/*
 * guinnessd
 * architecture clients/serveur guinness
 * Thomas Nemeth -- le 15 juin 2001
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include <errno.h>
#include <signal.h>
#include <pthread.h>
#include <fcntl.h>
#include <getopt.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <strings.h>
#include <locale.h>
#include "defines.h"
#include "xmem.h"
#include "tools.h"
#include "printlog.h"
#include "lists.h"
#include "broadcast.h"
#include "drinks.h"
#include "clients.h"
#include "guinnessd.h"
#include "commands.h"
#include "config.h"

/* Config specifique  serveur */
char *adr_ip       = NULL;
int   port         = 0;
int   online       = TRUE;
char *fichierlog   = NULL;
char *fichiercfg   = NULL;
char *chemin       = NULL;
char *admin_passwd = NULL;
FILE *logfile      = NULL;
FILE *outerr       = NULL;
Elt  *clients_list = NULL;
Elt  *drinks_list  = NULL;

/* Config specifique connexion des clients */
char *pseudo       = NULL;
char *drink        = NULL;
char *logout       = NULL;


#ifdef SunOS
char *crypt(const char *key, const char *salt);
#else
extern char *crypt __P ((__const char *__key, __const char *__salt));
#endif


void install_handler ();


/*
 * Gestionnaire de signal SIGPIPE, SIGTERM, SIGQUIT et SIGINT
 *
 */
void handler_signaux (int sig) {
    switch (sig) {
        case SIGPIPE:
            printlog (LOG_NOTIFY, "Signal SIGPIPE recu...\n");
            install_handler ();
            break;
        case SIGTERM:
        case SIGQUIT:
        case SIGINT:
            online = FALSE;
            printlog (LOG_NOTIFY, "Signal de terminaison recu...\n");
            break;
        default:
            printlog (LOG_NOTIFY, "Signal recu...\n");
    }
}


/*
 * Lecture du fichier de config : recuperation des valeurs
 *
 */
char *get_string_from_token (char *line) {
    char *result = line;
    char *tmp;
    int   keyval = 0;

    while ( (keyval != 1) && (result [0] != 0) ) {
        if (result [0] == '=') keyval = 1;
        if (keyval == 0) result++;
    }
    tmp = result++;
    while (tmp [0] != 0) {
        if (tmp [0] == '\n') tmp [0] = 0;
        tmp++;
    }
    return result;
}


/*
 * Lecture du fichier de config
 *
 */
void load_config () {
    FILE *file;
    char  tmpstr[MAXSTRLEN + 1];
    char *value;

    /* Ouverture du fichier */
    if ( (file = fopen (fichiercfg?fichiercfg:CONFIG_FILE, "r") ) != NULL) {
        /* Lecture du fichier */
        while (! feof (file) ) {
            memset (tmpstr, 0, MAXSTRLEN + 1);
            fgets (tmpstr, (int) MAXSTRLEN, file);
            value = get_string_from_token (tmpstr);
            if ( (strncmp (tmpstr, "port=", 5) == 0) && (port == 0) )
                port = atoi (value);
            if ( (strncmp (tmpstr, "passwd=", 7) == 0) &&
                 (admin_passwd == NULL) )
                admin_passwd = xstrdup (crypt (value, "Gs") + 2);
            if ( (strncmp (tmpstr, "rep=", 4) == 0) && (chemin == NULL) )
                chemin = xstrdup (value);
            if ( (strncmp (tmpstr, "pseudo=", 7) == 0) && (pseudo == NULL) )
                pseudo = xstrdup (value);
            if ( (strncmp (tmpstr, "drink=", 6) == 0) && (drink == NULL) )
                drink = xstrdup (value);
            if ( (strncmp (tmpstr, "logout=", 7) == 0) && (logout == NULL) )
                logout = xstrdup (value);
        }
        fclose (file);
#ifdef DEBUG
    } else {
        fprintf (stderr, "Pas de fichier de config (%s).\n", CONFIG_FILE);
#endif
    }
}


/*
 * Aide
 *
 */
void Usage (int help) {
    printf ("guinnessd by Thomas Nemeth - v %s (compilation %s : %s)\n",
            VERSION, OS_TYPE, COMPIL_DATE);
    if (help)
        printf ("Usage : guinnessd [-h] [-v] [-b] [-p port] "
                "[-s passwd] [-d chemin] [-l fichier] [-f fichier]\n"
                "   -h         : aide sur les parametres\n"
                "   -v         : affiche la version\n"
                "   -b         : detache le serveur du terminal\n"
                "   -a adresse : specifie l'adresse du serveur\n"
                "   -p port    : specifie le numero du port\n"
                "   -s passwd  : specifie le mot de passe d'aministration\n"
                "   -d chemin  : indique le chemin ou se"
                " trouvent les ascii-arts\n"
                "   -l fichier : fichier de log\n"
                "   -f fichier : fichier de configuration\n\n");
    exit (1);
}


