/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * Copyright (C) 2002-2022 Németh László
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * Hunspell is based on MySpell which is Copyright (C) 2002 Kevin Hendricks.
 *
 * Contributor(s): David Einstein, Davide Prina, Giuseppe Modugno,
 * Gianluca Turconi, Simon Brouwer, Noll János, Bíró Árpád,
 * Goldman Eleonóra, Sarlós Tamás, Bencsáth Boldizsár, Halácsy Péter,
 * Dvornik László, Gefferth András, Nagy Viktor, Varga Dániel, Chris Halls,
 * Rene Engelhard, Bram Moolenaar, Dafydd Jones, Harri Pitkänen
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */
/*
 * Copyright 2002 Kevin B. Hendricks, Stratford, Ontario, Canada
 * And Contributors.  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.
 *
 * 3. All modifications to the source code must be clearly marked as
 *    such.  Binary redistributions based on modified source code
 *    must be clearly marked as modified versions in the documentation
 *    and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY KEVIN B. HENDRICKS 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
 * KEVIN B. HENDRICKS 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.
 */

#if defined(MIKTEX_WINDOWS)
#  define MIKTEX_UTF8_WRAP_ALL 1
#  include <miktex/utf8wrap.h>
#endif
#include <cstdlib>
#include <cstring>
#include <cstdio>
#include <cctype>
#include <limits>
#include <sstream>
#if __cplusplus >= 202002L
#include <bit>
#endif

#include "hashmgr.hxx"
#include "csutil.hxx"
#include "atypes.hxx"
#include "langnum.hxx"

// build a hash table from a munched word list

HashMgr::HashMgr(const char* tpath, const char* apath, const char* key)
    : flag_mode(FLAG_CHAR),
      complexprefixes(0),
      utf8(0),
      forbiddenword(FORBIDDENWORD), // forbidden word signing flag
      langnum(0),
      csconv(NULL)
{
  load_config(apath, key);
  if (!csconv)
    csconv = get_current_cs(SPELL_ENCODING);
  int ec = load_tables(tpath, key);
  if (ec) {
    /* error condition - what should we do here */
    HUNSPELL_WARNING(stderr, "Hash Manager Error : %d\n", ec);
    free_table();
    //keep table size to 1 to fix possible division with zero
    tableptr.resize(1, nullptr);
  }
}

void HashMgr::free_flag(unsigned short* astr, short alen) {
  if (astr && (aliasf.empty() || TESTAFF(astr, ONLYUPCASEFLAG, alen)))
    delete[] astr;
}

void HashMgr::free_table() {
  // now pass through hash table freeing up everything
  // go through column by column of the table
  for (auto ptr : tableptr) {
    hentry* nt = NULL;
    while (ptr) {
      nt = ptr->next;
      free_flag(ptr->astr, ptr->alen);
      free(ptr);
      ptr = nt;
    }
  }
  tableptr.clear();
}

HashMgr::~HashMgr() {
  free_table();

  for (auto& j : aliasf)
    delete[] j;
  aliasf.clear();

  for (auto& j : aliasm)
    delete[] j;
  aliasm.clear();

#ifdef MOZILLA_CLIENT
  delete[] csconv;
#endif
}

// lookup a root word in the hashtable

struct hentry* HashMgr::lookup(const char* word, size_t len) const {
  struct hentry* dp = tableptr[hash(word, len)];
  if (!dp)
    return NULL;
  for (; dp != NULL; dp = dp->next) {
    if (strcmp(word, dp->word) == 0)
      return dp;
  }
  return NULL;
}

// add a word to the hash table (private)
int HashMgr::add_word(const std::string& in_word,
                      int wcl,
                      unsigned short* aff,
                      int al,
                      const std::string* in_desc,
                      bool onlyupcase,
                      int captype) {

  if (al > std::numeric_limits<short>::max()) {
    HUNSPELL_WARNING(stderr, "error: affix len %d is over max limit\n", al);
    free_flag(aff, al);
    return 1;
  }

  const std::string* word = &in_word;
  const std::string* desc = in_desc;

  std::string *word_copy = NULL;
  std::string *desc_copy = NULL;
  if ((!ignorechars.empty() && !has_no_ignored_chars(in_word, ignorechars)) || complexprefixes) {
    word_copy = new std::string(in_word);

    if (!ignorechars.empty()) {
      if (utf8) {
        wcl = remove_ignored_chars_utf(*word_copy, ignorechars_utf16);
      } else {
        remove_ignored_chars(*word_copy, ignorechars);
      }
    }

    if (complexprefixes) {
      if (utf8)
        wcl = reverseword_utf(*word_copy);
      else
        reverseword(*word_copy);

      if (in_desc && aliasm.empty()) {
        desc_copy = new std::string(*in_desc);

        if (complexprefixes) {
          if (utf8)
            reverseword_utf(*desc_copy);
          else
            reverseword(*desc_copy);
        }
        desc = desc_copy;
      }
    }

    word = word_copy;
  }

  // limit of hp->blen
  if (word->size() > std::numeric_limits<unsigned char>::max()) {
    HUNSPELL_WARNING(stderr, "error: word len %ld is over max limit\n", word->size());
    delete desc_copy;
    delete word_copy;
    free_flag(aff, al);
    return 1;
  }

  bool upcasehomonym = false;
  int descl = desc ? (!aliasm.empty() ? sizeof(char*) : desc->size() + 1) : 0;
  // variable-length hash record with word and optional fields
  auto hp =
      (struct hentry*)malloc(sizeof(struct hentry) + word->size() + descl);
  if (!hp) {
    delete desc_copy;
    delete word_copy;
    free_flag(aff, al);
    return 1;
  }

  char* hpw = hp->word;
  memcpy(hpw, word->data(), word->size());
  hpw[word->size()] = 0;

  int i = hash(hpw, word->size());

  hp->blen = (unsigned char)word->size();
  hp->clen = (unsigned char)wcl;
  hp->alen = (short)al;
  hp->astr = aff;
  hp->next = NULL;
  hp->next_homonym = NULL;
  hp->var = (captype == INITCAP) ? H_OPT_INITCAP : 0;

