/* mimx-anthy.c -- Anthy input method external module.	-*- coding: euc-jp; -*-
   Copyright (C) 2003, 2004
     National Institute of Advanced Industrial Science and Technology (AIST)
     Registration Number H15PRO112

   This file is part of the m17n library.

   The m17n 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 2.1 of
   the License, or (at your option) any later version.

   The m17n 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 m17n library; if not, write to the Free
   Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   02111-1307, USA.  */

/***en
    @enpage mimx-anthy external module for the input method <ja, anthy>

    @section mimx-anthy-description DESCRIPTION

    The shared library mimx-anthy.so is an external module used by the
    input method <ja, anthy>.  It exports these functions.

    <ul>
    <li> init

    Initialize this module.

    <li> fini

    Finalize this module.

    <li> convert

    Convert the current preedit text (Hiragana sequence) into
    Kana-Kanji mixed text.

    <li> change

    Record the change of candidate of the current segment.

    <li> resize

    Enlarge or shorten the length of the current segment.

    <li> commit

    Commit the lastly selected candidates of all the segments.

    </ul>

    @section mimx-anthy-seealso See also
    @ref mdbIM
*/
/***ja
    @japage mimx-anthy 入力メソッド <ja, anthy> 用外部モジュール.

    @section mimx-anthy-description DESCRIPTION

    共有ライブラリ mimx-anthy.so は入力メソッド<ja, anthy> に用いられ 
    る外部モジュールであり、以下の関数を export している。

    <ul>
    <li> init

    モジュールの初期化。 

    <li> fini

    モジュールの終了。 

    <li> convert

    現在の preedit テキスト (ひらがな列) をかな漢字テキストに変換する。 

    <li> change

    現在のセグメントの候補の変遷を記録する。 

    <li> resize

    現在のセグメントの長さを変更する。 

    <li> commit

    全セグメントの最新の候補をコミットする。

    </ul>

    @section mimx-anthy-seealso 参照
    @ref mdbIM
*/

#ifndef FOR_DOXYGEN

#include <stdio.h>
#include <string.h>
#include <m17n.h>

#ifdef HAVE_ANTHY

#include <anthy/anthy.h>

static int initialized;
static MSymbol Manthy, Msegment;

/* A structure to record in MInputContext->plist with key Manthy.  */

typedef struct {
  MInputContext *ic;
  anthy_context_t ac;
  /* Which candidate is selected in each segment.  */
  int *candidate_numbers;
  /* Size of the above array.  */
  int num_segments;
  /* Converter for this context.  */
  MConverter *converter;
} AnthyContext;

static AnthyContext *
new_context (MInputContext *ic)
{
  AnthyContext *context;
  anthy_context_t ac;
  MSymbol euc_jp = msymbol ("euc-jp");
  /* Rebound to an actual buffer just before being used.  */
  MConverter *converter = mconv_buffer_converter (euc_jp, NULL, 0);

  if (! converter)
    return NULL;
  ac = anthy_create_context ();
  if (! ac)
    return NULL;
  context = calloc (1, sizeof (AnthyContext));
  context->ic = ic;
  context->ac = ac;
  context->num_segments = 0;
  context->candidate_numbers = NULL;
  context->converter = converter;
  return context;
}

static AnthyContext *
get_context (MInputContext *ic)
{
  MPlist *plist = ic->plist;
  AnthyContext *context;

  for (; plist && mplist_key (plist) != Mnil; plist = mplist_next (plist))
    {
      if (mplist_key (plist) != Manthy)
	continue;
      context = mplist_value (plist);
      if (context->ic == ic)
	return context;
    }
  return NULL;
}


static void
free_context (AnthyContext *context)
{
  anthy_release_context (context->ac);
  if (context->candidate_numbers)
    free (context->candidate_numbers);
  mconv_free_converter (context->converter);
  free (context);
}

static void
allocate_candidate_numbers (AnthyContext *context, int num)
{
  if (context->num_segments < num)
    {
      if (context->num_segments == 0)
	context->candidate_numbers = malloc (sizeof (int) * num);
      else
	context->candidate_numbers = realloc (context->candidate_numbers,
					      sizeof (int) * num);
      context->num_segments = num;
    }
}

static void
add_action (MPlist *actions, MSymbol name, MSymbol key, void *val)
{
  MPlist *action = mplist ();

  mplist_add (action, Msymbol, name);
  mplist_add (action, key, val);
  mplist_add (actions, Mplist, action);
  m17n_object_unref (action);
}

/* Return a list of all candidates of the Nth segment.  The return
   value is a plist whose elements are plists who contains at most 5
   candidates.  */

static MPlist *
make_candidate_list (AnthyContext *context, int n)
{
  MPlist *plist = mplist (), *pl;
  int i;
  char buf[1024];
  struct anthy_segment_stat ss;
  MText *mt;
  
  anthy_get_segment_stat (context->ac, n, &ss);
  for (i = 0, pl = mplist (); i < ss.nr_candidate; i++)
    {
      anthy_get_segment (context->ac, n, i, buf, sizeof (buf));
      mconv_rebind_buffer (context->converter,
			   (unsigned char *) buf, strlen (buf));
      mt = mconv_decode (context->converter, mtext ());
      mtext_put_prop (mt, 0, mtext_len (mt), Msegment, (void *) (n + 1));
      mplist_add (pl, Mtext, mt);
      m17n_object_unref (mt);
      if (i % 5 == 4)
	{
	  mplist_add (plist, Mplist, pl);
	  m17n_object_unref (pl);
	  pl = mplist ();
	}
    }
  if (mplist_key (pl) != Mnil)
    mplist_add (plist, Mplist, pl);
  m17n_object_unref (pl);
  return plist;
}

