/**

 *  $Id: irc.c 51 2008-01-10 00:19:39Z mbroeker $

 * $URL: http://localhost/svn/c/mcbot/trunk/src/irc.c $

 *

 */

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <string.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <netinet/in.h>

#include <arpa/inet.h>

#include <netdb.h>

#include <pwd.h>

#include <irc.h>

#define VERSION_STRING "MCBOT on GNU/LINUX"

const char *IRC_Commands[] = {

    "NOTICE", "MODE", "JOIN", "PART",

    "TOPIC", "PING", "ENOMEM", "ERROR",

    "VERSION", "PRIVMSG", "QUIT", "NICK",

    NULL,

};

FILE *irc_connect (char *server, unsigned int port)

{

    struct hostent *he;

    char *ip;

    struct sockaddr_in ca;

    int csocket;

    FILE *stream;

    he = gethostbyname (server);

    if (he == NULL) {

        perror ("GETHOSTBYNAME");

        return NULL;

    }

    if ((ip = inet_ntoa (*((struct in_addr *)he->h_addr_list[0]))) == NULL) {

        perror ("GETHOSTBYNAME");

        return NULL;

    } else

        printf ("IP: %s\n", ip);

    ca.sin_family = AF_INET;

    ca.sin_addr.s_addr = inet_addr (ip);

    ca.sin_port = htons (port);

    csocket = socket (AF_INET, SOCK_STREAM, IPPROTO_TCP);

    if (connect (csocket, (struct sockaddr *)&ca, (socklen_t) sizeof (ca)) == -1) {

        perror ("CONNECT");

        return NULL;

    }

    /*

     * rw mode,but many seek errors ...

     */

    stream = fdopen (csocket, "a+");

    return stream;

}

int irc_login (FILE * stream, char *nick, char *password)

{

    MSG message;

    char msg[513];

    char *user;

    struct passwd *pwd = NULL;

    if ((user = getenv ("USER")) != NULL)

        if ((pwd = getpwnam (user)) == NULL)

            return IRC_GENERAL_ERROR;

    if (strlen (password) == 0)

        return IRC_LOGIN_ERROR;

    if (stream == NULL)

        return IRC_GENERAL_ERROR;

    fprintf (stream, "NICK %s\r\n", nick);

    fprintf (stream, "USER %s 0 irc.freenode.net %s\r\n", user, pwd->pw_gecos);

    fprintf (stream, "PRIVMSG NICKSERV :IDENTIFY %s\r\n", password);

    for (;;) {

        fgets (msg, 512, stream);

        if ((user = irc_parsemessage (msg, &message)) != NULL)

            printf ("%10s %s\n", user, message.line);

        if (strstr (msg, "VERSION") != NULL) {

            printf ("%10s %s", "VERSION", msg);

            printf ("%10s %s %s :%s\n", "WRITE", message.command, message.user, VERSION_STRING);

            fprintf (stream, "VERSION :%s\r\n", VERSION_STRING);

        }

        if (strstr (msg, ":Password accepted") != NULL) {

            break;

        }

        if (strstr (msg, ":You are now logged in.") != NULL) {

            break;

        }

        if (strstr (msg, ":Password Incorrect") != NULL) {

            return IRC_LOGIN_ERROR;

        }

        if (strstr (msg, "ERROR :Closing Link") != NULL) {

            return IRC_GENERAL_ERROR;

        }

        if (strstr (msg, "is not registered") != NULL) {

            return IRC_LOGIN_ERROR;

        }

    }

    sleep (2);

    return 0;

}

static char *irc_getmessage (const char *line, MSG * message)

{

    char *theLine;

    char *token;

    char *ptr;

    if ((theLine = strdup (line)) == NULL)

        return "ENOMEM";

    message->user = message->email = NULL;

    message->command = NULL;

    message->channel = message->line = NULL;

    token = strtok (theLine, " ");

    if (*token != ':') {

        /*

         * SERVER MESSAGES

         */

        if ((ptr = strtok (NULL, "\r\n")) != NULL)

            ++ptr;

        message->line = ptr;

        return token;

    }

    message->user = ++token;

    message->command = strtok (NULL, " ");

    message->line = strtok (NULL, "\r\n");

    return message->command;

}

/*

 * Main prints ("%10s %s %s\n", MSG->command MSG->channel MSG->line).

 * This functions makes sure, that there will be someting to print...

