/*
 * Copyright (c) 1980, 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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.
 */

/*
 * 1999-02-22 Arkadiusz Miśkiewicz <misiek@pld.ORG.PL>
 * 	added Native Language Support
 * 1999-09-19 Bruno Haible <haible@clisp.cons.org>
 * 	modified to work correctly in multi-byte locales
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>		/* for close() */
#include <string.h>
#include <getopt.h>
#include "nls.h"

#include "widechar.h"
#include "c.h"
#include "closestream.h"

int plus(wchar_t c, wchar_t d);
void move(int l, int m);
void pflush(int ol);
static void __attribute__ ((__noreturn__)) usage(FILE * out);

/*
 * colcrt - replaces col for crts with new nroff esp. when using tbl.
 * Bill Joy UCB July 14, 1977
 *
 * This filter uses a screen buffer, 267 half-lines by 132 columns.
 * It interprets the up and down sequences generated by the new
 * nroff when used with tbl and by \u \d and \r.
 * General overstriking doesn't work correctly.
 * Underlining is split onto multiple lines, etc.
 *
 * Option - suppresses all underlining.
 * Option -2 forces printing of all half lines.
 */

#define FLUSH_SIZE 62
#define PAGE_ARRAY_ROWS 267
#define PAGE_ARRAY_COLS 132
wchar_t	page[PAGE_ARRAY_ROWS + 1][PAGE_ARRAY_COLS + 1];

int	outline = 1;
int	outcol;

char	suppresul;
char	printall;

void colcrt(FILE *f);

int main(int argc, char **argv) {
	FILE *f;
	int i, opt;
	enum { NO_UL_OPTION = CHAR_MAX + 1 };

	static const struct option longopts[] = {
		{ "no-underlining",	no_argument, 0, NO_UL_OPTION },
		{ "half-lines",		no_argument, 0, '2' },
		{ "version",		no_argument, 0, 'V' },
		{ "help",		no_argument, 0, 'h' },
		{ NULL, 0, 0, 0}
	};

	setlocale(LC_ALL, "");
	bindtextdomain(PACKAGE, LOCALEDIR);
	textdomain(PACKAGE);
	atexit(close_stdout);

	/* Take care of lonely hyphen option. */
	for (i = 0; i < argc; i++)
		if (argv[i][0] == '-' && argv[i][1] == '\0') {
			suppresul = 1;
			argc--;
			memmove(argv + i, argv + i + 1,
				sizeof(char *) * (argc - i));
			i--;
		}

	while ((opt = getopt_long(argc, argv, "2Vh", longopts, NULL)) != -1)
		switch (opt) {
			case NO_UL_OPTION:
				suppresul = 1;
				break;
			case '2':
				printall = 1;
				break;
			case 'V':
				printf(UTIL_LINUX_VERSION);
				return EXIT_SUCCESS;
			case 'h':
				usage(stdout);
			default:
				usage(stderr);
		}
	argc -= optind;
	argv += optind;

	do {
		if (argc > 0) {
			if (!(f = fopen(argv[0], "r"))) {
				fflush(stdout);
				err(EXIT_FAILURE, "%s", argv[0]);
			}
			argc--;
			argv++;
		} else {
			f = stdin;
		}
		colcrt(f);
		if (f != stdin)
			fclose(f);
	} while (argc > 0);
	fflush(stdout);
	return EXIT_SUCCESS;
}

void colcrt(FILE *f) {
	wint_t c;
	wchar_t *cp, *dp;
	int i, w;

