(delete_surrounding_text): Clear cache if necessary.

[m17n/m17n-lib.git] / src / input.c

/* input.c -- input method module.
   Copyright (C) 2003, 2004, 2005
     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., 59 Temple Place, Suite 330, Boston, MA
   02111-1307, USA.  */

/***en
    @addtogroup m17nInputMethod
    @brief API for Input method.

    An input method is an object to enable inputting various
    characters.  An input method is identified by a pair of symbols,
    LANGUAGE and NAME.  This pair decides a input method driver of the
    input method.  An input method driver is a set of functions for
    handling the input method.  There are two kinds of input methods;
    internal one and foreign one.

    <ul>
    <li> Internal Input Method

    An internal input method has non @c Mnil LANGUAGE, and the body is
    defined in the m17n database by the tag <Minput_method, LANGUAGE,
    NAME>.  For this kind of input methods, the m17n library uses two
    predefined input method drivers, one for CUI use and the other for
    GUI use.  Those driver utilize the input processing engine
    provided by the m17n library itself.  The m17n database may
    provides an input method that is not only for a specific language.
    The database uses @c Mt as LANGUAGE of such an input method.

    An internal input method accepts an input key which is a symbol
    associated with an input event.  As there is no way for the @c
    m17n @c library to know how input events are represented in an
    application program, an application programmer have to convert an
    input event to an input key by himself.  See the documentation of
    the function minput_event_to_key () for the detail.

    <li> Foreign Input Method

    A foreign input method has @c Mnil LANGUAGE, and the body is
    defined in an external resources (e.g. XIM of X Window System).
    For this kind of input methods, the symbol NAME must have a
    property of key @c Minput_driver, and the value must be a pointer
    to an input method driver.  Therefore, by preparing a proper
    driver, any kind of input method can be treated in the framework
    of the @c m17n @c library.

    For convenience, the m17n-X library provides an input method
    driver that enables the input style of OverTheSpot for XIM, and
    stores @c Minput_driver property of the symbol @c Mxim with a
    pointer to the driver.  See the documentation of m17n GUI API for
    the detail.

    </ul>

    PROCESSING FLOW

    The typical processing flow of handling an input method is: 

     @li open an input method
     @li create an input context for the input method
     @li filter an input key
     @li look up a produced text in the input context  */

/*=*/
/***ja
    @addtogroup m17nInputMethod
    @brief ÆþÎϥ᥽¥Ã¥ÉÍÑAPI.

    ÆþÎϥ᥽¥Ã¥É¤Ï¿ÍͤÊʸ»ú¤òÆþÎϤ¹¤ë¤¿¤á¤Î¥ª¥Ö¥¸¥§¥¯¥È¤Ç¤¢¤ë¡£
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    <ul> 
    <li> ÆâÉôÆþÎϥ᥽¥Ã¥É

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    <Minput_method, LANGUAGE, NAME> 
    ¤È¤¤¤¦¥¿¥°¤òÉÕ¤±¤ÆÄêµÁ¤µ¤ì¤Æ¤¤¤ë¡£
    ¤³¤Î¼ï¤ÎÆþÎϥ᥽¥Ã¥É¤ËÂФ·¤Æ¡¢m17n ¥é¥¤¥Ö¥é¥ê¤Ç¤Ï
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    m17n ¥Ç¡¼¥¿¥Ù¡¼¥¹¤Ë¤Ï¡¢ÆÃÄê¤Î¸À¸ìÀìÍѤǤʤ¤ÆþÎϥ᥽¥Ã¥É¤òÄêµÁ¤¹¤ë¤³¤È¤â¤Ç¤­¡¢
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    ÆâÉôÆþÎϥ᥽¥Ã¥É¤Ï¡¢¥æ¡¼¥¶¤ÎÆþÎÏ¥¤¥Ù¥ó¥È¤ËÂбþ¤·¤¿¥·¥ó¥Ü¥ë¤Ç¤¢¤ëÆþÎÏ¥­¡¼¤ò¼õ¤±¼è¤ë¡£
    @c m17n @c ¥é¥¤¥Ö¥é¥ê ¤ÏÆþÎÏ¥¤¥Ù¥ó¥È¤¬¥¢¥×¥ê¥±¡¼¥·¥ç¥ó¥×¥í¥°¥é¥à¤Ç¤É¤¦É½¸½¤µ¤ì¤Æ¤¤¤ë¤«¤òÃΤ뤳¤È¤¬¤Ç¤­¤Ê¤¤¤Î¤Ç¡¢
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    ¾ÜºÙ¤Ë¤Ä¤¤¤Æ¤Ï´Ø¿ô minput_event_to_key () ¤ÎÀâÌÀ¤ò»²¾È¡£

    <li> ³°ÉôÆþÎϥ᥽¥Ã¥É

    ³°ÉôÆþÎϥ᥽¥Ã¥É¤È¤Ï LANGUAGE ¤¬ @c Mnil ¤Î¤â¤Î¤Ç¤¢¤ê¡¢¤½¤ÎËÜÂΤϳ°Éô¤Î¥ê¥½¡¼¥¹¤È¤·¤ÆÄêµÁ¤µ¤ì¤ë¡£
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    ¤³¤Î¼ï¤ÎÆþÎϥ᥽¥Ã¥É¤Ç¤Ï¡¢¥·¥ó¥Ü¥ë NAME ¤Ï@c Minput_driver 
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    ÍøÊØÀ­¤Î´ÑÅÀ¤«¤é¡¢m17n X ¥é¥¤¥Ö¥é¥ê¤Ï XIM ¤Î OverTheSpot 
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    @c Minput_driver ¥×¥í¥Ñ¥Æ¥£¤ÎÃͤȤ·¤Æ¤½¤Î¥É¥é¥¤¥Ð¤Ø¤Î¥Ý¥¤¥ó¥¿¤òÊÝ»ý¤·¤Æ¤¤¤ë¡£
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    </ul> 

