/*	SCCS Id: @(#)vmstty.c	3.4	2003/09/18	*/
/* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
/* NetHack may be freely redistributed.  See license for details. */
/* tty.c - (VMS) version */

#define NEED_VARARGS
#include "hack.h"
#include "wintty.h"
#include "tcap.h"

#include <descrip.h>
#include <iodef.h>
#ifndef __GNUC__
#include <smgdef.h>
#include <ttdef.h>
#include <tt2def.h>
#else	/* values needed from missing include files */
# define SMG$K_TRM_UP	 274
# define SMG$K_TRM_DOWN  275
# define SMG$K_TRM_LEFT  276
# define SMG$K_TRM_RIGHT 277
# define TT$M_MECHTAB	  0x00000100	/* hardware tab support */
# define TT$M_MECHFORM	  0x00080000	/* hardware form-feed support */
# define TT$M_NOBRDCST	  0x00020000	/* disable broadcast messages, but  */
# define TT2$M_BRDCSTMBX  0x00000010	/* catch them in associated mailbox */
# define TT2$M_APP_KEYPAD 0x00800000	/* application vs numeric keypad mode */
#endif /* __GNUC__ */
#ifdef USE_QIO_INPUT
#include <ssdef.h>
#endif
#include <errno.h>
#include <signal.h>

unsigned long lib$disable_ctrl(), lib$enable_ctrl();
unsigned long sys$assign(), sys$dassgn(), sys$qiow();
#ifndef USE_QIO_INPUT
unsigned long smg$create_virtual_keyboard(), smg$delete_virtual_keyboard(),
	      smg$read_keystroke(), smg$cancel_input();
#else
static short FDECL(parse_function_key, (int));
#endif
static void NDECL(setctty);
static void NDECL(resettty);

#define vms_ok(sts) ((sts)&1)
#define META(c)  ((c)|0x80)	/* 8th bit */
#define CTRL(c)  ((c)&0x1F)
#define CMASK(c) (1<<CTRL(c))
#define LIB$M_CLI_CTRLT CMASK('T')	/* 0x00100000 */
#define LIB$M_CLI_CTRLY CMASK('Y')	/* 0x02000000 */
#define ESC '\033'
#define CSI META(ESC)		/* '\233' */
#define SS3 META(CTRL('O'))	/* '\217' */

extern short ospeed;
char erase_char, intr_char, kill_char;
static boolean settty_needed = FALSE,  bombing = FALSE;
static unsigned long kb = 0;
#ifdef USE_QIO_INPUT
static char inputbuf[15+1], *inp = 0;
static int  inc = 0;
#endif

#define QIO_FUNC	IO$_TTYREADALL|IO$M_NOECHO|IO$M_TRMNOECHO
#ifdef MAIL
#define TT_SPECIAL_HANDLING  (TT$M_MECHTAB|TT$M_MECHFORM|TT$M_NOBRDCST)
#define TT2_SPECIAL_HANDLING (TT2$M_BRDCSTMBX)
#else
#define TT_SPECIAL_HANDLING  (TT$M_MECHTAB|TT$M_MECHFORM)
#define TT2_SPECIAL_HANDLING (0)
#endif
#define Uword unsigned short
#define Ubyte unsigned char
struct _rd_iosb {		/* i/o status block for read */
	Uword	status,  trm_offset;
	Uword	terminator,  trm_siz;
};
struct _wr_iosb {		/* i/o status block for write */
	Uword	status,  byte_cnt;
	unsigned   : 32;
};
struct _sm_iosb {		/* i/o status block for sense-mode qio */
	Uword	  status;
	Ubyte	  xmt_speed,  rcv_speed;
	Ubyte	  cr_fill,  lf_fill,  parity;
	unsigned   : 8;
};
struct _sm_bufr {		/* sense-mode characteristics buffer */
	Ubyte	  class,  type;		/* class==DC$_TERM, type==(various) */
	Uword	  buf_siz;		/* aka page width */
#define page_width buf_siz		/* number of columns */
	      unsigned  tt_char	: 24;	/* primary characteristics */
	      unsigned  page_length	:  8;	/* number of lines */
	      unsigned  tt2_char	: 32;	/* secondary characteristics */
};
static struct {
    struct _sm_iosb io;
    struct _sm_bufr sm;
} sg = {{0},{0}};
static unsigned short tt_chan = 0;
static unsigned long  tt_char_restore = 0, tt_char_active = 0,
		      tt2_char_restore = 0, tt2_char_active = 0;
static unsigned long  ctrl_mask = 0;

