1 files changed, 86 insertions, 0 deletions

diff --git a/common/propertymapper.h b/common/propertymapper.h
new file mode 100644
index 0000000..0c6c16f
--- /dev/null
+++ b/common/propertymapper.h
@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2014 Christian Mollekopf <chrigi_1@fastmail.fm>
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the
+ *   Free Software Foundation, Inc.,
+ *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
+ */
+
+#pragma once
+
+#include <QVariant>
+#include <QByteArray>
+#include <functional>
+#include <flatbuffers/flatbuffers.h>
+
+/**
+ * Defines how to convert qt primitives to flatbuffer ones
+ */
+template <class T>
+flatbuffers::uoffset_t variantToProperty(const QVariant &, flatbuffers::FlatBufferBuilder &fbb);
+
+/**
+ * Defines how to convert flatbuffer primitives to qt ones
+ */
+template <typename T>
+QVariant propertyToVariant(const flatbuffers::String *);
+
+
+/**
+ * The property mapper is a non-typesafe virtual dispatch.
+ *
+ * Instead of using an interface and requring each implementation to override
+ * a virtual method per property, the property mapper can be filled with accessors
+ * that extract the properties from resource types.
+ */
+template<typename BufferType>
+class ReadPropertyMapper
+{
+public:
+    virtual QVariant getProperty(const QByteArray &key, BufferType const *buffer) const
+    {
+        if (mReadAccessors.contains(key)) {
+            auto accessor = mReadAccessors.value(key);
+            return accessor(buffer);
+        }
+        return QVariant();
+    }
+    bool hasMapping(const QByteArray &key) const { return mReadAccessors.contains(key); }
+    QList<QByteArray> availableProperties() const { return mReadAccessors.keys(); }
+    void addMapping(const QByteArray &property, const std::function<QVariant(BufferType const *)> &mapping) {
+        mReadAccessors.insert(property, mapping);
+    }
+private:
+    QHash<QByteArray, std::function<QVariant(BufferType const *)> > mReadAccessors;
+};
+
+template<typename BufferBuilder>
+class WritePropertyMapper
+{
+public:
+    virtual void setProperty(const QByteArray &key, const QVariant &value, QList<std::function<void(BufferBuilder &)> > &builderCalls, flatbuffers::FlatBufferBuilder &fbb) const
+    {
+        if (mWriteAccessors.contains(key)) {
+            auto accessor = mWriteAccessors.value(key);
+            builderCalls << accessor(value, fbb);
+        }
+    }
+    bool hasMapping(const QByteArray &key) const { return mWriteAccessors.contains(key); }
+    void addMapping(const QByteArray &property, const std::function<std::function<void(BufferBuilder &)>(const QVariant &, flatbuffers::FlatBufferBuilder &)> &mapping) {
+        mWriteAccessors.insert(property, mapping);
+    }
+private:
+    QHash<QByteArray, std::function<std::function<void(BufferBuilder &)>(const QVariant &, flatbuffers::FlatBufferBuilder &)> > mWriteAccessors;
+};
+