/*
 * vt102.c:
 *
 * Copyright (c) 2008 James McKenzie <james@fishsoup.dhs.org>,
 * All rights reserved.
 *
 */

static char rcsid[] = "$Id$";

/*
 * $Log$
 * Revision 1.8  2008/02/06 11:49:47  james
 * *** empty log message ***
 *
 * Revision 1.7  2008/02/06 11:30:37  james
 * *** empty log message ***
 *
 * Revision 1.6  2008/02/05 01:11:46  james
 * *** empty log message ***
 *
 * Revision 1.5  2008/02/04 20:23:55  james
 * *** empty log message ***
 *
 * Revision 1.4  2008/02/04 05:45:55  james
 * ::
 *
 * Revision 1.3  2008/02/04 02:05:06  james
 * *** empty log message ***
 *
 * Revision 1.2  2008/02/04 01:32:39  james
 * *** empty log message ***
 *
 * Revision 1.1  2008/02/03 23:36:41  james
 * *** empty log message ***
 *
 */


/* Termcap he say:

vt102|dec vt102:\
        :mi:\
        :al=\E[L:dc=\E[P:dl=\E[M:ei=\E[4l:im=\E[4h:tc=vt100:

vt100|vt100-am|dec vt100 (w/advanced video):\
        :am:bs:ms:xn:xo:\
        :co#80:it#8:li#24:vt#3:\
        :DO=\E[%dB:LE=\E[%dD:RA=\E[?7l:RI=\E[%dC:SA=\E[?7h:\
        :UP=\E[%dA:\
        :ac=``aaffggjjkkllmmnnooppqqrrssttuuvvwwxxyyzz{{||}}~~:\
        :ae=^O:as=^N:bl=^G:cb=\E[1K:cd=\E[J:ce=\E[K:cl=\E[H\E[J:\
        :cm=\E[%i%d;%dH:cr=^M:cs=\E[%i%d;%dr:ct=\E[3g:do=^J:\
        :eA=\E(B\E)0:ho=\E[H:kb=^H:kd=\EOB:ke=\E[?1l\E>:kl=\EOD:\
        :kr=\EOC:ks=\E[?1h\E=:ku=\EOA:le=^H:mb=\E[5m:md=\E[1m:\
        :me=\E[m\017:mr=\E[7m:nd=\E[C:rc=\E8:\
        :rs=\E>\E[?3l\E[?4l\E[?5l\E[?7h\E[?8h:sc=\E7:se=\E[m:\
        :sf=^J:so=\E[7m:sr=\EM:st=\EH:ta=^I:ue=\E[m:up=\E[A:\
        :us=\E[4m:tc=vt100+fnkeys:

vt100+fnkeys|dec vt100 numeric keypad:\
        :k0=\EOy:k5=\EOt:k6=\EOu:k7=\EOv:k8=\EOl:k9=\EOw:k;=\EOx:\
        :tc=vt100+pfkeys:

vt100+pfkeys|dec vt100 numeric keypad:\
        :@8=\EOM:k1=\EOP:k2=\EOQ:k3=\EOR:k4=\EOS:tc=vt100+keypad:

vt100+keypad|dec vt100 numeric keypad no fkeys:\
        :K1=\EOq:K2=\EOr:K3=\EOs:K4=\EOp:K5=\EOn:

*/

/*
so the parser needs to be able to at least do
CTRL-G
CTRL-H
CTRL-I
CTRL-J
CTRL-M
CTRL-N
CTRL-O

ESC7
ESC8
ESCH
ESCM
ESC> 

ESC[%dA
ESC[%dB
ESC[%dC
ESC[%dD
ESC[H
ESC[%d;%dH
ESC[J
ESC[K
ESC[1K
ESC[L
ESC[M
ESC[P

ESC[3g
ESC[4h
ESC[4l
ESC[m 
ESC[1m
ESC[4m
ESC[5m
ESC[7m
ESC[%d;%dr

ESC(B
ESC)0

ESC[?3l 
ESC[?4l 
ESC[?5l
ESC[?7h
ESC[?7h
ESC[?7l
ESC[?8h

*/

#include "project.h"


static inline int
csi_ender (int c)
{
  if ((c >= 'a') && (c <= 'z'))
    return 1;
  if ((c >= 'A') && (c <= 'Z'))
    return 1;
  return 0;
}

static inline int
csi_starter (int c)
{
  switch (c)
    {
    case '[':
    case '(':
    case ')':
      return 1;
    }
  return 0;
}


