/* sea.c - fast sea prompt */
// c99
// cc -std=c99 -W -Wall -pedantic sea.c -o sea

#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define ANSI(n) "\\[\033[" n "m\\]"

#define PUNC    ANSI("36")
#define CLEAR   "\\[\033[m\017\\]"
#define TEXT    CLEAR
#define BOLD    ANSI("1")

#define put(s)  fputs((s), stdout)

int main(int argc, char **argv)
{
    // we assume argv[0] has no shell-special chars
    if (argc < 2) {
        put("argc() { echo ${#@}; }; export -f argc;\n"
            "export PROMPT_COMMAND='PS1=$('");
	printf("$(type -p %s)", argv[0]);
        put("' $? ers $? $(argc $(jobs -pr)) $(argc $(jobs -ps)))';\n");
        return 0;
    }

    argv++;
    int e = atoi(*argv++);      /* two arguments guaranteed; must
                                 * check hereafter */
    put(CLEAR PUNC "[");

    char *p = *argv ? *argv++ : 0;
    bool first = 1;
    while (p && *p && *argv) {
        int n;
        if ((n = atoi(*argv))) {
            printf("%s%c%i",
                   first ? first=0, TEXT : " ",
                   *p, n);
        }
        ++argv, ++p;
    }
    if (!first) put(PUNC "][");

    char *wd = getenv("PWD");
    if (!wd) wd = "";
    
    char *home = getenv("HOME");
    if (home) {
        size_t len = strlen(home);

        if (!strncmp(wd, home, len) && (wd[len] == '/' ||
                                        wd[len] == '\0')) {
            wd += len;
            *--wd = '~';
        }
    }

    size_t max = 20;
    size_t len = strlen(wd);
    if (len > max) {
        wd += len - max;
        strncpy(wd, "... ", 4);
    }
    
    printf(TEXT "\\u" PUNC "@" TEXT "\\h" PUNC ":" TEXT "%s"
           PUNC "]" CLEAR "\\$ ",
           wd);

    return e;
}