/*
 * LuaHelper.cs
 * Authors: Adam Nabinger
 * Copyright (c) 2007-2008 Cornell University

 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*/

using System.IO;
using LuaInterface;
using System;
using System.Reflection;


public static class LuaHelper
{
	private const string LuaFile = @"lua51.dll";

	static LuaHelper()
	{
		if (!File.Exists(LuaFile))
		{
			using (FileStream output = new FileStream(LuaFile, FileMode.CreateNew, FileAccess.Write, FileShare.Read))
			using (BinaryWriter writer = new BinaryWriter(output))
			{
				writer.Write(LuaAccess.Resource.lua51);
			}
		}
	}

	public static Lua GetNewVM()
	{
		return new Lua();
	}

	public static void RegisterAllFunctions(Lua VM, object obj)
	{
		foreach (MethodInfo info in obj.GetType().GetMethods())
		{
			VM.RegisterFunction(info.Name, obj, info);
		}
	}

	public static void RegisterLuaCallbacks(Lua VM, object obj)
	{
		Type type = obj.GetType();

		foreach (MethodInfo info in type.GetMethods())
		{
			foreach (Attribute attribute in Attribute.GetCustomAttributes(info))
			{
				LuaCallback luaCallback = attribute as LuaCallback;
				if (luaCallback != null)
				{
					string funcName = luaCallback.GetFunctionName();
					string[] funcParams = luaCallback.GetFunctionParameters();

					ParameterInfo[] paramInfo = info.GetParameters();

					if (funcParams != null && (funcParams.Length != paramInfo.Length))
					{
						System.Diagnostics.Debug.Assert(false, "The function " + funcName + " has an LuaCallback attribute whose parameters do not match the C# function.");

						break;
					}

					VM.RegisterFunction(funcName, obj, info);
				}
			}
		}
	}
}