/* pdp18b_g2tty.c: PDP-7/9 Bell Labs "GRAPHIC-2" subsystem (as a TTY!!)
   from 13-Sep-15 version of pdp18b_tt1.c

   Copyright (c) 1993-2015, Robert M Supnik
   Copyright (c) 2016, Philip L Budne

   Permission is hereby granted, free of charge, to any person obtaining a
   copy of this software and associated documentation files (the "Software"),
   to deal in the Software without restriction, including without limitation
   the rights to use, copy, modify, merge, publish, distribute, sublicense,
   and/or sell copies of the Software, and to permit persons to whom the
   Software is furnished to do so, subject to the following conditions:

   The above copyright notice and this permission notice shall be included in
   all copies or substantial portions of the Software.

   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
   ROBERT M SUPNIK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
   IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

   Except as contained in this notice, the name of Robert M Supnik shall not be
   used in advertising or otherwise to promote the sale, use or other dealings
   in this Software without prior written authorization from Robert M Supnik.

   Doug McIlroy had this to say about the Bell Labs PDP-7 Ken Thompson
   created UNIX on:

      The pdp7 was cast off by the visual and acoustics research department.
      Bill Ninke et al. built graphic II on it -- a graphics attachment as big
      as the pdp7 itself. The disk was an amazing thing about 2' in diameter,
      mounted on a horizontal axis. Mystery crashes bedeviled it until somebody
      realized that the axis was perpendicular to the loading dock 4 floors
      below. A 90-degree turn solved the problem.

   The graphics system responds as ten PDP-7 "devices";
   UNIX only uses six, and only three of the six are simulated here
   (and *JUST* enough of those to figure out the text being displayed),
   as two SIMH DEVICES, G2OUT and G2IN:

   G2OUT:
       G2D1     005     GRAPHICS-2 display output
   G2IN:
       G2KB     043     GRAPHICS-2 keyboard
       G2BB     044     GRAPHICS-2 button box (lighted bush buttons)

   19-Mar-16    PLB     Working (up to a screen full)
   17-Mar-16    PLB     Cloned from 13-Sep-15 version of pdp18b_tt1.c
*/

#include "pdp18b_defs.h"
#ifdef GRAPHICS2
#include "sim_tmxr.h"
#include <ctype.h>

uint8 g2kb_done = 0;                    /* keyboard flag */
uint32 g2kb_buf = 0;                    /* keyboard buffer */

uint8 g2bb_flag = 0;                    /* button flag */
uint32 g2bb_bbuf = 0;                   /* button buffer */
uint32 g2bb_lbuf = 0;                   /* button lights buffer */

uint32 g2out_addr = 0;                  /* display address */
int32 g2out_count = 0;                  /* character count (not a hw reg) */
uint8 g2out_stuffcr = 0;                /* need to stuff a CR */

/* terminal mux data */
TMLN g2_ldsc = { 0 };                   /* line descriptor */
TMXR g2_desc = { 1, 0, 0, &g2_ldsc };   /* mux descriptor */

/* kernel display lists always start like this: */
static const int32 g2_expect[3] = {
    0065057, /* PARAM: clear blink, clear light pen, scale=1, intensity=3 */
    0147740, /* X-Y: invisible, no delay, Y=01740 (992) */
    0160000  /* X-Y: invisible, settling delay, X=0 */
};

extern int32 *M;
extern int32 int_hwre[API_HLVL+1];
extern int32 api_vec[API_HLVL][32];
extern int32 tmxr_poll;
extern int32 stop_inst;

/* SIMH G2IN DEVICE */
t_bool g2kb_test_done ();
void g2kb_set_done ();
void g2kb_clr_done ();
int32 g2kb_iot (int32 dev, int32 pulse, int32 dat); /* device 043 */

t_bool g2bb_test_flag ();
void g2bb_set_flag ();
void g2bb_clr_flag ();
int32 g2bb_iot (int32 dev, int32 pulse, int32 dat); /* device 044 */

t_stat g2in_svc (UNIT *uptr);

/* SIMH G2OUT DEVICE */
int32 g2d1_iot (int32 dev, int32 pulse, int32 dat); /* device 05 */

/* both G2IN/G2OUT: */
t_stat g2_attach (UNIT *uptr, char *cptr);
t_stat g2_detach (UNIT *uptr);
t_stat g2_reset (DEVICE *dptr);

