/*

   config.c      -- Part of Chart-generator for the weatherstation

   Copyright (C) 2006 Jan Losinski

   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.

*/

/*
 * Wenn mehr kommentare benoetigt werden:
 * losinski@wh2.tu-dresden.de 
 * */


#include <string.h>
#include <stdlib.h>
#include <stdio.h>

#include "config.h"
#include "definitions.h"
#include "common.h"

/* Funktionsdefinitionen */
static int add_image_cfg(const char *, void *);
 

/* Zuordnung zwischen Schlüsselwörtern in der Config, Der Funktion, die diese auswertet 
 * und dem eld in der Options-Struktur */
static const config_keyword dflt_keywords[] = {
  /* keyword			handler  	 	variable address			default */
  {"fork", 			read_yn,                &(global_opts.fork),         		""},
  {"image_cfg",    		add_image_cfg,          &(global_opts.image_cfg),         	""},
  {"image_cfg_location",	read_str,               &(global_opts.image_cfg_location),    	DEFAULT_PG_HOST},
  {"dflt_image_location",	read_str,               &(global_opts.dflt_image_location),    	DEFAULT_PG_HOST},
  
  {"pg_host",           	read_str,               &(global_opts.pg_host),         	DEFAULT_PG_HOST},
  {"pg_user",           	read_str,               &(global_opts.pg_user),         	DEFAULT_PG_USER},
  {"pg_pass",           	read_str,               &(global_opts.pg_pass),         	DEFAULT_PG_PASS},
  {"pg_database",       	read_str,               &(global_opts.pg_database),     	DEFAULT_PG_DATABASE},
  {"pg_timeout", 		read_str, 		&(global_opts.pg_timeout),		DEFAULT_PG_TIMEOUT},
  {"",				NULL, 	  		NULL,					""}
};


/* Implementierungen */


/* Liest eine Option (line) als String und speichert diese in 
 * dem entsprechendem Feld der Optionen-Struktur (arg) */
int read_str(const char *line, void *arg){
	char **dest = arg;
	if (*dest) free(*dest);
	*dest = strdup(line);
	return 1;
}


/* Interval lesen, indem die Sensoren das letzte mal etwas gesendet haben sollen */
int read_int(const char *line, void *arg){
  int *dest = arg;
  *dest = atoi(line);
  return 1;
}

/* lesen, ob id's aus der Datenbank gelesen werden sollen oder nicht */
int read_yn(const char *line, void *arg){
  char *dest = arg;
  int retval = 1;
  if (!strcasecmp("yes", line))
    *dest = 1;
  else if (!strcasecmp("no", line))
    *dest = 0;
  else retval = 0;
  return retval;
}

/* fuegt eine id zur liste hinzu */
static int add_image_cfg(const char *line, void *arg){
  image_cfg_list_ptr cfg_new, cfg_temp;

  cfg_new = malloc(sizeof(image_cfg_list));
  cfg_new->next = NULL;
  cfg_new->image_cfg_file = strdup(line);

  DEBUGOUT2("add cfg: %s\n", line);

  cfg_temp = *((image_cfg_list_ptr*)arg);
  if (cfg_temp == NULL){
    cfg_temp                    = cfg_new;
    *((image_cfg_list_ptr*)arg) = cfg_temp;
  } else {
    while (cfg_temp->next != NULL){
      cfg_temp = cfg_temp->next;
    }
    cfg_temp->next = cfg_new;
  }
  return 1;
}



/* Liest und verarbeitet die Config-File 
 * der Integer reset gibt an, ob zu begin defaultwerte
 * gesetzt werden sollen oder nicht */
int read_config(char *file, int reset, const config_keyword *keywords){
  FILE *in;						/* File-Handler */
  char buffer[CONFIG_BUFFERSIZE], *token, *line;	/* Puffer zum lesen der config-file (imer 1 Zeile)*/
  char orig[CONFIG_BUFFERSIZE];				/* Originalpuffer zum lesen der config-file, um die Log und debug-ausgabe zu realisieren */
  int i; 						/* Laufvariable */
  int lm = 0; 						/* Zeilen-Nummer */

  if(keywords == NULL)
    keywords = (config_keyword *)dflt_keywords;

  /* Optionen mit default-werten füllen */
  if(reset){
    for (i = 0; keywords[i].keyword[0]; i++)
    //printf("keyword: %s \n",keywords[i].keyword);
      if (keywords[i].def[0])
        keywords[i].handler(keywords[i].def, keywords[i].var);
  }

  /* config-file öffnen */
  if (!(in = fopen(file, "r"))) {
    DEBUGOUT2("Kann Config-File: '%s' nicht öffnen!\n", file);
    return 0;
  }

  /* Datei Zeilenweise lesen */
  while (fgets(buffer, CONFIG_BUFFERSIZE, in)) {
    lm++;

    /* Zeilenvorschübe gegen null-terminierungs-Zeichen ersetzen */
    if (strchr(buffer, '\n')) *(strchr(buffer, '\n')) = '\0';
  
    /* Originlzeile für eventuelle log-, bzw. debug-meldungen */
    strcpy(orig, buffer);
  
    /* Kommentazeichen gegen null-terminierungs-Zeichen ersetzen und damit alles dahinter ignorieren */
    if (strchr(buffer, '#')) *(strchr(buffer, '#')) = '\0';


    if (!(token = strtok(buffer, " \t"))) continue;
    if (!(line = strtok(NULL, ""))) continue;

    /* eat leading whitespace */
    line = line + strspn(line, " \t=");
    /* eat trailing whitespace */
    for (i = strlen(line); i > 0 && isspace(line[i - 1]); i--);
    line[i] = '\0';

    for (i = 0; keywords[i].keyword[0]; i++){
      if (!strcasecmp(token, keywords[i].keyword)){
        if (!keywords[i].handler(line, keywords[i].var)) {
	  /* Fehler ins Logfile schreiben */
	  DEBUGOUT4("Kann '%s' nicht Parsen (%s:%d)!\n", orig, file, lm);
          /* reset back to the default value */
          keywords[i].handler(keywords[i].def, keywords[i].var);
        }
      }
    }
  }
  fclose(in);
  return 1;
}