void
vt102_cursor_normalize (VT102 * v, int do_wrapscroll, int use_margins)
{
  int wrap = do_wrapscroll ? 1 : 0;
  int scroll = do_wrapscroll ? 1 : 0;
  CRT_Pos *top, *bottom;

  if (use_margins)
    {
      top = &v->top_margin;
      bottom = &v->bottom_margin;
    }
  else
    {
      top = &v->screen_start;
      bottom = &v->screen_end;
    }

  if (v->pos.x < top->x)        /*don't wrap backwards */
    v->pos.x = top->x;

  if (v->pos.x > bottom->x)
    {
      if (wrap)
        {
          v->pos.x = top->x;
          v->pos.y++;
        }
      else
        {
          v->pos.x = bottom->x;
        }
    }

  if (v->pos.y < top->y)
    v->pos.y = top->y;

  if (v->pos.y > bottom->y)
    {
      if (scroll)
        crt_scroll_up (&v->crt, *top, *bottom, 1);
      v->pos.y = bottom->y;
    }
}


void
vt102_cursor_motion (VT102 * v, int x, int y, int wrapscroll)
{
  while (x > 0)
    {
      x--;
      v->pos.x++;
      vt102_cursor_normalize (v, wrapscroll, 1);
    }

  while (x < 0)
    {
      x++;
      v->pos.x--;
      vt102_cursor_normalize (v, wrapscroll, 1);
    }

  while (y > 0)
    {
      y--;
      v->pos.y++;
      vt102_cursor_normalize (v, wrapscroll, 1);
    }

  while (y < 0)
    {
      y++;
      v->pos.y--;
      vt102_cursor_normalize (v, wrapscroll, 1);
    }
}

void
vt102_delete_from_line (VT102 * v, CRT_Pos p)
{
  int n = v->bottom_margin.x - p.x;

  if (n < 0)
    return;

  if (n)
    {

      memmove (&v->crt.screen[CRT_ADDR_POS (&p)],
               &v->crt.screen[CRT_ADDR_POS (&p) + 1], sizeof (CRT_CA) * n);
    }

  v->crt.screen[CRT_ADDR (p.y, v->bottom_margin.x)].chr = ' ';
/*But not attr due to vt102 bug*/
}

void
vt102_insert_into_line (VT102 * v, CRT_Pos p)
{
  int n = v->bottom_margin.x - p.x;

  if (n < 0)
    return;

  if (n)
    {

      memmove (&v->crt.screen[CRT_ADDR_POS (&p) + 1],
               &v->crt.screen[CRT_ADDR_POS (&p) ], sizeof (CRT_CA) * n);
    }

  v->crt.screen[CRT_ADDR (p.y, v->bottom_margin.x)].chr = ' ';
  v->crt.screen[CRT_ADDR (p.y, v->bottom_margin.x)].attr = CRT_ATTR_NORMAL;
}

void
vt102_change_mode (VT102 * v, int private, char *ns, int set)
{
  int m;


  if (*ns)
    {
      m = atoi (ns);
    }
  else
    {
      m = 1;
    }

  if (m < 0)
    return;
  if (m >= VT102_NMODES)
    return;

  if (private)
    v->private_modes[m] = set;
  else
    v->modes[m] = set;

  fprintf (stderr, "mode set=%d private=%d num=%d\n", set, private, m);
}

void
vt102_parse_mode_string (VT102 * v, char *buf, int len)
{
  int private = 0;
  char last = buf[len - 1];
  char num[4];
  int o;

  memset (num, 0, sizeof (num));
  o = sizeof (num) - 1;

  len--;

  if (*buf == '?')
    {
      private++;
      buf++;
      len--;
    }

  if (len < 0)
    return;

  while (len--)
    {
      if (*buf == ';')
        {
          vt102_change_mode (v, private, &num[o], last == 'h');
          memset (num, 0, sizeof (num));
          o = sizeof (num) - 1;
          buf++;
          continue;
        }

      num[0] = num[1];
      num[1] = num[2];
      num[2] = *buf;

      if (o)
        o--;

      buf++;
    }

  vt102_change_mode (v, private, &num[o], last == 'h');