/****************************************************************
 * SIMH G2IN (keyboard/buttons) DEVICE data structures
 *
 *  g2in_dev     G2IN device descriptor
 *  g2in_unit    G2IN unit descriptor
 *  g2in_reg     G2IN register list
 *  g2in_mod     G2IN modifiers list
 */

DIB g2in_dib = { DEV_G2KB, 2, NULL, { &g2kb_iot, &g2bb_iot } };

UNIT g2in_unit = {
    UDATA (&g2in_svc, UNIT_IDLE|UNIT_ATTABLE, 0), KBD_POLL_WAIT
};

REG g2in_reg[] = {
    { ORDATA (KBBUF, g2kb_buf, 1) },
    { ORDATA (KBDONE, g2kb_done, 1) },
    { FLDATA (INT, int_hwre[API_G2], INT_V_G2) },
    { DRDATA (TIME, g2in_unit.wait, 24), REG_NZ + PV_LEFT },
    { ORDATA (BBBBUF, g2bb_bbuf, 1) },  /* button box button buffer */
    { ORDATA (BBFLAG, g2bb_flag, 1) },  /* button box IRQ */
    { ORDATA (BBLBUF, g2bb_lbuf, 1) },  /* button box lights buffer */
    { NULL }
    };

MTAB g2in_mod[] = {
    { UNIT_ATT, UNIT_ATT, "summary", NULL,
      NULL, &tmxr_show_summ, (void *) &g2_desc },
    { MTAB_XTD | MTAB_VDV, 1, NULL, "DISCONNECT",
      &tmxr_dscln, NULL, (void *) &g2_desc },
    { MTAB_XTD | MTAB_VDV | MTAB_NMO, 1, "CONNECTIONS", NULL,
      NULL, &tmxr_show_cstat, (void *) &g2_desc },
    { MTAB_XTD | MTAB_VDV | MTAB_NMO, 0, "STATISTICS", NULL,
      NULL, &tmxr_show_cstat, (void *) &g2_desc },
    { MTAB_XTD|MTAB_VUN|MTAB_NC, 0, "LOG", "LOG",
      &tmxr_set_log, &tmxr_show_log, &g2_desc },
    { MTAB_XTD|MTAB_VUN|MTAB_NC, 0, NULL, "NOLOG",
      &tmxr_set_nolog, NULL, &g2_desc },
    { MTAB_XTD|MTAB_VDV, 0, "DEVNO", "DEVNO",
      NULL, &show_devno, NULL },
    { 0 }
    };

/* SIMH G2IN device descriptor (GRAPHICS-2 keyboard & button box) */
DEVICE g2in_dev = {
    "G2IN",                             /* name */
    &g2in_unit,                         /* units */
    g2in_reg, g2in_mod,                 /* registers, modifiers */
    1,                                  /* numunits */
    10, 31,                             /* aradix, awidth */
    1, 8, 8,                            /* aincr, dradix, dwidth */
    &tmxr_ex, &tmxr_dep, &g2_reset,     /* examine, deposit, reset */
    NULL, &g2_attach, &g2_detach,       /* boot, attach, detach */
    &g2in_dib, DEV_MUX | DEV_DISABLE    /* ctxt, flags */
    };

/****************************************************************
 * SIMH G2OUT (display output) DEVICE data structures
 * Only needed to hold "iot" routine, since DIB's can't represent
 * devices with register sets as sparse as GRAPHICS-2
 *
 *  g2out_dev     G2OUT device descriptor
 *  g2out_unit    G2OUT unit descriptor
 *  g2out_reg     G2OUT register list
 *  g2out_mod     G2OUT modifiers list
 */

DIB g2out_dib = { DEV_G2D1, 1, NULL, { &g2d1_iot } };

UNIT g2out_unit = { UDATA (NULL, 0, 0) };

REG g2out_reg[] = {
    { ORDATA (DPYADDR, g2out_addr, 1) },
    { NULL }
    };

MTAB g2out_mod[] = {
    { MTAB_XTD|MTAB_VUN, 0, NULL, "DISCONNECT",
      &tmxr_dscln, NULL, &g2_desc },
    { MTAB_XTD|MTAB_VDV, 0, "DEVNO", "DEVNO",
      NULL, &show_devno, NULL },
    { 0 }
    };

