/* term.c */

/*			   NOTICE
 *
 * Copyright (c) 1990,1992,1993 Britt Yenne.  All rights reserved.
 * 
 * This software is provided AS-IS.  The author gives no warranty,
 * real or assumed, and takes no responsibility whatsoever for any 
 * use or misuse of this software, or any damage created by its use
 * or misuse.
 * 
 * This software may be freely copied and distributed provided that
 * no part of this NOTICE is deleted or edited in any manner.
 * 
 */

/* Mail comments or questions to ytalk@austin.eds.com */

#include "header.h"
#ifdef USE_SGTTY
# include <sys/ioctl.h>
# ifdef hpux
#  include <sys/bsdtty.h>
#  include <sgtty.h>
# endif
#else
# include <termios.h>
#endif
#include "cwin.h"
#include "xwin.h"
#include "menu.h"

static int  (*_open_term)();	/* open a new terminal */
static void (*_close_term)();	/* close a terminal */
static void (*_addch_term)();	/* write a char to a terminal */
static void (*_move_term)();	/* move cursor to Y,X position */
static void (*_clreol_term)();	/* clear to end of line */
static void (*_clreos_term)();	/* clear to end of screen */
static void (*_scroll_term)();	/* scroll up one line */
static void (*_rev_scroll_term)(); /* scroll down one line */
static void (*_flush_term)();	/* flush pending output */

static int term_type = 0;
#ifdef USE_SGTTY
 static int line_discipline;
 static int local_mode;
 static struct sgttyb sgttyb;
 static struct tchars tchars;
 static struct ltchars ltchars;
#else
 static struct termios tio;
#endif

#ifdef USE_SGTTY
static void
init_sgtty()
{
    if(ioctl(0, TIOCGETD, &line_discipline) < 0)
    {
	show_error("TIOCGETD");
	bail(YTE_INIT);
    }
    if(ioctl(0, TIOCLGET, &local_mode) < 0)
    {
	show_error("TIOCGETP");
	bail(YTE_INIT);
    }
    if(ioctl(0, TIOCGETP, &sgttyb) < 0)
    {
	show_error("TIOCGETP");
	bail(YTE_INIT);
    }
    if(ioctl(0, TIOCGETC, &tchars) < 0)
    {
	show_error("TIOCGETC");
	bail(YTE_INIT);
    }
    if(ioctl(0, TIOCGLTC, &ltchars) < 0)
    {
	show_error("TIOCGLTC");
	bail(YTE_INIT);
    }
    me->old_rub = sgttyb.sg_erase;
    me->RUB  = RUBDEF;
    me->KILL = sgttyb.sg_kill;
    me->WORD = ltchars.t_werasc;
    me->CLR = '\024';		/* ^T */
}
#else
static void
init_termios()
{
    /* get edit chars */

    if(tcgetattr(0, &tio) < 0)
    {
	show_error("tcgetattr failed");
	bail(YTE_INIT);
    }
    me->old_rub = tio.c_cc[VERASE];
    me->RUB  = RUBDEF;
#ifdef VKILL
    me->KILL = tio.c_cc[VKILL];
#else
    me->KILL = '\025';	/* ^U */
#endif
#ifdef VWERASE
    me->WORD = tio.c_cc[VWERASE];
    if(me->WORD == 0xff)
	me->WORD = '\027';	/* ^W */
#else
    me->WORD = '\027';	/* ^W */
#endif
    me->CLR = '\024';		/* ^T */
}
#endif

/* Initialize terminal and input characteristics.
 */
void
init_term()
{
    char tmpstr[64];

#ifdef USE_SGTTY
    init_sgtty();
#else
    init_termios();
#endif

    /* Decide on a terminal (window) system and set up the
     * function pointers.
     */

    term_type = 0;	/* nothing selected yet */

#ifdef USE_X11
    if(term_type == 0 && (def_flags & FL_XWIN) && getenv("DISPLAY"))
    {
	_open_term = open_xwin;
	_close_term = close_xwin;
	_addch_term = addch_xwin;
	_move_term = move_xwin;
	_clreol_term = clreol_xwin;
	_clreos_term = clreos_xwin;
	_scroll_term = scroll_xwin;
	_rev_scroll_term = rev_scroll_xwin;
	_flush_term = flush_xwin;
	init_xwin();
	term_type = 2;	/* using xwin */
    }
#endif

