/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
 *            luaquerymapper.cc
 *
 *  Mon May  5 15:43:52 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 "luaquerymapper.h"

#include <sstream>

static std::string loadresultstring(QueryResult &res, std::string group = "")
{
  std::string s;
  std::stringstream timestamp; timestamp << res.timestamp;

  std::map< std::string, std::string >::iterator v = res.values.begin();
  while(v != res.values.end()) {
    s += group + (*v).first + " = {}\n";
    s += group + (*v).first + ".value = \"" + (*v).second + "\"\n";
    s += group + (*v).first + ".timestamp = " + timestamp.str() + "\n";
    v++;
  }

  std::map< std::string, QueryResult >::iterator g = res.groups.begin();
  while(g != res.groups.end()) {
    s += group + (*g).first + " = {}\n";
    s += loadresultstring((*g).second, group + (*g).first + ".");
    g++;
  }

  return s;
}

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

  luaL_openlibs(L);

  // FIXME: Insert these variables directly into the LUA stack instead of parsing them.
  std::string preload = loadresultstring(res);

  int s = luaL_loadbuffer(L, preload.c_str(), preload.size(), "preload");
  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 program (init)
  lua_pcall(L, 0, LUA_MULTRET, 0);
}

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

Value LUAQueryMapper::map(const std::string &mapper)
{
  int s = luaL_loadbuffer(L, mapper.c_str(), mapper.size(), "mapper");
  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);

  Value v;
  
  v.timestamp = lua_tointeger(L, lua_gettop(L));
  lua_pop(L, 1);
  v.value = lua_tostring(L, lua_gettop(L));
  lua_pop(L, 1);

  return v;
}

#ifdef TEST_LUAQUERYMAPPER

#include "queryhandler.h"
#include "queryparser.h"

int main()
{
  TCPSocket s;
  s.connect("localhost", 11108);

  QueryHandler qh(&s, "2003791613");

  Query q1;
  q1.attributes["device_id"] = "lensmeter";
  q1.attributes["device_type"] = "lensmeter";

  std::string res = qh.exec();
  
  printf("%s\n", res.c_str());

  QueryParser e(res);
  e.parse();

  printf("%s\n", loadresultstring(e.result).c_str());

  LUAQueryMapper mapper(e.result);

  std::string luamap = "return right.sphere";
  printf("%s : %s\n", luamap.c_str(), mapper.map(luamap).c_str());

  luamap = "return math.sin(right.cyl) * 2";
  printf("%s : %s\n", luamap.c_str(), mapper.map(luamap).c_str());

  return 0;
}

#endif/*TEST_LUAQUERYMAPPER*/