/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
 *            lua.cc
 *
 *  Thu May 29 16:30:50 CEST 2008
 *  Copyright 2008 Bent Bisballe Nyeng
 *  deva@aasimon.org
 ****************************************************************************/

/*
 *  This file is part of Pracro.
 *
 *  Pracro 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.
 *
 *  Pracro 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 Pracro; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 */
#include "lua.h"

#include "macrowindow.h"

#define GLOBAL_POINTER "_pracroGlobalLUAObjectPointer"

LUA *glua;

static int _getValue(lua_State *L)
{
  int n = lua_gettop(L); // number of arguments
  if(n != 1) {
    char errstr[512];
    sprintf(errstr, "Number of args expected 0, got %d", n);
    fprintf(stderr, errstr);
    lua_pushstring(L, errstr);
    lua_error(L);
    return 1;
  }

  QString name = lua_tostring(L, lua_gettop(L));

  lua_getglobal(L, GLOBAL_POINTER);
  LUA *lua = glua;//(LUA*)lua_touserdata(L, 1);

  if(!lua) {
    printf("No LUA pointer!\n");
    lua_pushstring(L, "No LUA pointer!");
    lua_error(L);
    return 1;
  }

  QString value = lua->getValue(name);
  lua_pushstring(L, value.toStdString().c_str());

  return 1;
}

static int _setValue(lua_State *L)
{
  int n = lua_gettop(L); // number of arguments
  if(n != 2) {
    char errstr[512];
    sprintf(errstr, "Number of args expected 0, got %d", n);
    fprintf(stderr, errstr);
    lua_pushstring(L, errstr);
    lua_error(L);
    return 0;
  }

  QString value = lua_tostring(L, lua_gettop(L));
  lua_pop(L, 1);
  QString name = lua_tostring(L, lua_gettop(L));
  lua_pop(L, 1);

  lua_getglobal(L, GLOBAL_POINTER);
  LUA *lua = glua;//(LUA*)lua_touserdata(L, 1);

  if(!lua) {
    printf("No LUA pointer!\n");
    lua_pushstring(L, "No LUA pointer!");
    lua_error(L);
    return 1;
  }

  lua->setValue(name, value);

  return 0;
}

LUA::LUA(MacroWindow *macrowindow)
{
  glua = this;
  this->macrowindow = macrowindow;

  L = luaL_newstate();
  if(L == NULL) {
    //    throw LUADataParserException("Could not create LUA state.");
  }

  luaL_openlibs(L);               

  lua_pushlightuserdata(L, this); // Push the pointer to 'this' instance
  lua_setglobal(L, GLOBAL_POINTER); // Assign it to a global lua var.

  lua_register(L, "getValue", _getValue);
  lua_register(L, "setValue", _setValue);
}

LUA::~LUA()
{
  lua_close(L);
}

QString LUA::getValue(QString name)
{
  return macrowindow->getValue(name);
}

void LUA::setValue(QString name, QString value)
{
  macrowindow->setValue(name, value);
}

bool LUA::run(QString program, QString value)
{
  if(macrowindow->luaprograms.contains(program) == false) return false;

  QString luacode = "value = " + value + "\n";
  QString luaprogram = macrowindow->luaprograms.value(program);
  luacode += luaprogram;
    
  int s = luaL_loadbuffer(L,
                          luacode.toStdString().c_str(),
                          luacode.size(),
                          program.toStdString().c_str());
  switch(s) {
  case 0: //no errors;
    break;
  case LUA_ERRSYNTAX: //syntax error during pre-compilation;
  case LUA_ERRMEM: //memory allocation error.
  case LUA_ERRFILE: //cannot open/read the file.
    //throw LUADataParserException(lua_tostring(L, lua_gettop(L)));
    break;
  default:
    //throw LUADataParserException("Unknown return value of luaL_loadfile.");
    break;
  }

  // Run the loaded code
  lua_pcall(L, 0, LUA_MULTRET, 0);

  bool res = lua_toboolean(L, lua_gettop(L));
  lua_pop(L, 1);

  return res;
}