/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
 *            luaformatmapperutils.cc
 *
 *  Mon Nov  3 08:46:51 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 "luaformatmapperutils.h"
#include "luaformatmapper.h"

#include <string>
#include <vector>

std::vector< void * > pointers;

#define GLOBAL_PREFIX "magic_global_"

void *getGlobal(lua_State *L, const char *name)
{
  unsigned int top;
  unsigned int index;

  std::string var = std::string(GLOBAL_PREFIX) + name;

  lua_getfield(L, LUA_GLOBALSINDEX, var.c_str()); 
  top = lua_gettop(L);
  index = lua_tointeger(L, top);

  return pointers.at(index);
}

void setGlobal(lua_State *L, const char *name, void *p)
{
  // Put the value of this in the globals
  char value_of_this[256];

  std::string val = std::string(GLOBAL_PREFIX) + name;

  pointers.push_back(p);
  unsigned int index = pointers.size() - 1;

  sprintf(value_of_this, "%s = %u\n", val.c_str(), index);
  int s = luaL_loadstring(L, value_of_this);
  switch(s) {
  case 0: //no errors;
    break;
  case LUA_ERRSYNTAX: //syntax error during pre-compilation;
  case LUA_ERRMEM: //memory allocation error.
    fprintf(stderr, "Error: %s\n", lua_tostring(L, lua_gettop(L)));
  default:
    fprintf(stderr, "Unknown return value of luaL_loadstring.\n");
  }

  // Run program (init)
  s = lua_pcall(L, 0, LUA_MULTRET, 0);
  // Check for errors
  switch(s) {
  case 0: // Success
    break;
  case LUA_ERRRUN:// a runtime error.
  case LUA_ERRMEM:// memory allocation error.
    // For such errors, Lua does not call the error handler function.
  case LUA_ERRERR:// error while running the error handler function.
    fprintf(stderr, "Error: %s\n", lua_tostring(L, lua_gettop(L)));
    break;
  default:
    fprintf(stderr, "Error: Unknown return value of lua_pcall.\n");
    break;
  }
}

typedef enum {
  MLTT_VALUE,
  MLTT_TEXT,
  MLTT_ENDOFITEM, // newline
  MLTT_UNDEFINED
} mltokentype_t;

typedef struct {
  mltokentype_t type;
  std::string name;
  std::string value;
} mltoken_t;

std::vector< mltoken_t > mltokenize(std::string mlvalue)
{
  std::vector< mltoken_t > tokens;
  /*
  mltoken_t token;
  token = MLTT_UNDEFINED;
  for(size_t i = 0; i < mlvalue.length(); i++) {
    switch(mlvalue[i]) {
    case '$':
    case '[':
    case ']':
    case '\n':
    default:
    }
  }
  */
  {
    mltoken_t token;
    token.type = MLTT_TEXT;
    token.value = "noget tekst ";
    tokens.push_back(token);
  }

  {
    mltoken_t token;
    token.type = MLTT_VALUE;
    token.name = "myname";
    token.value = "myvalue";
    tokens.push_back(token);
  }

  {
    mltoken_t token;
    token.type = MLTT_TEXT;
    token.value = " noget mere tekst";
    tokens.push_back(token);
  }

  {
    mltoken_t token;
    token.type = MLTT_ENDOFITEM;
    token.value = "\n";
    tokens.push_back(token);
  }

  // en entry mere...
  {
    mltoken_t token;
    token.type = MLTT_TEXT;
    token.value = "yet another ";
    tokens.push_back(token);
  }

  {
    mltoken_t token;
    token.type = MLTT_VALUE;
    token.name = "myname";
    token.value = "another value";
    tokens.push_back(token);
  }

  {
    mltoken_t token;
    token.type = MLTT_TEXT;
    token.value = " and thats final!";
    tokens.push_back(token);
  }

  {
    mltoken_t token;
    token.type = MLTT_ENDOFITEM;
    token.value = "\n";
    tokens.push_back(token);
  }

  return tokens;
}

typedef struct {
  std::string prefix;
  std::string postfix;
} transform_params_t;

std::map< std::string, transform_params_t > transforms;

