/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1993
 *      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.
 */

/*
 *      rs - reshape a data array
 *      Author:  John Kunze, Office of Comp. Affairs, UCB
 *              BEWARE: lots of unfinished edges
 */

#include <err.h>
#include <ctype.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <vector>

static long     flags;
#define TRANSPOSE       000001
#define MTRANSPOSE      000002
#define ONEPERLINE      000004
#define ONEISEPONLY     000010
#define ONEOSEPONLY     000020
#define NOTRIMENDCOL    000040
#define SQUEEZE         000100
#define SHAPEONLY       000200
#define DETAILSHAPE     000400
#define RIGHTADJUST     001000
#define NULLPAD         002000
#define RECYCLE         004000
#define SKIPPRINT       010000
#define ICOLBOUNDS      020000
#define OCOLBOUNDS      040000
#define ONEPERCHAR      0100000
#define NOARGS          0200000

static short    *colwidths;
static std::vector<char *> elem;
static char     *curline;
static size_t   curlen;
static size_t   irows, icols;
static size_t   orows = 0, ocols = 0;
static size_t   maxlen;
static int      skip;
static int      propgutter;
static char     isep = ' ', osep = ' ';
static char     blank[] = "";
static size_t   owidth = 80, gutter = 2;

static void       getargs(int, char *[]);
static void       getfile(void);
static int        get_line(void);
static long       getnum(const char *);
static void       prepfile(void);
static void       prints(char *, int);
static void       putfile(void);
static void usage(void);

int
main(int argc, char *argv[])
{
        getargs(argc, argv);
        getfile();
        if (flags & SHAPEONLY) {
                printf("%zu %zu\n", irows, icols);
                exit(0);
        }
        prepfile();
        putfile();
        exit(0);
}

static void
getfile(void)
{
        char *p, *sp;
        char *endp;
        int c;
        int multisep = (flags & ONEISEPONLY ? 0 : 1);
        int nullpad = flags & NULLPAD;
        size_t len, padto;

        while (skip--) {
                c = get_line();
                if (flags & SKIPPRINT)
                        puts(curline);
                if (c == EOF)
                        return;
        }
        get_line();
        if (flags & NOARGS && curlen < owidth)
                flags |= ONEPERLINE;
        if (flags & ONEPERLINE)
                icols = 1;
        else                            /* count cols on first line */
                for (p = curline, endp = curline + curlen; p < endp; p++) {
                        if (*p == isep && multisep)
                                continue;
                        icols++;
                        while (*p && *p != isep)
                                p++;
                }
        do {
                if (flags & ONEPERLINE) {
                        elem.push_back(curline);
                        if (maxlen < curlen)
                                maxlen = curlen;
                        irows++;
                        continue;
                }
                for (p = curline, endp = curline + curlen; p < endp; p++) {
                        if (*p == isep && multisep)
                                continue;       /* eat up column separators */
                        if (*p == isep)         /* must be an empty column */
                                elem.push_back(blank);
                        else                    /* store column entry */
                                elem.push_back(p);
                        sp = p;
                        while (p < endp && *p != isep)
                                p++;            /* find end of entry */
                        *p = '\0';              /* mark end of entry */
                        len = p - sp;
                        if (maxlen < len)       /* update maxlen */
                                maxlen = len;
                }
                irows++;                        /* update row count */
                if (nullpad) {                  /* pad missing entries */
                        padto = irows * icols;
                        elem.resize(padto, blank);
                }
        } while (get_line() != EOF);
}

static void
putfile(void)
{
        size_t i, j, k;

        if (flags & TRANSPOSE)
                for (i = 0; i < orows; i++) {
                        for (j = i; j < elem.size(); j += orows)
                                prints(elem[j], (j - i) / orows);
                        putchar('\n');
                }
        else
                for (i = k = 0; i < orows; i++) {
                        for (j = 0; j < ocols; j++, k++)
                                if (k < elem.size())
                                        prints(elem[k], j);
                        putchar('\n');
                }
}

static void
prints(char *s, int col)
{
        int n;
        char *p = s;

