/* interp.c : interpreter interface using Lua */
/*
 * Copyright 2006 Jon Mayo and XXX
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions: The above copyright
 * notice and this permission notice shall be included in all copies or
 * substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

/* You can download Lua at:
 *      http://www.lua.org/
 *      http://www.tecgraf.puc-rio.br/lua/
 */
#include <stdio.h>
#include <string.h>
#include <lua.h>
#include <lualib.h>
#include <lauxlib.h>

#include "interp.h"


/** lua functions we're going to define **/
static int echo(lua_State *L)
{
	int nr_arg;
	int i;
	
	nr_arg=lua_gettop(L);
	for(i=1;i<=nr_arg;i++) {
		if(lua_isstring(L,i)) {
			printf("%s",lua_tostring(L,i));
		} else {
			printf("%s:%p",lua_typename(L,lua_type(L,i)),lua_topointer(L,i));
		}
	}
	printf("\n");
	return 0; /* success */
}

static lua_State *create_state()
{
	lua_State *L;	
	L=lua_open();
	if(L) {
		luaopen_base(L); 
		luaopen_table(L); 
		luaopen_string(L); 
		/*
		luaopen_io(L); 
		luaopen_loadlib(L); 
		*/
		lua_register(L,"echo",echo);
	}
	return L;
}

int interpret_file(const char *filename)
{
	int result;
	lua_State *L;
	FILE *f;
	
	f=fopen(filename, "r");
	if(!f) { 
		perror(filename);
		return 0;
	}
	L=create_state();
	result=luaL_loadfile(L, filename);

	if(!result) {
		result = lua_pcall(L, 0, LUA_MULTRET, 0);
		if(result) {
			fprintf(stderr, "%s:%s\n", filename, lua_tostring(L, -1));
			lua_pop(L, 1);
		}
	} else {
		fprintf(stderr, "%s:%s\n", filename, lua_tostring(L, -1));
		lua_pop(L, 1);
	}

	lua_close(L);
	fclose(f);
	return result;
}

int interpret(const char *name, const char *data)
{
	int data_len;
	int error;
	lua_State *L;

	L=create_state();
	data_len=strlen(data);
	error=luaL_loadbuffer(L,data,data_len,name) || lua_pcall(L, 0, 0, 0);
	if(error) {
		fprintf(stderr, "%s", lua_tostring(L, -1));
		lua_pop(L, 1);
	}
	lua_close(L);
	return error;
}