/*

   chart.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.

*/

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <errno.h>
#include <signal.h>
#include <string.h>

#include "definitions.h"
#include "config.h"
#include "chart.h"
#include "drawing/process_image.h"

static int walk_image_cfg_list();
static void wait_for_childs();
static void exit_sig_handler(int); 

config global_opts;



static int walk_image_cfg_list(){
  int has_forked             = 0;
  pid_t pid                  = 0;
  image_cfg_list_ptr tmp_ptr = global_opts.image_cfg;

  for(; tmp_ptr; tmp_ptr = tmp_ptr->next){
    if(global_opts.fork){
      if((pid = fork()) == 0){
	process_image(tmp_ptr->image_cfg_file);
	exit(EXIT_SUCCESS);
      } 
      else if (pid == -1){
	exit_error(ERROR_FORK);
      } 
      has_forked++;
      DEBUGOUT2("Prozess %d angelegt\n",pid);
    } else {
      process_image(tmp_ptr->image_cfg_file);
    }
  }
  return has_forked;
}

static void wait_for_childs(){
  int ret_val;
  pid_t pid;
  while((pid = wait(&ret_val)) != -1){
    DEBUGOUT2("Prozess %d beendet\n", pid);
  }
}


int main(int argc, char *argv[]){
  DEBUGOUT1("Programm gestartet\n");

  if(signal(SIGABRT, exit_sig_handler) == SIG_ERR)
    exit_error(ERROR_SEIINST);
  DEBUGOUT1("Signalhandler zum beenden per SIGABRT installiert\n");
  if(signal(SIGINT, exit_sig_handler) == SIG_ERR)
    exit_error(ERROR_SEIINST);
  DEBUGOUT1("Signalhandler zum beenden per SIGINT installiert\n");
  if(signal(SIGQUIT, exit_sig_handler) == SIG_ERR)
    exit_error(ERROR_SEIINST);
  DEBUGOUT1("Signalhandler zum beenden per SIGQUIT installiert\n");
  if(signal(SIGTERM, exit_sig_handler) == SIG_ERR)
    exit_error(ERROR_SEIINST);
  DEBUGOUT1("Signalhandler zum beenden per SIGTERM installiert\n");

  read_config(DEFAULT_CONFIG_FILE, 1);

  /* Debug-Ausgaben, um zu sehen, ob die Optionen richtig gesetzt werden */
  DEBUGOUT1("\nOptionen:\n");
  DEBUGOUT2("  cfg_location = %s\n", global_opts.image_cfg_location);
  DEBUGOUT2("  fork         = %i\n", global_opts.fork);

  DEBUGOUT1("\nPostgres:\n");
  DEBUGOUT2("  Host:     =  %s\n",global_opts.pg_host);
  DEBUGOUT2("  User:     =  %s\n",global_opts.pg_user);
  DEBUGOUT2("  Pass:     =  %s\n",global_opts.pg_pass);
  DEBUGOUT2("  Datenbank =  %s\n",global_opts.pg_database);

  if(walk_image_cfg_list())
    wait_for_childs();

  return EXIT_SUCCESS;
}


/* Diese Funktion beendet das Programm mit einer Fehlermeldung. */
void exit_error(char* err){
  DEBUGOUT1("\nEtwas unschoenes ist passiert\n");
  if(errno != 0){
    perror("Fehler");  
  }
  write(STDOUT_FILENO, err, strlen(err));
  exit(1);
}

/* Wird bei Beendigungssignalen ausgefuehrt */
static void exit_sig_handler(int signr){
  #ifdef DEBUG
  DEBUGOUT1("\n");
  switch (signr){
    case SIGABRT:
      DEBUGOUT1("SIGABRT Interupt erhalten!\n");
    case SIGTERM:
      DEBUGOUT1("SIGTERM Interupt erhalten!\n");
    case SIGQUIT:
      DEBUGOUT1("SIGQUIT Interupt erhalten!\n");
    case SIGINT:
      DEBUGOUT1("SIGINT Interupt erhalten!\n");
  }
  #endif
  DEBUGOUT1("Beende Programm...\n");
  exit(0);
}