    ½èÍý¤Îή¤ì

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    @li ÆþÎϥ᥽¥Ã¥É¤Î¥ª¡¼¥×¥ó
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    @li ÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È¤Ç¤ÎÀ¸À®¥Æ¥­¥¹¥È¤Î¸¡º÷     */

/*=*/

#if !defined (FOR_DOXYGEN) || defined (DOXYGEN_INTERNAL_MODULE)
/*** @addtogroup m17nInternal
     @{ */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <dirent.h>
#include <sys/stat.h>
#include <unistd.h>

#include "config.h"

#ifdef HAVE_DLFCN_H
#include <dlfcn.h>
#endif

#include "m17n-gui.h"
#include "m17n-misc.h"
#include "internal.h"
#include "mtext.h"
#include "input.h"
#include "symbol.h"
#include "plist.h"
#include "database.h"
#include "charset.h"

static int mdebug_mask = MDEBUG_INPUT;

static MSymbol Minput_method;

/** Symbols to load an input method data.  */
static MSymbol Mtitle, Mmacro, Mmodule, Mstate, Minclude;

/** Symbols for actions.  */
static MSymbol Minsert, Mdelete, Mmark, Mmove, Mpushback, Mundo, Mcall, Mshift;
static MSymbol Mselect, Mshow, Mhide, Mcommit, Munhandle;
static MSymbol Mset, Madd, Msub, Mmul, Mdiv, Mequal, Mless, Mgreater;
static MSymbol M_candidates;

static MSymbol Mcandidate_list, Mcandidate_index;

static MSymbol Minit, Mfini;

/** Symbols for variables.  */
static MSymbol Mcandidates_group_size, Mcandidates_charset;

/** Symbols for key events.  */
static MSymbol one_char_symbol[256];

static MSymbol M_key_alias;

static MSymbol M_description, M_command, M_variable;

/** Structure to hold a map.  */

struct MIMMap
{
  /** List of actions to take when we reach the map.  In a root map,
      the actions are executed only when there's no more key.  */
  MPlist *map_actions;

  /** List of deeper maps.  If NULL, this is a terminal map.  */
  MPlist *submaps;

  /** List of actions to take when we leave the map successfully.  In
      a root map, the actions are executed only when none of submaps
      handle the current key.  */
  MPlist *branch_actions;
};

typedef MPlist *(*MIMExternalFunc) (MPlist *plist);

typedef struct
{
  void *handle;
  MPlist *func_list;            /* function name vs (MIMExternalFunc *) */
} MIMExternalModule;

struct MIMState
{
  M17NObject control;

  /** Name of the state.  */
  MSymbol name;

  /** Title of the state, or NULL.  */
  MText *title;

  /** Key translation map of the state.  Built by merging all maps of
      branches.  */
  MIMMap *map;
};

/* Lookup keys KEY1,2,3 in the nested plist PLIST, and return the
   value.  */

static MPlist *
lookup_nested_list (MPlist *plist, MSymbol key1, MSymbol key2, MSymbol key3)
{
  MSymbol key[3];
  int i;

  key[0] = key1, key[1] = key2, key[2] = key3;
  for (i = 0; i < 3; i++)
    {
      plist = mplist_find_by_value (plist, key[i]);
      if (! plist)
        return NULL;
      plist = MPLIST_NEXT (plist);
      plist = MPLIST_PLIST (plist);
    }
  return plist;
}

/* Set VAL for keys KEY1,2,3 in the nested plist PLIST.  */

static MPlist *
set_nested_list (MPlist *plist, MSymbol key1, MSymbol key2, MSymbol key3,
                 MPlist *val)
{
  MSymbol key[3];
  int i;
  MPlist *pl;

  key[0] = key1, key[1] = key2, key[2] = key3;
  for (i = 0; i < 3; i++)
    {
      pl = mplist_find_by_value (plist, key[i]);
      if (pl)
        {
          pl = MPLIST_NEXT (pl);
          plist = MPLIST_PLIST (pl);
        }
      else
        {
          pl = mplist_add (plist, Msymbol, key[i]);
          plist = mplist ();
          pl = mplist_add (pl, Mplist, plist);
          M17N_OBJECT_UNREF (plist);
        }
    }
  mplist_set (pl, Mplist, val);
  M17N_OBJECT_UNREF (val);
  return pl;
}

/* Parse PLIST as a value of nested list and return an adjusted list.

   PLIST has this form;
     (symbol:command
      plist:(symbol:KEY
             [ mtext:DESCRIPTION | symbol:nil ]
             ;; The remaining elements are checked CHECK_FUNC.
             ...)
      plist:(symbol:KEY
             [ mtext:DESCRIPTION | symbol:nil ]
             ;; The remaining elements are checked CHECK_FUNC.
             ...)
      ...)

   GLOBAL is a global list.  If a description text is missing, it is
   extracted from GLOBAL.

   The return value is a plist of this format:
     (symbol:KEY
      plist:([ mtext:DESCRIPTION | symbol:nil ]
             ...)
      symbol:KEY
      plist:([ mtext:DESCRIPTION | symbol:nil ]
             ...)
      ...)

