/*
  config.c  -  Lumiera configuration system

  Copyright (C)         Lumiera.org
    2008,               Christian Thaeter <ct@pipapo.org>

  This program 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.

  This program 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 this program; if not, write to the Free Software
  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

//TODO: Support library includes//
#include "lib/safeclib.h"


//TODO: Lumiera header includes//
#include "backend/config.h"

//TODO: internal/static forward declarations//


//TODO: System includes//
#include <stdint.h>
#include <stdlib.h>

/**
 * @file
 *
 */

NOBUG_DEFINE_FLAG_PARENT (config_all, backend);
NOBUG_DEFINE_FLAG_PARENT (config, config_all);
NOBUG_DEFINE_FLAG_PARENT (config_typed, config_all);
NOBUG_DEFINE_FLAG_PARENT (config_file, config_all);

LUMIERA_ERROR_DEFINE (CONFIG_SYNTAX, "syntax error in configfile");
LUMIERA_ERROR_DEFINE (CONFIG_SYNTAX_KEY, "syntax error in key");
LUMIERA_ERROR_DEFINE (CONFIG_TYPE, "value has wrong type");
LUMIERA_ERROR_DEFINE (CONFIG_NO_ENTRY, "no configuration entry");
LUMIERA_ERROR_DEFINE (CONFIG_DEFAULT, "illegal default value");


/* singleton config */
LumieraConfig lumiera_global_config = NULL;


int
lumiera_config_init (const char* path)
{
  TRACE (config);
  REQUIRE (!lumiera_global_config, "Configuration subsystem already initialized");
  REQUIRE (path);

  NOBUG_INIT_FLAG (config_all);
  NOBUG_INIT_FLAG (config);
  NOBUG_INIT_FLAG (config_typed);
  NOBUG_INIT_FLAG (config_file);

  lumiera_global_config = lumiera_malloc (sizeof (*lumiera_global_config));
  lumiera_global_config->path = lumiera_strndup (path, SIZE_MAX);
  lumiera_rwlock_init (&lumiera_global_config->lock);
  RESOURCE_ANNOUNCE (config, "rwlock", "config", lumiera_global_config, lumiera_global_config->rh);

  return 0;
}


void
lumiera_config_destroy ()
{
  TRACE (config);
  if (lumiera_global_config)
    {
      RESOURCE_FORGET (config, lumiera_global_config->rh);
      lumiera_rwlock_destroy (&lumiera_global_config->lock);
      lumiera_free (lumiera_global_config->path);
      lumiera_free (lumiera_global_config);
      lumiera_global_config = NULL;
    }
  else
    WARN (config, "Tried to destroy non initialized config subsystem");
}


int
lumiera_config_load (const char* file)
{
  TRACE (config);
  UNIMPLEMENTED();
  return -1;
}


int
lumiera_config_save ()
{
  TRACE (config);
  UNIMPLEMENTED();
  return -1;
}


int
lumiera_config_purge (const char* filename)
{
  TRACE (config);

  UNIMPLEMENTED();
  return -1;
}


int
lumiera_config_get (const char* key, const char** value)
{
  TRACE (config);
  REQUIRE (key);
  REQUIRE (value);

  int ret = -1;

  /* we translate the key for the env var override by making it uppercase and replace . and - with _,
   as side effect, this also checks the key syntax */
  char* tr_key = lumiera_tmpbuf_tr (key,
                                    "abcdefghijklmnopqrstuvqxyz0123456789_.",
                                    "ABCDEFGHIJKLMNOPQRSTUVQXYZ0123456789__",
                                    NULL);
  if (!tr_key)
    {
      LUMIERA_ERROR_SET (config, CONFIG_SYNTAX_KEY);
    }
  else
    {
      char* env = lumiera_tmpbuf_snprintf (2048, "LUMIERA_%s", tr_key);

      *value = getenv(env);
      if (*value)
        {
          ret = 0;
          NOTICE (config, "envvar override for config %s = %s", env, *value);
        }
      else
        {
          TODO ("lookup key");
          ret = 0; /* assume that the lockup worked for now, value is still NULL, just no error set */
        }
    }

  return ret;
}


int
lumiera_config_set (const char* key, const char* value)
{
  TRACE (config);
  UNIMPLEMENTED();
  return -1;
}


int
lumiera_config_reset (const char* key)
{
  TRACE (config);
  UNIMPLEMENTED();
  return -1;
}


int
lumiera_config_info (const char* key, const char** filename, unsigned* line)
{
  TRACE (config);
  UNIMPLEMENTED();
  return -1;
}

/*
// Local Variables:
// mode: C
// c-file-style: "gnu"
// indent-tabs-mode: nil
// End:
*/