#include <arpa/telnet.h>

#include "externs.h"
#include "types.h"

char	ttyobuf[2*BUFSIZ], *tfrontp, *tbackp;

char
    termEofChar,
    termEraseChar,
    termFlushChar,
    termIntChar,
    termKillChar,
    termLiteralNextChar,
    termQuitChar;

/*
 * initialize the terminal data structures.
 */

init_terminal()
{
    tfrontp = tbackp = ttyobuf;
    autoflush = TerminalAutoFlush();
}


/*
 *		Send as much data as possible to the terminal.
 *
 *		The return value indicates whether we did any
 *	useful work.
 */


int
ttyflush()
{
    int n;

    if ((n = tfrontp - tbackp) > 0) {
	if (!(SYNCHing||flushout)) {
	    n = TerminalWrite(tout, tbackp, n);
	} else {
	    TerminalFlushOutput();
	    /* we leave 'n' alone! */
	}
    }
    if (n >= 0) {
	tbackp += n;
	if (tbackp == tfrontp) {
	    tbackp = tfrontp = ttyobuf;
	}
    }
    return n > 0;
}

#if	defined(TN3270)

#if	defined(unix)
static void
inputAvailable()
{
    HaveInput = 1;
}
#endif	/* defined(unix) */

void
outputPurge()
{
    int tmp = flushout;

    flushout = 1;

    ttyflush();

    flushout = tmp;
}

#endif	/* defined(TN3270) */

#if	defined(unix)
/*
 * Various signal handling routines.
 */

void
deadpeer()
{
	setcommandmode();
	longjmp(peerdied, -1);
}

void
intr()
{
    if (localchars) {
	intp();
	return;
    }
    setcommandmode();
    longjmp(toplevel, -1);
}

void
intr2()
{
    if (localchars) {
	sendbrk();
	return;
    }
}

void
doescape()
{
    command(0);
}
#endif	/* defined(unix) */

/*
 * These routines decides on what the mode should be (based on the values
 * of various global variables).
 */


int
getconnmode()
{
    static char newmode[16] =
			{ 4, 5, 3, 3, 2, 2, 1, 1, 6, 6, 6, 6, 6, 6, 6, 6 };
    int modeindex = 0;

    if (dontlecho && (clocks.echotoggle > clocks.modenegotiated)) {
	modeindex += 1;
    }
    if (hisopts[TELOPT_ECHO]) {
	modeindex += 2;
    }
    if (hisopts[TELOPT_SGA]) {
	modeindex += 4;
    }
    if (In3270) {
	modeindex += 8;
    }
    return newmode[modeindex];
}

void
setconnmode()
{
    TerminalNewMode(tin, tout, getconnmode());
}


void
setcommandmode()
{
    TerminalNewMode(tin, tout, 0);
}

#if	defined(TN3270)

/*
 * The following routines are places where the various tn3270
 * routines make calls into telnet.c.
 */

/* TtyChars() - returns the number of characters in the TTY buffer */
TtyChars()
{
    return(tfrontp-tbackp);
}

/*
 * DataToNetwork - queue up some data to go to network.  If "done" is set,
 * then when last byte is queued, we add on an IAC EOR sequence (so,
 * don't call us with "done" until you want that done...)
 *
 * We actually do send all the data to the network buffer, since our
 * only client needs for us to do that.
 */

int
DataToNetwork(buffer, count, done)
register char	*buffer;	/* where the data is */
register int	count;		/* how much to send */
int		done;		/* is this the last of a logical block */
{
    register int c;
    int origCount;
    fd_set o;

    origCount = count;
    FD_ZERO(&o);

    while (count) {
	if ((netobuf+sizeof netobuf - nfrontp) < 6) {
	    netflush();
	    while ((netobuf+sizeof netobuf - nfrontp) < 6) {
		FD_SET(net, &o);
		(void) select(net+1, (fd_set *) 0, &o, (fd_set *) 0,
						(struct timeval *) 0);
		netflush();
	    }
	}
	c = *buffer++;
	count--;
	if (c == IAC) {
	    *nfrontp++ = IAC;
	    *nfrontp++ = IAC;
	} else {
	    *nfrontp++ = c;
	}
    }

    if (done && !count) {
	*nfrontp++ = IAC;
	*nfrontp++ = EOR;
	netflush();		/* try to move along as quickly as ... */
    }
    return(origCount - count);
}