MPlist *
init (MPlist *args)
{
  MInputContext *ic = mplist_value (args);
  AnthyContext *context;

  if (! initialized++)
    {
      anthy_init ();
      Manthy = msymbol (" anthy");
      Msegment = msymbol (" segment");
    }
  context = new_context (ic);
  if (context)
    mplist_push (ic->plist, Manthy, context);
  return NULL;
}

MPlist *
fini (MPlist *args)
{
  MInputContext *ic = mplist_value (args);
  AnthyContext *context = get_context (ic);

  if (context)
    free_context (context);
  return NULL;
}

MPlist *
convert (MPlist *args)
{
  MInputContext *ic = mplist_value (args);
  AnthyContext *context = get_context (ic);
  struct anthy_conv_stat cs;
  MPlist *action, *actions;
  int i;
  unsigned char buf[1024];

  if (! context)
    return NULL;

  mconv_rebind_buffer (context->converter, buf, sizeof (buf));
  mconv_encode (context->converter, ic->preedit);
  buf[context->converter->nbytes] = '\0';
  anthy_set_string (context->ac, (char *) buf);
  anthy_get_stat (context->ac, &cs);
  allocate_candidate_numbers (context, cs.nr_segment);

  actions = mplist ();
  add_action (actions, msymbol ("move"), Msymbol, msymbol ("@<"));
  add_action (actions, msymbol ("delete"), Msymbol, msymbol ("@>"));
  for (i = 0; i < cs.nr_segment; i++)
    {
      context->candidate_numbers[i] = 0;
      if (i == 1)
	add_action (actions, msymbol ("mark"), Msymbol, msymbol ("@anthy"));
      action = make_candidate_list (context, i);
      mplist_add (actions, Mplist, action);
      m17n_object_unref (action);
    }
  if (cs.nr_segment > 1)
    add_action (actions, msymbol ("move"), Msymbol, msymbol ("@anthy"));

  return actions;
}

MPlist *
change (MPlist *args)
{
  MInputContext *ic = mplist_value (args);
  AnthyContext *context = get_context (ic);
  int segment;

  if (! context)
    return NULL;
  if (! ic->candidate_list || ic->cursor_pos == 0)
    return NULL;
  segment = (int) mtext_get_prop (ic->preedit, ic->cursor_pos - 1, Msegment);
  if (segment == 0)
    return NULL;
  segment--;
  context->candidate_numbers[segment] = ic->candidate_index;
  return NULL;
}

MPlist *
resize (MPlist *args)
{
  MInputContext *ic = mplist_value (args);
  AnthyContext *context = get_context (ic);
  struct anthy_conv_stat cs;
  MSymbol shorten;
  int segment;
  MPlist *actions, *action;
  int i;

  if (! context)
    return NULL;
  if (! ic->candidate_list || ic->cursor_pos == 0)
    return NULL;
  segment = (int) mtext_get_prop (ic->preedit, ic->cursor_pos - 1, Msegment);
  if (segment == 0)
    return NULL;
  segment--;
  args = mplist_next (args);
  shorten = mplist_value (args);
  anthy_resize_segment (context->ac, segment, shorten == Mt ? -1 : 1);
  anthy_get_stat (context->ac, &cs);
  allocate_candidate_numbers (context, cs.nr_segment);

  actions = mplist ();
  if (segment == 0)
    add_action (actions, msymbol ("move"), Msymbol, msymbol ("@<"));
  else
    add_action (actions, msymbol ("move"), Msymbol, msymbol ("@["));
  add_action (actions, msymbol ("delete"), Msymbol, msymbol ("@>"));
  for (i = segment; i < cs.nr_segment; i++)
    {
      context->candidate_numbers[i] = 0;
      if (i == segment + 1)
	add_action (actions, msymbol ("mark"), Msymbol, msymbol ("@anthy"));
      action = make_candidate_list (context, i);
      mplist_add (actions, Mplist, action);
      m17n_object_unref (action);
    }
  if (segment + 1 < cs.nr_segment)
    add_action (actions, msymbol ("move"), Msymbol, msymbol ("@anthy"));
  return actions;
}

MPlist *
commit (MPlist *args)
{
  MInputContext *ic = mplist_value (args);
  AnthyContext *context = get_context (ic);
  struct anthy_conv_stat cs;
  int i;

  if (! context)
    return NULL;
  anthy_get_stat (context->ac, &cs);
  for (i = 0; i < cs.nr_segment; i++)
    anthy_commit_segment (context->ac, i, context->candidate_numbers[i]);
  return NULL;
}

#else  /* not HAVE_ANTHY */

MPlist *convert (MPlist *args) { return NULL; }
MPlist *change (MPlist *args) { return NULL; }
MPlist *resize (MPlist *args) { return NULL; }
MPlist *commit (MPlist *args) { return NULL; }

#endif /* not HAVE_ANTHY */
#endif /* not FOR_DOXYGEN */