    /* if no window system found, default to curses */
     
    if(term_type == 0)
    {
	_open_term = open_curses;
	_close_term = close_curses;
	_addch_term = addch_curses;
	_move_term = move_curses;
	_clreol_term = clreol_curses;
	_clreos_term = clreos_curses;
	_scroll_term = scroll_curses;
	_rev_scroll_term = NULL;
	_flush_term = flush_curses;
	init_curses();
	term_type = 1;	/* using curses */
    }

    /* set me up a terminal */

    sprintf(tmpstr, "YTalk version %d.%d (%d)", VMAJOR, VMINOR, VPATCH);
    if(open_term(me, tmpstr) < 0)
    {
	end_term();
	show_error("init_term: open_term() failed");
	bail(0);
    }
}

/* Set terminal size.
 */
void
set_terminal_size(fd, rows, cols)
  int fd, rows, cols;
{
#ifdef TIOCSWINSZ
    struct winsize winsize;

    winsize.ws_row = rows;
    winsize.ws_col = cols;
    ioctl(fd, TIOCSWINSZ, &winsize);
#endif
}

/* Set terminal and input characteristics for slave terminals.
 */
void
set_terminal_flags(fd)
  int fd;
{
#ifdef USE_SGTTY
    (void)ioctl(fd, TIOCSETD, &line_discipline);
    (void)ioctl(fd, TIOCLSET, &local_mode);
    (void)ioctl(fd, TIOCSETP, &sgttyb);
    (void)ioctl(fd, TIOCSETC, &tchars);
    (void)ioctl(fd, TIOCSLTC, &ltchars);
#else
    if(tcsetattr(fd, TCSANOW, &tio) < 0)
	show_error("tcsetattr failed");
#endif
}

int
what_term()
{
    return term_type;
}

/* Abort all terminal processing.
 */
void
end_term()
{
    switch(term_type)
    {
	case 1:		/* curses */
	    end_curses();
	    break;
#ifdef USE_X11
	case 2:		/* xwin */
	    end_xwin();
	    break;
#endif
    }
    term_type = 0;
}

/* Open a new user window.
 */
int
open_term(user, title)
  register yuser *user;
  register char *title;
{
    if(_open_term(user, title) != 0)
	return -1;
    user->x = user->y = 0;
    if(user->scr == NULL)
	resize_win(user, 24, 80);
    return 0;
}

/* Close a user window.
 */
void
close_term(user)
  register yuser *user;
{
    register int i;

    if(user->scr)
    {
	_close_term(user);
	for(i = 0; i < user->t_rows; i++)
	    free(user->scr[i]);
	free(user->scr);
	user->scr = NULL;
	user->t_rows = user->rows = 0;
	user->t_cols = user->cols = 0;
    }
}

/* Place a character.
 */
void
addch_term(user, c)
  register yuser *user;
  register ychar c;
{
    if(c >= ' ' && c <= '~')
    {
	_addch_term(user, c);
	user->scr[user->y][user->x] = c;
	if(++(user->x) >= user->cols)
	{
	    user->bump = 1;
	    user->x = user->cols - 1;
	    if(user->cols < user->t_cols)
		_move_term(user, user->y, user->x);
	}
    }
}

/* Move the cursor.
 */
void
move_term(user, y, x)
  register yuser *user;
  register int y, x;
{
    if(y < 0 || y >= user->rows)
	y = user->rows - 1;
    if(x < 0 || x >= user->cols)
    {
	user->bump = 1;
	x = user->cols - 1;
    }
    else
	user->bump = 0;
    _move_term(user, y, x);
    user->y = y;
    user->x = x;
}

