moved Rtti from managed to common folder, added Function header

1 files changed, 149 insertions, 0 deletions

diff --git a/src/core/common/Function.hpp b/src/core/common/Function.hpp
new file mode 100644
index 0000000..3a0ed9f
--- /dev/null
+++ b/src/core/common/Function.hpp
@@ -0,0 +1,149 @@
+/*
+    Ousía
+    Copyright (C) 2014, 2015  Benjamin Paaßen, Andreas Stöckel
+
+    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 3 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, see <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @file Function.hpp
+ *
+ * Contains the definition of a Function class used to describe both methods and
+ * functions in the host code and functions in the script code.
+ *
+ * @author Andreas Stöckel (astoecke@techfak.uni-bielefeld.de)
+ */
+
+#ifndef _OUSIA_FUNCTION_HPP_
+#define _OUSIA_FUNCTION_HPP_
+
+#include <cassert>
+#include <memory>
+
+#include "Variant.hpp"
+
+namespace ousia {
+
+/**
+ * The AbstractFunction interface defines all the methods needed to represent
+ * a reference at a generic function object. Function objects can be called
+ * using the call function in which an array of Variant is supplied to the
+ * function and a Variant is returned to the caller.
+ */
+class AbstractFunction {
+private:
+	/**
+	 * Private, non-callable constructor.
+	 */
+	AbstractFunction(){};
+
+	/* No copy constructor */
+	AbstractFunction(const AbstractFunction &) = delete;
+
+	/* No move constructor */
+	AbstractFunction(AbstractFunction &&) = delete;
+
+public:
+	/**
+	 * Pure virtual method used to create a copy of the AbstractFunction
+	 * object.
+	 *
+	 * @return a unique pointer pointing at a copy of the AbstractFunction
+	 * object.
+	 */
+	virtual std::unique_ptr<AbstractFunction> clone() const = 0;
+
+	/**
+	 * Virtual destructor.
+	 */
+	virtual ~AbstractFunction() {}
+
+	/**
+	 * Abstract function which is meant to call the underlying function (be it
+	 * a host or a script function) with the given arguments.
+	 *
+	 * @param args is a vector containing all arguments that shall be passed to
+	 * the function.
+	 * @return a Variant containing the return value.
+	 */
+	virtual Variant call(const Variant::arrayType &args = Variant::arrayType{},
+	                     void *thisRef = nullptr) const = 0;
+};
+
+/**
+ * The Method class refers to a method in the C++ code, belonging to an object
+ * of a certain type T.
+ *
+ * @tparam T is the type of the method that should be called.
+ */
+template <class T>
+class Method : public AbstractFunction {
+public:
+	/**
+	 * Type of the Callback function that is being called by the "call"
+	 * function.
+	 *
+	 * @param args contains the input arguments that were passed to the
+	 * function.
+	 * @param thisRef is a pointer pointing at an instance of type T.
+	 * @return the return value of the function as Variant instance.
+	 */
+	using Callback = Variant (*)(const Variant::arrayType &args, T *thisRef);
+
+private:
+	/**
+	 * Pointer at the actual C++ method being called.
+	 */
+	const Callback method;
+
+public:
+	/**
+	 * Constructor of the Method class.
+	 *
+	 * @param method is a pointer at the C++ function that should be called.
+	 */
+	Method(Callback method) : method(method){};
+
+	/**
+	 * Creates a copy of this Method object.
+	 */
+	std::unique_ptr<AbstractFunction> clone() const override
+	{
+		return std::unique_ptr<AbstractFunction>{new Method<T>(method)};
+	}
+
+	/**
+	 * Calls the underlying method.
+	 *
+	 * @param args is a vector containing all arguments that shouild be passed
+	 * to the method.
+	 * @return a Variant containing the return value.
+	 */
+	Variant call(const Variant::arrayType &args = Variant::arrayType{},
+	             void *thisRef = nullptr) const override
+	{
+		// Dynamically cast thisRef to the given type
+		T *tRef = dynamic_cast<T>(thisRef);
+
+		// Make sure the cast is successfull
+		assert(tRef != nullptr);
+
+		// Call the method
+		return method(args, tRef);
+	}
+};
+}
+
+#endif /* _OUSIA_FUNCTION_HPP_ */
+