   PLIST itself is unref-ed.  */

static MPlist *
parse_nested_list_value (MPlist *plist, MPlist *global, MSymbol key,
                         int (*check_func) (MPlist *))
{
  MPlist *val, *pl, *p, *p0;

  val = mplist ();
  if (! MPLIST_PLIST_P (plist))
    {
      M17N_OBJECT_UNREF (plist);
      return val;
    }
  pl = MPLIST_PLIST (plist);
  if (! MPLIST_SYMBOL_P (pl)
      || MPLIST_SYMBOL (pl) != key)
    {
      M17N_OBJECT_UNREF (plist);
      return val;
    }

  MPLIST_DO (pl, MPLIST_NEXT (pl))
    {
      MSymbol name;
      MPlist *global_def;

      if (! MPLIST_PLIST_P (pl))
        continue;
      p = MPLIST_PLIST (pl);
      if (! MPLIST_SYMBOL_P (p))
        continue;
      name = MPLIST_SYMBOL (p);
      p = MPLIST_NEXT (p);
      if (MPLIST_TAIL_P (p))
        {
          if (! global)
            continue;
          global_def = mplist_find_by_value (global, name);
          if (! global_def)
            continue;
          global_def = MPLIST_PLIST (MPLIST_NEXT (global_def));
          mplist__conc (p, global_def);
          global = NULL;
        }
      p0 = MPLIST_NEXT (p);
      if (MPLIST_TAIL_P (p0))
        {
          if (! global)
            continue;
          global_def = mplist_find_by_value (global, name);
          if (! global_def)
            continue;
          global_def = MPLIST_PLIST (MPLIST_NEXT (global_def));
          global_def = MPLIST_NEXT (global_def);
          if (MPLIST_TAIL_P (global_def))
            continue;
          mplist__conc (p0, global_def);
        }
      if ((*check_func) (p0) < 0)
        continue;
      mplist_add (val, Msymbol, name);
      mplist_add (val, Mplist, p);
    }

  M17N_OBJECT_UNREF (plist);
  return val;
}

static MPlist *variable_list, *command_list;
static int check_variable_list (MPlist *plist);
static int check_command_list (MPlist *plist);
static MPlist *load_partial_im_info (MSymbol language, MSymbol name,
                                     MSymbol extra, MSymbol key);

static MPlist *
get_nested_list (MSymbol language, MSymbol name, MSymbol extra, MSymbol key)
{
  MPlist *total_list;
  int (*check_func) (MPlist *);
  MPlist *plist, *global;

  if (key == M_variable)
    {
      if (! variable_list)
        variable_list = mplist ();
      total_list = variable_list;
      check_func = check_variable_list;
    }
  else
    {
      if (! command_list)
        command_list = mplist ();
      total_list = command_list;
      check_func = check_command_list;
    }

  if (MPLIST_TAIL_P (total_list))
    {
      plist = load_partial_im_info (Mt, Mnil, key, key);
      if (plist)
        global = parse_nested_list_value (plist, NULL, key, check_func);
      else
        global = mplist ();
      set_nested_list (total_list, Mt, Mnil, key, global);
    }
  else
    global = lookup_nested_list (total_list, Mt, Mnil, key);

  if (name == Mnil)
    return global;

  plist = lookup_nested_list (total_list, language, name, extra);
  if (plist)
    return plist;

  plist = load_partial_im_info (language, name, extra, key);
  if (plist)
    plist = parse_nested_list_value (plist, global, key, check_func);
  else
    plist = mplist ();
  set_nested_list (total_list, language, name, extra, plist);
  return plist;
}

static int
marker_code (MSymbol sym)
{
  char *name;

  if (sym == Mnil)
    return -1;
  name = MSYMBOL_NAME (sym);
  return ((name[0] == '@'
           && ((name[1] >= '0' && name[1] <= '9')
               || name[1] == '<' || name[1] == '>'
               || name[1] == '=' || name[1] == '+' || name[1] == '-'
               || name[1] == '[' || name[1] == ']'
               || name[1] == '@')
           && name[2] == '\0')
          ? name[1] : -1);
}


static MPlist *
resolve_variable (MInputContextInfo *ic_info, MSymbol var)
{
  MPlist *p;

  MPLIST_DO (p, ic_info->vars)
    {
      if (MPLIST_SYMBOL (p) == var)
        break;
      p = MPLIST_NEXT (p);
    }
  if (MPLIST_TAIL_P (p))
    {
      p = ic_info->vars;
      mplist_push (p, Minteger, (void *) 0);
      mplist_push (p, Msymbol, var);
    }
  return (MPLIST_NEXT (p));
}

static MText *
get_surrounding_text (MInputContext *ic, int len)
{
  MText *mt = NULL;

  mplist_push (ic->plist, Minteger, (void *) len);
  minput__callback (ic, Minput_get_surrounding_text);
  if (MPLIST_MTEXT_P (ic->plist))
    {
      mt = MPLIST_MTEXT (ic->plist);
      mplist_pop (ic->plist);
    }
  return mt;
}

static void
delete_surrounding_text (MInputContext *ic, int pos)
{
  MInputContextInfo *ic_info = (MInputContextInfo *) ic->info;

  mplist_push (ic->plist, Minteger, (void *) pos);
  minput__callback (ic, Minput_delete_surrounding_text);
  mplist_pop (ic->plist);
  if (pos < 0)
    M17N_OBJECT_UNREF (ic_info->preceding_text);
  else if (pos > 0)
    M17N_OBJECT_UNREF (ic_info->following_text);
}

