/*
 * utf8.c:
 *
 * Copyright (c) 2008 James McKenzie <james@fishsoup.dhs.org>,
 * All rights reserved.
 *
 */

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

/*
 * $Log$
 * Revision 1.4  2008/02/23 13:05:58  staffcvs
 * *** empty log message ***
 *
 * Revision 1.3  2008/02/23 11:48:37  james
 * *** empty log message ***
 *
 * Revision 1.2  2008/02/22 23:39:27  james
 * *** empty log message ***
 *
 * Revision 1.1  2008/02/22 19:12:05  james
 * *** empty log message ***
 *
 */

#include "project.h"


void
utf8_flush (Context * c)
{
  UTF8 *u = c->u;
  int i;

  switch (u->utf_ptr)
    {
    case 1:
      log_f (c->l, "<invalid utf-8 sequence: \\%03o>", u->utf_buf[0]);
      break;
    case 2:
      log_f (c->l, "<invalid utf-8 sequence: \\%03o \\%03o>",
             u->utf_buf[0], u->utf_buf[1]);
      break;
    case 3:
      log_f (c->l, "<invalid utf-8 sequence: \\%03o \\%03o \\%03o>",
             u->utf_buf[0], u->utf_buf[1], u->utf_buf[2]);
      break;
    case 4:
      log_f (c->l,
             "<invalid utf-8 sequence: \\%03o \\%03o \\%03o \\%03o>",
             u->utf_buf[0], u->utf_buf[1], u->utf_buf[2], u->utf_buf[3]);
      break;
    }

  for (i = 0; i < u->utf_ptr; ++i)
    vt102_parse_char (c, u->utf_buf[i]);

  u->utf_ptr = 0;
  u->in_utf8 = 0;
}

void
utf8_parse (Context * c, int ch)
{
  UTF8 *u = c->u;

  if (ch == SYM_CHAR_RESET)
    {
      u->in_utf8 = 0;
      vt102_parse_char (c, ch);
      return;
    }

  if (!u->in_utf8)
    {
      /*FIXME: for the moment we bodge utf8 support */
      if (ch == 0xb9)
        {                       /*CSI, not a valid utf8 start char */
          vt102_parse_char (c, ch);
        }
      else if ((ch & 0xe0) == 0xc0)
        {                       /*Start of two byte unicode sequence */
          u->in_utf8 = 1;
          u->utf_ptr = 0;
          u->utf_buf[u->utf_ptr++] = ch;
          u->ch = (ch & 0x1f) << 6;
          u->sh = 0;
        }
      else if ((ch & 0xf0) == 0xe0)
        {                       /*Start of three byte unicode sequence */
          u->in_utf8 = 2;
          u->utf_ptr = 0;
          u->utf_buf[u->utf_ptr++] = ch;
          u->ch = (ch & 0x0f) << 12;
          u->sh = 6;
        }
      else if ((ch & 0xf8) == 0xf0)
        {
          u->in_utf8 = 3;
          u->utf_ptr = 0;
          u->utf_buf[u->utf_ptr++] = ch;
          u->ch = (ch & 0x07) << 18;
          u->sh = 12;
        }
      else
        {
          vt102_parse_char (c, ch);
        }
    }
  else
    {
      if ((ch & 0xc0) != 0x80)
        {
          utf8_flush (c);
          vt102_parse_char (c, ch);
        }
      else
        {
          u->utf_buf[u->utf_ptr++] = ch;
          u->ch |= (ch & 0x3f) << u->sh;
          u->sh -= 6;
          u->in_utf8--;

          if (!u->in_utf8)
            vt102_parse_char (c, ch);
        }
    }
}



UTF8 *
utf8_new (void)
{
  UTF8 *ret;

  ret = (UTF8 *) malloc (sizeof (UTF8));

  ret->in_utf8 = 0;

}