/* SIMH G2OUT device descriptor (simulates just one of many display IOTs!) */
DEVICE g2out_dev = {
    "G2OUT",                            /* name */
    &g2out_unit,                        /* units */
    g2out_reg, g2out_mod,               /* registers, modifiers */
    1,                                  /* numunits */
    10, 31,                             /* aradix, awidth */
    1, 8, 8,                            /* aincr, dradix, dwidth */
    NULL, NULL, &g2_reset,              /* examine, deposit, reset */
    NULL, NULL, NULL,                   /* boot, attach, detach */
    &g2out_dib, DEV_DISABLE             /* ctxt, flags */
    };

/****************************************************************
 * IOT routines
 */

/* Keyboard input IOT routine */
/* real device could have done bitwise decode?! */
int32 g2kb_iot (int32 dev, int32 pulse, int32 dat)
{
if (pulse == 001) {                     /* sck */
    if (g2kb_done) {
        dat = dat | IOT_SKP;
        }
    }
else if (pulse == 002) {                /* lck */
    dat = dat | g2kb_buf;               /* return buffer */
    }
else if (pulse == 004) {                /* cck */
    g2kb_clr_done ();                   /* clear flag */
    }
return dat;
}

/* Button Box IOT routine */
/* real device could have done bitwise decode? */
int32 g2bb_iot (int32 dev, int32 pulse, int32 dat)
{
if (pulse == 001) {                     /* "spb" -- skip on push button flag */
    if (g2bb_flag)
        dat = dat | IOT_SKP;
    }
else if (pulse == 002)                  /* "lpb" -- load push buttons */
    dat = dat | g2bb_bbuf;              /* return buttons */
else if (pulse == 004)                  /* "cpb" -- clear push button flag */
    g2bb_clr_flag ();                   /* clear flag */
else if (pulse == 020) {                /* "wbl" -- write buttons lights */
    g2bb_lbuf = dat;
    }
return dat;
}

/* Input side Unit service */
t_stat g2in_svc (UNIT *uptr)
{
int32 ln, c;

if ((uptr->flags & UNIT_ATT) == 0)              /* attached? */
    return SCPE_OK;
if (g2bb_lbuf & 02000) {                        /* button 7 lit? */
    g2bb_bbuf |= 02000;                         /* press it to clear screen! */
    g2bb_set_flag ();
    }
sim_clock_coschedule (uptr, tmxr_poll);         /* continue poll */
ln = tmxr_poll_conn (&g2_desc);                 /* look for connect */
if (ln >= 0)                                    /* got one? rcv enab */
    g2_ldsc.rcve = 1;
tmxr_poll_rx (&g2_desc);                        /* poll for input */
if (g2_ldsc.conn) {                             /* connected? */
    tmxr_poll_tx (&g2_desc);                    /* PLB: poll xmt */
    if ((c = tmxr_getc_ln (&g2_ldsc))) {        /* get char */
        if (c & SCPE_BREAK)                     /* break? */
            c = 0;
        else {
            c &= 0177;
            if (c == '\r')                      /* translate CR but not ESC! */
                c = '\n';
            }
        g2kb_buf = c;
        g2kb_set_done ();
        }
    } /* connected */
else {
    /* not connected; next connection sees entire "screen" */
    g2out_count = 0;
    g2out_stuffcr = 0;
    }
return SCPE_OK;
}

/* Interrupt handling routines */

t_bool g2kb_test_done ()
{
return g2kb_done != 0;
}

void g2kb_set_done ()
{
g2kb_done = 1;
SET_INT (G2);
return;
}

void g2kb_clr_done ()
{
g2kb_done = 0;
CLR_INT (G2);
return;
}

t_bool g2bb_test_flag ()
{
return g2bb_flag != 0;
}

void g2bb_set_flag ()
{
g2bb_flag = 1;
SET_INT (G2);
return;
}

void g2bb_clr_flag ()
{
g2bb_flag = 0;
CLR_INT (G2);
return;
}

/****************************************************************
 * SIMH G2OUT (Display Output) DEVICE routines
 */