static int
get_preceding_char (MInputContext *ic, int pos)
{
  MInputContextInfo *ic_info = (MInputContextInfo *) ic->info;
  MText *mt;
  int len;

  if (ic_info->preceding_text)
    {
      len = mtext_nchars (ic_info->preceding_text);
      if (pos <= len)
        return mtext_ref_char (ic_info->preceding_text, len - pos);
    }
  mt = get_surrounding_text (ic, - pos);
  if (! mt)
    return -1;
  len = mtext_nchars (mt);
  if (ic_info->preceding_text)
    {
      if (mtext_nchars (ic_info->preceding_text) < len)
        {
          M17N_OBJECT_UNREF (ic_info->preceding_text);
          ic_info->preceding_text = mt;
        }
    }
  else
    ic_info->preceding_text = mt;
  if (pos > len)
    return -1;
  return mtext_ref_char (ic_info->preceding_text, len - pos);
}

static int
get_following_char (MInputContext *ic, int pos)
{
  MInputContextInfo *ic_info = (MInputContextInfo *) ic->info;
  MText *mt;
  int len;

  if (ic_info->following_text)
    {
      len = mtext_nchars (ic_info->following_text);
      if (pos <= len)
        return mtext_ref_char (ic_info->following_text, pos - 1);
    }
  mt = get_surrounding_text (ic, pos);
  if (! mt)
    return -1;
  len = mtext_nchars (mt);
  if (ic_info->following_text)
    {
      if (mtext_nchars (ic_info->following_text) < len)
        {
          M17N_OBJECT_UNREF (ic_info->following_text);
          ic_info->following_text = mt;
        }
    }
  else
    ic_info->following_text = mt;
  if (pos > len)
    return -1;
  return mtext_ref_char (ic_info->following_text, pos - 1);
}

static int
surrounding_pos (MSymbol sym)
{
  char *name;

  if (sym == Mnil)
    return 0;
  name = MSYMBOL_NAME (sym);
  if ((name[1] == '-' || name[1] == '+')
      && name[2] >= '1' && name[2] <= '9')
    return (name[1] == '-' ? - atoi (name + 2) : atoi (name + 2));
  return 0;
}

static int
integer_value (MInputContext *ic, MPlist *arg, MPlist **value, int surrounding)
{
  MInputContextInfo *ic_info = (MInputContextInfo *) ic->info;
  int code;
  MText *preedit = ic->preedit;
  int len = mtext_nchars (preedit);

  if (value)
    *value = NULL;
  if (MPLIST_INTEGER_P (arg))
    return MPLIST_INTEGER (arg);
  if (surrounding
      && (surrounding = surrounding_pos (MPLIST_SYMBOL (arg))) != 0)
    return (surrounding < 0
            ? get_preceding_char (ic, - surrounding)
            : get_following_char (ic, surrounding));
  code = marker_code (MPLIST_SYMBOL (arg));
  if (code < 0)
    {
      MPlist *val = resolve_variable (ic_info, MPLIST_SYMBOL (arg));

      if (value)
        *value = val;
      return (MPLIST_INTEGER_P (val) ? MPLIST_INTEGER (val) : 0);
    }
  if (code == '@')
    return ic_info->key_head;
  if (code >= '0' && code <= '9')
    code -= '0';
  else if (code == '=')
    code = ic->cursor_pos;
  else if (code == '-' || code == '[')
    code = ic->cursor_pos - 1;
  else if (code == '+' || code == ']')
    code = ic->cursor_pos + 1;
  else if (code == '<')
    code = 0;
  else if (code == '>')
    code = len;
  return (code >= 0 && code < len ? mtext_ref_char (preedit, code) : -1);
}


/* Parse PLIST as an action list.  PLIST should have this form:
      PLIST ::= ( (ACTION-NAME ACTION-ARG *) *).
   Return 0 if successfully parsed, otherwise return -1.  */

static int
parse_action_list (MPlist *plist, MPlist *macros)
{
  MPLIST_DO (plist, plist)
    {
      if (MPLIST_MTEXT_P (plist))
        {
          /* This is a short form of (insert MTEXT).  */
          /* if (mtext_nchars (MPLIST_MTEXT (plist)) == 0)
             MERROR (MERROR_IM, -1); */
        }
      else if (MPLIST_PLIST_P (plist)
               && (MPLIST_MTEXT_P (MPLIST_PLIST (plist))
                   || MPLIST_PLIST_P (MPLIST_PLIST (plist))))
        {
          MPlist *pl;

          /* This is a short form of (insert (GROUPS *)).  */
          MPLIST_DO (pl, MPLIST_PLIST (plist))
            {
              if (MPLIST_PLIST_P (pl))
                {
                  MPlist *elt;

