/*
 * Copyright © 2013  Google, Inc.
 *
 *  This is part of HarfBuzz, a text shaping library.
 *
 * Permission is hereby granted, without written agreement and without
 * license or royalty fees, to use, copy, modify, and distribute this
 * software and its documentation for any purpose, provided that the
 * above copyright notice and the following two paragraphs appear in
 * all copies of this software.
 *
 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 *
 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
 *
 * Google Author(s): Behdad Esfahbod
 */

#ifndef HB_BUFFER_DESERIALIZE_TEXT_HH
#define HB_BUFFER_DESERIALIZE_TEXT_HH

#include "hb-private.hh"

%%{
  machine deserialize_text;
  alphtype unsigned char;
  write data;
}%%

static hb_bool_t
parse_uint (const char *pp, const char *end, uint32_t *pv)
{
  char buf[32];
  unsigned int len = MIN (ARRAY_LENGTH (buf) - 1, (unsigned int) (end - pp));
  strncpy (buf, pp, len);
  buf[len] = '\0';

  char *p = buf;
  char *pend = p;
  uint32_t v;

  errno = 0;
  v = strtol (p, &pend, 10);
  if (errno || p == pend || pend - p != end - pp)
    return false;

  *pv = v;
  return true;
}

static hb_bool_t
parse_int (const char *pp, const char *end, int32_t *pv)
{
  char buf[32];
  unsigned int len = MIN (ARRAY_LENGTH (buf) - 1, (unsigned int) (end - pp));
  strncpy (buf, pp, len);
  buf[len] = '\0';

  char *p = buf;
  char *pend = p;
  int32_t v;

  errno = 0;
  v = strtol (p, &pend, 10);
  if (errno || p == pend || pend - p != end - pp)
    return false;

  *pv = v;
  return true;
}

%%{

action clear_item {
	memset (&info, 0, sizeof (info));
	memset (&pos , 0, sizeof (pos ));
}

action add_item {
	buffer->add_info (info);
	if (buffer->in_error)
	  return false;
	buffer->pos[buffer->len - 1] = pos;
	*end_ptr = p;
}

action tok {
	tok = p;
}

action parse_glyph {
	if (!hb_font_glyph_from_string (font,
					tok, p - tok,
					&info.codepoint))
	  return false;
}

action parse_cluster   { if (!parse_uint (tok, p, &info.cluster )) return false; }
action parse_x_offset  { if (!parse_int  (tok, p, &pos.x_offset )) return false; }
action parse_y_offset  { if (!parse_int  (tok, p, &pos.y_offset )) return false; }
action parse_x_advance { if (!parse_int  (tok, p, &pos.x_advance)) return false; }
action parse_y_advance { if (!parse_int  (tok, p, &pos.y_advance)) return false; }

unum	= '0' | [1-9] digit*;
num	= '-'? unum;

glyph	= alnum+ >tok %parse_glyph;
cluster	= '=' (unum >tok %parse_cluster);
offsets	= '@' (num >tok %parse_x_offset)   ',' (num >tok %parse_y_offset );
advances= '+' (num >tok %parse_x_advance) (',' (num >tok %parse_y_advance))?;
item	=
	(
		glyph
		cluster?
		offsets?
		advances?
	)
	>clear_item
	%add_item
	;

main := space* item (space* '|' space* item)* space* ('|'|']')?;

}%%

static hb_bool_t
_hb_buffer_deserialize_glyphs_text (hb_buffer_t *buffer,
				    const char *buf,
				    unsigned int buf_len,
				    const char **end_ptr,
				    hb_font_t *font)
{
  const char *p = buf, *pe = buf + buf_len;

  /* Ensure we have positions. */
  (void) hb_buffer_get_glyph_positions (buffer, NULL);

#define ISSPACE(c) ((c)==' '||(c)=='\f'||(c)=='\n'||(c)=='\r'||(c)=='\t'||(c)=='\v')
  while (p < pe && ISSPACE (*p))
    p++;
#undef ISSPACE
  if (p < pe && *p == (buffer->len ? '|' : '['))
  {
    *end_ptr = ++p;
  }

  const char *eof = pe, *tok = NULL;
  int cs;
  hb_glyph_info_t info;
  hb_glyph_position_t pos;
  %%{
    write init;
    write exec;
  }%%

  *end_ptr = p;

  return p == pe && *(p-1) != ']';
}

#endif /* HB_BUFFER_DESERIALIZE_TEXT_HH */