int
vms_getchar()
{
    short key;
#ifdef USE_QIO_INPUT
    struct _rd_iosb iosb;
    unsigned long sts;
    unsigned char kb_buf;
#else	/* SMG input */
    static volatile int recurse = 0;	/* SMG is not AST re-entrant! */
#endif

    if (program_state.done_hup) {
	/* hangup has occurred; do not attempt to get further user input */
	return ESC;
    }

#ifdef USE_QIO_INPUT
    if (inc > 0) {
	/* we have buffered character(s) from previous read */
	kb_buf = *inp++;
	--inc;
	sts = SS$_NORMAL;
    } else {
	sts = sys$qiow(0, tt_chan, QIO_FUNC, &iosb, (void(*)())0, 0,
		       &kb_buf, sizeof kb_buf, 0, 0, 0, 0);
    }
    if (vms_ok(sts)) {
	if (kb_buf == CTRL('C')) {
	    if (intr_char) gsignal(SIGINT);
	    key = (short)kb_buf;
	} else if (kb_buf == '\r') {	/* <return> */
	    key = (short)'\n';
	} else if (kb_buf == ESC || kb_buf == CSI || kb_buf == SS3) {
	    switch(parse_function_key((int)kb_buf)) {
	      case SMG$K_TRM_UP:    key = iflags.num_pad ? '8' : 'k';  break;
	      case SMG$K_TRM_DOWN:  key = iflags.num_pad ? '2' : 'j';  break;
	      case SMG$K_TRM_LEFT:  key = iflags.num_pad ? '4' : 'h';  break;
	      case SMG$K_TRM_RIGHT: key = iflags.num_pad ? '6' : 'l';  break;
	      default:		    key = ESC;	break;
	    }
	} else {
	    key = (short)kb_buf;
	}
    } else if (sts == SS$_HANGUP || iosb.status == SS$_HANGUP
	    || sts == SS$_DEVOFFLINE) {
	gsignal(SIGHUP);
	key = ESC;
    } else			/*(this should never happen)*/
	key = getchar();

#else   /*!USE_QIO_INPUT*/
    if (recurse++ == 0 && kb != 0) {
	smg$read_keystroke(&kb, &key);
	switch (key) {
	  case SMG$K_TRM_UP:	iflags.num_pad ? '8' : key = 'k';  break;
	  case SMG$K_TRM_DOWN:	iflags.num_pad ? '2' : key = 'j';  break;
	  case SMG$K_TRM_LEFT:	iflags.num_pad ? '4' : key = 'h';  break;
	  case SMG$K_TRM_RIGHT: iflags.num_pad ? '6' : key = 'l';  break;
	  case '\r':		key = '\n'; break;
	  default:		if (key > 255)	key = ESC;
				break;
	}
    } else {
	/* abnormal input--either SMG didn't initialize properly or
	   vms_getchar() has been called recursively (via SIGINT handler).
	 */
	if (kb != 0)			/* must have been a recursive call */
	    smg$cancel_input(&kb);	/*  from an interrupt handler	   */
	key = getchar();
    }
    --recurse;
#endif	/* USE_QIO_INPUT */