  // store the description string or its pointer
  if (desc) {
    hp->var |= H_OPT;
    if (!aliasm.empty()) {
      hp->var |= H_OPT_ALIASM;
      store_pointer(hpw + word->size() + 1, get_aliasm(atoi(desc->c_str())));
    } else {
      strcpy(hpw + word->size() + 1, desc->c_str());
    }
    if (HENTRY_FIND(hp, MORPH_PHON)) {
      hp->var |= H_OPT_PHON;
      // store ph: fields (pronounciation, misspellings, old orthography etc.)
      // of a morphological description in reptable to use in REP replacements.
      size_t predicted = tableptr.size() / MORPH_PHON_RATIO;
      if (reptable.capacity() < predicted)
          reptable.reserve(predicted);
      std::string fields = HENTRY_DATA(hp);
      std::string::const_iterator iter = fields.begin(), start_piece = mystrsep(fields, iter);
      while (start_piece != fields.end()) {
        if (std::string(start_piece, iter).find(MORPH_PHON) == 0) {
          std::string ph = std::string(start_piece, iter).substr(sizeof MORPH_PHON - 1);
          if (!ph.empty()) {
            std::vector<w_char> w;
            size_t strippatt;
            std::string wordpart;
            // dictionary based REP replacement, separated by "->"
            // for example "pretty ph:prity ph:priti->pretti" to handle
            // both prity -> pretty and pritier -> prettiest suggestions.
            if (((strippatt = ph.find("->")) != std::string::npos) &&
                    (strippatt > 0) && (strippatt < ph.size() - 2)) {
                wordpart = ph.substr(strippatt + 2);
                ph.erase(ph.begin() + strippatt, ph.end());
            } else
                wordpart = in_word;
            // when the ph: field ends with the character *,
            // strip last character of the pattern and the replacement
            // to match in REP suggestions also at character changes,
            // for example, "pretty ph:prity*" results "prit->prett"
            // REP replacement instead of "prity->pretty", to get
            // prity->pretty and pritiest->prettiest suggestions.
            if (ph.at(ph.size()-1) == '*') {
              strippatt = 1;
              size_t stripword = 0;
              if (utf8) {
                while ((strippatt < ph.size()) &&
                  ((ph.at(ph.size()-strippatt-1) & 0xc0) == 0x80))
                     ++strippatt;
                while ((stripword < wordpart.size()) &&
                  ((wordpart.at(wordpart.size()-stripword-1) & 0xc0) == 0x80))
                     ++stripword;
              }
              ++strippatt;
              ++stripword;
              if ((ph.size() > strippatt) && (wordpart.size() > stripword)) {
                ph.erase(ph.size()-strippatt, strippatt);
                wordpart.erase(wordpart.size()-stripword, stripword);
              }
            }
            // capitalize lowercase pattern for capitalized words to support
            // good suggestions also for capitalized misspellings, eg.
            // Wednesday ph:wendsay
            // results wendsay -> Wednesday and Wendsay -> Wednesday, too.
            if (captype == INITCAP) {
              std::string ph_capitalized;
              if (utf8) {
                u8_u16(w, ph);
                if (get_captype_utf8(w, langnum) == NOCAP) {
                  mkinitcap_utf(w, langnum);
                  u16_u8(ph_capitalized, w);
                }
              } else if (get_captype(ph, csconv) == NOCAP)
                  mkinitcap(ph_capitalized, csconv);

              if (!ph_capitalized.empty()) {
                // add also lowercase word in the case of German or
                // Hungarian to support lowercase suggestions lowercased by
                // compound word generation or derivational suffixes
                // (for example by adjectival suffix "-i" of geographical
                // names in Hungarian:
                // Massachusetts ph:messzecsuzec
                // messzecsuzeci -> massachusettsi (adjective)
                // For lowercasing by conditional PFX rules, see
                // tests/germancompounding test example or the
                // Hungarian dictionary.)
                if (langnum == LANG_de || langnum == LANG_hu) {
                  std::string wordpart_lower(wordpart);
                  if (utf8) {
                    u8_u16(w, wordpart_lower);
                    mkallsmall_utf(w, langnum);
                    u16_u8(wordpart_lower, w);
                  } else {
                    mkallsmall(wordpart_lower, csconv);
                  }
                  reptable.emplace_back();
                  reptable.back().pattern.assign(ph);
                  reptable.back().outstrings[0].assign(wordpart_lower);
                }
                reptable.emplace_back();
                reptable.back().pattern.assign(ph_capitalized);
                reptable.back().outstrings[0].assign(wordpart);
              }
            }
            reptable.emplace_back();
            reptable.back().pattern.assign(ph);
            reptable.back().outstrings[0].assign(wordpart);
          }
        }
        start_piece = mystrsep(fields, iter);
      }
    }
  }