/* Clear to EOL.
 */
void
clreol_term(user)
  register yuser *user;
{
    register int j;
    register ychar *c;

    if(user->cols < user->t_cols)
    {
	c = user->scr[user->y] + user->x;
	for(j = user->x; j < user->cols; j++)
	{
	    *(c++) = ' ';
	    _addch_term(user, ' ');
	}
	move_term(user, user->y, user->x);
    }
    else
    {
	_clreol_term(user);
	c = user->scr[user->y] + user->x;
	for(j = user->x; j < user->cols; j++)
	    *(c++) = ' ';
    }
}

/* Clear to EOS.
 */
void
clreos_term(user)
  register yuser *user;
{
    register int j, i;
    register ychar *c;
    int x, y;

    if(user->cols < user->t_cols || user->rows < user->t_rows)
    {
	x = user->x;
	y = user->y;
	clreol_term(user);
	for(i = user->y + 1; i < user->rows; i++)
	{
	    move_term(user, i, 0);
	    clreol_term(user);
	}
	move_term(user, y, x);
    }
    else
    {
	_clreos_term(user);
	j = user->x;
	for(i = user->y; i < user->rows; i++)
	{
	    c = user->scr[i] + j;
	    for(; j < user->cols; j++)
		*(c++) = ' ';
	    j = 0;
	}
    }
}

/* Scroll window.
 */
void
scroll_term(user)
  register yuser *user;
{
    register int i;
    register ychar *c;
    int sy, sx;

    if(user->sc_bot > user->sc_top)
    {
	c = user->scr[user->sc_top];
	for(i = user->sc_top; i < user->sc_bot; i++)
	    user->scr[i] = user->scr[i+1];
	user->scr[user->sc_bot] = c;
	for(i = 0; i < user->cols; i++)
	    *(c++) = ' ';
	if(_scroll_term
	&& user->rows == user->t_rows
	&& user->cols == user->t_cols
	&& user->sc_top == 0
	&& user->sc_bot == user->rows - 1)
	    _scroll_term(user);
	else
	    redraw_term(user, 0);
    }
    else
    {
	sy = user->y;
	sx = user->x;
	move_term(user, user->sc_top, 0);
	clreol_term(user);
	move_term(user, sy, sx);
    }
}

/* Reverse-scroll window.
 */
void
rev_scroll_term(user)
  register yuser *user;
{
    register int i;
    register ychar *c;
    int sy, sx;

    if(user->sc_bot > user->sc_top)
    {
	c = user->scr[user->sc_bot];
	for(i = user->sc_bot; i > user->sc_top; i--)
	    user->scr[i] = user->scr[i-1];
	user->scr[user->sc_top] = c;
	for(i = 0; i < user->cols; i++)
	    *(c++) = ' ';
	if(_rev_scroll_term
	&& user->rows == user->t_rows
	&& user->cols == user->t_cols
	&& user->sc_top == 0
	&& user->sc_bot == user->rows - 1)
	    _rev_scroll_term(user);
	else
	    redraw_term(user, 0);
    }
    else
    {
	sy = user->y;
	sx = user->x;
	move_term(user, user->sc_top, 0);
	clreol_term(user);
	move_term(user, sy, sx);
    }
}

/* Flush window output.
 */
void
flush_term(user)
  register yuser *user;
{
    _flush_term(user);
}

/* Rub one character.
 */
void
rub_term(user)
  register yuser *user;
{
    if(user->x > 0)
    {
	if(user->bump)
	{
	    addch_term(user, ' ');
	    user->bump = 0;
	}
	else
	{
	    move_term(user, user->y, user->x - 1);
	    addch_term(user, ' ');
	    move_term(user, user->y, user->x - 1);
	}

    }
}

/* Rub one word.
 */
int
word_term(user)
  register yuser *user;
{
    register int x, out;

    for(x = user->x - 1; x >= 0 && user->scr[user->y][x] == ' '; x--)
	continue;
    for(; x >= 0 && user->scr[user->y][x] != ' '; x--)
	continue;
    out = user->x - (++x);
    if(out <= 0)
	return 0;
    move_term(user, user->y, x);
    clreol_term(user);
    return out;
}