        while (*p)
                p++;
        n = (flags & ONEOSEPONLY ? 1 : colwidths[col] - (p - s));
        if (flags & RIGHTADJUST)
                while (n-- > 0)
                        putchar(osep);
        for (p = s; *p; p++)
                putchar(*p);
        while (n-- > 0)
                putchar(osep);
}

static void
usage(void)
{
        fprintf(stderr,
                "usage: rs [-[csCS][x][kKgGw][N]tTeEnyjhHmz] [rows [cols]]\n");
        exit(1);
}

static void
prepfile(void)
{
        size_t i, j;
        size_t colw, max, n, orig_size, padto;

        if (elem.empty())
                exit(0);
        gutter += maxlen * propgutter / 100.0;
        colw = maxlen + gutter;
        if (flags & MTRANSPOSE) {
                orows = icols;
                ocols = irows;
        }
        else if (orows == 0 && ocols == 0) {    /* decide rows and cols */
                ocols = owidth / colw;
                if (ocols == 0) {
                        warnx("display width %zu is less than column width %zu",
                                        owidth, colw);
                        ocols = 1;
                }
                if (ocols > elem.size())
                        ocols = elem.size();
                orows = elem.size() / ocols + (elem.size() % ocols ? 1 : 0);
        }
        else if (orows == 0)                    /* decide on rows */
                orows = elem.size() / ocols + (elem.size() % ocols ? 1 : 0);
        else if (ocols == 0)                    /* decide on cols */
                ocols = elem.size() / orows + (elem.size() % orows ? 1 : 0);
        padto = orows * ocols;
        orig_size = elem.size();
        if (flags & RECYCLE) {
                for (i = 0; elem.size() < padto; i++)
                        elem.push_back(elem[i % orig_size]);
        }
        if (!(colwidths = (short *) malloc(ocols * sizeof(short))))
                errx(1, "malloc");
        if (flags & SQUEEZE) {
                if (flags & TRANSPOSE) {
                        auto it = elem.begin();
                        for (i = 0; i < ocols; i++) {
                                max = 0;
                                for (j = 0; it != elem.end() && j < orows; j++)
                                        if ((n = strlen(*it++)) > max)
                                                max = n;
                                colwidths[i] = max + gutter;
                        }
                } else {
                        for (i = 0; i < ocols; i++) {
                                max = 0;
                                for (j = i; j < elem.size(); j += ocols)
                                        if ((n = strlen(elem[j])) > max)
                                                max = n;
                                colwidths[i] = max + gutter;
                        }
                }
        }
        /*      for (i = 0; i < orows; i++) {
                        for (j = i; j < elem.size(); j += orows)
                                prints(elem[j], (j - i) / orows);
                        putchar('\n');
                }
        else {
                auto it = elem.begin();
                for (i = 0; i < orows; i++) {
                        for (j = 0; j < ocols; j++)
                                prints(*it++, j);
                        putchar('\n');
                }*/
        else
                for (i = 0; i < ocols; i++)
                        colwidths[i] = colw;
        if (!(flags & NOTRIMENDCOL)) {
                if (flags & RIGHTADJUST)
                        colwidths[0] -= gutter;
                else
                        colwidths[ocols - 1] = 0;
        }
        /*for (i = 0; i < ocols; i++)
                warnx("%d is colwidths, nelem %zu", colwidths[i], elem.size());*/
}

#define BSIZE   (LINE_MAX * 2)
static char     ibuf[BSIZE];

static int
get_line(void)  /* get line; maintain curline, curlen; manage storage */
{
        static  int putlength;
        static  char *endblock = ibuf + BSIZE;
        char *p;
        int c, i;