  struct hentry* dp = tableptr[i];
  if (!dp) {
    tableptr[i] = hp;
    delete desc_copy;
    delete word_copy;
    return 0;
  }
  while (dp->next != NULL) {
    if ((!dp->next_homonym) && (strcmp(hp->word, dp->word) == 0)) {
      // remove hidden onlyupcase homonym
      if (!onlyupcase) {
        if ((dp->astr) && TESTAFF(dp->astr, ONLYUPCASEFLAG, dp->alen)) {
          delete[] dp->astr;
          dp->astr = hp->astr;
          dp->alen = hp->alen;
          free(hp);
          delete desc_copy;
          delete word_copy;
          return 0;
        } else {
          dp->next_homonym = hp;
        }
      } else {
        upcasehomonym = true;
      }
    }
    dp = dp->next;
  }
  if (strcmp(hp->word, dp->word) == 0) {
    // remove hidden onlyupcase homonym
    if (!onlyupcase) {
      if ((dp->astr) && TESTAFF(dp->astr, ONLYUPCASEFLAG, dp->alen)) {
        delete[] dp->astr;
        dp->astr = hp->astr;
        dp->alen = hp->alen;
        free(hp);
        delete desc_copy;
        delete word_copy;
        return 0;
      } else {
        dp->next_homonym = hp;
      }
    } else {
      upcasehomonym = true;
    }
  }
  if (!upcasehomonym) {
    dp->next = hp;
  } else {
    // remove hidden onlyupcase homonym
    delete[] hp->astr;
    free(hp);
  }

  delete desc_copy;
  delete word_copy;
  return 0;
}

int HashMgr::add_hidden_capitalized_word(const std::string& word,
                                         int wcl,
                                         unsigned short* flags,
                                         int flagslen,
                                         const std::string* dp,
                                         int captype) {
  if (flags == NULL)
    flagslen = 0;

  // add inner capitalized forms to handle the following allcap forms:
  // Mixed caps: OpenOffice.org -> OPENOFFICE.ORG
  // Allcaps with suffixes: CIA's -> CIA'S
  if (((captype == HUHCAP) || (captype == HUHINITCAP) ||
       ((captype == ALLCAP) && (flagslen != 0))) &&
      !((flagslen != 0) && TESTAFF(flags, forbiddenword, flagslen))) {
    unsigned short* flags2 = new unsigned short[flagslen + 1];
    flags2[flagslen] = ONLYUPCASEFLAG;
    if (flagslen) {
      memcpy(flags2, flags, flagslen * sizeof(unsigned short));
      std::sort(flags2, flags2 + flagslen + 1);
    }
    if (utf8) {
      std::string st;
      std::vector<w_char> w;
      u8_u16(w, word);
      mkallsmall_utf(w, langnum);
      mkinitcap_utf(w, langnum);
      u16_u8(st, w);
      return add_word(st, wcl, flags2, flagslen + 1, dp, true, INITCAP);
    } else {
      std::string new_word(word);
      mkallsmall(new_word, csconv);
      mkinitcap(new_word, csconv);
      int ret = add_word(new_word, wcl, flags2, flagslen + 1, dp, true, INITCAP);
      return ret;
    }
  }
  return 0;
}

// detect captype and modify word length for UTF-8 encoding
int HashMgr::get_clen_and_captype(const std::string& word, int* captype, std::vector<w_char> &workbuf) {
  int len;
  if (utf8) {
    len = u8_u16(workbuf, word);
    *captype = get_captype_utf8(workbuf, langnum);
  } else {
    len = word.size();
    *captype = get_captype(word, csconv);
  }
  return len;
}

int HashMgr::get_clen_and_captype(const std::string& word, int* captype) {
  std::vector<w_char> workbuf;
  return get_clen_and_captype(word, captype, workbuf);
}

// remove word (personal dictionary function for standalone applications)
int HashMgr::remove(const std::string& word) {
  struct hentry* dp = lookup(word.c_str(), word.size());
  while (dp) {
    if (dp->alen == 0 || !TESTAFF(dp->astr, forbiddenword, dp->alen)) {
      auto flags = new unsigned short[dp->alen + 1];
      for (int i = 0; i < dp->alen; i++)
        flags[i] = dp->astr[i];
      flags[dp->alen] = forbiddenword;
      delete[] dp->astr;
      dp->astr = flags;
      dp->alen++;
      std::sort(flags, flags + dp->alen);
    }
    dp = dp->next_homonym;
  }
  return 0;
}

/* remove forbidden flag to add a personal word to the hash */
int HashMgr::remove_forbidden_flag(const std::string& word) {
  struct hentry* dp = lookup(word.c_str(), word.size());
  if (!dp)
    return 1;
  while (dp) {
    if (dp->astr && TESTAFF(dp->astr, forbiddenword, dp->alen))
      dp->alen = 0;  // XXX forbidden words of personal dic.
    dp = dp->next_homonym;
  }
  return 0;
}

