/*

    Task Spooler - a task queue system for the unix user

    Copyright (C) 2007  Lluís Batlle i Rossell

    Please find the license in the provided COPYING file.

*/

#include <unistd.h>

#include <stdlib.h>

#include <string.h>

#include <signal.h>

#include <stdio.h>

#include "main.h"

extern char *optarg;

extern int optind, opterr, optopt;

/* Globals */

struct Command_line command_line;

int server_socket;

/* Globals for the environment of getopt */

static char getopt_env[] = "POSIXLY_CORRECT=YES";

static char *old_getopt_env;

static char version[] = "Task Spooler v0.4.1 - a task queue system for the unix user.\n"

"Copyright (C) 2007  Lluis Batlle i Rossell";

static void default_command_line()

{

    command_line.request = c_LIST;

    command_line.need_server = 0;

    command_line.store_output = 1;

    command_line.should_go_background = 1;

    command_line.should_keep_finished = 1;

    command_line.gzip = 0;

    command_line.send_output_by_mail = 0;

}

void get_command(int index, int argc, char **argv)

{

    command_line.command.array = &(argv[index]);

    command_line.command.num = argc - index;

}

static int get_two_jobs(const char *str, int *j1, int *j2)

{

    char tmp[50];

    char *tmp2;

    if(strlen(str) >= 50)

        return 0;

    strcpy(tmp, str);

    tmp2 = strchr(tmp , '-');

    if (tmp2 == NULL)

        return 0;

    /* We change the '-' to '\0', so we have a delimiter,

     * and we can access the two strings for the ids */

    *tmp2 = '\0';

    /* Skip the '\0', and point tmp2 to the second id */

    ++tmp2;

    *j1 = atoi(tmp);

    *j2 = atoi(tmp2);

    return 1;

}

void parse_opts(int argc, char **argv)

{

    int c;

    int res;

    /* Parse options */

    while(1) {

        c = getopt(argc, argv, ":VhKgClnfmr:t:c:o:p:w:u:s:U:");

        if (c == -1)

            break;

        switch(c)

        {

            case 'K':

                command_line.request = c_KILL_SERVER;

                command_line.should_go_background = 0;

                break;

            case 'l':

                command_line.request = c_LIST;

                break;

            case 'h':

                command_line.request = c_SHOW_HELP;

                break;

            case 'V':

                command_line.request = c_SHOW_VERSION;

                break;

            case 'C':

                command_line.request = c_CLEAR_FINISHED;

                break;

            case 'c':

                command_line.request = c_CAT;

                command_line.jobid = atoi(optarg);

                break;

            case 'o':

                command_line.request = c_SHOW_OUTPUT_FILE;

                command_line.jobid = atoi(optarg);

                break;

            case 'n':

                command_line.store_output = 0;

                break;

            case 'g':

                command_line.gzip = 1;

                break;

            case 'f':

                command_line.should_go_background = 0;

                break;

            case 'm':

                command_line.send_output_by_mail = 1;

                break;

            case 't':

                command_line.request = c_TAIL;

                command_line.jobid = atoi(optarg);

                break;

            case 'p':

                command_line.request = c_SHOW_PID;

                command_line.jobid = atoi(optarg);

                break;

            case 'r':

                command_line.request = c_REMOVEJOB;

                command_line.jobid = atoi(optarg);

                break;

            case 'w':

                command_line.request = c_WAITJOB;

                command_line.jobid = atoi(optarg);

                break;

            case 'u':

                command_line.request = c_URGENT;

                command_line.jobid = atoi(optarg);

                break;

            case 's':

                command_line.request = c_GET_STATE;

                command_line.jobid = atoi(optarg);

                break;

            case 'U':

                command_line.request = c_SWAP_JOBS;

                res = get_two_jobs(optarg, &command_line.jobid,

                        &command_line.jobid2);

                if (!res)

                {

                    fprintf(stderr, "Wrong <id-id> for -U.\n");

                    exit(-1);

                }

                if (command_line.jobid == command_line.jobid2)

                {

                    fprintf(stderr, "Wrong <id-id> for -U. "

                            "Use different ids.\n");

                    exit(-1);

                }

                break;

            case ':':

                switch(optopt)

                {

                    case 't':

                        command_line.request = c_TAIL;

                        command_line.jobid = -1; /* This means the 'last' job */

                        break;

                    case 'c':

                        command_line.request = c_CAT;

                        command_line.jobid = -1; /* This means the 'last' job */

                        break;

                    case 'o':

                        command_line.request = c_SHOW_OUTPUT_FILE;

                        command_line.jobid = -1; /* This means the 'last' job */

                        break;

                    case 'p':

                        command_line.request = c_SHOW_PID;

                        command_line.jobid = -1; /* This means the 'last' job */

                        break;

                    case 'r':

                        command_line.request = c_REMOVEJOB;

                        command_line.jobid = -1; /* This means the 'last'

                                                    added job */

                        break;

                    case 'w':

                        command_line.request = c_WAITJOB;

                        command_line.jobid = -1; /* This means the 'last'

                                                    added job */

                        break;

                    case 'u':

                        command_line.request = c_URGENT;

                        command_line.jobid = -1; /* This means the 'last'

                                                    added job */

                        break;

                    case 's':

                        command_line.request = c_GET_STATE;

                        command_line.jobid = -1; /* This means the 'last'

                                                    added job */

                        break;

                    default:

                        fprintf(stderr, "Option %c missing argument: %s\n",

                                optopt, optarg);

                        exit(-1);

                }

                break;

            case '?':

                fprintf(stderr, "Wrong option %c.\n", optopt);

                exit(-1);

        }

    }

    command_line.command.num = 0;

    /* if the request is still the default option... 

