Add new QXmppPubSubItem

Specialization of pubsub items now works via inheritance.
Parsing has been extended, now also supports the 'publisher' attribute.

1 files changed, 55 insertions, 12 deletions

diff --git a/src/base/QXmppPubSubItem.h b/src/base/QXmppPubSubItem.h
index dc470f59..eb697a0f 100644
--- a/src/base/QXmppPubSubItem.h
+++ b/src/base/QXmppPubSubItem.h
@@ -3,6 +3,7 @@
  *
  * Author:
  *  Jeremy Lainé
+ *  Linus Jahn
  *
  * Source:
  *  https://github.com/qxmpp-project/qxmpp
@@ -26,39 +27,81 @@
 
 #include "QXmppGlobal.h"
 
+#include <QDomElement>
+#include <QMetaType>
 #include <QSharedDataPointer>
 
-class QDomElement;
 class QXmlStreamWriter;
-
-class QXmppElement;
 class QXmppPubSubItemPrivate;
 
-/// \brief The QXmppPubSubItem class represents a publish-subscribe item
-/// as defined by \xep{0060}: Publish-Subscribe.
-
 class QXMPP_EXPORT QXmppPubSubItem
 {
 public:
-    QXmppPubSubItem();
-    QXmppPubSubItem(const QXmppPubSubItem &iq);
-    ~QXmppPubSubItem();
+    QXmppPubSubItem(const QString &id = {}, const QString &publisher = {});
+    QXmppPubSubItem(const QXmppPubSubItem &);
+    virtual ~QXmppPubSubItem();
 
-    QXmppPubSubItem &operator=(const QXmppPubSubItem &iq);
+    QXmppPubSubItem &operator=(const QXmppPubSubItem &);
 
     QString id() const;
     void setId(const QString &id);
 
-    QXmppElement contents() const;
-    void setContents(const QXmppElement &contents);
+    QString publisher() const;
+    void setPublisher(const QString &publisher);
 
     /// \cond
     void parse(const QDomElement &element);
     void toXml(QXmlStreamWriter *writer) const;
     /// \endcond
 
+    static bool isItem(const QDomElement &element);
+
+protected:
+    virtual void parsePayload(const QDomElement &payloadElement);
+    virtual void serializePayload(QXmlStreamWriter *writer) const;
+
+    template<typename PayloadChecker>
+    static bool isItem(const QDomElement &element, PayloadChecker isPayloadValid);
+
 private:
     QSharedDataPointer<QXmppPubSubItemPrivate> d;
 };
 
+///
+/// Returns true, if the element is a valid PubSub item and (if existant) the
+/// payload is correct.
+///
+/// \param element The element to be checked to be an &lt;item/&gt; element.
+/// \param isPayloadValid A function that validates the payload element (first
+/// child element). The functions needs to return true, if the payload is valid.
+/// In case there is no payload, the function is not called.
+///
+/// Here is an example covering how this could be used to check for the
+/// \xep{0118, User Tune} payload:
+/// \code
+/// auto isPayloadValid = [](const QDomElement &payload) -> bool {
+///     return payload.tagName() == "tune" && payload.namespaceURI() == ns_tune;
+/// };
+///
+/// bool valid = QXmppPubSubItem::isItem(itemElement, isPayloadValid);
+/// \endcode
+///
+template<typename PayloadChecker>
+bool QXmppPubSubItem::isItem(const QDomElement &element, PayloadChecker isPayloadValid)
+{
+    if (!isItem(element)) {
+        return false;
+    }
+
+    const QDomElement payload = element.firstChildElement();
+
+    // we can only check the payload if it's existant
+    if (!payload.isNull()) {
+        return isPayloadValid(payload);
+    }
+    return true;
+}
+
+Q_DECLARE_METATYPE(QXmppPubSubItem)
+
 #endif  // QXMPPPUBSUBITEM_H