// add a custom dic. word to the hash table (public)
int HashMgr::add(const std::string& word) {
  if (remove_forbidden_flag(word)) {
    int captype, al = 0;
    unsigned short* flags = NULL;
    int wcl = get_clen_and_captype(word, &captype);
    add_word(word, wcl, flags, al, NULL, false, captype);
    return add_hidden_capitalized_word(word, wcl, flags, al, NULL,
                                       captype);
  }
  return 0;
}

int HashMgr::add_with_affix(const std::string& word, const std::string& example) {
  // detect captype and modify word length for UTF-8 encoding
  struct hentry* dp = lookup(example.c_str(), example.size());
  remove_forbidden_flag(word);
  if (dp && dp->astr) {
    int captype;
    int wcl = get_clen_and_captype(word, &captype);
    if (!aliasf.empty()) {
      add_word(word, wcl, dp->astr, dp->alen, NULL, false, captype);
    } else {
      auto flags = new unsigned short[dp->alen];
      memcpy(flags, dp->astr, dp->alen * sizeof(unsigned short));
      add_word(word, wcl, flags, dp->alen, NULL, false, captype);
    }
    return add_hidden_capitalized_word(word, wcl, dp->astr,
                                       dp->alen, NULL, captype);
  }
  return 1;
}

// walk the hash table entry by entry - null at end
// initialize: col=-1; hp = NULL; hp = walk_hashtable(&col, hp);
struct hentry* HashMgr::walk_hashtable(int& col, struct hentry* hp) const {
  if (hp && hp->next != NULL)
    return hp->next;
  for (col++; col < (int)tableptr.size(); ++col) {
    if (tableptr[col])
      return tableptr[col];
  }
  // null at end and reset to start
  col = -1;
  return NULL;
}

// load a munched word list and build a hash table on the fly
int HashMgr::load_tables(const char* tpath, const char* key) {
  // open dictionary file
  FileMgr* dict = new FileMgr(tpath, key);
  if (dict == NULL)
    return 1;

  // first read the first line of file to get hash table size
  std::string ts;
  if (!dict->getline(ts)) {
    HUNSPELL_WARNING(stderr, "error: empty dic file %s\n", tpath);
    delete dict;
    return 2;
  }
  mychomp(ts);

  /* remove byte order mark */
  if (ts.compare(0, 3, "\xEF\xBB\xBF", 3) == 0) {
    ts.erase(0, 3);
  }

  int tablesize = atoi(ts.c_str());

  const int nExtra = 5 + USERWORD;
#if !defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION)
  const int max_allowed = (std::numeric_limits<int>::max() - 1 - nExtra) / int(sizeof(struct hentry*));
#else
  const int max_allowed = (268435456 - 1 - nExtra) / int(sizeof(struct hentry*));
#endif

  if (tablesize <= 0 || tablesize >= max_allowed) {
    HUNSPELL_WARNING(
        stderr, "error: line 1: missing or bad word count in the dic file\n");
    delete dict;
    return 4;
  }
  tablesize += nExtra;
  if ((tablesize & 1) == 0)
    tablesize++;

  // allocate the hash table
  tableptr.resize(tablesize, nullptr);

  // loop through all words on much list and add to hash
  // table and create word and affix strings

  std::vector<w_char> workbuf;

  while (dict->getline(ts)) {
    mychomp(ts);
    // split each line into word and morphological description
    size_t dp_pos = 0;
    while ((dp_pos = ts.find(':', dp_pos)) != std::string::npos) {
      if ((dp_pos > 3) && (ts[dp_pos - 3] == ' ' || ts[dp_pos - 3] == '\t')) {
        for (dp_pos -= 3; dp_pos > 0 && (ts[dp_pos-1] == ' ' || ts[dp_pos-1] == '\t'); --dp_pos)
          ;
        if (dp_pos == 0) {  // missing word
          dp_pos = std::string::npos;
        } else {
          ++dp_pos;
        }
        break;
      }
      ++dp_pos;
    }

    // tabulator is the old morphological field separator
    size_t dp2_pos = ts.find('\t');
    if (dp2_pos != std::string::npos && (dp_pos == std::string::npos || dp2_pos < dp_pos)) {
      dp_pos = dp2_pos + 1;
    }

    std::string dp;
    if (dp_pos != std::string::npos) {
      dp.assign(ts.substr(dp_pos));
      ts.resize(dp_pos - 1);
    }

    // split each line into word and affix char strings
    // "\/" signs slash in words (not affix separator)
    // "/" at beginning of the line is word character (not affix separator)
    size_t ap_pos = ts.find('/');
    while (ap_pos != std::string::npos) {
      if (ap_pos == 0) {
        ++ap_pos;
        continue;
      } else if (ts[ap_pos - 1] != '\\')
        break;
      // replace "\/" with "/"
      ts.erase(ap_pos - 1, 1);
      ap_pos = ts.find('/', ap_pos);
    }

    unsigned short* flags;
    int al;
    if (ap_pos != std::string::npos && ap_pos != ts.size()) {
      std::string ap(ts.substr(ap_pos + 1));
      ts.resize(ap_pos);
      if (!aliasf.empty()) {
        int index = atoi(ap.c_str());
        al = get_aliasf(index, &flags, dict);
        if (!al) {
          HUNSPELL_WARNING(stderr, "error: line %d: bad flag vector alias\n",
                           dict->getlinenum());
        }
      } else {
        al = decode_flags(&flags, ap, dict);
        if (al == -1) {
          HUNSPELL_WARNING(stderr, "Can't allocate memory.\n");
          delete dict;
          return 6;
        }
        std::sort(flags, flags + al);
      }
    } else {
      al = 0;
      flags = NULL;
    }