 */

char *irc_parsemessage (const char *line, MSG * message)

{

    int i;

    char *command;

    char *ptr;

    int value;

    i = 0;

    if ((command = irc_getmessage (line, message)) != NULL) {

        while (IRC_Commands[i] != NULL) {

            if (strcmp (IRC_Commands[i], command) == 0) {

                switch (i) {

                case 0:        /* NOTICE */

                    if (message->line == NULL) {

                        message->channel = "*";

                        message->line = "*";

                    } else {

                        message->channel = strtok (message->line, " ");

                        if ((message->line = strtok (NULL, "\r\n")) != NULL)

                            ++message->line;

                    }

                    return command;

                case 1:        /* MODE */

                    message->channel = strtok (message->line, " ");

                    message->line = strtok (NULL, "\r\n");

                    return command;

                case 2:        /* JOIN */

                case 3:        /* PART */

                    if ((message->channel = strchr (message->line, ':')))

                        ++message->channel;

                    message->line = message->user;

                    return command;

                case 4:        /* TOPIC */

                    message->channel = strtok (message->line, " ");

                    if ((message->line = strtok (NULL, "\r\n")))

                        ++message->line;

                    return command;

                case 5:        /* PING */

#ifdef DEBUG

                    printf ("%10s %s localhost\n", "PING", message->line);

#endif

                    fprintf (message->stream, "PONG :%s\r\n", message->line);

                    message->channel = "localhost";

#ifdef DEBUG

                    return "PONG";

#else

                    return NULL;

#endif

                case 6:        /* ENOMEM */

                case 7:        /* ERROR */

                    exit (-1);

                    break;

                case 8:        /* VERSION */

                    if ((ptr = strchr (message->user, ' ')))

                        *ptr = 0;

                    return command;

                case 9:        /* PRIVMSG */

                    if ((message->email = strchr (message->user, '=')))

                        ++message->email;

                    if ((ptr = strchr (message->user, '!')))

                        *ptr = 0;

                    message->channel = strtok (message->line, " ");

                    message->line = strtok (NULL, "\r\n");

                    message->line++;

                    printf ("%10s %s %s :%s\n", "READ", message->command, message->channel, message->line);

                    return NULL;

                case 10:       /* QUIT */

                    message->channel = message->user;

                    return command;

                case 11:       /* NICK */

                    message->channel = message->user;

                    return command;

                }

            }

            i++;

        }

        if ((value = atoi (command)) != 0) {

            switch (value) {

            case 1:            /* CONNECTION INFOS */

            case 2:

            case 3:

            case 4:

            case 5:

            case 250:

            case 251:

            case 252:

            case 254:

            case 255:

            case 265:

            case 266:

                /*

                 * prints as is in irc_login

                 */

                return command;

                break;

            case 311:

            case 312:

            case 315:          /* END OF WHO */

            case 318:

                message->channel = strtok (message->line, " ");

                message->line = strtok (NULL, "\r\n");

                return command;

            case 319:

                message->channel = strtok (message->line, " ");

                message->line = strtok (NULL, "\r\n");

                fprintf (message->stream, "PRIVMSG %s :%s\r\n", "#mcbot", message->line);

                return command;

            case 320:

            case 332:          /* TOPIC OF CHANNEL */

            case 333:          /* NAMES IN CHANNEL */

                message->channel = strtok (message->line, " ");

                message->line = strtok (NULL, "\r\n");

                return command;

            case 351:          /* SVERSION */

                message->channel = strtok (message->line, " ");

                message->line = strtok (NULL, "\r\n");

                return command;

            case 352:          /* WHO LIST */

                message->channel = strtok (message->line, " ");

                message->line = strtok (NULL, "\r\n");

                /*

                 * MORE THAN 3 LINES AND YOU WILL be KICKED

                 */

                return command;

                break;

            case 353:

            case 365:

            case 366:          /* END OF NAMES */

                message->channel = strtok (message->line, " ");

                message->line = strtok (NULL, "\r\n");

                return command;

                break;

            case 372:          /* MOTD MESSAGES */

            case 375:

            case 376:          /* END OF MOTD */

                return command;

                break;

            case 401:          /* NO SUCH NICK/CHANNEL */

            case 403:          /* That CHANNEL doesnt exist */

                return command;

                break;

            case 474:

            case 475:

            case 476:

            case 477:

                message->channel = strtok (message->line, " ");

                message->line = strtok (NULL, "\r\n");

                return command;

                break;

            case 901:          /* notify or some crap */

                message->channel = strtok (message->line, " ");

                message->line = strtok (NULL, "\r\n");

                return command;

                break;

            default:

                printf ("DEBUG   %s", line);

                printf ("Unknown Value: %d\n", value);

            }

        }

        printf ("DEBUG   %s", line);

        printf ("Unknown Command: %s\n", command);

        return command;

    }

    printf ("DEBUG   %s", line);

    return NULL;

}