     * (the default values should be centralized) */

    if (optind < argc && command_line.request == c_LIST)

    {

        command_line.request = c_QUEUE;

        get_command(optind, argc, argv);

    }

    if (command_line.request != c_SHOW_HELP &&

            command_line.request != c_SHOW_VERSION)

        command_line.need_server = 1;

    if ( ! command_line.store_output && ! command_line.should_go_background )

        command_line.should_keep_finished = 0;

    if ( command_line.send_output_by_mail && ((! command_line.store_output) ||

                command_line.gzip) )

    {

        fprintf(stderr,

                "For e-mail, you should store the output (not through gzip)\n");

        exit(-1);

    }

}

static void fill_first_3_handles()

{

    int tmp_pipe1[2];

    int tmp_pipe2[2];

    /* This will fill handles 0 and 1 */

    pipe(tmp_pipe1);

    /* This will fill handles 2 and 3 */

    pipe(tmp_pipe2);

    close(tmp_pipe2[1]);

}

static void go_background()

{

    int pid;

    pid = fork();

    switch(pid)

    {

        case -1:

            error("fork failed");

            break;

        case 0:

            close(0);

            close(1);

            close(2);

            /* This is a weird thing. But we will later want to

             * allocate special files to the 0, 1 or 2 fds. It's

             * almost impossible, if other important things got

             * allocated here. */

            fill_first_3_handles();

            setsid();

            break;

        default:

            exit(0);

    }

}

static void print_help(const char *cmd)

{

    printf("usage: %s [action] [-ngfm] [cmd...]\n", cmd);

    printf("Env vars:\n");

    printf("  TS_SOCKET  the path to the unix socket used by the ts command\n");

    printf("  TS_MAILTO  where to mail the result (on -m). Local user by default\n");

    printf("  TS_MAXFINISHED  maximum finished jobs in the queue\n");

    printf("  TS_ONFINISH  binary called on job end (passing jobid, error, outfile, command)\n");

    printf("Actions:\n");

    printf("  -K       kill the task spooler server\n");

    printf("  -C       clear the list of finished jobs\n");

    printf("  -l       show the job list (default action)\n");

    printf("  -t [id]  tail -f the output of the job. Last run if not specified.\n");

    printf("  -c [id]  cat the output of the job. Last run if not specified.\n");

    printf("  -p [id]  show the pid of the job. Last run if not specified.\n");

    printf("  -o [id]  show the output file. Of last job run, if not specified.\n");

    printf("  -s [id]  show the job state. Of the last added, if not specified.\n");

    printf("  -r [id]  remove a job. The last added, if not specified.\n");

    printf("  -w [id]  wait for a job. The last added, if not specified.\n");

    printf("  -u [id]  put that job first. The last added, if not specified.\n");

    printf("  -U <id-id>  swap two jobs in the queue.\n");

    printf("  -h       show this help\n");

    printf("  -V       show the program version\n");

    printf("Options adding jobs:\n");

    printf("  -n       don't store the output of the command.\n");

    printf("  -g       gzip the stored output (if not -n).\n");

    printf("  -f       don't fork into background.\n");

    printf("  -m       send the output by e-mail (uses sendmail).\n");

}

static void print_version()

{

    puts(version);

}

static void set_getopt_env()

{

    old_getopt_env = getenv("POSIXLY_CORRECT");

    putenv(getopt_env);

}

static void unset_getopt_env()

{

    if (old_getopt_env == NULL)

    {

        /* Wipe the string from the environment */

        putenv("POSIXLY_CORRECT");

    }

    else

        sprintf(getopt_env, "POSIXLY_CORRECT=%s", old_getopt_env);

}

int main(int argc, char **argv)

{

    int errorlevel = 0;

    process_type = CLIENT;

    set_getopt_env();

    /* This is needed in a gnu system, so getopt works well */

    default_command_line();

    parse_opts(argc, argv);

    unset_getopt_env();

    /* This will be inherited by the server, if it's run */

    ignore_sigpipe();

    if (command_line.need_server)

        ensure_server_up();

    switch(command_line.request)

    {

    case c_SHOW_VERSION:

        print_version(argv[0]);

        break;

    case c_SHOW_HELP:

        print_help(argv[0]);

        break;

    case c_QUEUE:

        if (command_line.command.num <= 0)

            error("Tried to queue a void command. parameters: %i",

                    command_line.command.num);

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        c_new_job();

        command_line.jobid = c_wait_newjob_ok();

        if (command_line.store_output)

        {

            printf("%i\n", command_line.jobid);

            fflush(stdout);

        }

        if (command_line.should_go_background)

        {

            go_background();

            c_wait_server_commands();

        } else

        {

            errorlevel = c_wait_server_commands();

        }

        break;

    case c_LIST:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        c_list_jobs();

        c_wait_server_lines();

        break;

    case c_KILL_SERVER:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        c_shutdown_server();

        break;

    case c_CLEAR_FINISHED:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        c_clear_finished();

        break;

    case c_TAIL:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        c_tail();

        /* This will not return! */

        break;

    case c_CAT:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        c_cat();

        /* This will not return! */

        break;

    case c_SHOW_OUTPUT_FILE:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        c_show_output_file();

        break;

    case c_SHOW_PID:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        c_show_pid();

        break;

    case c_REMOVEJOB:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        c_remove_job();

        break;

    case c_WAITJOB:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        errorlevel = c_wait_job();

        break;

    case c_URGENT:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        c_move_urgent();

        break;

    case c_SWAP_JOBS:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        c_swap_jobs();

        break;

    case c_GET_STATE:

        if (!command_line.need_server)

            error("The command %i needs the server", command_line.request);

        /* This will also print the state into stdout */

        c_get_state();

        break;

    }

    if (command_line.need_server)

    {

        close(server_socket);

    }

    return errorlevel;

}