/*
 * Traitement des arguments
 *
 */
int traite_argv (int argc, char *argv[]) {
    int option;
    int detach = FALSE;

    /* Verification des parametres */
    while ((option = getopt (argc, argv, "hvba:p:s:d:l:f:")) != -1) {
        switch (option) {
            case 'h' :
                Usage (TRUE);
                break;
            case 'v' :
                Usage (FALSE);
                break;
            case 'b' :
                detach = TRUE;
                break;
            case 'a' :
                adr_ip = optarg;
                break;
            case 'p' :
                port = atoi (optarg);
                break;
            case 's' :
                admin_passwd = xstrdup (crypt (optarg, "Gs") + 2);
                break;
            case 'd' :
                if (! chemin) {
                    if (optarg[0] == '/') {
                        chemin = xstrdup (optarg);
                    } else {
                        char *Pwd;
                        Pwd = xmalloc ((MAXSTRLEN + 1) * sizeof (char));
                        getcwd (Pwd, MAXSTRLEN);
                        chemin = xmalloc ( (strlen (Pwd) + strlen (optarg) + 2)
                                           * sizeof (char) );
                        snprintf (chemin, MAXSTRLEN, "%s/%s",
                                  Pwd, optarg);
                    }
                }
                break;
            case 'l' :
                if (! fichierlog) {
                    fichierlog = xstrdup (optarg);
                }
                break;
            case 'f' :
                if (! fichiercfg) {
                    fichiercfg = xstrdup (optarg);
                }
                break;
            default:
                Usage (TRUE);
                break;
        }
    }
    if (optind < argc) {
        if (argc - optind == 1)
            fprintf (stderr, "%s: option inconnue --", argv[0]);
        else
            fprintf (stderr, "%s: options inconnues --", argv[0]);
        for ( ; optind < argc ; optind++)
            fprintf (stderr, " %s", argv[optind]);
        fprintf (stderr, "\n");
        Usage (TRUE);
    }

    return detach;
}


/*
 * Fonction initiant la connexion.
 *
 */
int initiate (int socket_service, userinfos *infos) {
    int        cont = TRUE;
    char       userdatas[MAXSTRLEN];
    char      *datas, *token, *saveptr;
    char       delim[] = "\n\r";
    char      *nom_distant = NULL;
    char      *ip_distant = NULL;
    int        port_distant = 0;
    int        port_local = 0;
    time_t     now;
    struct tm *today;

    memset (userdatas, 0, MAXSTRLEN);

    /* Recuperation des infos sur le connecte */
    get_sock_infos (socket_service,
                    &nom_distant, &ip_distant,
                    &port_local, &port_distant);
    if (ip_distant) {
        snprintf (infos->ip, MAXSTRLEN, "%s", ip_distant);
        free (ip_distant);
    } else sprintf (infos->ip, "0.0.0.0");
    if (nom_distant) {
        snprintf (infos->host, MAXSTRLEN, "%s", nom_distant);
        free (nom_distant);
    } else sprintf (infos->host, "none");
    infos->port = port_distant;

    printlog (LOG_NOTIFY, "Connexion entrante : %s %s\n",
              infos->ip, infos->host ? infos->host : "");
    printlog (LOG_NOTIFY, "Ports (loc/dist)   : %d / %d\n",
              port_local, infos->port);

    /* PROTOCOLE DE CONNEXION */
    /* 1. envoi des commandes du serveur */
    if ( (cont = send_servercmds (socket_service)) == FALSE)
        return cont;

    /* 2. attente des donnees du connecte */
    if ( (cont = read_infos (socket_service, userdatas)) == FALSE)
        return cont;

    /* FIN DU PROTOCOLE : Vericifations / ajout dans la liste / affichage */
    datas = xstrdup (userdatas);

    /* Nom d'utilisateur */
    token = strtok_r (datas, delim, &saveptr);
    snprintf (infos->nom, MAXSTRLEN, "%s", token ? token : pseudo);

    /* Boisson preferee */
    token = strtok_r (NULL, delim, &saveptr);
    snprintf (infos->prefb, MAXSTRLEN, "%s", token ? token : drink);

    /* Message d'au-revoir */
    token = strtok_r (NULL, delim, &saveptr);
    snprintf (infos->logout, MAXSTRLEN, "%s", token ? token : logout);