/**
 * Args: mlvalue, bullet, usetext, name1, prefix1, postfix1, name2, prefix2, postfix2, ...
 * Iterates list items, prepends bullet, and replaces all name/value pairs with
 * corresponding prefix/value/postfix.
 */
int printfmlval(lua_State *L)
{
  int n = lua_gettop(L); // number of arguments
  if(n < 3 || (n - 3) % 3 != 0) {
    char errstr[512];
    sprintf(errstr, "Minimum number of args expected 3, got %d", n);
    fprintf(stderr, errstr);
    lua_pushstring(L, errstr);
    lua_error(L);
    return 0;
  }

  std::string mlvalue = lua_tostring(L, lua_gettop(L) - (n - 1));
  std::string bullet = lua_tostring(L, lua_gettop(L) - (n - 2));
  bool usetext = lua_toboolean(L, lua_gettop(L) - (n - 3));
  
  printf("[%s], [%s], [%d]\n", mlvalue.c_str(), bullet.c_str(), usetext); fflush(stdout);

  // Read in the (prefix, name, postfix) 3-tuples
  int m = 4;
  while(m < lua_gettop(L)) {
    
    printf("!\n"); fflush(stdout);

    transform_params_t p;
    p.prefix = lua_tostring(L, lua_gettop(L) - (n - m));
    std::string name = lua_tostring(L, lua_gettop(L) - (n - (m + 1)));
    p.postfix = lua_tostring(L, lua_gettop(L) - (n - (m + 2)));

    printf("[%s], [%s], [%s]\n", p.prefix.c_str(), name.c_str(), p.postfix.c_str()); fflush(stdout);

    transforms[name] = p;
    
    m += 3;
  }

  LUAFormatMapper *lfm = (LUAFormatMapper*)getGlobal(L, "LUAFormatMapper");

  mltokentype_t lasttype = MLTT_ENDOFITEM;
  std::vector< mltoken_t > tokens = mltokenize(mlvalue);
  std::vector< mltoken_t >::iterator i = tokens.begin();
  while(i != tokens.end()) {
    if(lasttype == MLTT_ENDOFITEM) lfm->bufferoutput(bullet);

    switch(i->type) {
    case MLTT_VALUE:
      lfm->bufferoutput(transforms[i->name].prefix);
      lfm->bufferoutput(i->value);
      lfm->bufferoutput(transforms[i->name].postfix);
      break;

    case MLTT_TEXT:
      if(usetext) lfm->bufferoutput(i->value);
      break;

    case MLTT_ENDOFITEM:
      if(usetext) lfm->bufferoutput(i->value);
      break;

    case MLTT_UNDEFINED:
      // Undefined
      break;
    }

    lasttype = i->type;
    i++;
  }

  return 0;
}


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

  std::string value = lua_tostring(L, lua_gettop(L));

  LUAFormatMapper *lfm = (LUAFormatMapper*)getGlobal(L, "LUAFormatMapper");

  lfm->bufferoutput(value);

  return 0;
}

/*
int pg_query(lua_State *L)
{
  int n = lua_gettop(L); // number of arguments
  if(n != 2) {
    char errstr[512];
    sprintf(errstr, "Number of args expected 2, got %d", n);
    fprintf(stderr, errstr);
    lua_pushstring(L, errstr);
    lua_error(L);
    return 0;
  }
  
  std::string query = lua_tostring(L, lua_gettop(L));
  unsigned int pg = lua_tointeger(L, lua_gettop(L) - 1);

  printf("query [%s]\n", query.c_str());

  //  lua_createtable(L, 0, 1);
  //  lua_pushinteger(L, 41);
  //  lua_rawseti(L, -2, 1);
  //  lua_setfenv(L, -2);

  lua_pushinteger(L, 42);
  lua_pushinteger(L, 41);
  lua_rawset(L, -3);

  return 1;
}
*/

void preload_formatutils(lua_State *L)
{
  lua_register(L, "printval", printval);
  lua_register(L, "printfmlval", printfmlval);
}