/* helper to put 7-bit display character:
 * characters are only consumed if TELNET user connected & output ready/enabled
 */
static void g2out_putchar(char c)
{
if (g2_ldsc.conn && g2_ldsc.xmte) {     /* connected, tx enabled? */

    if (g2out_stuffcr) {                /* need to stuff a CR? */
        tmxr_putc_ln (&g2_ldsc, '\r');
        g2out_stuffcr = 0;
        if (!g2_ldsc.xmte)              /* full? */
            return;                     /* yes: wait until next time */
        }

    tmxr_putc_ln (&g2_ldsc, c);
    g2out_count++;                      /* consumed */

    if (c == '\n') {                    /* was it a NL? */
        if (g2_ldsc.xmte)               /* transmitter enabled? */
            tmxr_putc_ln (&g2_ldsc, '\r'); /* send CR now */
        else
            g2out_stuffcr = 1;          /* wait until next time */
        }
}
}

/* Device 05 IOT routine */
int32 g2d1_iot (int32 dev, int32 pulse, int32 dat)
{
/*
 * UNIX text display command lists always end with a TRAP
 * and display output is restarted periodicly in timer PI service code
 */
if (g2_ldsc.conn && g2_ldsc.xmte && pulse == 047) { /* conn&ready, "beg" */
    int32 n = g2out_count, i;
    g2out_addr = dat & 017777;
    for (i = g2out_addr; i < 020000; i++) {
        uint32 w = M[i] & 0777777;
        int offset = i - g2out_addr;
        if (w & 0400000)                /* TRAP (stops display engine)? */
            break;
        /* check first three words for expected setup commands */
        if (offset < sizeof(g2_expect)/sizeof(g2_expect[0])) {
            if (w != g2_expect[offset]) {
                /* TEMP: */
                printf("G2: unexpected command at %#o: %#o expected %#o\r\n",
                       i, w, g2_expect[offset]);
                break;
            }
            continue;
        }
        if (w & 0300000)        { /* not characters? */
            printf("G2: unexpected command at %#o: %#o\r\n", i, w); /* TEMP */
            break;
        }
        if (--n < 0)                    /* new? */
            g2out_putchar( (w>>7) & 0177 );

        if ((w & 0177) && --n < 0)      /* char2 & new? */
            g2out_putchar( w & 0177 );

        } /* for loop */
    if (n > 0)
        g2out_count = 0;        /* didn't see as much as last time? */
    } /* beg IOT */
return dat;
}

/****************************************************************
 * subsystem common routines (used by both G2IN and G2OUT SIMH DEVICEs)
 */

/* Reset routine */
t_stat g2_reset (DEVICE *dptr)
{
if (dptr->flags & DEV_DIS) {                            /* sync enables */
    g2in_dev.flags = g2in_dev.flags | DEV_DIS;
    g2out_dev.flags = g2out_dev.flags | DEV_DIS;
    }
else {
    g2in_dev.flags = g2in_dev.flags & ~DEV_DIS;
    g2out_dev.flags = g2out_dev.flags & ~DEV_DIS;
    }
if (g2in_unit.flags & UNIT_ATT)                         /* if attached, */
    sim_activate (&g2in_unit, tmxr_poll);               /* activate */
else sim_cancel (&g2in_unit);                           /* else stop */

g2kb_buf = 0;                                           /* clear buf */
g2kb_clr_done ();                                       /* clear done */

g2bb_bbuf = 0;                                          /* clear buttons */
g2bb_lbuf = 0;                                          /* clear lights */
g2bb_clr_flag ();

g2out_addr = 0;
g2out_count = 0;
g2out_stuffcr = 0;
sim_cancel (&g2out_unit);                                /* stop poll */
return SCPE_OK;
}

/* Attach master unit */
t_stat g2_attach (UNIT *uptr, char *cptr)
{
t_stat r;

r = tmxr_attach (&g2_desc, uptr, cptr); /* attach */
if (r != SCPE_OK)                       /* error */
    return r;
sim_activate (uptr, 0);                 /* start poll at once */
return SCPE_OK;
}

/* Detach master unit */

t_stat g2_detach (UNIT *uptr)
{
t_stat r = tmxr_detach (&g2_desc, uptr); /* detach */
sim_cancel (uptr);                       /* stop poll */
g2_ldsc.rcve = 0;
return r;
}
#endif