/* TTY input driver */
#include <stdio.h>
#include <ctype.h>
#include "config.h"

#define	NULLCHAR	(char *)0;
int ttymode;
#define	TTY_LIT	0		/* Send next char literally */
#define	TTY_RAW	1
#define TTY_COOKED	2

int ttyecho=1;
#define	TTY_NOECHO	0
#define	TTY_ECHO	1

#ifdef	FLOW
int ttyflow=1;
#endif

#define	LINESIZE	256

#define CTLR	18
#define	CTLU	21
#define	CTLV	22
#define	CTLW	23
#define	CTLZ	26
#define	RUBOUT	127

raw()
{
	ttymode = TTY_RAW;
#ifdef	ATARI_ST
	set_stdout(ttymode);	/* CR/LF vs LF madness...  -- hyc */
#endif
}

cooked()
{
	ttymode = TTY_COOKED;
#ifdef	ATARI_ST
	set_stdout(ttymode);
#endif
}

void
echo()
{
	ttyecho = TTY_ECHO;
}

void
noecho()
{
	ttyecho = TTY_NOECHO;
}
 
/* Accept characters from the incoming tty buffer and process them
 * (if in cooked mode) or just pass them directly (if in raw mode).
 * Returns the number of characters available for use; if non-zero,
 * also stashes a pointer to the character(s) in the "buf" argument.
 */
 /*Control-R added by df for retype of lines - useful in Telnet */
 /*Then df got impatient and added Control-W for erasing words  */
 /* Control-V for the literal-next function, slightly improved
  * flow control, local echo stuff -- hyc */
int
ttydriv(c,buf)
char c;
char **buf;
{
	static char linebuf[LINESIZE];
	static char *cp = linebuf;
	char *rp ;
	int cnt;
	int seenprint;

	if(buf == (char **)NULL)
		return 0;	/* paranoia check */

	cnt = 0;
	switch(ttymode){
	case TTY_LIT:
		ttymode = TTY_COOKED;	/* Reset to cooked mode */
	case TTY_RAW:
		*cp++ = c;
		cnt = cp - linebuf;
		cp = linebuf;
		break;
	case TTY_COOKED:
		/* Perform cooked-mode line editing */
#ifdef PC9801
		switch(c){
#else
		switch(c & 0x7f){
#endif
		case '\r':	/* CR and LF are equivalent */
		case '\n':
			*cp++ = '\r';
			*cp++ = '\n';
			printf("\n");
			cnt = cp - linebuf;
			cp = linebuf;
			break;
		case RUBOUT:
		case '\b':		/* Backspace */
			if(cp != linebuf){
				cp--;
				if (ttyecho)
					printf("\b \b");
			}
			break;
		case CTLR:	/* print line buffer */
			if(ttyecho)
				printf("^R");
			printf("\n");
			if(ttyecho) {
				rp = linebuf ;
				while (rp < cp)
					putchar(*rp++) ;
			}
			break ;
		case CTLU:	/* Line kill */
			if(ttyecho) {
				while(cp != linebuf){
					cp--;
					printf("\b \b");
				}
			} else
				cp = linebuf;
			break;
		case CTLV:
			ttymode = TTY_LIT;
			break;
		case CTLW:	/* erase word */
			seenprint = 0 ;	/* we haven't seen a printable char yet */
			while (cp != linebuf) {
				cp--;
				if(ttyecho)
					printf("\b \b") ;
				if (isspace(*cp)) {
					if (seenprint)
						break ;
				}
				else
					seenprint = 1 ;
			}
			break ;
		default:	/* Ordinary character */
			*cp++ = c;
#ifndef	AMIGA
			/* ^Z apparently hangs the terminal emulators under
			 * DoubleDos and Desqview. I REALLY HATE having to patch
			 * around other people's bugslike this!!!
			 */
			if (ttyecho && (c != CTLZ))
				putchar(c);
#endif
			if(cp >= &linebuf[LINESIZE]){
				cnt = cp - linebuf;
				cp = linebuf;
			}
			break;
		}
	}
	if(cnt > 0)
		*buf = linebuf;
	else
		*buf = NULLCHAR;
#ifdef	FLOW
	if(cp > linebuf)
		ttyflow = 0;
	else
		ttyflow = 1;
#endif
	fflush(stdout);
	return cnt;
}