/*-------------------------------------------------------------------------

 *

 * dict_ispell.c

 *    Ispell dictionary interface

 *

 * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group

 *

 *

 * IDENTIFICATION

 *    src/backend/tsearch/dict_ispell.c

 *

 *-------------------------------------------------------------------------

 */

#include "postgres.h"

#include "catalog/pg_collation_d.h"

#include "commands/defrem.h"

#include "tsearch/dicts/spell.h"

#include "tsearch/ts_public.h"

#include "utils/fmgrprotos.h"

#include "utils/formatting.h"

typedef struct

{

  StopList  stoplist;

  IspellDict  obj;

} DictISpell;

Datum

dispell_init(PG_FUNCTION_ARGS)

{

  List     *dictoptions = (List *) PG_GETARG_POINTER(0);

  DictISpell *d;

  bool    affloaded = false,

        dictloaded = false,

        stoploaded = false;

  ListCell   *l;

  d = (DictISpell *) palloc0(sizeof(DictISpell));

  NIStartBuild(&(d->obj));

  foreach(l, dictoptions)

  {

    DefElem    *defel = (DefElem *) lfirst(l);

    if (strcmp(defel->defname, "dictfile") == 0)

    {

      char     *filename;

      if (dictloaded)

        ereport(ERROR,

            (errcode(ERRCODE_INVALID_PARAMETER_VALUE),

             errmsg("multiple DictFile parameters")));

      filename = get_tsearch_config_filename(defGetString(defel),

                           "dict");

      NIImportDictionary(&(d->obj), filename);

      pfree(filename);

      dictloaded = true;

    }

    else if (strcmp(defel->defname, "afffile") == 0)

    {

      char     *filename;

      if (affloaded)

        ereport(ERROR,

            (errcode(ERRCODE_INVALID_PARAMETER_VALUE),

             errmsg("multiple AffFile parameters")));

      filename = get_tsearch_config_filename(defGetString(defel),

                           "affix");

      NIImportAffixes(&(d->obj), filename);

      pfree(filename);

      affloaded = true;

    }

    else if (strcmp(defel->defname, "stopwords") == 0)

    {

      if (stoploaded)

        ereport(ERROR,

            (errcode(ERRCODE_INVALID_PARAMETER_VALUE),

             errmsg("multiple StopWords parameters")));

      readstoplist(defGetString(defel), &(d->stoplist), str_tolower);

      stoploaded = true;

    }

    else

    {

      ereport(ERROR,

          (errcode(ERRCODE_INVALID_PARAMETER_VALUE),

           errmsg("unrecognized Ispell parameter: \"%s\"",

              defel->defname)));

    }

  }

  if (affloaded && dictloaded)

  {

    NISortDictionary(&(d->obj));

    NISortAffixes(&(d->obj));

  }

  else if (!affloaded)

  {

    ereport(ERROR,

        (errcode(ERRCODE_INVALID_PARAMETER_VALUE),

         errmsg("missing AffFile parameter")));

  }

  else

  {

    ereport(ERROR,

        (errcode(ERRCODE_INVALID_PARAMETER_VALUE),

         errmsg("missing DictFile parameter")));

  }

  NIFinishBuild(&(d->obj));

  PG_RETURN_POINTER(d);

}

Datum

dispell_lexize(PG_FUNCTION_ARGS)

{

  DictISpell *d = (DictISpell *) PG_GETARG_POINTER(0);

  char     *in = (char *) PG_GETARG_POINTER(1);

  int32   len = PG_GETARG_INT32(2);

  char     *txt;

  TSLexeme   *res;

  TSLexeme   *ptr,

         *cptr;

  if (len <= 0)

    PG_RETURN_POINTER(NULL);

  txt = str_tolower(in, len, DEFAULT_COLLATION_OID);

  res = NINormalizeWord(&(d->obj), txt);

  if (res == NULL)

    PG_RETURN_POINTER(NULL);

  cptr = res;

  for (ptr = cptr; ptr->lexeme; ptr++)

  {

    if (searchstoplist(&(d->stoplist), ptr->lexeme))

    {

      pfree(ptr->lexeme);

      ptr->lexeme = NULL;

    }

    else

    {

      if (cptr != ptr)

        memcpy(cptr, ptr, sizeof(TSLexeme));

      cptr++;

    }

  }

  cptr->lexeme = NULL;

  PG_RETURN_POINTER(res);

}