/*
 * Copyright (C) 1999-2001, 2016 Free Software Foundation, Inc.
 * This file is part of the GNU LIBICONV Library.
 *
 * The GNU LIBICONV Library is free software; you can redistribute it
 * and/or modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * The GNU LIBICONV Library is distributed in the hope that it will be
 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with the GNU LIBICONV Library; see the file COPYING.LIB.
 * If not, see <https://www.gnu.org/licenses/>.
 */

/*
 * CP922
 */

static const unsigned short cp922_2uni_1[16] = {
  /* 0xa0 */
  0x00a0, 0x00a1, 0x00a2, 0x00a3, 0x00a4, 0x00a5, 0x00a6, 0x00a7,
  0x00a8, 0x00a9, 0x00aa, 0x00ab, 0x00ac, 0x00ad, 0x00ae, 0x203e,
};
static const unsigned short cp922_2uni_2[16] = {
  /* 0xd0 */
  0x0160, 0x00d1, 0x00d2, 0x00d3, 0x00d4, 0x00d5, 0x00d6, 0x00d7,
  0x00d8, 0x00d9, 0x00da, 0x00db, 0x00dc, 0x00dd, 0x017d, 0x00df,
};
static const unsigned short cp922_2uni_3[16] = {
  /* 0xf0 */
  0x0161, 0x00f1, 0x00f2, 0x00f3, 0x00f4, 0x00f5, 0x00f6, 0x00f7,
  0x00f8, 0x00f9, 0x00fa, 0x00fb, 0x00fc, 0x00fd, 0x017e, 0x00ff,
};

static int
cp922_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, size_t n)
{
  unsigned char c = *s;
  if (c < 0xa0)
    *pwc = (ucs4_t) c;
  else if (c < 0xb0)
    *pwc = (ucs4_t) cp922_2uni_1[c-0xa0];
  else if (c < 0xd0)
    *pwc = (ucs4_t) c;
  else if (c < 0xe0)
    *pwc = (ucs4_t) cp922_2uni_2[c-0xd0];
  else if (c < 0xf0)
    *pwc = (ucs4_t) c;
  else
    *pwc = (ucs4_t) cp922_2uni_3[c-0xf0];
  return 1;
}

static const unsigned char cp922_page00[88] = {
  0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0x00, /* 0xa8-0xaf */
  0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* 0xb0-0xb7 */
  0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* 0xb8-0xbf */
  0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, /* 0xc0-0xc7 */
  0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, /* 0xc8-0xcf */
  0x00, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, /* 0xd0-0xd7 */
  0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0x00, 0xdf, /* 0xd8-0xdf */
  0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* 0xe0-0xe7 */
  0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* 0xe8-0xef */
  0x00, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* 0xf0-0xf7 */
  0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0x00, 0xff, /* 0xf8-0xff */
};
static const unsigned char cp922_page01[32] = {
  0xd0, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x60-0x67 */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x68-0x6f */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x70-0x77 */
  0x00, 0x00, 0x00, 0x00, 0x00, 0xde, 0xfe, 0x00, /* 0x78-0x7f */
};

static int
cp922_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, size_t n)
{
  unsigned char c = 0;
  if (wc < 0x00a8) {
    *r = wc;
    return 1;
  }
  else if (wc >= 0x00a8 && wc < 0x0100)
    c = cp922_page00[wc-0x00a8];
  else if (wc >= 0x0160 && wc < 0x0180)
    c = cp922_page01[wc-0x0160];
  else if (wc == 0x203e)
    c = 0xaf;
  if (c != 0) {
    *r = c;
    return 1;
  }
  return RET_ILUNI;
}