/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
 *            luaformatmapper.cc
 *
 *  Wed Oct 29 16:02:03 CET 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 "luaformatmapper.h"

#include <sstream>

#include "exception.h"

#include "luaformatmapperutils.h"
/*
static std::string loadresultstring(Fields &fields)
{
  std::string s;

  Fields::iterator v = fields.begin();
  while(v != fields.end()) {
    lua_pushstring(L, v->second); // Push the pointer to 'this' instance
    lua_setglobal(L, v->first); // Assign it to a global lua var.
    //    s += (*v).first + " = \"" + (*v).second + "\"\n";
    v++;
  }

  return s;
}
*/
LUAFormatMapper::LUAFormatMapper(Fields &fields)
{
  L = luaL_newstate();
  if(L == NULL) {
    error("Could not create LUA state.");
    return;
  }

  luaL_openlibs(L);

  setGlobal(L, "LUAFormatMapper", this);
  preload_formatutils(L);

  Fields::iterator v = fields.begin();
  while(v != fields.end()) {
    lua_pushstring(L, v->second.c_str()); // Push the pointer to 'this' instance
    lua_setglobal(L, v->first.c_str()); // Assign it to a global lua var.
    v++;
  }
  /*
  std::string preload = loadresultstring(fields);

  if(luaL_loadbuffer(L, preload.c_str(), preload.size(), "preload")) {
    error(lua_tostring(L, lua_gettop(L)));
    return;
  }

  // Run program (init)
  if(lua_pcall(L, 0, LUA_MULTRET, 0)) {
    error(lua_tostring(L, lua_gettop(L)));
    return;
  }
  */
  clean_top = lua_gettop(L);
}

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

std::string LUAFormatMapper::map(const std::string &mapper)
{
  output = "";

  if(L == NULL) {
    error("LUA state not initialized!");
    return output;
  }

  if(mapper == "") {
    error("Empty LUA mapper detected in " + mapper);
    return output;
  }

  // Load the mapper
  if(luaL_loadbuffer(L, mapper.c_str(), mapper.size(), "mapper")) {
    error(lua_tostring(L, lua_gettop(L)) + std::string(" in ") + mapper);
    return output;
  }

  // Run the loaded code
  if(lua_pcall(L, 0, LUA_MULTRET, 0)) {
    error(lua_tostring(L, lua_gettop(L)) + std::string(" in ") + mapper);
    return output;
  }

  // Check if app messed up the stack.
  if(lua_gettop(L) != clean_top) {
    error("Wrong number of return values in " + mapper);
    lua_pop(L, lua_gettop(L) - clean_top);
    return output;
  }

  //  output = lua_tostring(L, lua_gettop(L));
  //  lua_pop(L, 1);

  return output;
}

void LUAFormatMapper::error(std::string message)
{
  throw Exception("ERROR in LUAFormatMapper: " + message);
}

void LUAFormatMapper::bufferoutput(std::string value)
{
  output += value;
}