    int captype;
    int wcl = get_clen_and_captype(ts, &captype, workbuf);
    const std::string *dp_str = dp.empty() ? NULL : &dp;
    // add the word and its index plus its capitalized form optionally
    if (add_word(ts, wcl, flags, al, dp_str, false, captype) ||
        add_hidden_capitalized_word(ts, wcl, flags, al, dp_str, captype)) {
      delete dict;
      return 5;
    }
  }

  delete dict;
  return 0;
}

// the hash function is a simple load and rotate
// algorithm borrowed
int HashMgr::hash(const char* word, size_t len) const {
  unsigned long hv = 0;
  int i = 0;
  while (i < 4 && i < len)
    hv = (hv << 8) | word[i++];
  while (i < len) {
    ROTATE(hv, ROTATE_LEN);
    hv ^= word[i++];
  }
  return (unsigned long)hv % tableptr.size();
}

int HashMgr::decode_flags(unsigned short** result, const std::string& flags, FileMgr* af) const {
  int len;
  if (flags.empty()) {
    *result = NULL;
    return 0;
  }
  switch (flag_mode) {
    case FLAG_LONG: {  // two-character flags (1x2yZz -> 1x 2y Zz)
      len = flags.size();
      if ((len & 1) == 1)
        HUNSPELL_WARNING(stderr, "error: line %d: bad flagvector\n",
                         af->getlinenum());
      len >>= 1;
      *result = new unsigned short[len];
      for (int i = 0; i < len; i++) {
        unsigned short flag = ((unsigned short)((unsigned char)flags[i << 1]) << 8) |
                              ((unsigned short)((unsigned char)flags[(i << 1) | 1]));

        if (flag >= DEFAULTFLAGS) {
          HUNSPELL_WARNING(stderr,
                           "error: line %d: flag id %d is too large (max: %d)\n",
                           af->getlinenum(), flag, DEFAULTFLAGS - 1);
          flag = 0;
        }

        (*result)[i] = flag;
      }
      break;
    }
    case FLAG_NUM: {  // decimal numbers separated by comma (4521,23,233 -> 4521
                      // 23 233)
      len = int(1 + std::count_if(flags.begin(), flags.end(), [](char c) { return c == ','; }));
      *result = new unsigned short[len];
      unsigned short* dest = *result;
      const char* src = flags.c_str();
      for (size_t p = 0; p < flags.size(); ++p) {
        if (flags[p] == ',') {
          int i = atoi(src);
          if (i >= DEFAULTFLAGS) {
            HUNSPELL_WARNING(
                stderr, "error: line %d: flag id %d is too large (max: %d)\n",
                af->getlinenum(), i, DEFAULTFLAGS - 1);
             i = 0;
	  }
          *dest = (unsigned short)i;
          if (*dest == 0)
            HUNSPELL_WARNING(stderr, "error: line %d: 0 is wrong flag id\n",
                             af->getlinenum());
          src = flags.c_str() + p + 1;
          dest++;
        }
      }
      int i = atoi(src);
      if (i >= DEFAULTFLAGS) {
        HUNSPELL_WARNING(stderr,
                         "error: line %d: flag id %d is too large (max: %d)\n",
                         af->getlinenum(), i, DEFAULTFLAGS - 1);
        i = 0;
      }
      *dest = (unsigned short)i;
      if (*dest == 0)
        HUNSPELL_WARNING(stderr, "error: line %d: 0 is wrong flag id\n",
                         af->getlinenum());
      break;
    }
    case FLAG_UNI: {  // UTF-8 characters
      std::vector<w_char> w;
      u8_u16(w, flags);
      len = w.size();
      *result = new unsigned short[len];
#if defined(__i386__) || defined(_M_IX86) || defined(_M_X64)
      memcpy(*result, w.data(), len * sizeof(unsigned short));
#else
      unsigned short* dest = *result;
      for (const w_char wc : w) {
        *dest = (unsigned short)wc;
        dest++;
      }
#endif
      break;
    }
    default: {  // Ispell's one-character flags (erfg -> e r f g)
      len = flags.size();
      *result = new unsigned short[len];
      unsigned short* dest = *result;
      for (const char flag : flags) {
        *dest = (unsigned char)flag;
        dest++;
      }
    }
  }
  return len;
}