        if (irows == 0) {
                curline = ibuf;
                putlength = flags & DETAILSHAPE;
        }
        else if (skip <= 0) {                   /* don't waste storage */
                curline += curlen + 1;
                if (putlength) {        /* print length, recycle storage */
                        printf(" %zu line %zu\n", curlen, irows);
                        curline = ibuf;
                }
        }
        if (!putlength && endblock - curline < LINE_MAX + 1) { /* need storage */
                /*ww = endblock-curline; tt += ww;*/
                /*printf("#wasted %d total %d\n",ww,tt);*/
                if (!(curline = (char *) malloc(BSIZE)))
                        errx(1, "file too large");
                endblock = curline + BSIZE;
                /*printf("#endb %d curline %d\n",endblock,curline);*/
        }
        for (p = curline, i = 0;; *p++ = c, i++) {
                if ((c = getchar()) == EOF)
                        break;
                if (i >= LINE_MAX)
                        errx(1, "maximum line length (%d) exceeded", LINE_MAX);
                if (c == '\n')
                        break;
        }
        *p = '\0';
        curlen = i;
        return(c);
}

static void
getargs(int ac, char *av[])
{
        long val;
        int ch;

        if (ac == 1) {
                flags |= NOARGS | TRANSPOSE;
        }

        while ((ch = getopt(ac, av, "C::EG:HK:S::Tc::eg:hjk:mns::tw:yz")) != -1)
                switch (ch) {
                case 'T':
                        flags |= MTRANSPOSE;
                        /* FALLTHROUGH */
                case 't':
                        flags |= TRANSPOSE;
                        break;
                case 'c':               /* input col. separator */
                        flags |= ONEISEPONLY;
                        /* FALLTHROUGH */
                case 's':               /* one or more allowed */
                        if (optarg != NULL)
                                isep = *optarg;
                        else
                                isep = '\t';    /* default is ^I */
                        break;
                case 'C':
                        flags |= ONEOSEPONLY;
                        /* FALLTHROUGH */
                case 'S':
                        if (optarg != NULL)
                                osep = *optarg;
                        else
                                osep = '\t';    /* default is ^I */
                        break;
                case 'w':               /* window width, default 80 */
                        val = getnum(optarg);
                        if (val <= 0)
                                errx(1, "width must be a positive integer");
                        owidth = val;
                        break;
                case 'K':                       /* skip N lines */
                        flags |= SKIPPRINT;
                        /* FALLTHROUGH */
                case 'k':                       /* skip, do not print */
                        skip = getnum(optarg);
                        if (skip < 1)
                                skip = 1;
                        break;
                case 'm':
                        flags |= NOTRIMENDCOL;
                        break;
                case 'g':               /* gutter space */
                        gutter = getnum(optarg);
                        break;
                case 'G':
                        propgutter = getnum(optarg);
                        break;
                case 'e':               /* each line is an entry */
                        flags |= ONEPERLINE;
                        break;
                case 'E':
                        flags |= ONEPERCHAR;
                        break;
                case 'j':                       /* right adjust */
                        flags |= RIGHTADJUST;
                        break;
                case 'n':       /* null padding for missing values */
                        flags |= NULLPAD;
                        break;
                case 'y':
                        flags |= RECYCLE;
                        break;
                case 'H':                       /* print shape only */
                        flags |= DETAILSHAPE;
                        /* FALLTHROUGH */
                case 'h':
                        flags |= SHAPEONLY;
                        break;
                case 'z':                       /* squeeze col width */
                        flags |= SQUEEZE;
                        break;
                /*case 'p':
                        ipagespace = atoi(optarg);      (default is 1)
                        break;*/
                default:
                        usage();
                }

        av += optind;
        ac -= optind;

        /*if (!osep)
                osep = isep;*/
        switch (ac) {
#if 0
        case 3:
                opages = atoi(av[2]);
                /* FALLTHROUGH */
#endif
        case 2:
                val = strtol(av[1], NULL, 10);
                if (val >= 0)
                        ocols = val;
                /* FALLTHROUGH */
        case 1:
                val = strtol(av[0], NULL, 10);
                if (val >= 0)
                        orows = val;
                /* FALLTHROUGH */
        case 0:
                break;
        default:
                errx(1, "too many arguments");
        }
}

static long
getnum(const char *p)
{
        char *ep;
        long val;

        val = strtol(p, &ep, 10);
        if (*ep != '\0')
                errx(1, "invalid integer %s", p);
        return (val);
}