    /* Date de connexion */
    time (&now);
    today = localtime (&now);
    strftime (infos->cxdate, MAXSTRLEN, "%a %d %b %Y %T", today);

    printlog (LOG_NOTIFY, "Utilisateur        : [%s]\n", infos->nom);
    printlog (LOG_NOTIFY, "Boisson preferee   : [%s]\n", infos->prefb);
    printlog (LOG_NOTIFY, "Message de logout  : [%s]\n", infos->logout);
    printlog (LOG_NOTIFY, "Date de connexion  : [%s]\n", infos->cxdate);

    pthread_mutex_lock (&mutex_clients);
    if (exist_elt (clients_list, infos->nom)) {
        char nick_ok[MAXSTRLEN+1];
        snprintf (nick_ok, MAXSTRLEN, "@%s", infos->nom);
        snprintf (infos->nom, MAXSTRLEN, "%s", nick_ok);
        send_infos (socket_service, "@Pseudo deja utilise !\n");
        printlog (LOG_NOTIFY, "Pseudo deje utilise => %s\n", infos->nom);
        pthread_mutex_unlock (&mutex_clients);
        return FALSE;
    }
    send_infos (socket_service, "Bienvenue sur le serveur de Guinness.\n");
    add_client (infos);
    pthread_mutex_unlock (&mutex_clients);

    if (! exist_elt (drinks_list, infos->prefb))
        send_infos (socket_service,
                    "Votre boisson preferee n'est pas disponible sur ce"
                    " serveur !\nVous aurez des Guinness a la place.\n");

    /* Passage en mode non bloquant */
    fcntl (socket_service, F_SETFL, O_NONBLOCK);

    return cont;
}


/*
 * Fonction de traitement de la connexion avec les clients
 *
 */
void thread_service (int *sock_serv) {
    pthread_t tid            = pthread_self ();
    long      old_id         = get_broadcastid ();
    int       socket_service = (int) *sock_serv;
    int       cont           = TRUE;
    int       nb;
    userinfos infos;
    char      commande[MAXSTRLEN + 1];

    pthread_detach (tid);

    memset (infos.nom,    0, MAXSTRLEN + 1);
    memset (infos.prefb,  0, MAXSTRLEN + 1);
    memset (infos.logout, 0, MAXSTRLEN + 1);
    infos.admin = FALSE;
    infos.cold  = FALSE;

    cont = initiate (socket_service, &infos);

    if (cont) {
        snprintf (commande, MAXSTRLEN,
                  "%s a rejoint le serveur de Guinness.\n", infos.nom);
        broadcast (MESSAGE, NULL, commande);
    }

#ifdef DEBUG
    printlog (LOG_NOTIFY, "Pret a recevoir des commandes.\n");
#endif

    while (cont == TRUE) {
        memset (commande, 0, MAXSTRLEN + 1);

        /* Lecture des caracteres recus */
        do {
            sleep (1);
            nb = read (socket_service, commande, MAXSTRLEN);
            if ( (nb == -1) || (nb == 0) ) {
                if ( (errno == EAGAIN) && (nb == -1) ) continue;
                if ( (errno == EPIPE) || (nb == 0) ) {
                    cont = FALSE;
                } else {
                    printlog (LOG_ERROR, "Erreur de connexion reception !\n");
                }
            }
        } while ( (cont != FALSE) &&
                  (nb < 0) &&
                  (new_message (old_id) != TRUE) );

#ifdef DEBUG
        printlog (LOG_NOTIFY, "Commande recue.\n");
#endif
        if (cont == TRUE) {
            /* Traitement de la commande */
            if (nb > 0)
                cont = reply (socket_service, commande, &infos);
            /* Broadcast */
            if (new_message (old_id) == TRUE) {
                old_id = get_broadcastid ();
                cont = send_broadcast (socket_service, &infos);
#ifdef DEBUG
                printlog (LOG_ERROR, "Emission broadcast pour %s (id = %ld)\n",
                         infos.nom, old_id);
#endif
            }
        }
    }
    printlog (LOG_NOTIFY, "Bye bye %s...\n", infos.nom);

    if (infos.nom[0] != '@') {
        pthread_mutex_lock (&mutex_clients);
        remove_client (&infos);
        pthread_mutex_unlock (&mutex_clients);

        broadcast (QUITTER, infos.nom, infos.logout);
    }

    close (socket_service);
}


/*
 * Installation du gestionnaire de signal SIGPIPE et autres...
 *
 */
void install_handler () {
    signal (SIGPIPE, handler_signaux);
    signal (SIGTERM, handler_signaux);
    signal (SIGQUIT, handler_signaux);
    signal (SIGINT,  handler_signaux);
}


