/* This work is copyrighted. See COPYRIGHT.OLD & COPYRIGHT.NEW for   *
*  details. If they are missing then this copy is in violation of    *
*  the copyright conditions.                                        */

/*
**	lib_addch.c
**
**	The routine waddch().
**
*/

#include "curses.priv.h"
#include "unctrl.h"

int
waddch(WINDOW *win, chtype c)
{
int	x, y;
int	newx;
chtype	ch = c;

#if 0	
	/* enabling this causes tons of tracing output
	   and slow ncurses down to a crawl */
	T(("waddch(%x,%c (%x)) called", win, ch&A_CHARTEXT, ch));
#endif

	x = win->_curx;
	y = win->_cury;

	if (y > win->_maxy  ||  x > win->_maxx  ||  y < 0  ||  x < 0)
	    return(ERR);

	switch (ch&A_CHARTEXT) {
    	case '\t':
		for (newx = x + (8 - (x & 07)); x < newx; x++)
	    		if (waddch(win, ' ') == ERR)
				return(ERR);
		return(OK);
    	case '\n':
		wclrtoeol(win);
    	x = 0;
		goto newline;
    	case '\r':
		x = 0;
		break;
    	case '\b':
		if (--x < 0)
		    	x = 0;
		break;
    	default:
		if (ch < ' ')
		    	return(waddstr(win, unctrl(ch)));

		ch |= win->_attrs;

		if (win->_line[y][x] != ch) {
		    	if (win->_firstchar[y] == _NOCHANGE)
				win->_firstchar[y] = win->_lastchar[y] = x;
		    	else if (x < win->_firstchar[y])
				win->_firstchar[y] = x;
		    	else if (x > win->_lastchar[y])
				win->_lastchar[y] = x;

		}

		win->_line[y][x++] = ch;
		if (x > win->_maxx) {
		    	x = 0;
newline:
		    	y++;
		    	if (y > win->_regbottom) {
				y--;
				if (win->_scroll)
				    	scroll(win);
		    	}
		}
		break;
	}

	win->_curx = x;
	win->_cury = y;

	return(OK);
}