/*      $OpenBSD: column.c,v 1.27 2022/12/26 19:16:00 jmc Exp $ */
/*      $NetBSD: column.c,v 1.4 1995/09/02 05:53:03 jtc Exp $   */

/*
 * Copyright (c) 1989, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

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

#include <ctype.h>
#include <err.h>
#include <limits.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <wchar.h>
#include <wctype.h>

void  c_columnate(void);
void *ereallocarray(void *, size_t, size_t);
void  input(FILE *);
void  maketbl(void);
void  print(void);
void  r_columnate(void);
__dead void usage(void);

struct field {
        char *content;
        int width;
};

int termwidth;                  /* default terminal width */
int entries;                    /* number of records */
int eval;                       /* exit value */
int *maxwidths;                 /* longest record per column */
struct field **table;           /* one array of pointers per line */
wchar_t *separator = L"\t ";    /* field separator for table option */

int
main(int argc, char *argv[])
{
        struct winsize win;
        FILE *fp;
        int ch, tflag, xflag;
        char *p;
        const char *errstr;

        setlocale(LC_CTYPE, "");

        termwidth = 0;
        if ((p = getenv("COLUMNS")) != NULL)
                termwidth = strtonum(p, 1, INT_MAX, NULL);
        if (termwidth == 0 && ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) == 0 &&
            win.ws_col > 0)
                termwidth = win.ws_col;
        if (termwidth == 0)
                termwidth = 80;

        if (pledge("stdio rpath", NULL) == -1)
                err(1, "pledge");

        tflag = xflag = 0;
        while ((ch = getopt(argc, argv, "c:s:tx")) != -1) {
                switch(ch) {
                case 'c':
                        termwidth = strtonum(optarg, 1, INT_MAX, &errstr);
                        if (errstr != NULL)
                                errx(1, "%s: %s", errstr, optarg);
                        break;
                case 's':
                        if ((separator = reallocarray(NULL, strlen(optarg) + 1,
                            sizeof(*separator))) == NULL)
                                err(1, NULL);
                        if (mbstowcs(separator, optarg, strlen(optarg) + 1) ==
                            (size_t) -1)
                                err(1, "sep");
                        break;
                case 't':
                        tflag = 1;
                        break;
                case 'x':
                        xflag = 1;
                        break;
                default:
                        usage();
                }
        }

        if (!tflag)
                separator = L"";
        argv += optind;

        if (*argv == NULL) {
                input(stdin);
        } else {
                for (; *argv; ++argv) {
                        if ((fp = fopen(*argv, "r"))) {
                                input(fp);
                                (void)fclose(fp);
                        } else {
                                warn("%s", *argv);
                                eval = 1;
                        }
                }
        }

        if (pledge("stdio", NULL) == -1)
                err(1, "pledge");

        if (!entries)
                return eval;

        if (tflag)
                maketbl();
        else if (*maxwidths >= termwidth)
                print();
        else if (xflag)
                c_columnate();
        else
                r_columnate();
        return eval;
}

#define INCR_NEXTTAB(x) (x = (x + 8) & ~7)
void
c_columnate(void)
{
        int col, numcols;
        struct field **row;

        INCR_NEXTTAB(*maxwidths);
        if ((numcols = termwidth / *maxwidths) == 0)
                numcols = 1;
        for (col = 0, row = table;; ++row) {
                fputs((*row)->content, stdout);
                if (!--entries)
                        break;
                if (++col == numcols) {
                        col = 0;
                        putchar('\n');
                } else {
                        while (INCR_NEXTTAB((*row)->width) <= *maxwidths)
                                putchar('\t');
                }
        }
        putchar('\n');
}

void
r_columnate(void)
{
        int base, col, numcols, numrows, row;