/* Kill current line.
 */
void
kill_term(user)
  register yuser *user;
{
    if(user->x > 0)
    {
	move_term(user, user->y, 0);
	clreol_term(user);
    }
}

/* Expand a tab.  We use non-destructive tabs.
 */
void
tab_term(user)
  register yuser *user;
{
    move_term(user, user->y, (user->x + 8) & 0xfff8);
}

/* Process a newline.
 */
void
newline_term(user)
  register yuser *user;
{
    register int new_y, next_y;

    new_y = user->y + 1;
    if(user->flags & FL_RAW)
    {
	if(new_y >= user->rows)
	{
	    if(user->flags & FL_SCROLL)
		scroll_term(user);
	}
	else
	    move_term(user, new_y, user->x);
    }
    else
    {
	if(new_y >= user->rows)
	{
	    if(user->flags & FL_SCROLL)
	    {
		scroll_term(user);
		move_term(user, user->y, 0);
		return;
	    }
	    new_y = 0;
	}
	next_y = new_y + 1;
	if(next_y >= user->rows)
	    next_y = 0;
	if(next_y > 0 || !(user->flags & FL_SCROLL))
	{
	    move_term(user, next_y, 0);
	    clreol_term(user);
	}
	move_term(user, new_y, 0);
	clreol_term(user);
    }
}

/* Insert lines.
 */
void
add_line_term(user, num)
  register yuser *user;
  int num;
{
    register ychar *c;
    register int i;

    if(num == 1 && user->y == 0)
	rev_scroll_term(user);
    else
    {
	/* find number of remaining lines */

	i = user->rows - user->y - num;
	if(i <= 0)
	{
	    i = user->x;
	    move_term(user, user->y, 0);
	    clreos_term(user);
	    move_term(user, user->y, i);
	    return;
	}

	/* swap the remaining lines to bottom */

	for(i--; i >= 0; i--)
	{
	    c = user->scr[user->y + i];
	    user->scr[user->y + i] = user->scr[user->y + i + num];
	    user->scr[user->y + i + num] = c;
	}

	/* clear the added lines */

	for(num--; num >= 0; num--)
	{
	    c = user->scr[user->y + num];
	    for(i = 0; i < user->cols; i++)
		*(c++) = ' ';
	}
	redraw_term(user, user->y);
    }
}

/* Delete lines.
 */
void
del_line_term(user, num)
  register yuser *user;
  int num;
{
    register ychar *c;
    register int i;

    if(num == 1 && user->y == 0)
	scroll_term(user);
    else
    {
	/* find number of remaining lines */

	i = user->rows - user->y - num;
	if(i <= 0)
	{
	    i = user->x;
	    move_term(user, user->y, 0);
	    clreos_term(user);
	    move_term(user, user->y, i);
	    return;
	}

	/* swap the remaining lines to top */

	for(; i > 0; i--)
	{
	    c = user->scr[user->rows - i];
	    user->scr[user->rows - i] = user->scr[user->rows - i - num];
	    user->scr[user->rows - i - num] = c;
	}

	/* clear the remaining bottom lines */

	for(; num > 0; num--)
	{
	    c = user->scr[user->rows - num];
	    for(i = 0; i < user->cols; i++)
		*(c++) = ' ';
	}
	redraw_term(user, user->y);
    }
}

static void
copy_text(fr, to, count)
  register ychar *fr, *to;
  register int count;
{
    if(to < fr)
    {
	for(; count > 0; count--)
	    *(to++) = *(fr++);
    }
    else
    {
	fr += count;
	to += count;
	for(; count > 0; count--)
	    *(--to) = *(--fr);
    }
}

/* Add chars.
 */
void
add_char_term(user, num)
  register yuser *user;
  int num;
{
    register ychar *c;
    register int i;

