/*
 * Copyright (C) 1999-2001 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 Library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with the GNU LIBICONV Library; see the file COPYING.LIB.
 * If not, write to the Free Software Foundation, Inc., 59 Temple Place -
 * Suite 330, Boston, MA 02111-1307, USA.
 */

/*
 * CP1258
 */

#include "flushwc.h"
#include "vietcomb.h"

static const unsigned char cp1258_comb_table[] = {
  0xcc, 0xec, 0xde, 0xd2, 0xf2,
};

static const unsigned short cp1258_2uni[128] = {
  /* 0x80 */
  0x20ac, 0xfffd, 0x201a, 0x0192, 0x201e, 0x2026, 0x2020, 0x2021,
  0x02c6, 0x2030, 0xfffd, 0x2039, 0x0152, 0xfffd, 0xfffd, 0xfffd,
  /* 0x90 */
  0xfffd, 0x2018, 0x2019, 0x201c, 0x201d, 0x2022, 0x2013, 0x2014,
  0x02dc, 0x2122, 0xfffd, 0x203a, 0x0153, 0xfffd, 0xfffd, 0x0178,
  /* 0xa0 */
  0x00a0, 0x00a1, 0x00a2, 0x00a3, 0x00a4, 0x00a5, 0x00a6, 0x00a7,
  0x00a8, 0x00a9, 0x00aa, 0x00ab, 0x00ac, 0x00ad, 0x00ae, 0x00af,
  /* 0xb0 */
  0x00b0, 0x00b1, 0x00b2, 0x00b3, 0x00b4, 0x00b5, 0x00b6, 0x00b7,
  0x00b8, 0x00b9, 0x00ba, 0x00bb, 0x00bc, 0x00bd, 0x00be, 0x00bf,
  /* 0xc0 */
  0x00c0, 0x00c1, 0x00c2, 0x0102, 0x00c4, 0x00c5, 0x00c6, 0x00c7,
  0x00c8, 0x00c9, 0x00ca, 0x00cb, 0x0300, 0x00cd, 0x00ce, 0x00cf,
  /* 0xd0 */
  0x0110, 0x00d1, 0x0309, 0x00d3, 0x00d4, 0x01a0, 0x00d6, 0x00d7,
  0x00d8, 0x00d9, 0x00da, 0x00db, 0x00dc, 0x01af, 0x0303, 0x00df,
  /* 0xe0 */
  0x00e0, 0x00e1, 0x00e2, 0x0103, 0x00e4, 0x00e5, 0x00e6, 0x00e7,
  0x00e8, 0x00e9, 0x00ea, 0x00eb, 0x0301, 0x00ed, 0x00ee, 0x00ef,
  /* 0xf0 */
  0x0111, 0x00f1, 0x0323, 0x00f3, 0x00f4, 0x01a1, 0x00f6, 0x00f7,
  0x00f8, 0x00f9, 0x00fa, 0x00fb, 0x00fc, 0x01b0, 0x20ab, 0x00ff,
};

/* In the CP1258 to Unicode direction, the state contains a buffered
 * character, or 0 if none. */

static int cp1258_mbtowc (conv_t conv, ucs4_t * pwc, const unsigned char *s, int n)
{
  unsigned char c = *s;
  unsigned short wc;
  unsigned short last_wc;

  if (c < 0x80)
  {
    wc = c;
  }
  else
  {
    wc = cp1258_2uni[c - 0x80];
    if (wc == 0xfffd)
      return RET_ILSEQ;
  }
  last_wc = conv->istate;
  if (last_wc)
  {
    if (wc >= 0x0300 && wc < 0x0340)
    {
      /* See whether last_wc and wc can be combined. */
      unsigned int k = 0;
      unsigned int i1, i2;

      switch (wc)
      {
        case 0x0300:
             k = 0;
             break;
        case 0x0301:
             k = 1;
             break;
        case 0x0303:
             k = 2;
             break;
        case 0x0309:
             k = 3;
             break;
        case 0x0323:
             k = 4;
             break;
        default:
             abort();
      }
      i1 = viet_comp_table[k].idx;
      i2 = i1 + viet_comp_table[k].len - 1;
      if (last_wc >= viet_comp_table_data[i1].base && last_wc <= viet_comp_table_data[i2].base)
      {
        unsigned int i;