        INCR_NEXTTAB(*maxwidths);
        if ((numcols = termwidth / *maxwidths) == 0)
                numcols = 1;
        numrows = entries / numcols;
        if (entries % numcols)
                ++numrows;

        for (base = row = 0; row < numrows; base = ++row) {
                for (col = 0; col < numcols; ++col, base += numrows) {
                        fputs(table[base]->content, stdout);
                        if (base + numrows >= entries)
                                break;
                        while (INCR_NEXTTAB(table[base]->width) <= *maxwidths)
                                putchar('\t');
                }
                putchar('\n');
        }
}

void
print(void)
{
        int row;

        for (row = 0; row < entries; row++)
                puts(table[row]->content);
}


void
maketbl(void)
{
        struct field **row;
        int col;

        for (row = table; entries--; ++row) {
                for (col = 0; (*row)[col + 1].content != NULL; ++col)
                        printf("%s%*s  ", (*row)[col].content,
                            maxwidths[col] - (*row)[col].width, "");
                puts((*row)[col].content);
        }
}

#define DEFNUM          1000
#define DEFCOLS         25

void
input(FILE *fp)
{
        static int maxentry = 0;
        static int maxcols = 0;
        static struct field *cols = NULL;
        int col, width, twidth;
        size_t blen;
        ssize_t llen;
        char *p, *s, *buf = NULL;
        wchar_t wc;
        int wlen;

        while ((llen = getline(&buf, &blen, fp)) > -1) {
                if (buf[llen - 1] == '\n')
                        buf[llen - 1] = '\0';

                p = buf;
                for (col = 0;; col++) {

                        /* Skip lines containing nothing but whitespace. */

                        for (s = p; (wlen = mbtowc(&wc, s, MB_CUR_MAX)) > 0;
                             s += wlen)
                                if (!iswspace(wc))
                                        break;
                        if (*s == '\0')
                                break;

                        /* Skip leading, multiple, and trailing separators. */

                        while ((wlen = mbtowc(&wc, p, MB_CUR_MAX)) > 0 &&
                            wcschr(separator, wc) != NULL)
                                p += wlen;
                        if (*p == '\0')
                                break;

                        /*
                         * Found a non-empty field.
                         * Remember the start and measure the width.
                         */

                        s = p;
                        width = 0;
                        while (*p != '\0') {
                                if ((wlen = mbtowc(&wc, p, MB_CUR_MAX)) == -1) {
                                        width++;
                                        p++;
                                        continue;
                                }
                                if (wcschr(separator, wc) != NULL)
                                        break;
                                if (*p == '\t')
                                        INCR_NEXTTAB(width);
                                else  {
                                        width += (twidth = wcwidth(wc)) == -1 ?
                                            1 : twidth;
                                }
                                p += wlen;
                        }

                        if (col + 1 >= maxcols) {
                                if (maxcols > INT_MAX - DEFCOLS)
                                        err(1, "too many columns");
                                maxcols += DEFCOLS;
                                cols = ereallocarray(cols, maxcols,
                                    sizeof(*cols));
                                maxwidths = ereallocarray(maxwidths, maxcols,
                                    sizeof(*maxwidths));
                                memset(maxwidths + col, 0,
                                    DEFCOLS * sizeof(*maxwidths));
                        }

                        /*
                         * Remember the width of the field,
                         * NUL-terminate and remember the content,
                         * and advance beyond the separator, if any.
                         */

                        cols[col].width = width;
                        if (maxwidths[col] < width)
                                maxwidths[col] = width;
                        if (*p != '\0') {
                                *p = '\0';
                                p += wlen;
                        }
                        if ((cols[col].content = strdup(s)) == NULL)
                                err(1, NULL);
                }
                if (col == 0)
                        continue;

                /* Found a non-empty line; remember it. */

                if (entries == maxentry) {
                        if (maxentry > INT_MAX - DEFNUM)
                                errx(1, "too many input lines");
                        maxentry += DEFNUM;
                        table = ereallocarray(table, maxentry, sizeof(*table));
                }
                table[entries] = ereallocarray(NULL, col + 1,
                    sizeof(*(table[entries])));
                table[entries][col].content = NULL;
                while (col--)
                        table[entries][col] = cols[col];
                entries++;
        }
}

void *
ereallocarray(void *ptr, size_t nmemb, size_t size)
{
        if ((ptr = reallocarray(ptr, nmemb, size)) == NULL)
                err(1, NULL);
        return ptr;
}

__dead void
usage(void)
{
        (void)fprintf(stderr,
            "usage: column [-tx] [-c columns] [-s sep] [file ...]\n");
        exit(1);
}