bool HashMgr::decode_flags(std::vector<unsigned short>& result, const std::string& flags, FileMgr* af) const {
  if (flags.empty()) {
    return false;
  }
  switch (flag_mode) {
    case FLAG_LONG: {  // two-character flags (1x2yZz -> 1x 2y Zz)
      size_t len = flags.size();
      if ((len & 1) == 1)
        HUNSPELL_WARNING(stderr, "error: line %d: bad flagvector\n",
                         af->getlinenum());
      len >>= 1;
      result.reserve(result.size() + len);
      for (size_t i = 0; i < len; ++i) {
        result.push_back(((unsigned short)((unsigned char)flags[i << 1]) << 8) |
		                 ((unsigned short)((unsigned char)flags[(i << 1) | 1])));
      }
      break;
    }
    case FLAG_NUM: {  // decimal numbers separated by comma (4521,23,233 -> 4521
                      // 23 233)
      const char* src = flags.c_str();
      for (const char* p = src; *p; p++) {
        if (*p == ',') {
          int i = atoi(src);
          if (i >= DEFAULTFLAGS) {
            HUNSPELL_WARNING(
                stderr, "error: line %d: flag id %d is too large (max: %d)\n",
                af->getlinenum(), i, DEFAULTFLAGS - 1);
            i = 0;
	  }
          result.push_back((unsigned short)i);
          if (result.back() == 0)
            HUNSPELL_WARNING(stderr, "error: line %d: 0 is wrong flag id\n",
                             af->getlinenum());
          src = p + 1;
        }
      }
      int i = atoi(src);
      if (i >= DEFAULTFLAGS) {
        HUNSPELL_WARNING(stderr,
                         "error: line %d: flag id %d is too large (max: %d)\n",
                         af->getlinenum(), i, DEFAULTFLAGS - 1);
        i = 0;
      }
      result.push_back((unsigned short)i);
      if (result.back() == 0)
        HUNSPELL_WARNING(stderr, "error: line %d: 0 is wrong flag id\n",
                         af->getlinenum());
      break;
    }
    case FLAG_UNI: {  // UTF-8 characters
      std::vector<w_char> w;
      u8_u16(w, flags);
      size_t len = w.size(), origsize = result.size();
#if defined(__i386__) || defined(_M_IX86) || defined(_M_X64)
      result.resize(origsize + len);
      memcpy(result.data() + origsize, w.data(), len * sizeof(short));
#else
      result.reserve(origsize + len);	
      for (const w_char wc : w) result.push_back((unsigned short)wc);
#endif
      break;
    }
    default: {  // Ispell's one-character flags (erfg -> e r f g)
      result.reserve(flags.size());
      for (const char flag : flags) {
        result.push_back((unsigned char)flag);
      }
    }
  }
  return true;
}

unsigned short HashMgr::decode_flag(const std::string& f) const {
  unsigned short s = 0;
  int i;
  switch (flag_mode) {
    case FLAG_LONG:
      s = ((unsigned short)((unsigned char)f[0]) << 8) | ((unsigned short)((unsigned char)f[1]));
      break;
    case FLAG_NUM:
      i = atoi(f.c_str());
      if (i >= DEFAULTFLAGS) {
        HUNSPELL_WARNING(stderr, "error: flag id %d is too large (max: %d)\n",
                         i, DEFAULTFLAGS - 1);
        i = 0;
      }
      s = (unsigned short)i;
      break;
    case FLAG_UNI: {
      std::vector<w_char> w;
      u8_u16(w, f);
      if (!w.empty())
        s = (unsigned short)w[0];
      break;
    }
    default:
      s = (unsigned char)f[0];
  }
  if (s == 0)
    HUNSPELL_WARNING(stderr, "error: 0 is wrong flag id\n");
  return s;
}

std::string HashMgr::encode_flag(unsigned short f) const {
  if (f == 0)
    return "(NULL)";
  std::string ch;
  if (flag_mode == FLAG_LONG) {
    ch.push_back((unsigned char)(f >> 8));
    ch.push_back((unsigned char)(f - ((f >> 8) << 8)));
  } else if (flag_mode == FLAG_NUM) {
    ch = std::to_string(f); 
  } else if (flag_mode == FLAG_UNI) {

#if defined(__i386__) || defined(_M_IX86) || defined(_M_X64)

#if __cplusplus >= 202002L
    auto wc = std::bit_cast<w_char>(f);
#else
    w_char wc;
    memcpy(&wc, &f, sizeof(unsigned short));
#endif

#else
    w_char wc;
    wc.h = (unsigned char)(f >> 8);
    wc.l = (unsigned char)(f & 0xff);
#endif
    const std::vector<w_char> w = { wc };
    u16_u8(ch, w);
  } else {
    ch.push_back((unsigned char)(f));
  }
  return ch;
}

// read in aff file and set flag mode
int HashMgr::load_config(const char* affpath, const char* key) {
  int firstline = 1;

  // open the affix file
  FileMgr* afflst = new FileMgr(affpath, key);
  if (!afflst) {
    HUNSPELL_WARNING(
        stderr, "Error - could not open affix description file %s\n", affpath);
    return 1;
  }

  // read in each line ignoring any that do not
  // start with a known line type indicator

  std::string line;
  while (afflst->getline(line)) {
    mychomp(line);

    /* remove byte order mark */
    if (firstline) {
      firstline = 0;
      if (line.compare(0, 3, "\xEF\xBB\xBF", 3) == 0) {
        line.erase(0, 3);
      }
    }

    /* parse in the try string */
    if ((line.compare(0, 4, "FLAG", 4) == 0) && line.size() > 4 && isspace(line[4])) {
      if (flag_mode != FLAG_CHAR) {
        HUNSPELL_WARNING(stderr,
                         "error: line %d: multiple definitions of the FLAG "
                         "affix file parameter\n",
                         afflst->getlinenum());
      }
      if (line.find("long") != std::string::npos)
        flag_mode = FLAG_LONG;
      if (line.find("num") != std::string::npos)
        flag_mode = FLAG_NUM;
      if (line.find("UTF-8") != std::string::npos)
        flag_mode = FLAG_UNI;
      if (flag_mode == FLAG_CHAR) {
        HUNSPELL_WARNING(
            stderr,
            "error: line %d: FLAG needs `num', `long' or `UTF-8' parameter\n",
            afflst->getlinenum());
      }
    }

    if (line.compare(0, 13, "FORBIDDENWORD", 13) == 0) {
      std::string st;
      if (!parse_string(line, st, afflst->getlinenum())) {
        delete afflst;
        return 1;
      }
      forbiddenword = decode_flag(st);
    }

    if (line.compare(0, 3, "SET", 3) == 0) {
      if (!parse_string(line, enc, afflst->getlinenum())) {
        delete afflst;
        return 1;
      }
      if (enc == "UTF-8") {
        utf8 = 1;
      } else
        csconv = get_current_cs(enc);
    }

    if (line.compare(0, 4, "LANG", 4) == 0) {
      if (!parse_string(line, lang, afflst->getlinenum())) {
        delete afflst;
        return 1;
      }
      langnum = get_lang_num(lang);
    }