                  MPLIST_DO (elt, MPLIST_PLIST (pl))
                    if (! MPLIST_MTEXT_P (elt)
                        || mtext_nchars (MPLIST_MTEXT (elt)) == 0)
                      MERROR (MERROR_IM, -1);
                }
              else
                {
                  if (! MPLIST_MTEXT_P (pl)
                      || mtext_nchars (MPLIST_MTEXT (pl)) == 0)
                    MERROR (MERROR_IM, -1);
                }
            }
        }
      else if (MPLIST_INTEGER_P (plist))
        {
          int c = MPLIST_INTEGER (plist);

          if (c < 0 || c > MCHAR_MAX)
            MERROR (MERROR_IM, -1);
        }
      else if (MPLIST_PLIST_P (plist)
               && MPLIST_SYMBOL_P (MPLIST_PLIST (plist)))
        {
          MPlist *pl = MPLIST_PLIST (plist);
          MSymbol action_name = MPLIST_SYMBOL (pl);

          pl = MPLIST_NEXT (pl);

          if (action_name == Minsert)
            {
              if (MPLIST_MTEXT_P (pl))
                {
                  if (mtext_nchars (MPLIST_MTEXT (pl)) == 0)
                    MERROR (MERROR_IM, -1);
                }
              else if (MPLIST_PLIST_P (pl))
                {
                  MPLIST_DO (pl, pl)
                    {
                      if (MPLIST_PLIST_P (pl))
                        {
                          MPlist *elt;

                          MPLIST_DO (elt, MPLIST_PLIST (pl))
                            if (! MPLIST_MTEXT_P (elt)
                                || mtext_nchars (MPLIST_MTEXT (elt)) == 0)
                              MERROR (MERROR_IM, -1);
                        }
                      else
                        {
                          if (! MPLIST_MTEXT_P (pl)
                              || mtext_nchars (MPLIST_MTEXT (pl)) == 0)
                            MERROR (MERROR_IM, -1);
                        }
                    }
                }
              else if (! MPLIST_SYMBOL_P (pl))
                MERROR (MERROR_IM, -1); 
            }
          else if (action_name == Mselect
                   || action_name == Mdelete
                   || action_name == Mmove)
            {
              if (! MPLIST_SYMBOL_P (pl)
                  && ! MPLIST_INTEGER_P (pl))
                MERROR (MERROR_IM, -1);
            }
          else if (action_name == Mmark
                   || action_name == Mcall
                   || action_name == Mshift)
            {
              if (! MPLIST_SYMBOL_P (pl))
                MERROR (MERROR_IM, -1);
            }
          else if (action_name == Mundo)
            {
              if (! MPLIST_TAIL_P (pl))
                {
                  if (! MPLIST_SYMBOL_P (pl)
                      && (! MPLIST_INTEGER_P (pl)
                          || MPLIST_INTEGER (pl) == 0))
                    MERROR (MERROR_IM, -1);                 
                }
            }
          else if (action_name == Mpushback)
            {
              if (MPLIST_MTEXT_P (pl))
                {
                  MText *mt = MPLIST_MTEXT (pl);

                  if (mtext_nchars (mt) != mtext_nbytes (mt))
                    MERROR (MERROR_IM, -1);                 
                }
              else if (MPLIST_PLIST_P (pl))
                {
                  MPlist *p;

                  MPLIST_DO (p, MPLIST_PLIST (pl))
                    if (! MPLIST_SYMBOL_P (p))
                      MERROR (MERROR_IM, -1);
                }
              else if (! MPLIST_INTEGER_P (pl))
                MERROR (MERROR_IM, -1);
            }
          else if (action_name == Mset || action_name == Madd
                   || action_name == Msub || action_name == Mmul
                   || action_name == Mdiv)
            {
              if (! (MPLIST_SYMBOL_P (pl)
                     && (MPLIST_INTEGER_P (MPLIST_NEXT (pl))
                         || MPLIST_SYMBOL_P (MPLIST_NEXT (pl)))))
                MERROR (MERROR_IM, -1);
            }
          else if (action_name == Mequal || action_name == Mless
                   || action_name == Mgreater)
            {
              if (! ((MPLIST_INTEGER_P (pl) || MPLIST_SYMBOL_P (pl))
                     && (MPLIST_INTEGER_P (MPLIST_NEXT (pl))
                         || MPLIST_SYMBOL_P (MPLIST_NEXT (pl)))))
                MERROR (MERROR_IM, -1);
              pl = MPLIST_NEXT (MPLIST_NEXT (pl));
              if (! MPLIST_PLIST_P (pl))
                MERROR (MERROR_IM, -1);
              if (parse_action_list (MPLIST_PLIST (pl), macros) < 0)
                MERROR (MERROR_IM, -1);
              pl = MPLIST_NEXT (pl);
              if (MPLIST_PLIST_P (pl)
                  && parse_action_list (MPLIST_PLIST (pl), macros) < 0)
                MERROR (MERROR_IM, -1);
            }
          else if (action_name == Mshow || action_name == Mhide
                   || action_name == Mcommit || action_name == Munhandle)
            ;
          else if (! macros || ! mplist_get (macros, action_name))
            MERROR (MERROR_IM, -1);
        }
      else
        MERROR (MERROR_IM, -1);
    }

  return 0;
}

static MPlist *
resolve_command (MSymbol language, MSymbol name, MSymbol command)
{
  MPlist *plist = get_nested_list (language, name, Mnil, M_command);

  if (! plist
      || ! (plist = mplist_get (plist, command)))
    return NULL;
  plist = MPLIST_NEXT (plist);
  if (! MPLIST_PLIST_P (plist))
    return NULL;
  return plist;
}



