/**********************************************************************

  sjis.c -  Oniguruma (regular expression library)

**********************************************************************/

/*-

 * Copyright (c) 2002-2020  K.Kosako

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 */

#include "regint.h"

static const int EncLen_SJIS[] = {

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,

  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,

  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1

};

static const char SJIS_CAN_BE_TRAIL_TABLE[256] = {

  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0

};

#define SJIS_ISMB_FIRST(byte)  (EncLen_SJIS[byte] > 1)

#define SJIS_ISMB_TRAIL(byte)  SJIS_CAN_BE_TRAIL_TABLE[(byte)]

static int

mbc_enc_len(const UChar* p)

{

  return EncLen_SJIS[*p];

}

static int

is_valid_mbc_string(const UChar* p, const UChar* end)

{

  while (p < end) {

    if (*p < 0x80) {

      p++;

    }

    else if (*p < 0xa1) {

      if (*p == 0xa0 || *p == 0x80)

        return FALSE;

      p++;

      if (p >= end) return FALSE;

      if (*p < 0x40 || *p > 0xfc || *p == 0x7f)

        return FALSE;

      p++;

    }

    else if (*p < 0xe0) {

      p++;

    }

    else if (*p < 0xfd) {

      p++;

      if (p >= end) return FALSE;

      if (*p < 0x40 || *p > 0xfc || *p == 0x7f)

        return FALSE;

      p++;

    }

    else

      return FALSE;

  }

  return TRUE;

}

static int

code_to_mbclen(OnigCodePoint code)

{

  if (code < 256) {

    if (EncLen_SJIS[(int )code] == 1)

      return 1;

  }

  else if (code < 0x10000) {

    if (EncLen_SJIS[(int )(code >>  8) & 0xff] == 2)

      return 2;

  }

  return ONIGERR_INVALID_CODE_POINT_VALUE;

}

static OnigCodePoint

mbc_to_code(const UChar* p, const UChar* end)

{

  int c, i, len;

  OnigCodePoint n;

  len = enclen(ONIG_ENCODING_SJIS, p);

  c = *p++;

  n = c;

  if (len == 1) return n;

  for (i = 1; i < len; i++) {

    if (p >= end) break;

    c = *p++;

    n <<= 8;  n += c;

  }

  return n;

}

static int

code_to_mbc(OnigCodePoint code, UChar *buf)

{

  UChar *p = buf;

  if ((code & 0xff00) != 0) *p++ = (UChar )(((code >>  8) & 0xff));

  *p++ = (UChar )(code & 0xff);

  return (int )(p - buf);

}

static int

mbc_case_fold(OnigCaseFoldType flag ARG_UNUSED,

              const UChar** pp, const UChar* end ARG_UNUSED, UChar* lower)

{

  const UChar* p = *pp;

  if (ONIGENC_IS_MBC_ASCII(p)) {

    *lower = ONIGENC_ASCII_CODE_TO_LOWER_CASE(*p);

    (*pp)++;

    return 1;

  }

  else {

    int i;

    int len = enclen(ONIG_ENCODING_SJIS, p);

    for (i = 0; i < len; i++) {

      *lower++ = *p++;

    }

    (*pp) += len;

    return len; /* return byte length of converted char to lower */

  }

}

static UChar*

left_adjust_char_head(const UChar* start, const UChar* s)

{

  const UChar *p;

  int len;

  if (s <= start) return (UChar* )s;

  p = s;

  if (SJIS_ISMB_TRAIL(*p)) {

    while (p > start) {

      if (! SJIS_ISMB_FIRST(*--p)) {

        p++;

        break;

      }

    }

  }

  len = enclen(ONIG_ENCODING_SJIS, p);

  if (p + len > s) return (UChar* )p;

  p += len;

  return (UChar* )(p + ((s - p) & ~1));

}

static int

is_allowed_reverse_match(const UChar* s, const UChar* end ARG_UNUSED)

{

  const UChar c = *s;

  return (SJIS_ISMB_TRAIL(c) ? FALSE : TRUE);

}

static const OnigCodePoint CR_Hiragana[] = {

  1,

  0x829f, 0x82f1

}; /* CR_Hiragana */

static const OnigCodePoint CR_Katakana[] = {

  4,

  0x00a6, 0x00af,

  0x00b1, 0x00dd,

  0x8340, 0x837e,

  0x8380, 0x8396,

}; /* CR_Katakana */

static const OnigCodePoint* PropertyList[] = {

  CR_Hiragana,

  CR_Katakana

};

static int

property_name_to_ctype(OnigEncoding enc, UChar* p, UChar* end)

{

  struct PropertyNameCtype* pc;

  int len = (int )(end - p);

  char q[32];

  if (len < sizeof(q) - 1) {

    xmemcpy(q, p, (size_t )len);

    q[len] = '\0';

    pc = onigenc_sjis_lookup_property_name(q, len);

    if (pc != 0)

      return pc->ctype;

  }

  return ONIGERR_INVALID_CHAR_PROPERTY_NAME;

}

static int

is_code_ctype(OnigCodePoint code, unsigned int ctype)

{

  if (ctype <= ONIGENC_MAX_STD_CTYPE) {

    if (code < 128)

      return ONIGENC_IS_ASCII_CODE_CTYPE(code, ctype);

    else {

      if (CTYPE_IS_WORD_GRAPH_PRINT(ctype)) {

        return (code_to_mbclen(code) > 1 ? TRUE : FALSE);

      }

    }

  }

  else {

    ctype -= (ONIGENC_MAX_STD_CTYPE + 1);

    if (ctype >= (unsigned int )(sizeof(PropertyList)/sizeof(PropertyList[0])))

      return ONIGERR_TYPE_BUG;

    return onig_is_in_code_range((UChar* )PropertyList[ctype], code);

  }

  return FALSE;

}

static int

get_ctype_code_range(OnigCtype ctype, OnigCodePoint* sb_out,

                     const OnigCodePoint* ranges[])

{

  if (ctype <= ONIGENC_MAX_STD_CTYPE) {

    return ONIG_NO_SUPPORT_CONFIG;

  }

  else {

    *sb_out = 0x80;

    ctype -= (ONIGENC_MAX_STD_CTYPE + 1);

    if (ctype >= (OnigCtype )(sizeof(PropertyList)/sizeof(PropertyList[0])))

      return ONIGERR_TYPE_BUG;

    *ranges = PropertyList[ctype];

    return 0;

  }

}

OnigEncodingType OnigEncodingSJIS = {

  mbc_enc_len,

  "Shift_JIS",   /* name */

  2,             /* max enc length */

  1,             /* min enc length */

  onigenc_is_mbc_newline_0x0a,

  mbc_to_code,

  code_to_mbclen,

  code_to_mbc,

  mbc_case_fold,

  onigenc_ascii_apply_all_case_fold,

  onigenc_ascii_get_case_fold_codes_by_str,

  property_name_to_ctype,

  is_code_ctype,

  get_ctype_code_range,

  left_adjust_char_head,

  is_allowed_reverse_match,

  NULL, /* init */

  NULL, /* is_initialized */

  is_valid_mbc_string,

  ENC_FLAG_ASCII_COMPATIBLE|ENC_FLAG_SKIP_OFFSET_1_OR_0,

  0, 0

};