}

void
vt102_parse_esc (VT102 * v, int c)
{
  fprintf (stderr, "ESC 0%o(%c)\n", c, c);
}

void
vt102_parse_csi (VT102 * v, char *buf, int len)
{
  char last;
  char *ptr;
  char *arg = buf + 1;
  int narg;

  buf[len] = 0;

  last = buf[len - 1];
#if 0
  buf[len - 1] = 0;
#endif

  if (len > 2)
    {
      narg = atoi (arg);
    }
  else
    {
      narg = 1;
    }

  switch (buf[0])
    {
    case '[':
      switch (last)
        {
        case 'A':
          vt102_cursor_motion (v, 0, -narg, 0);
          break;
        case 'B':
          vt102_cursor_motion (v, 0, narg, 0);
          break;
        case 'C':
          vt102_cursor_motion (v, narg, 0, 0);
          break;
        case 'D':
          vt102_cursor_motion (v, -narg, 0, 0);
          break;
        case 'H':
          v->pos.y = narg - 1;

          ptr = index (arg, ';');
          if (ptr)
            v->pos.x = atoi (ptr + 1) - 1;
          else
            v->pos.x = 0;

          vt102_cursor_normalize (v, 0, 0);
          break;
        case 'J':
          fprintf (stderr, "OCTOPUS %d\n", narg);
          switch (narg)
            {
            case 1:
              crt_erase (&v->crt, v->pos, v->screen_end, 1);
              break;
            case 2:
              crt_erase (&v->crt, v->screen_start, v->screen_end, 1);
              break;
            }
          break;
        case 'K':
          {
            CRT_Pos ls = { 0, v->pos.y };
            CRT_Pos le = { VT102_COLS - 1, v->pos.y };
            if (len == 2)
              narg = 0;         /*Different default */

            switch (narg)
              {
              case 0:
                fprintf (stderr, "FISH %d %d -> %d %d\n",
                         v->pos.x, v->pos.y, le.x, le.y);
                crt_erase (&v->crt, v->pos, le, 1);
                break;
              case 1:
                fprintf (stderr, "SOUP %d %d -> %d %d\n",
                         ls.x, ls.y, v->pos.x, v->pos.y);
                crt_erase (&v->crt, ls, v->pos, 1);
                break;
              case 2:
                fprintf (stderr, "TREE %d %d -> %d %d\n",
                         ls.x, ls.y, le.x, le.y);
                crt_erase (&v->crt, ls, le, 1);
                break;
              }
          }
          break;

        case 'P':
          while (narg--)
            vt102_delete_from_line (v, v->pos);
          break;
        case 'L':
          if ((v->pos.y >= v->top_margin.y)
              && (v->pos.y <= v->bottom_margin.y))
            {
              while (narg--)
                crt_scroll_down (&v->crt, v->pos, v->bottom_margin, 1);
            }
          break;

        case 'M':
          if ((v->pos.y >= v->top_margin.y)
              && (v->pos.y <= v->bottom_margin.y))
            {
              while (narg--)
                crt_scroll_up (&v->crt, v->pos, v->bottom_margin, 0);
            }
          break;

        case 'g':
          fprintf (stderr, "C: CSI %s buf[0]=%c\n", buf, buf[0]);
          break;

        case 'h':
        case 'l':
          fprintf (stderr, "D: CSI %s buf[0]=%c\n", buf, buf[0]);
          vt102_parse_mode_string (v, &buf[1], len - 1);
          break;

        case 'm':
          //horror of horrors parsing the ;
          break;
        case 'r':
          v->top_margin = v->screen_start;
          v->bottom_margin = v->screen_end;

          if ((len > 2) && (ptr = index (arg, ';')))
            {
              ptr++;
              v->top_margin.y = narg - 1;
              v->bottom_margin.y = atoi (ptr) - 1;
            }

          if (v->top_margin.y < v->screen_start.y)
            v->top_margin.y = v->screen_start.y;
          if (v->top_margin.y > v->screen_end.y)
            v->top_margin.y = v->screen_end.y;
          if (v->bottom_margin.y < v->screen_start.y)
            v->bottom_margin.y = v->screen_start.y;
          if (v->bottom_margin.y > v->screen_end.y)
            v->bottom_margin.y = v->screen_end.y;

          fprintf (stderr, "D: %d %d\n", v->top_margin.y, v->bottom_margin.y);

          v->pos = v->top_margin;
          break;

        default:
          fprintf (stderr, "A: CSI %s buf[0]=%c\n", buf, buf[0]);
        }
      break;
    default:
      fprintf (stderr, "B: CSI %s buf[0]=%c\n", buf, buf[0]);
    }