/* Load a translation into MAP from PLIST.
   PLIST has this form:
      PLIST ::= ( KEYSEQ MAP-ACTION * )  */

static int
load_translation (MIMMap *map, MPlist *keylist, MPlist *map_actions,
                  MPlist *branch_actions, MPlist *macros)
{
  MSymbol *keyseq;
  int len, i;

  if (MPLIST_MTEXT_P (keylist))
    {
      MText *mt = MPLIST_MTEXT (keylist);

      len = mtext_nchars (mt);
      if (len == 0 || len != mtext_nbytes (mt))
        MERROR (MERROR_IM, -1);
      keyseq = (MSymbol *) alloca (sizeof (MSymbol) * len);
      for (i = 0; i < len; i++)
        keyseq[i] = one_char_symbol[MTEXT_DATA (mt)[i]];
    }
  else if (MPLIST_PLIST_P (keylist))
    {
      MPlist *elt = MPLIST_PLIST (keylist);
          
      len = MPLIST_LENGTH (elt);
      if (len == 0)
        MERROR (MERROR_IM, -1);
      keyseq = (MSymbol *) alloca (sizeof (int) * len);
      for (i = 0; i < len; i++, elt = MPLIST_NEXT (elt))
        {
          if (MPLIST_INTEGER_P (elt))
            {
              int c = MPLIST_INTEGER (elt);

              if (c < 0 || c >= 0x100)
                MERROR (MERROR_IM, -1);
              keyseq[i] = one_char_symbol[c];
            }
          else if (MPLIST_SYMBOL_P (elt))
            keyseq[i] = MPLIST_SYMBOL (elt);
          else
            MERROR (MERROR_IM, -1);
        }
    }
  else
    MERROR (MERROR_IM, -1);

  for (i = 0; i < len; i++)
    {
      MIMMap *deeper = NULL;

      if (map->submaps)
        deeper = mplist_get (map->submaps, keyseq[i]);
      else
        map->submaps = mplist ();
      if (! deeper)
        {
          /* Fixme: It is better to make all deeper maps at once.  */
          MSTRUCT_CALLOC (deeper, MERROR_IM);
          mplist_put (map->submaps, keyseq[i], deeper);
        }
      map = deeper;
    }

  /* We reach a terminal map.  */
  if (map->map_actions
      || map->branch_actions)
    /* This map is already defined.  We avoid overriding it.  */
    return 0;

  if (! MPLIST_TAIL_P (map_actions))
    {
      if (parse_action_list (map_actions, macros) < 0)
        MERROR (MERROR_IM, -1);
      map->map_actions = map_actions;
    }
  if (branch_actions)
    {
      map->branch_actions = branch_actions;
      M17N_OBJECT_REF (branch_actions);
    }

  return 0;
}

/* Load a branch from PLIST into MAP.  PLIST has this form:
      PLIST ::= ( MAP-NAME BRANCH-ACTION * )
   MAPS is a plist of raw maps.
   STATE is the current state.  */

static int
load_branch (MPlist *plist, MPlist *maps, MIMMap *map,
             MSymbol language, MSymbol name, MPlist *macros)
{
  MSymbol map_name;
  MPlist *branch_actions;

  if (! MPLIST_SYMBOL_P (plist))
    MERROR (MERROR_IM, -1);
  map_name = MPLIST_SYMBOL (plist);
  plist = MPLIST_NEXT (plist);
  if (MPLIST_TAIL_P (plist))
    branch_actions = NULL;
  else if (parse_action_list (plist, macros) < 0)
    MERROR (MERROR_IM, -1);
  else
    branch_actions = plist;
  if (map_name == Mnil)
    {
      map->branch_actions = branch_actions;
      if (branch_actions)
        M17N_OBJECT_REF (branch_actions);
    }
  else if (map_name == Mt)
    {
      map->map_actions = branch_actions;
      if (branch_actions)
        M17N_OBJECT_REF (branch_actions);
    }
  else if ((plist = (MPlist *) mplist_get (maps, map_name)))
    {
      MPLIST_DO (plist, plist)
        {
          MPlist *keylist, *map_actions;

          if (! MPLIST_PLIST_P (plist))
            MERROR (MERROR_IM, -1);
          keylist = MPLIST_PLIST (plist);
          map_actions = MPLIST_NEXT (keylist);
          if (MPLIST_SYMBOL_P (keylist))
            {
              MSymbol command = MPLIST_SYMBOL (keylist);
              MPlist *pl = resolve_command (language, name, command);

              if (! pl)
                return -1;
              MPLIST_DO (pl, pl)
                if (load_translation (map, pl, map_actions, branch_actions,
                                      macros) < 0)
                  MERROR (MERROR_IM, -1);
            }
          else
            if (load_translation (map, keylist, map_actions, branch_actions,
                                  macros) < 0)
              MERROR (MERROR_IM, -1);
        }
    }

  return 0;
}

/* Load a macro from PLIST into MACROS.
   PLIST has this from:
      PLIST ::= ( MACRO-NAME ACTION * )
   MACROS is a plist of macro names vs action list.  */
static int
load_macros (MPlist *plist, MPlist *macros)
{
  MSymbol name; 

  if (! MPLIST_SYMBOL_P (plist))
    MERROR (MERROR_IM, -1);
  name = MPLIST_SYMBOL (plist);
  plist = MPLIST_NEXT (plist);
  if (MPLIST_TAIL_P (plist)
      || parse_action_list (plist, macros) < 0)
    MERROR (MERROR_IM, -1);
  mplist_put (macros, name, plist);
  M17N_OBJECT_REF (plist);
  return 0;
}