    /* parse in the ignored characters (for example, Arabic optional diacritics
     * characters */
    if (line.compare(0, 6, "IGNORE", 6) == 0) {
      if (!parse_array(line, ignorechars, ignorechars_utf16,
                       utf8, afflst->getlinenum())) {
        delete afflst;
        return 1;
      }
    }

    if ((line.compare(0, 2, "AF", 2) == 0) && line.size() > 2 && isspace(line[2])) {
      if (!parse_aliasf(line, afflst)) {
        delete afflst;
        return 1;
      }
    }

    if ((line.compare(0, 2, "AM", 2) == 0) && line.size() > 2 && isspace(line[2])) {
      if (!parse_aliasm(line, afflst)) {
        delete afflst;
        return 1;
      }
    }

    if (line.compare(0, 15, "COMPLEXPREFIXES", 15) == 0)
      complexprefixes = 1;

    /* parse in the typical fault correcting table */
    if (line.compare(0, 3, "REP", 3) == 0) {
      if (!parse_reptable(line, afflst)) {
        delete afflst;
        return 1;
      }
    }

    // don't check the full affix file, yet
    if (((line.compare(0, 3, "SFX", 3) == 0) ||
         (line.compare(0, 3, "PFX", 3) == 0)) &&
            line.size() > 3 && isspace(line[3]) &&
            !reptable.empty()) // (REP table is in the end of Afrikaans aff file)
      break;
  }

  delete afflst;
  return 0;
}

/* parse in the ALIAS table */
bool HashMgr::parse_aliasf(const std::string& line, FileMgr* af) {
  if (!aliasf.empty()) {
    HUNSPELL_WARNING(stderr, "error: line %d: multiple table definitions\n",
                     af->getlinenum());
    return false;
  }
  int i = 0, np = 0, numaliasf = 0;
  auto iter = line.begin(), start_piece = mystrsep(line, iter);
  while (start_piece != line.end()) {
    switch (i) {
      case 0: {
        np++;
        break;
      }
      case 1: {
        numaliasf = atoi(std::string(start_piece, iter).c_str());
        if (numaliasf < 1) {
          aliasf.clear();
          aliasflen.clear();
          HUNSPELL_WARNING(stderr, "error: line %d: bad entry number\n",
                           af->getlinenum());
          return false;
        }
        aliasf.reserve(std::min(numaliasf, 16384));
        aliasflen.reserve(std::min(numaliasf, 16384));
        np++;
        break;
      }
      default:
        break;
    }
    ++i;
    start_piece = mystrsep(line, iter);
  }
  if (np != 2) {
    aliasf.clear();
    aliasflen.clear();
    HUNSPELL_WARNING(stderr, "error: line %d: missing data\n",
                     af->getlinenum());
    return false;
  }

  /* now parse the numaliasf lines to read in the remainder of the table */
  for (int j = 0; j < numaliasf; ++j) {
    std::string nl;
    unsigned short* alias = NULL;
    unsigned aliaslen = 0;
    i = 0;
    if (af->getline(nl)) {
      mychomp(nl);
      iter = nl.begin();
      start_piece = mystrsep(nl, iter);
      bool errored = false;
      while (!errored && start_piece != nl.end()) {
        switch (i) {
          case 0: {
            if (nl.compare(start_piece - nl.begin(), 2, "AF", 2) != 0) {
              errored = true;
              break;
            }
            break;
          }
          case 1: {
            std::string piece(start_piece, iter);
            aliaslen =
                (unsigned short)decode_flags(&alias, piece, af);
            std::sort(alias, alias + aliaslen);
            break;
          }
          default:
            break;
        }
        ++i;
        start_piece = mystrsep(nl, iter);
      }
    }
    if (!alias) {
      for (int k = 0; k < j; ++k) {
        delete[] aliasf[k];
      }
      aliasf.clear();
      aliasflen.clear();
      HUNSPELL_WARNING(stderr, "error: line %d: table is corrupt\n",
                       af->getlinenum());
      return false;
    }

    aliasf.push_back(alias);
    aliasflen.push_back(aliaslen);
  }
  return true;
}

int HashMgr::is_aliasf() const {
  return !aliasf.empty();
}

int HashMgr::get_aliasf(int index, unsigned short** fvec, FileMgr* af) const {
  if (index > 0 && static_cast<size_t>(index) <= aliasflen.size()) {
    *fvec = aliasf[index - 1];
    return aliasflen[index - 1];
  }
  HUNSPELL_WARNING(stderr, "error: line %d: bad flag alias index: %d\n",
                   af->getlinenum(), index);
  *fvec = NULL;
  return 0;
}