    return (int)key;
}

#ifdef USE_QIO_INPUT
       /*
	* We've just gotten an <escape> character.  Do a timed read to
	* get any other characters, then try to parse them as an escape
	* sequence.  This isn't perfect, since there's no guarantee
	* that a full escape sequence will be available, or even if one
	* is, it might actually by regular input from a fast typist or
	* a stalled input connection.  {For packetized environments,
	* cross plural(body_part(FINGER)) and hope for best. :-}
	*
	* This is needed to preserve compatability with SMG interface
	* for two reasons:
	*    1) retain support for arrow keys, and
	*    2) treat other VTxxx function keys as <esc> for aborting
	*	various NetHack prompts.
	* The second reason is compelling; otherwise remaining chars of
	* an escape sequence get treated as inappropriate user commands.
	*
	* SMG code values for these key sequences fall in the range of
	* 256 thru 3xx.  The assignments are not particularly intuitive.
	*/
/*=
     -- Summary of VTxxx-style keyboards and transmitted escape sequences. --
Keypad codes are prefixed by 7 bit (\033 O) or 8 bit SS3:
	keypad:  PF1 PF2 PF3 PF4       codes:	P   Q	R   S
		  7   8   9   -			w   x	y   m
		  4   5   6   .			t   u	v   n
		  1   2   3  :en-:		q   r	s  : :
		 ...0...  ,  :ter:	       ...p...	l  :M:
Arrows are prefixed by either SS3 or CSI (either 7 or 8 bit), depending on
whether the terminal is in application or numeric mode (ditto for PF keys):
	arrows: <up> <dwn> <lft> <rgt>		A   B	D   C
Additional function keys (vk201/vk401) generate CSI nn ~ (nn is 1 or 2 digits):
    vk201 keys:  F6 F7 F8 F9 F10   F11 F12 F13 F14  Help Do   F17 F18 F19 F20
   'nn' digits:  17 18 19 20 21    23  24  25  26    28  29   31  32  33  34
     alternate:  ^C		   ^[  ^H  ^J		(when in VT100 mode)
   edit keypad: <fnd> <ins> <rmv>     digits:	1   2	3
		<sel> <prv> <nxt>		4   5	6
VT52 mode:  arrows and PF keys send ESCx where x is in A-D or P-S.
=*/

static const char *arrow_or_PF = "ABCDPQRS",	/* suffix char */
		  *smg_keypad_codes = "PQRSpqrstuvwxyMmlnABDC";
	/* PF1..PF4,KP0..KP9,enter,dash,comma,dot,up-arrow,down,left,right */
	/* Ultimate return value is (index into smg_keypad_codes[] + 256). */

static short
parse_function_key(c)
register int c;
{
    struct _rd_iosb iosb;
    unsigned long sts;
    char seq_buf[15+1];		/* plenty room for escape sequence + slop */
    short result = ESC;		/* translate to <escape> by default */

    /*
     * Read whatever we can from type-ahead buffer (1 second timeout).
     * If the user typed an actual <escape> to deliberately abort
     * something, he or she should be able to tolerate the necessary
     * restriction of a negligible pause before typing anything else.
     * We might already have [at least some of] an escape sequence from a
     * previous read, particularly if user holds down the arrow keys...
     */
    if (inc > 0) strncpy(seq_buf, inp, inc);
    if (inc < (int)(sizeof seq_buf) - 1) {
	sts = sys$qiow(0, tt_chan, QIO_FUNC|IO$M_TIMED, &iosb, (void(*)())0, 0,
		       seq_buf + inc, sizeof seq_buf - 1 - inc, 1, 0, 0, 0);
	if (vms_ok(sts))  sts = iosb.status;
    } else
	sts = SS$_NORMAL;
    if (vms_ok(sts) || sts == SS$_TIMEOUT) {
	register int cnt = iosb.trm_offset + iosb.trm_siz + inc;
	register char *p = seq_buf;
	if (c == ESC)	/* check for 7-bit vt100/ANSI, or vt52 */
	    if (*p == '[' || *p == 'O') c = META(CTRL(*p++)),  cnt--;
	    else if (strchr(arrow_or_PF, *p)) c = SS3; /*CSI*/
	if (cnt > 0 && (c == SS3 || (c == CSI && strchr(arrow_or_PF, *p)))) {
	    register char *q = strchr(smg_keypad_codes, *p);
	    if (q) result = 256 + (q - smg_keypad_codes);
	    p++,  --cnt;	/* one more char consumed */
	} else if (cnt > 1 && c == CSI) {
	    static short	/* "CSI nn ~" -> F_keys[nn] */
		F_keys[35] = {	ESC,				/*(filler)*/
				311, 312, 313, 314, 315, 316,	/* E1-E6 */
				ESC, ESC, ESC, ESC,	   /*(more filler)*/
				281, 282, 283, 284, 285, ESC,	/* F1-F5 */
				286, 287, 288, 289, 290, ESC,	/* F6-F10*/
				291, 292, 293, 294, ESC,	/*F11-F14*/
				295, 296, ESC, /*<help>,<do>, aka F15,F16*/
				297, 298, 299, 300		/*F17-F20*/
		};  /* note: there are several missing nn in CSI nn ~ values */
	    int nn;  char *q;
	    *(p + cnt) = '\0';	/* terminate string */
	    q = strchr(p, '~');
	    if (q && sscanf(p, "%d~", &nn) == 1) {
		if (nn > 0 && nn < SIZE(F_keys)) result = F_keys[nn];
		cnt -= (++q - p);
		p = q;
	    }
	}
	if (cnt > 0) strncpy((inp = inputbuf), p, (inc = cnt));
	else	     inc = 0,  inp = 0;
    }
    return result;
}
#endif	/* USE_QIO_INPUT */

