/* Copyright (c) 2021, la-ninpre
 * 
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * *************************************************************************
 * 
 * this file contains main code for nimisewi.
 * 
 * nimisewi is a small program that generates random toki pona noun phrase.
 * toki pona is a small constructed language created by sonja lang 
 * (see https://tokipona.org).
 *
 * functions and variables here a primarily named in tokipona, just because i
 * can. but just in case there are annotations in english.
 *
 * sona nanpa li ike. taso ona li pali e nimi pona.
 */

#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include <sys/types.h>
#include <sys/time.h>

#include "nimisewi.h"
#include "nimitoki.h" /* nimi_toki, suli_pi_nimi_toki */

void
open_e_nanpa_sewi()
{
    /* initialize pseudorandom generator using pid, microseconds and seconds
     *
     * for such silly program there's no need to implement cryptographically
     * secure random number generator.
     */

    pid_t pid;
    struct timeval time;

    gettimeofday(&time, NULL);
    pid = getpid();
    srand(pid * time.tv_usec * time.tv_sec);
}

const char
*pana_e_nimi(const char *nimi_mute[],
             const int suli_pi_nimi_mute,
             const int nanpa_nimi)
{
    /* wrapper function to get word from array
     *
     * noun phrases in toki pona could have arbitrary amount of words and they
     * are left grouped (the leftmost word is main, and words to the right
     * are modifying it:
     *
     * ((nimi) sewi)
     *
     * special word 'pi' could be used to alter this grouping order to achieve
     * something like english preposition 'of'
     *
     * ((suli) pi ((nimi) mute))
     *
     * this functions inserts 'pi' in the middle to avoid generating
     * very heavy phrases.
     */

    if (nanpa_nimi > suli_pi_nimi_mute) {
        err(EXIT_FAILURE, "index out of bounds");
    } else if (nanpa_nimi == -1) {
        return "pi";
    } else {
        return nimi_mute[nanpa_nimi];
    }
}

void
pana_e_nanpa_nimi(struct nanpa_nimi *nn)
{
    /* generate random number, which is later used as number of words
     * in the phrase
     *
     * also here is made decision, whether to insert 'pi'
     */
    nn->pi_li_lon = 0;
    nn->nanpa_pi = -1;
    nn->nanpa_nimi = (rand() % 6);

    if (nn->nanpa_nimi == 2) {
        nn->pi_li_lon = rand() % 2;
    } else if (nn->nanpa_nimi > 2) {
        nn->pi_li_lon = 1;
    }
    if (nn->pi_li_lon) {
        nn->nanpa_nimi++;
        nn->nanpa_pi = (nn->nanpa_nimi / 2);
    }
}

void
pana_e_nanpa_pi_nimi_sewi(int *nanpa_sewi_mute,
                          const int suli_nimi,
                          struct nanpa_nimi *nn)
{
    /* create specified amount of random numbers
     *
     * they are used later as indices to get words from wordlist
     */

    int i;

    for (i = 0; i <= nn->nanpa_nimi; i++) {
        nanpa_sewi_mute[i] = rand() % suli_nimi;
    }

    if (nn->pi_li_lon) {
        nanpa_sewi_mute[nn->nanpa_pi] = -1;
    }
}

int
main(void)
{
    int *nanpa_sewi_nimi; /* container for random indices */
    int i;
    struct nanpa_nimi nn; /* see nimisewi.h */

#ifdef __OpenBSD__
    if (pledge("stdio", NULL) == -1) {
        err(EXIT_FAILURE, "pledge");
    }
#endif
    open_e_nanpa_sewi();

    pana_e_nanpa_nimi(&nn);

    nanpa_sewi_nimi = (int *) calloc(nn.nanpa_nimi + 1, sizeof(int));
    if (nanpa_sewi_nimi == NULL) {
        err(EXIT_FAILURE, "calloc");
    }

    pana_e_nanpa_pi_nimi_sewi(nanpa_sewi_nimi, suli_pi_nimi_toki, &nn);

    /* i think that this section could be improved. i had an idea that
     * it would be cool to include options to output in cgi format instead
     * of just text
     */
    for (i = 0; i < nn.nanpa_nimi; i++) {
        printf("%s ",
                pana_e_nimi(nimi_toki, suli_pi_nimi_toki, nanpa_sewi_nimi[i]));
    }
    printf("%s", pana_e_nimi(nimi_toki, suli_pi_nimi_toki, nanpa_sewi_nimi[i]));
    printf("\n");

    free(nanpa_sewi_nimi);

    return 0;
}