/*
 * Initialisation generale
 *
 */
void guinnessd_init (int argc, char *argv[]) {
    pthread_mutexattr_t mutex_attr;

    setlocale (LC_ALL, "");
    install_handler ();

    /* Valeurs par defaut */
    logfile = stdout;
    outerr  = stderr;

    /* Traitement des parametres */
    if (traite_argv (argc, argv) == TRUE) {
        switch (fork()) {
            case -1: /* erreur */
                perror ("fork()"); 
                exit (-1);
            case  0: /* le fils */
                setsid ();
                break;
            default: /* le pere */
                exit (0);
        }
    }

    /* Lecture du fichier de configuration */
    load_config ();

    /* Initialisation des semaphores */
    pthread_mutexattr_init (&mutex_attr);
    pthread_mutex_init (&mutex_broadcast, &mutex_attr);
    pthread_mutex_init (&mutex_clients, &mutex_attr);

    /* Affectation des parametres */
    if (IS_NOT_GOOD (pseudo))  SET_STRING (pseudo,  DEFAULT_PSEUDO);
    if (IS_NOT_GOOD (drink))   SET_STRING (drink,   DEFAULT_DRINK);
    if (IS_NOT_GOOD (logout))  SET_STRING (logout,  DEFAULT_LOGOUT);
    if (port == 0) port = DEFAULT_SERVER_PORT;
    if (fichierlog) {
        if ((logfile = fopen (fichierlog, "a"))) {
            outerr  = logfile;
        } else {
            fprintf (stderr, "Impossible d'ouvrir le fichier %s : %s\n",
                     fichierlog, strerror(errno));
        }
    }

    /* Option pour le buffer de logs */
    setvbuf (logfile, NULL, _IOLBF, 0);

    /* Creation de la liste de boissons par defaut*/
    add_elt (&drinks_list, "guinness");

    if (! chemin) chemin = xstrdup (DRINKS_DIR);
    drinks_list_files (chemin);
    drinks_display_list ();
}


/*
 * Fonction principale
 *
 */
int main (int argc, char *argv[]) {
    int                  socket_ecoute;
    int                  socket_service;
    socklen_t            lg_adresse = sizeof (struct sockaddr_in);
    struct sockaddr_in   adresse;
    pthread_t            pthread_id;

    guinnessd_init (argc, argv);

    /* Installation de l'ecoute du serveur */
    if ( (socket_ecoute = install_server (port, adr_ip, NULL)) == -1) {
        printlog (LOG_ERROR, "Impossible d'installer le service.\n");
        return -1;
    }

    /* Passage en mode non-bloquant */
    fcntl (socket_ecoute, F_SETFL, O_NONBLOCK);

    /* Boucle d'attente et d'ouverture de connexions */
    printlog (LOG_NOTIFY, "Serveur en attente de connexions (port %d)...\n",
              port);
    while (online == TRUE) {
        sleep (1);

        /* Attente d'une connexion */
        socket_service = accept (socket_ecoute, (struct sockaddr *) &adresse,
                                 &lg_adresse);

        /* SIGPIPE */
        if ( (socket_service == -1) && (errno == EINTR) ) continue;

        /* PAS DE CONNEXION => mode non bloquant pour attendre un ordre de
         * terminaison
         */
        if ( (socket_service == -1) && (errno == EAGAIN) ) continue;

        /* Autre erreur socket */
        if (socket_service == -1) {
            /* Erreur */
            printlog (LOG_ERROR,
                      "Erreur d'acceptation de socket, errno = %d.\n",
                      errno);
            perror (__FILE__ " accept");
            close (socket_ecoute);
            return -1;
        }

        /* Ici connexion acceptee */
        printlog (LOG_NOTIFY, "Connexion acceptee...\n");

        /* Lancement d'une activite de traitement */
        if (pthread_create (&pthread_id, NULL/*pthread_attr_default*/,
                            (void *) thread_service,
                            (void *) &socket_service) == -1) {
            printlog (LOG_ERROR, "Erreur creation thread de service.\n");
            close (socket_service);
        }
        /* fflush (logfile); */
        sleep (2);
    }

    printlog (LOG_NOTIFY, "Arret du serveur demande.\n");
    /* fflush (logfile); */
    close (socket_ecoute);

    free_list (&clients_list);
    free_list (&drinks_list);

    pthread_mutex_destroy (&mutex_broadcast);
    pthread_mutex_destroy (&mutex_clients);

    return 0;
}