        for (;;)
        {
          i = (i1 + i2) >> 1;
          if (last_wc == viet_comp_table_data[i].base)
            break;
          if (last_wc < viet_comp_table_data[i].base)
          {
            if (i1 == i)
              goto not_combining;
            i2 = i;
          }
          else
          {
            if (i1 != i)
              i1 = i;
            else
            {
              i = i2;
              if (last_wc == viet_comp_table_data[i].base)
                break;
              goto not_combining;
            }
          }
        }
        last_wc = viet_comp_table_data[i].composed;
        /* Output the combined character. */
        conv->istate = 0;
        *pwc = (ucs4_t) last_wc;
        return (1);
      }
    }
  not_combining:
    /* Output the buffered character. */
    conv->istate = 0;
    *pwc = (ucs4_t) last_wc;
    return 0;                   /* Don't advance the input pointer. */
  }
  if (wc >= 0x0041 && wc <= 0x01b0)
  {
    /* wc is a possible match in viet_comp_table_data. Buffer it. */
    conv->istate = wc;
    return RET_TOOFEW (1);
  }
  else
  {
    /* Output wc immediately. */
    *pwc = (ucs4_t) wc;
    ARGSUSED (n);
    return (1);
  }
}

#define cp1258_flushwc normal_flushwc

static const unsigned char cp1258_page00[88] = {
  0xc0, 0xc1, 0xc2, 0x00, 0xc4, 0xc5, 0xc6, 0xc7, /* 0xc0-0xc7 */
  0xc8, 0xc9, 0xca, 0xcb, 0x00, 0xcd, 0xce, 0xcf, /* 0xc8-0xcf */
  0x00, 0xd1, 0x00, 0xd3, 0xd4, 0x00, 0xd6, 0xd7, /* 0xd0-0xd7 */
  0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0x00, 0x00, 0xdf, /* 0xd8-0xdf */
  0xe0, 0xe1, 0xe2, 0x00, 0xe4, 0xe5, 0xe6, 0xe7, /* 0xe0-0xe7 */
  0xe8, 0xe9, 0xea, 0xeb, 0x00, 0xed, 0xee, 0xef, /* 0xe8-0xef */
  0x00, 0xf1, 0x00, 0xf3, 0xf4, 0x00, 0xf6, 0xf7, /* 0xf0-0xf7 */
  0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0x00, 0x00, 0xff, /* 0xf8-0xff */
  /* 0x0100 */
  0x00, 0x00, 0xc3, 0xe3, 0x00, 0x00, 0x00, 0x00, /* 0x00-0x07 */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x08-0x0f */
  0xd0, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x10-0x17 */
};
static const unsigned char cp1258_page01[104] = {
  0x00, 0x00, 0x8c, 0x9c, 0x00, 0x00, 0x00, 0x00, /* 0x50-0x57 */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x58-0x5f */
  0x00, 0x00, 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 */
  0x9f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x78-0x7f */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x80-0x87 */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x88-0x8f */
  0x00, 0x00, 0x83, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x90-0x97 */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x98-0x9f */
  0xd5, 0xf5, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0xa0-0xa7 */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xdd, /* 0xa8-0xaf */
  0xfd, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0xb0-0xb7 */
};
static const unsigned char cp1258_page02[32] = {
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x88, 0x00, /* 0xc0-0xc7 */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0xc8-0xcf */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0xd0-0xd7 */
  0x00, 0x00, 0x00, 0x00, 0x98, 0x00, 0x00, 0x00, /* 0xd8-0xdf */
};
static const unsigned char cp1258_page03[40] = {
  0xcc, 0xec, 0x00, 0xde, 0x00, 0x00, 0x00, 0x00, /* 0x00-0x07 */
  0x00, 0xd2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x08-0x0f */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x10-0x17 */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x18-0x1f */
  0x00, 0x00, 0x00, 0xf2, 0x00, 0x00, 0x00, 0x00, /* 0x20-0x27 */
};
static const unsigned char cp1258_page20[48] = {
  0x00, 0x00, 0x00, 0x96, 0x97, 0x00, 0x00, 0x00, /* 0x10-0x17 */
  0x91, 0x92, 0x82, 0x00, 0x93, 0x94, 0x84, 0x00, /* 0x18-0x1f */
  0x86, 0x87, 0x95, 0x00, 0x00, 0x00, 0x85, 0x00, /* 0x20-0x27 */
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x28-0x2f */
  0x89, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x30-0x37 */
  0x00, 0x8b, 0x9b, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x38-0x3f */
};