static void
setctty()
{
    struct _sm_iosb iosb;
    unsigned long status;

    status = sys$qiow(0, tt_chan, IO$_SETMODE, &iosb, (void(*)())0, 0,
		      &sg.sm, sizeof sg.sm, 0, 0, 0, 0);
    if (vms_ok(status))  status = iosb.status;
    if (vms_ok(status)) {
	/* try to force terminal into synch with TTDRIVER's setting */
	number_pad((sg.sm.tt2_char & TT2$M_APP_KEYPAD) ? -1 : 1);
    } else {
	raw_print("");
	errno = EVMSERR,  vaxc$errno = status;
	perror("NetHack(setctty: setmode)");
	wait_synch();
    }
}

static void
resettty()			/* atexit() routine */
{
    if (settty_needed) {
	bombing = TRUE;     /* don't clear screen; preserve traceback info */
	settty((char *)0);
    }
    (void) sys$dassgn(tt_chan),  tt_chan = 0;
}

/*
 * Get initial state of terminal, set ospeed (for termcap routines)
 * and switch off tab expansion if necessary.
 * Called by init_nhwindows() and resume_nhwindows() in wintty.c
 * (for initial startup and for returning from '!' or ^Z).
 */
void
gettty()
{
    static char dev_tty[] = "TT:";
    static $DESCRIPTOR(tty_dsc, dev_tty);
    int err = 0;
    unsigned long status, zero = 0;

    if (tt_chan == 0) {		/* do this stuff once only */
	iflags.cbreak = OFF,  iflags.echo = ON;	/* until setup is complete */
	status = sys$assign(&tty_dsc, &tt_chan, 0, 0);
	if (!vms_ok(status)) {
	    raw_print(""),  err++;
	    errno = EVMSERR,  vaxc$errno = status;
	    perror("NetHack(gettty: $assign)");
	}
	atexit(resettty);   /* register an exit handler to reset things */
    }
    status = sys$qiow(0, tt_chan, IO$_SENSEMODE, &sg.io, (void(*)())0, 0,
		      &sg.sm, sizeof sg.sm, 0, 0, 0, 0);
    if (vms_ok(status))  status = sg.io.status;
    if (!vms_ok(status)) {
	raw_print(""),  err++;
	errno = EVMSERR,  vaxc$errno = status;
	perror("NetHack(gettty: sensemode)");
    }
    ospeed = sg.io.xmt_speed;
    erase_char = '\177';	/* <rubout>, aka <delete> */
    kill_char = CTRL('U');
    intr_char = CTRL('C');
    (void) lib$enable_ctrl(&zero, &ctrl_mask);
    /* Use the systems's values for lines and columns if it has any idea. */
    if (sg.sm.page_length)
	LI = sg.sm.page_length;
    if (sg.sm.page_width)
	CO = sg.sm.page_width;
    /* suppress tab and form-feed expansion, in case termcap uses them */
    tt_char_restore  = sg.sm.tt_char;
    tt_char_active   = sg.sm.tt_char |= TT_SPECIAL_HANDLING;
    tt2_char_restore = sg.sm.tt2_char;
    tt2_char_active  = sg.sm.tt2_char |= TT2_SPECIAL_HANDLING;
#if 0		/*[ defer until setftty() ]*/
    setctty();
#endif