/* Load an external module from PLIST into EXTERNALS.
   PLIST has this form:
      PLIST ::= ( MODULE-NAME FUNCTION * )
   EXTERNALS is a plist of MODULE-NAME vs (MIMExternalModule *).  */

static int
load_external_module (MPlist *plist, MPlist *externals)
{
  void *handle;
  MSymbol module;
  char *module_file;
  MIMExternalModule *external;
  MPlist *func_list;
  void *func;

  if (MPLIST_MTEXT_P (plist))
    module = msymbol ((char *) MTEXT_DATA (MPLIST_MTEXT (plist)));
  else if (MPLIST_SYMBOL_P (plist))
    module = MPLIST_SYMBOL (plist);
  module_file = alloca (strlen (MSYMBOL_NAME (module))
                        + strlen (DLOPEN_SHLIB_EXT) + 1);
  sprintf (module_file, "%s%s", MSYMBOL_NAME (module), DLOPEN_SHLIB_EXT);

  handle = dlopen (module_file, RTLD_NOW);
  if (! handle)
    {
      fprintf (stderr, "%s\n", dlerror ());
      MERROR (MERROR_IM, -1);
    }
  func_list = mplist ();
  MPLIST_DO (plist, MPLIST_NEXT (plist))
    {
      if (! MPLIST_SYMBOL_P (plist))
        MERROR_GOTO (MERROR_IM, err_label);
      func = dlsym (handle, MSYMBOL_NAME (MPLIST_SYMBOL (plist)));
      if (! func)
        MERROR_GOTO (MERROR_IM, err_label);
      mplist_add (func_list, MPLIST_SYMBOL (plist), func);
    }

  MSTRUCT_MALLOC (external, MERROR_IM);
  external->handle = handle;
  external->func_list = func_list;
  mplist_add (externals, module, external);
  return 0;

 err_label:
  dlclose (handle);
  M17N_OBJECT_UNREF (func_list);
  return -1;
}

static void
free_map (MIMMap *map, int top)
{
  MPlist *plist;

  if (top)
    M17N_OBJECT_UNREF (map->map_actions);
  if (map->submaps)
    {
      MPLIST_DO (plist, map->submaps)
        free_map ((MIMMap *) MPLIST_VAL (plist), 0);
      M17N_OBJECT_UNREF (map->submaps);
    }
  M17N_OBJECT_UNREF (map->branch_actions);
  free (map);
}

static void
free_state (void *object)
{
  MIMState *state = object;

  if (state->title)
    M17N_OBJECT_UNREF (state->title);
  if (state->map)
    free_map (state->map, 1);
  free (state);
}

/** Load a state from PLIST into a newly allocated state object.
    PLIST has this form:
      PLIST ::= ( STATE-NAME STATE-TITLE ? BRANCH * )
      BRANCH ::= ( MAP-NAME BRANCH-ACTION * )
   MAPS is a plist of defined maps.
   Return the state object.  */

static MIMState *
load_state (MPlist *plist, MPlist *maps, MSymbol language, MSymbol name,
            MPlist *macros)
{
  MIMState *state;

  if (! MPLIST_SYMBOL_P (plist))
    MERROR (MERROR_IM, NULL);
  M17N_OBJECT (state, free_state, MERROR_IM);
  state->name = MPLIST_SYMBOL (plist);
  plist = MPLIST_NEXT (plist);
  if (MPLIST_MTEXT_P (plist))
    {
      state->title = MPLIST_MTEXT (plist);
      mtext_put_prop (state->title, 0, mtext_nchars (state->title),
                      Mlanguage, language);
      M17N_OBJECT_REF (state->title);
      plist = MPLIST_NEXT (plist);
    }
  MSTRUCT_CALLOC (state->map, MERROR_IM);
  MPLIST_DO (plist, plist)
    if (! MPLIST_PLIST_P (plist)
        || load_branch (MPLIST_PLIST (plist), maps, state->map, language, name,
                        macros) < 0)
      MERROR (MERROR_IM, NULL);
  return state;
}


static MPlist *im_info_list;

static void
free_im_info (MInputMethodInfo *im_info)
{
  MPlist *plist;

  if (im_info->title)
    M17N_OBJECT_UNREF (im_info->title);
  if (im_info->states)
    {
      MPLIST_DO (plist, im_info->states)
        {
          MIMState *state = (MIMState *) MPLIST_VAL (plist);

          M17N_OBJECT_UNREF (state);
        }
      M17N_OBJECT_UNREF (im_info->states);
    }

  if (im_info->macros)
    {
      MPLIST_DO (plist, im_info->macros)
        M17N_OBJECT_UNREF (MPLIST_VAL (plist)); 
      M17N_OBJECT_UNREF (im_info->macros);
    }

  if (im_info->externals)
    {
      MPLIST_DO (plist, im_info->externals)
        {
          MIMExternalModule *external = MPLIST_VAL (plist);

          dlclose (external->handle);
          M17N_OBJECT_UNREF (external->func_list);
          free (external);
          MPLIST_KEY (plist) = Mt;
        }
      M17N_OBJECT_UNREF (im_info->externals);
    }
  if (im_info->maps)
    {
      MPLIST_DO (plist, im_info->maps)
        {
          MPlist *p = MPLIST_PLIST (plist);

          M17N_OBJECT_UNREF (p);
        }
      M17N_OBJECT_UNREF (im_info->maps);
    }

  free (im_info);
}

static MInputMethodInfo *get_im_info (MSymbol language, MSymbol name,
                                      MSymbol extra);

static MInputMethodInfo *
get_im_info_by_tags (MPlist *plist)
{
  MSymbol tag[3];
  int i;

  for (i = 0; i < 3 && MPLIST_SYMBOL_P (plist);
       i++, plist = MPLIST_NEXT (plist))
    tag[i] = MPLIST_SYMBOL (plist);
  if (i < 2)
    return NULL;
  for (; i < 3; i++)
    tag[i] = Mnil;
  return get_im_info (tag[0], tag[1], tag[2]);
}