/* DataToTerminal - queue up some data to go to terminal. */

int
DataToTerminal(buffer, count)
register char	*buffer;		/* where the data is */
register int	count;			/* how much to send */
{
    int origCount;
#if	defined(unix)
    fd_set	o;

    FD_ZERO(&o);
#endif	/* defined(unix) */
    origCount = count;

    while (count) {
	if (tfrontp >= ttyobuf+sizeof ttyobuf) {
	    ttyflush();
	    while (tfrontp >= ttyobuf+sizeof ttyobuf) {
#if	defined(unix)
		FD_SET(tout, &o);
		(void) select(tout+1, (fd_set *) 0, &o, (fd_set *) 0,
						(struct timeval *) 0);
#endif	/* defined(unix) */
		ttyflush();
	    }
	}
	*tfrontp++ = *buffer++;
	count--;
    }
    return(origCount - count);
}

/* EmptyTerminal - called to make sure that the terminal buffer is empty.
 *			Note that we consider the buffer to run all the
 *			way to the kernel (thus the select).
 */

void
EmptyTerminal()
{
#if	defined(unix)
    fd_set	o;

    FD_ZERO(&o);
#endif	/* defined(unix) */

    if (tfrontp == tbackp) {
#if	defined(unix)
	FD_SET(tout, &o);
	(void) select(tout+1, (int *) 0, &o, (int *) 0,
			(struct timeval *) 0);	/* wait for TTLOWAT */
#endif	/* defined(unix) */
    } else {
	while (tfrontp != tbackp) {
	    ttyflush();
#if	defined(unix)
	    FD_SET(tout, &o);
	    (void) select(tout+1, (int *) 0, &o, (int *) 0,
				(struct timeval *) 0);	/* wait for TTLOWAT */
#endif	/* defined(unix) */
	}
    }
}


/*
 * Push3270 - Try to send data along the 3270 output (to screen) direction.
 */

static int
Push3270()
{
    int save = scc;

    if (scc) {
	if (Ifrontp+scc > Ibuf+sizeof Ibuf) {
	    if (Ibackp != Ibuf) {
		memcpy(Ibuf, Ibackp, Ifrontp-Ibackp);
		Ifrontp -= (Ibackp-Ibuf);
		Ibackp = Ibuf;
	    }
	}
	if (Ifrontp+scc < Ibuf+sizeof Ibuf) {
	    telrcv();
	}
    }
    return save != scc;
}


/*
 * Finish3270 - get the last dregs of 3270 data out to the terminal
 *		before quitting.
 */

static void
Finish3270()
{
    while (Push3270() || !DoTerminalOutput()) {
#if	defined(unix)
	HaveInput = 0;
#endif	/* defined(unix) */
	;
    }
}


/* StringToTerminal - output a null terminated string to the terminal */

void
StringToTerminal(s)
char *s;
{
    int count;

    count = strlen(s);
    if (count) {
	(void) DataToTerminal(s, count);	/* we know it always goes... */
    }
}


#if	((!defined(NOT43)) || defined(PUTCHAR))
/* _putchar - output a single character to the terminal.  This name is so that
 *	curses(3x) can call us to send out data.
 */

void
_putchar(c)
char c;
{
    if (tfrontp >= ttyobuf+sizeof ttyobuf) {
	(void) DataToTerminal(&c, 1);
    } else {
	*tfrontp++ = c;		/* optimize if possible. */
    }
}
#endif	/* ((!defined(NOT43)) || defined(PUTCHAR)) */
#endif	/* defined(TN3270) */