//********************************** Banshee Engine (www.banshee3d.com) **************************************************//
//**************** Copyright (c) 2016 Marko Pintera (marko.pintera@gmail.com). All rights reserved. **********************//
#pragma once

#include "BsMonoPrerequisites.h"

namespace bs
{
	/** @addtogroup Mono
	 *  @{
	 */

	/**
	 * Encapsulates information about a single Mono (managed) method belonging to some managed class. This object also
	 * allows you to invoke the method.
	 */
	class BS_MONO_EXPORT MonoMethod
	{
	public:
		~MonoMethod();

		/**
		 * Invokes the method on the provided object instance. This does not respect polymorphism and will invoke the exact
		 * method of the class this object was retrieved from. Use invokeVirtual() if you need polymorphism.
		 *
		 * @param[in]	instance	Instance of the object to invoke the method on. Can be null for static methods.
		 * @param[in]	params		Array of parameters to pass to the method. Caller must ensure they match method 
		 *							parameter count and type. For value types parameters should be pointers to the 
		 *							values and for reference types they should be pointers to MonoObject.
		 * @return					A boxed return value, or null if method has no return value.
		 */
		MonoObject* invoke(MonoObject* instance, void** params);

		/**
		 * Invokes the method on the provided object instance. If the instance has an override of this method it will be
		 * called.
		 *
		 * @param[in]	instance	Instance of the object to invoke the method on.
		 * @param[in]	params		Array of parameters to pass to the method. Caller must ensure they match method 
		 *							parameter count and type. For value types parameters should be pointers to the 
		 *							values and for reference types they should be pointers to MonoObject.
		 * @return					A boxed return value, or null if method has no return value.
		 */
		MonoObject* invokeVirtual(MonoObject* instance, void** params);

		/**
		 * Gets a thunk for this method. A thunk is a C++ like function pointer that you can use for calling the method.
		 *
		 * @note	This is the fastest way of calling managed code.
		 */
		void* getThunk() const;

		/**	Returns the name of the method. */
		String getName() const;

		/** Returns the type of the return value. Returns null if method has no return value. */
		MonoClass* getReturnType() const;

		/**	Returns the number of parameters the method expects. */
		UINT32 getNumParameters() const;

		/**	Returns the type of the method parameter at the specified index. */
		MonoClass* getParameterType(UINT32 paramIdx) const;

		/**	Returns true if the method doesn't require a class instance. */
		bool isStatic() const;

		/**	Checks if method has an attribute of the specified type. */
		 bool hasAttribute(MonoClass* monoClass) const;

		/**
		 * Returns an instance of an attribute of the specified type. Returns null if the method doesn't have such an
		 * attribute.
		 */
		MonoObject* getAttribute(MonoClass* monoClass) const;

		/**	Returns method visibility in the class. */
		MonoMemberVisibility getVisibility();

	private:
		friend class MonoClass;
		friend class MonoProperty;

		MonoMethod(::MonoMethod* method);

		void cacheSignature() const;

		::MonoMethod* mMethod;

		mutable MonoClass* mCachedReturnType;
		mutable MonoClass** mCachedParameters;
		mutable UINT32 mCachedNumParameters;
		mutable bool mIsStatic;
		mutable bool mHasCachedSignature;
	};

	/** @} */
}