring comparison overload is used
+// (if we used 'const QString &' as type, a 'const char *' string would be converted)
+template<typename ItemT, typename NodeName, typename Manager, typename ReceivedSignal>
+inline bool handlePubSubEvent(const QDomElement &element, const QString &pubSubService, const QString &eventNode, NodeName nodeName, Manager *manager, ReceivedSignal itemReceived)
+{
+    if (eventNode == nodeName && QXmppPubSubEvent<ItemT>::isPubSubEvent(element)) {
+        QXmppPubSubEvent<ItemT> event;
+        event.parse(element);
+
+        if (event.eventType() == QXmppPubSubEventBase::Items) {
+            if (!event.items().isEmpty()) {
+                (manager->*itemReceived)(pubSubService, event.items().constFirst());
+            } else {
+                (manager->*itemReceived)(pubSubService, {});
+            }
+            return true;
+        }
+    }
+    return false;
+}
+
+}