/* parse morph alias definitions */
bool HashMgr::parse_aliasm(const std::string& line, FileMgr* af) {
  if (!aliasm.empty()) {
    HUNSPELL_WARNING(stderr, "error: line %d: multiple table definitions\n",
                     af->getlinenum());
    return false;
  }
  int i = 0, np = 0, numaliasm = 0;
  auto iter = line.begin(), start_piece = mystrsep(line, iter);
  while (start_piece != line.end()) {
    switch (i) {
      case 0: {
        np++;
        break;
      }
      case 1: {
        numaliasm = atoi(std::string(start_piece, iter).c_str());
        if (numaliasm < 1) {
          HUNSPELL_WARNING(stderr, "error: line %d: bad entry number\n",
                           af->getlinenum());
          return false;
        }
        aliasm.reserve(std::min(numaliasm, 16384));
        np++;
        break;
      }
      default:
        break;
    }
    ++i;
    start_piece = mystrsep(line, iter);
  }
  if (np != 2) {
    aliasm.clear();
    HUNSPELL_WARNING(stderr, "error: line %d: missing data\n",
                     af->getlinenum());
    return false;
  }

  /* now parse the numaliasm lines to read in the remainder of the table */
  for (int j = 0; j < numaliasm; ++j) {
    std::string nl;
    char* alias = NULL;
    if (af->getline(nl)) {
      mychomp(nl);
      iter = nl.begin();
      i = 0;
      start_piece = mystrsep(nl, iter);
      bool errored = false;
      while (!errored && start_piece != nl.end()) {
        switch (i) {
          case 0: {
            if (nl.compare(start_piece - nl.begin(), 2, "AM", 2) != 0) {
              errored = true;
              break;
            }
            break;
          }
          case 1: {
            // add the remaining of the line
            std::string::const_iterator end = nl.end();
            std::string chunk(start_piece, end);
            if (complexprefixes) {
              if (utf8)
                reverseword_utf(chunk);
              else
                reverseword(chunk);
            }
            size_t sl = chunk.size() + 1;
            alias = new char[sl];
            memcpy(alias, chunk.c_str(), sl);
            break;
          }
          default:
            break;
        }
        ++i;
        start_piece = mystrsep(nl, iter);
      }
    }
    if (!alias) {
      for (int k = 0; k < j; ++k) {
        delete[] aliasm[k];
      }
      aliasm.clear();
      HUNSPELL_WARNING(stderr, "error: line %d: table is corrupt\n",
                       af->getlinenum());
      return false;
    }
    aliasm.push_back(alias);
  }
  return true;
}

int HashMgr::is_aliasm() const {
  return !aliasm.empty();
}

char* HashMgr::get_aliasm(int index) const {
  if (index > 0 && static_cast<size_t>(index) <= aliasm.size())
    return aliasm[index - 1];
  HUNSPELL_WARNING(stderr, "error: bad morph. alias index: %d\n", index);
  return NULL;
}

/* parse in the typical fault correcting table */
bool HashMgr::parse_reptable(const std::string& line, FileMgr* af) {
  if (!reptable.empty()) {
    HUNSPELL_WARNING(stderr, "error: line %d: multiple table definitions\n",
                     af->getlinenum());
    return false;
  }
  int numrep = -1, i = 0, np = 0;
  auto iter = line.begin(), start_piece = mystrsep(line, iter);
  while (start_piece != line.end()) {
    switch (i) {
      case 0: {
        np++;
        break;
      }
      case 1: {
        numrep = atoi(std::string(start_piece, iter).c_str());
        if (numrep < 1) {
          HUNSPELL_WARNING(stderr, "error: line %d: incorrect entry number\n",
                           af->getlinenum());
          return false;
        }
        reptable.reserve(std::min(numrep, 16384));
        np++;
        break;
      }
      default:
        break;
    }
    ++i;
    start_piece = mystrsep(line, iter);
  }
  if (np != 2) {
    HUNSPELL_WARNING(stderr, "error: line %d: missing data\n",
                     af->getlinenum());
    return false;
  }

  /* now parse the numrep lines to read in the remainder of the table */
  for (int j = 0; j < numrep; ++j) {
    std::string nl;
    reptable.emplace_back();
    int type = 0;
    if (af->getline(nl)) {
      mychomp(nl);
      iter = nl.begin();
      i = 0;
      start_piece = mystrsep(nl, iter);
      bool errored = false;
      while (!errored && start_piece != nl.end()) {
        switch (i) {
          case 0: {
            if (nl.compare(start_piece - nl.begin(), 3, "REP", 3) != 0) {
              errored = true;
              break;
            }
            break;
          }
          case 1: {
            if (*start_piece == '^')
              type = 1;
            reptable.back().pattern.assign(start_piece + type, iter);
            mystrrep(reptable.back().pattern, "_", " ");
            if (!reptable.back().pattern.empty() && reptable.back().pattern[reptable.back().pattern.size() - 1] == '$') {
              type += 2;
              reptable.back().pattern.resize(reptable.back().pattern.size() - 1);
            }
            break;
          }
          case 2: {
            reptable.back().outstrings[type].assign(start_piece, iter);
            mystrrep(reptable.back().outstrings[type], "_", " ");
            break;
          }
          default:
            break;
        }
        ++i;
        start_piece = mystrsep(nl, iter);
      }
    }
    if (reptable.back().pattern.empty() || reptable.back().outstrings[type].empty()) {
      HUNSPELL_WARNING(stderr, "error: line %d: table is corrupt\n",
                       af->getlinenum());
      reptable.clear();
      return false;
    }
  }
  return true;
}

// return replacing table
const std::vector<replentry>& HashMgr::get_reptable() const {
  return reptable;
}
