/*
 *  Smart Auto Replier (SAR) - auto replier plugin for Miranda IM
 *
 *  Copyright (C) 2004 - 2012 by Volodymyr M. Shcherbyna <volodymyr@shcherbyna.com>
 *
 *  This code is inspired by article of RichardS at http://www.codeproject.com/Articles/11508/Integrating-Lua-into-C
 *
 *      This file is part of SAR.
 *
 *  SAR 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.
 *
 *  SAR 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 SAR.  If not, see <http://www.gnu.org/licenses/>.
*/

#pragma once

#include "luainc.h"

class CLuaBridge
{
public:
	CLuaBridge(void);
	~CLuaBridge(void);

public:
	static int LuaDebugMessage(lua_State * pContext);
	static void HandleLuaAsssert(lua_State * pContext);

	bool RunScript(const char *szScript, size_t nLength, const char *szFuncName = NULL);	
	bool ExecuteFunction(int nArgs, int nReturns  = 0);
	operator lua_State *();

protected:
	lua_State *m_pLuaContext;
};

class CLuaStack
{
public:
	CLuaStack(CLuaBridge & luaBridge) : m_pState(NULL), m_nTopIndex(0)
	{
		m_pState	 = (lua_State*)luaBridge;
		m_nTopIndex	 = lua_gettop(m_pState);
	}

	virtual ~CLuaStack()
	{
		lua_settop(m_pState, m_nTopIndex);
	}

protected:

	lua_State *m_pState;
	int m_nTopIndex;
};

class CLuaTableThis
{
public:
	CLuaTableThis(CLuaBridge & luaBridge, int nRef) : m_nOldRef(0), m_luaBridge(luaBridge)
	{
		lua_State *state = (lua_State*)m_luaBridge;

		lua_getglobal(state, "this");
		m_nOldRef = luaL_ref(state, LUA_REGISTRYINDEX);

		lua_rawgeti(state, LUA_REGISTRYINDEX, nRef);
		lua_setglobal(state, "this");
	}

	virtual ~CLuaTableThis()
	{
		lua_State *state = (lua_State*)m_luaBridge;

		if (m_nOldRef > 0)
		{
			lua_rawgeti(state, LUA_REGISTRYINDEX, m_nOldRef);
			lua_setglobal (state, "this");
			luaL_unref(state, LUA_REGISTRYINDEX, m_nOldRef);
		}
	}

protected:
   int m_nOldRef;
   CLuaBridge & m_luaBridge;
};