    if (err) wait_synch();
}

/* reset terminal to original state */
void
settty(s)
const char *s;
{
	if (!bombing) end_screen();
	if (s) raw_print(s);
	disable_broadcast_trapping();
#if 0		/* let SMG's exit handler do the cleanup (as per doc) */
/* #ifndef USE_QIO_INPUT */
	if (kb)  smg$delete_virtual_keyboard(&kb),  kb = 0;
#endif	/* 0 (!USE_QIO_INPUT) */
	if (ctrl_mask)
	    (void) lib$enable_ctrl(&ctrl_mask, 0);
	iflags.echo = ON;
	iflags.cbreak = OFF;
	/* reset original tab, form-feed, broadcast settings */
	sg.sm.tt_char  = tt_char_restore;
	sg.sm.tt2_char = tt2_char_restore;
	setctty();

	settty_needed = FALSE;
}

/* same as settty, with no clearing of the screen */
void
shuttty(s)
const char *s;
{
	bombing = TRUE;
	settty(s);
	bombing = FALSE;
}

void
setftty()
{
	unsigned long mask = LIB$M_CLI_CTRLT | LIB$M_CLI_CTRLY;

	(void) lib$disable_ctrl(&mask, 0);
	if (kb == 0) {		/* do this stuff once only */
#ifdef USE_QIO_INPUT
	    kb = tt_chan;
#else   /*!USE_QIO_INPUT*/
	    smg$create_virtual_keyboard(&kb);
#endif  /*USE_QIO_INPUT*/
	    init_broadcast_trapping();
	}
	enable_broadcast_trapping();	/* no-op if !defined(MAIL) */
	iflags.cbreak = (kb != 0) ? ON : OFF;
	iflags.echo   = (kb != 0) ? OFF : ON;
	/* disable tab & form-feed expansion; prepare for broadcast trapping */
	sg.sm.tt_char  = tt_char_active;
	sg.sm.tt2_char = tt2_char_active;
	setctty();

	start_screen();
	settty_needed = TRUE;
}

void
intron()		/* enable kbd interupts if enabled when game started */
{
	intr_char = CTRL('C');
}

void
introff()		/* disable kbd interrupts if required*/
{
	intr_char = 0;
}

#ifdef TIMED_DELAY

extern unsigned long
	FDECL(lib$emul, (const long *,const long *,const long *,long *));
extern unsigned long sys$schdwk(), sys$hiber();

#define VMS_UNITS_PER_SECOND 10000000L	/* hundreds of nanoseconds, 1e-7 */
/* constant for conversion from milliseconds to VMS delta time (negative) */
static const long mseconds_to_delta = VMS_UNITS_PER_SECOND / 1000L * -1L;

/* sleep for specified number of milliseconds (note: the timer used
   generally only has 10-millisecond resolution at the hardware level...) */
void msleep(mseconds)
unsigned mseconds;	/* milliseconds */
{
    long pid = 0L, zero = 0L, msec, qtime[2];

    msec = (long) mseconds;
    if (msec > 0 &&
	/* qtime{0:63} = msec{0:31} * mseconds_to_delta{0:31} + zero{0:31} */
	vms_ok(lib$emul(&msec, &mseconds_to_delta, &zero, qtime))) {
	/* schedule a wake-up call, then go to sleep */
	if (vms_ok(sys$schdwk(&pid, (genericptr_t)0, qtime, (long *)0)))
	    (void)sys$hiber();
    }
}

#endif	/* TIMED_DELAY */


/* fatal error */
/*VARARGS1*/
void
error VA_DECL(const char *,s)
	VA_START(s);
	VA_INIT(s, const char *);
	if(settty_needed)
		settty((char *)0);
	Vprintf(s,VA_ARGS);
	(void) putchar('\n');
	VA_END();
#ifndef SAVE_ON_FATAL_ERROR
	/* prevent vmsmain's exit handler byebye() from calling hangup() */
	(void)signal(SIGHUP, SIG_DFL);
#endif
	exit(EXIT_FAILURE);
}