    /* find number of remaining non-blank chars */

    i = user->cols - user->x - num;
    c = user->scr[user->y] + user->cols - num - 1;
    while(i > 0 && *c == ' ')
	c--, i--;
    if(i <= 0)
    {
	clreol_term(user);
	return;
    }

    /* transfer the chars and clear the remaining */

    c++;
    copy_text(c - i, c - i + num, i);
    for(c -= i; num > 0; num--)
    {
	*(c++) = ' ';
	_addch_term(user, ' ');
    }
    for(; i > 0; i--)
	_addch_term(user, *(c++));
    _move_term(user, user->y, user->x);
}

/* Delete chars.
 */
void
del_char_term(user, num)
  register yuser *user;
  int num;
{
    register ychar *c;
    register int i;

    /* find number of remaining non-blank chars */

    i = user->cols - user->x - num;
    c = user->scr[user->y] + user->cols - 1;
    while(i > 0 && *c == ' ')
	c--, i--;
    if(i <= 0)
    {
	clreol_term(user);
	return;
    }

    /* transfer the chars and clear the remaining */

    c++;
    copy_text(c - i, c - i - num, i);
    for(c -= (i + num); i > 0; i--)
	_addch_term(user, *(c++));
    for(; num > 0; num--)
    {
	*(c++) = ' ';
	_addch_term(user, ' ');
    }
    _move_term(user, user->y, user->x);
}

/* Redraw a user's window.
 */
void
redraw_term(user, y)
  register yuser *user;
  register int y;
{
    register int x, spaces;
    register ychar *c;

    for(; y < user->t_rows; y++)
    {
	_move_term(user, y, 0);
	_clreol_term(user);
	spaces = 0;
	c = user->scr[y];
	for(x = 0; x < user->t_cols; x++, c++)
	{
	    if(*c == ' ')
		spaces++;
	    else
	    {
		if(spaces)
		{
		    if(spaces <= 3)	/* arbitrary */
		    {
			for(; spaces > 0; spaces--)
			    _addch_term(user, ' ');
		    }
		    else
		    {
			_move_term(user, y, x);
			spaces = 0;
		    }
		}
		_addch_term(user, *c);
	    }
	}
    }

    /* redisplay any active menu */

    if(menu_ptr != NULL)
	update_menu();
    else
	_move_term(user, user->y, user->x);
}

/* Return the first interesting row for a user with a window of
 * the given height and width.
 */
static int
first_interesting_row(user, height, width)
  yuser *user;
  int height, width;
{
    register int j, i;
    register ychar *c;

    if(height < user->t_rows)
    {
	j = (user->y + 1) - height;
	if(j < 0)
	    j += user->t_rows;
    }
    else
    {
	j = user->y + 1;
	if(j >= user->t_rows)
	    j = 0;
    }
    while(j != user->y)
    {
	i = (width > user->t_cols) ? user->t_cols : width;
	for(c = user->scr[j]; i > 0; i--, c++)
	    if(*c != ' ')
		break;
	if(i > 0)
	    break;
	if(++j >= user->t_rows)
	    j = 0;
    }
    return j;
}

/* Called when a user's window has been resized.
 */
void
resize_win(user, height, width)
  yuser *user;
  int height, width;
{
    register int j, i;
    register ychar *c, **newscr;
    int new_y, y_pos;

    if(height == user->t_rows && width == user->t_cols)
	return;

    /* resize the user terminal buffer */

    new_y = -1;
    y_pos = 0;
    newscr = (ychar **)get_mem(height * sizeof(ychar *));
    if(user->scr == NULL)
    {
	user->t_rows = user->rows = 0;
	user->t_cols = user->cols = 0;
    }
    else if(user->region_set)
    {
	/* save as many top lines as possible */

	for(j = 0; j < height && j < user->t_rows; j++)
	    newscr[j] = user->scr[j];
	new_y = j - 1;
	y_pos = user->y;
	for(; j < user->t_rows; j++)
	    free(user->scr[j]);
	free(user->scr);
    }
    else
    {
	/* shift all recent lines to top of screen */

	j = first_interesting_row(user, height, width);
	for(i = 0; i < height; i++)
	{
	    newscr[++new_y] = user->scr[j];
	    if(j == user->y)
		break;
	    if(++j >= user->t_rows)
		j = 0;
	}
	for(i++; i < user->t_rows; i++)
	{
	    if(++j >= user->t_rows)
		j = 0;
	    free(user->scr[j]);
	}
	y_pos = new_y;
	free(user->scr);
    }
    user->scr = newscr;