}

void
vt102_status_line (VT102 * v, char *str)
{
  int i = VT102_COLS;
  CRT_CA *ca = &v->crt.screen[CRT_ADDR (VT102_STATUS_ROW, 0)];

  while (i--)
    {
      ca->attr = CRT_ATTR_REVERSE;
      ca->chr = *str;
      if (*str)
        str++;
      ca++;
    }

}


void
vt102_parse_char (VT102 * v, int c)
{
  VT102_parser *p = &v->parser;

#if 0
  fprintf (stderr, "%c pc %d %d %d   %d %d\n", (c > 31) ? 32 : c, c,
           p->in_csi, p->in_escape, v->pos.x, v->pos.y);
#endif
  if (p->in_csi)
    {
      p->csi_buf[p->csi_ptr++] = c;
      if (csi_ender (c) || (p->csi_ptr == VT102_CSI_LEN))
        {
          vt102_parse_csi (v, p->csi_buf, p->csi_ptr);
          p->in_csi = 0;
        }
    }
  else if (p->in_escape)
    {
      if (csi_starter (c))
        {
          p->csi_ptr = 0;
          p->csi_buf[p->csi_ptr++] = c;
          p->in_csi++;
          p->in_escape = 0;
        }
      else
        {
          p->in_escape = 0;
          vt102_parse_esc (v, c);
        }
    }
  else
    {

      switch (c)
        {
         /*NUL*/ case 0:
         /*SOH*/ case 1:
         /*STX*/ case 2:
         /*ETX*/ case 3:
         /*EOT*/ case 4:
         /*ENQ*/ case 5:
         /*ACK*/ case 6:
         /*BEL*/ case 7:
          break;
         /*BS*/ case 8:
          vt102_cursor_motion (v, -1, 0, 1);
          break;
         /*HT*/ case 9:
          v->pos.x += 8;
          v->pos.x &= ~7;
          vt102_cursor_normalize (v, 1, 1);
          break;
         /*LF*/ case 10:
         /*VT*/ case 11:
         /*FF*/ case 12:
          vt102_cursor_motion (v, 0, 1, 1);
	  if (v->modes[VT102_MODE_NEWLINE_MODE]) 
          	v->pos.x = v->top_margin.x;
          break;
         /*CR*/ case 13:
          v->pos.x = v->top_margin.x;
          break;
         /*SO*/ case 14:
         /*SI*/ case 15:
         /*DLE*/ case 16:
        /*DC1 */ case 17:
        /*DC2 */ case 18:
        /*DC3 */ case 19:
        /*DC4 */ case 20:
         /*NAK*/ case 21:
         /*SYN*/ case 22:
         /*ETB*/ case 23:
         /*CAN*/ case 24:
         /*EM*/ case 25:
         /*SUB*/ case 26:
          break;
         /*ESC*/ case 27:
          p->in_escape++;
          return;
         /*FS*/ case 28:
         /*GS*/ case 29:
         /*RS*/ case 30:
         /*US*/ case 31:
         /*DEL*/ case 127:
          break;
        /*regular character */ default:

	  if (v->modes[VT102_MODE_INSERT]) 
		vt102_insert_into_line(v,v->pos);

          v->crt.screen[CRT_ADDR_POS (&v->pos)].chr = c;
          v->crt.screen[CRT_ADDR_POS (&v->pos)].attr = v->attr;
          vt102_cursor_motion (v, 1, 0, 1);
        }
    }

  v->crt.pos = v->pos;

  vt102_status_line (v, "VT102 foo bar baz I'm the urban spaceman baby");
}

void
vt102_parser_reset (VT102_parser * p)
{
  p->in_csi = 0;
  p->in_escape = 0;
  p->csi_ptr = 0;
}

void
vt102_reset (VT102 * v)
{
  VT102_parser *p = &v->parser;

  vt102_parser_reset (p);
  crt_cls (&v->crt);


  v->screen_start.x = 0;
  v->screen_start.y = 0;
  v->screen_end.x = VT102_COLS - 1;
  v->screen_end.y = VT102_ROWS - 1;

  v->top_margin = v->screen_start;
  v->bottom_margin = v->screen_end;

  v->pos = v->screen_start;

  memset(v->modes,0,VT102_NMODES);
  memset(v->private_modes,0,VT102_NMODES);

  v->modes[VT102_PRIVATE_MODE_AUTO_WRAP]=1;
  v->modes[VT102_PRIVATE_MODE_AUTO_REPEAT]=1;


}