static int cp1258_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n)
{
  unsigned char c = 0;

  if (wc < 0x0080)
  {
    *r = wc;
    return (1);
  }
  else if (wc >= 0x00a0 && wc < 0x00c0)
    c = wc;
  else if (wc >= 0x00c0 && wc < 0x0118)
    c = cp1258_page00[wc - 0x00c0];
  else if (wc >= 0x0150 && wc < 0x01b8)
    c = cp1258_page01[wc - 0x0150];
  else if (wc >= 0x02c0 && wc < 0x02e0)
    c = cp1258_page02[wc - 0x02c0];
  else if (wc >= 0x0300 && wc < 0x0328)
    c = cp1258_page03[wc - 0x0300];
  else if (wc >= 0x0340 && wc < 0x0342) /* deprecated Vietnamese tone marks */
    c = cp1258_page03[wc - 0x0340];
  else if (wc >= 0x2010 && wc < 0x2040)
    c = cp1258_page20[wc - 0x2010];
  else if (wc == 0x20ab)
    c = 0xfe;
  else if (wc == 0x20ac)
    c = 0x80;
  else if (wc == 0x2122)
    c = 0x99;
  if (c != 0)
  {
    *r = c;
    return (1);
  }
  /* Try canonical decomposition. */
  {
    /* Binary search through viet_decomp_table. */
    unsigned int i1 = 0;
    unsigned int i2 = sizeof (viet_decomp_table) / sizeof (viet_decomp_table[0]) - 1;

    if (wc >= viet_decomp_table[i1].composed && wc <= viet_decomp_table[i2].composed)
    {
      unsigned int i;

      for (;;)
      {
        /* Here i2 - i1 > 0. */
        i = (i1 + i2) >> 1;
        if (wc == viet_decomp_table[i].composed)
          break;
        if (wc < viet_decomp_table[i].composed)
        {
          if (i1 == i)
            return RET_ILUNI;
          /* Here i1 < i < i2. */
          i2 = i;
        }
        else
        {
          /* Here i1 <= i < i2. */
          if (i1 != i)
            i1 = i;
          else
          {
            /* Here i2 - i1 = 1. */
            i = i2;
            if (wc == viet_decomp_table[i].composed)
              break;
            else
              return RET_ILUNI;
          }
        }
      }
      /* Found a canonical decomposition. */
      wc = viet_decomp_table[i].base;
      /* wc is one of 0x0020, 0x0041..0x005a, 0x0061..0x007a, 0x00a5, 0x00a8,
       * 0x00c2, 0x00c5..0x00c7, 0x00ca, 0x00cf, 0x00d3, 0x00d4, 0x00d6,
       * 0x00d8, 0x00da, 0x00dc, 0x00e2, 0x00e5..0x00e7, 0x00ea, 0x00ef,
       * 0x00f3, 0x00f4, 0x00f6, 0x00f8, 0x00fc, 0x0102, 0x0103, 0x01a0,
       * 0x01a1, 0x01af, 0x01b0. */
      if (wc < 0x0100)
        c = wc;
      else if (wc < 0x0118)
        c = cp1258_page00[wc - 0x00c0];
      else
        c = cp1258_page01[wc - 0x0150];
      if (n < 2)
        return RET_TOOSMALL;
      r[0] = c;
      r[1] = cp1258_comb_table[viet_decomp_table[i].comb1];
      return (2);
    }
  }
  ARGSUSED (conv);
  return RET_ILUNI;
}