    /* fill in the missing portions */

    if(width > user->t_cols)
	for(i = 0; i <= new_y; i++)
	{
	    user->scr[i] = (ychar *)realloc_mem(user->scr[i], width);
	    for(j = user->t_cols; j < width; j++)
		user->scr[i][j] = ' ';
	}
    for(i = new_y + 1; i < height; i++)
    {
	c = user->scr[i] = (ychar *)get_mem(width);
	for(j = 0; j < width; j++)
	    *(c++) = ' ';
    }

    /* reset window values */

    user->t_rows = user->rows = height;
    user->t_cols = user->cols = width;
    user->sc_top = 0;
    user->sc_bot = height - 1;
    move_term(user, y_pos, user->x);
    send_winch(user);
    redraw_term(user, 0);
    flush_term(user);
}

/* Draw a nice box.
 */
static void
draw_box(user, height, width, c)
  yuser *user;
  int height, width;
  char c;
{
    register int i;

    if(width < user->t_cols)
    {
	for(i = 0; i < height; i++)
	{
	    move_term(user, i, width);
	    addch_term(user, c);
	    if(width + 1 < user->t_cols)
		clreol_term(user);
	}
    }
    if(height < user->t_rows)
    {
	move_term(user, height, 0);
	for(i = 0; i < width; i++)
	    addch_term(user, c);
	if(width < user->t_cols)
	    addch_term(user, c);
	if(width + 1 < user->t_cols)
	    clreol_term(user);
	if(height + 1 < user->t_rows)
	{
	    move_term(user, height + 1, 0);
	    clreos_term(user);
	}
    }
}

/* Set the virtual terminal size, ie: the display region.
 */
void
set_win_region(user, height, width)
  yuser *user;
  int height, width;
{
    register int x, y;
    int old_height, old_width;

    if(height < 2 || height > user->t_rows)
	height = user->t_rows;
    if(width < 2 || width > user->t_cols)
	width = user->t_cols;

    /* Don't check if they're already equal; always perform processing.
     * Just because it's equal over here doesn't mean it's equal for all
     * ytalk connections.  We still need to clear the screen.
     */

    old_height = user->rows;
    old_width = user->cols;
    user->rows = user->t_rows;
    user->cols = user->t_cols;
    if(user->region_set)
    {
	x = user->x;
	y = user->y;
	if(width > old_width || height > old_height)
	    draw_box(user, old_height, old_width, ' ');
    }
    else
    {
	x = y = 0;
	move_term(user, 0, 0);
	clreos_term(user);
	user->region_set = 1;
    }
    draw_box(user, height, width, '%');

    /* set the display region */

    user->rows = height;
    user->cols = width;
    user->sc_top = 0;
    user->sc_bot = height - 1;
    move_term(user, y, x);
    flush_term(user);
    
    if(user == me)
	send_region();
}

/* Set the virtual terminal size, ie: the display region.
 */
void
end_win_region(user)
  yuser *user;
{
    int old_height, old_width;

    old_height = user->rows;
    old_width = user->cols;
    user->rows = user->t_rows;
    user->cols = user->t_cols;
    user->sc_top = 0;
    user->sc_bot = user->rows - 1;
    if(old_height < user->t_rows || old_width < user->t_cols)
	draw_box(user, old_height, old_width, ' ');
    user->region_set = 0;
    if(user == me)
	send_end_region();
}

/* Set the scrolling region.
 */
void
set_scroll_region(user, top, bottom)
  yuser *user;
  int top, bottom;
{
    if(top < 0 || top >= user->rows)
	return;
    if(bottom < top || bottom >= user->rows)
	return;
    user->sc_top = top;
    user->sc_bot = bottom;
}