	for (;;) {
		c = getwc(f);
		if (c == WEOF) {
			pflush(outline);
			fflush(stdout);
			break;
		}
		switch (c) {
		case '\n':
			if (outline >= (PAGE_ARRAY_ROWS - 2))
				pflush(FLUSH_SIZE);
			outline += 2;
			outcol = 0;
			continue;
		case '\016':
		case '\017':
			continue;
		case 033:
			c = getwc(f);
			switch (c) {
			case '9':
				if (outline >= (PAGE_ARRAY_ROWS - 1))
					pflush(FLUSH_SIZE);
				outline++;
				continue;
			case '8':
				if (outline >= 1)
					outline--;
				continue;
			case '7':
				outline -= 2;
				if (outline < 0)
					outline = 0;
				continue;
			default:
				continue;
			}
		case '\b':
			if (outcol)
				outcol--;
			continue;
		case '\t':
			outcol += 8;
			outcol &= ~7;
			outcol--;
			c = ' ';
			/* fallthrough */
		default:
			w = wcwidth(c);
			if (w < 0)
				continue;
			if (outcol + w > PAGE_ARRAY_COLS) {
				outcol++;
				continue;
			}
			cp = &page[outline][outcol];
			outcol += w;
			if (c == '_') {
				if (suppresul)
					continue;
				cp += PAGE_ARRAY_COLS;
				c = '-';
			}
			if (*cp == 0) {
				/* trick! */
				for (i = 0; i < w; i++)
					cp[i] = c;
				dp = cp - (outcol - w);
				for (cp--; cp >= dp && *cp == 0; cp--)
					*cp = ' ';
			} else {
				if (plus(c, *cp) || plus(*cp, c))
					*cp = '+';
				else if (*cp == ' ' || *cp == 0) {
					for (i = 1; i < w; i++)
						if (cp[i] != ' ' && cp[i] != 0)
							continue;
					for (i = 0; i < w; i++)
						cp[i] = c;
				}
			}
			continue;
		}
	}
}

int plus(wchar_t c, wchar_t d)
{

	return (c == '|' && (d == '-' || d == '_'));
}

int first;

void pflush(int ol)
{
	register int i;
	register wchar_t *cp;
	char lastomit;
	int l, w;

	l = ol;
	lastomit = 0;
	if (l > (PAGE_ARRAY_ROWS - 1))
		l = PAGE_ARRAY_ROWS - 1;
	else
		l |= 1;
	for (i = first | 1; i < l; i++) {
		move(i, i - 1);
		move(i, i + 1);
	}
	for (i = first; i < l; i++) {
		cp = page[i];
		if (printall == 0 && lastomit == 0 && *cp == 0) {
			lastomit = 1;
			continue;
		}
		lastomit = 0;
		while (*cp) {
			if ((w = wcwidth(*cp)) > 0) {
				putwchar(*cp);
				cp += w;
			} else
				cp++;
		}
		putwchar('\n');
	}
	memmove(page, page[ol], (PAGE_ARRAY_ROWS - ol) * PAGE_ARRAY_COLS * sizeof(wchar_t));
	memset(page[PAGE_ARRAY_ROWS - ol], '\0', ol * PAGE_ARRAY_COLS * sizeof(wchar_t));
	outline -= ol;
	outcol = 0;
	first = 1;
}

void move(int l, int m)
{
	register wchar_t *cp, *dp;

	for (cp = page[l], dp = page[m]; *cp; cp++, dp++) {
		switch (*cp) {
			case '|':
				if (*dp != ' ' && *dp != '|' && *dp != 0)
					return;
				break;
			case ' ':
				break;
			default:
				return;
		}
	}
	if (*cp == 0) {
		for (cp = page[l], dp = page[m]; *cp; cp++, dp++)
			if (*cp == '|')
				*dp = '|';
			else if (*dp == 0)
				*dp = ' ';
		page[l][0] = 0;
	}
}

static void __attribute__ ((__noreturn__)) usage(FILE * out)
{
	fputs(USAGE_HEADER, out);
	fprintf(out, _(" %s [options] [<file>...]\n"), program_invocation_short_name);

	fputs(USAGE_SEPARATOR, out);
	fputs(_("Filter nroff output for CRT previewing.\n"), out);

	fputs(USAGE_OPTIONS, out);
	fputs(_(" -,  --no-underlining    suppress all underlining\n"), out);
	fputs(_(" -2, --half-lines        print all half-lines\n"), out);

	fputs(USAGE_SEPARATOR, out);
	fputs(USAGE_HELP, out);
	fputs(USAGE_VERSION, out);
	fprintf(out, USAGE_MAN_TAIL("colcrt(1)"));

	exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
}