/* Send a message to the terminal.
 */
void
msg_term(user, str)
  yuser *user;
  char *str;
{
    int y;

    if((y = user->y + 1) >= user->rows)
	y = 0;
    _move_term(user, y, 0);
    _addch_term(user, '[');
    while(*str)
	_addch_term(user, *(str++));
    _addch_term(user, ']');
    _clreol_term(user);
    _move_term(user, user->y, user->x);
    _flush_term(user);
}

/* Spew terminal contents to a file descriptor.
 */
void
spew_term(user, fd, rows, cols)
  yuser *user;
  int fd, rows, cols;
{
    register ychar *c, *e;
    register int len;
    int y;
    static char tmp[20];

    if(user->region_set)
    {
	y = 0;
	if(cols > user->cols)
	    cols = user->cols;
	if(rows > user->rows)
	    rows = user->rows;
	for(;;)
	{
	    for(c = e = user->scr[y], len = cols; len > 0; len--, c++)
		if(*c != ' ')
		    e = c + 1;
	    if(e != user->scr[y])
		(void)write(fd, user->scr[y], e - user->scr[y]);
	    if(++y >= rows)
		break;
	    (void)write(fd, "\n", 1);
	}

	/* move the cursor to the correct place */

	sprintf(tmp, "%c[%d;%dH", 27, user->y + 1, user->x + 1);
	(void)write(fd, tmp, strlen(tmp));
    }
    else
    {
	y = first_interesting_row(user, rows, cols);
	for(;;)
	{
	    if(y == user->y)
	    {
		if(user->x > 0)
		    (void)write(fd, user->scr[y], user->x);
		break;
	    }
	    for(c = e = user->scr[y], len = user->t_cols; len > 0; len--, c++)
		if(*c != ' ')
		    e = c + 1;
	    if(e != user->scr[y])
		(void)write(fd, user->scr[y], e - user->scr[y]);
	    (void)write(fd, "\n", 1);
	    if(++y >= user->t_rows)
		y = 0;
	}
    }
}

/* Draw some raw characters to the screen without updating any buffers.
 * Whoever uses this should know what they're doing.  It should always
 * be followed by a redraw_term() before calling any of the normal
 * term functions again.
 *
 * If the given string is not as long as the given length, then the
 * string is repeated to fill the given length.
 *
 * This is an unadvertised function.
 */
void
raw_term(user, y, x, str, len)
  yuser *user;
  int y, x;
  ychar *str;
  int len;
{
    register ychar *c;

    if(y < 0 || y >= user->t_rows)
	return;
    if(x < 0 || x >= user->t_cols)
	return;
    _move_term(user, y, x);

    for(c = str; len > 0; len--, c++)
    {
	if(*c == '\0')
	    c = str;
	if(*c < ' ' || *c > '~')
	    return;
	_addch_term(user, *c);
    }
}

int
center(width, n)
  int width, n;
{
    if(n >= width)
	return 0;
    return (width - n) >> 1;
}

void
redraw_all_terms()
{
    register yuser *u;

    switch(term_type)
    {
	case 1:		/* curses */
	    redisplay_curses();
	    break;
	default:
	    redraw_term(me, 0);
	    flush_term(me);
	    for(u = connect_list; u; u = u->next)
	    {
		redraw_term(u, 0);
		flush_term(u);
	    }
    }
}

void
set_raw_term()
{
    /* only some terminal systems need to do this */

    switch(term_type)
    {
	case 1:		/* curses */
	    set_raw_curses();
	    break;
    }
}

void
set_cooked_term()
{
    /* only some terminal systems need to do this */

    switch(term_type)
    {
	case 1:		/* curses */
	    set_cooked_curses();
	    break;
    }
}

int
term_does_asides()
{
    /* only some terminal systems can do this */

    switch(term_type)
    {
	case 2:		/* X11 */
	    return 1;
    }
    return 0;
}