/* Load an input method from PLIST into IM_INTO, and return it.  */

static MInputMethodInfo *
load_im_info (MSymbol language, MSymbol name, MPlist *plist)
{
  MInputMethodInfo *im_info;
  MText *title = NULL;
  MPlist *maps = NULL;
  MPlist *states = NULL;
  MPlist *externals = NULL;
  MPlist *macros = NULL;
  MPlist *elt;

  MSTRUCT_CALLOC (im_info, MERROR_IM);

  while (MPLIST_PLIST_P (plist))
    {
      elt = MPLIST_PLIST (plist);
      if (! MPLIST_SYMBOL_P (elt))
        MERROR_GOTO (MERROR_IM, err);
      if (MPLIST_SYMBOL (elt) == Mtitle)
        {
          elt = MPLIST_NEXT (elt);
          if (! MPLIST_MTEXT_P (elt))
            MERROR_GOTO (MERROR_IM, err);
          im_info->title = title = MPLIST_MTEXT (elt);
          M17N_OBJECT_REF (title);
        }
      else if (MPLIST_SYMBOL (elt) == Mmap)
        {
          MPlist *pl = mplist__from_alist (MPLIST_NEXT (elt));

          if (! pl)
            MERROR_GOTO (MERROR_IM, err);
          if (! maps)
            im_info->maps = maps = pl;
          else
            maps = mplist__conc (maps, pl);
        }
      else if (MPLIST_SYMBOL (elt) == Mmacro)
        {
          if (! macros)
            im_info->macros = macros = mplist ();
          MPLIST_DO (elt, MPLIST_NEXT (elt))
            {
              if (! MPLIST_PLIST_P (elt)
                  || load_macros (MPLIST_PLIST (elt), macros) < 0)
                MERROR_GOTO (MERROR_IM, err);
            }
        }
      else if (MPLIST_SYMBOL (elt) == Mmodule)
        {
          if (! externals)
            im_info->externals = externals = mplist ();
          MPLIST_DO (elt, MPLIST_NEXT (elt))
            {
              if (! MPLIST_PLIST_P (elt)
                  || load_external_module (MPLIST_PLIST (elt), externals) < 0)
                MERROR_GOTO (MERROR_IM, err);
            }
        }
      else if (MPLIST_SYMBOL (elt) == Mstate)
        {
          MPLIST_DO (elt, MPLIST_NEXT (elt))
            {
              MIMState *state;

              if (! MPLIST_PLIST_P (elt))
                MERROR_GOTO (MERROR_IM, err);
              state = load_state (MPLIST_PLIST (elt), maps, language, name,
                                  macros);
              if (! state)
                MERROR_GOTO (MERROR_IM, err);
              if (! states)
                im_info->states = states = mplist ();
              mplist_put (states, state->name, state);
            }
        }
      else if (MPLIST_SYMBOL (elt) == Minclude)
        {
          /* elt ::= include (tag1 tag2 ...) key item ... */
          MSymbol key;
          MInputMethodInfo *temp;
          MPlist *pl, *p;

          elt = MPLIST_NEXT (elt);
          if (! MPLIST_PLIST_P (elt))
            MERROR_GOTO (MERROR_IM, err);
          temp = get_im_info_by_tags (MPLIST_PLIST (elt));
          if (! temp)
            MERROR_GOTO (MERROR_IM, err);
          elt = MPLIST_NEXT (elt);
          if (! MPLIST_SYMBOL_P (elt))
            MERROR_GOTO (MERROR_IM, err);
          key = MPLIST_SYMBOL (elt);
          elt = MPLIST_NEXT (elt);
          if (key == Mmap)
            {
              if (! maps)
                im_info->maps = maps = mplist ();
              MPLIST_DO (pl, temp->maps)
                {
                  p = MPLIST_VAL (pl);
                  MPLIST_ADD_PLIST (maps, MPLIST_KEY (pl), p);
                  M17N_OBJECT_REF (p);
                }
            }
          else if (key == Mmacro)
            {
              if (! macros)
                im_info->macros = macros = mplist ();
              MPLIST_DO (pl, temp->macros)
                {
                  p = MPLIST_VAL (pl);
                  MPLIST_ADD_PLIST (macros, MPLIST_KEY (pl), p);
                  M17N_OBJECT_REF (p);
                }
            }
          else if (key == Mstate)
            {
              if (! states)
                im_info->states = states = mplist ();
              MPLIST_DO (pl, temp->states)
                {
                  MIMState *state = MPLIST_VAL (pl);

                  mplist_add (states, MPLIST_KEY (pl), state);
                  M17N_OBJECT_REF (state);
                }
            }
          else
            MERROR_GOTO (MERROR_IM, err);
        }
      plist = MPLIST_NEXT (plist);
    }

  if (! states)
    goto err;
  if (! title && name)
    im_info->title
      = title = mtext_from_data (MSYMBOL_NAME (name), MSYMBOL_NAMELEN (name),
                                 MTEXT_FORMAT_US_ASCII);
  return im_info;

 err:
  free_im_info (im_info);
  return NULL;
}

\f

static int take_action_list (MInputContext *ic, MPlist *action_list);
static void preedit_commit (MInputContext *ic);

static void
shift_state (MInputContext *ic, MSymbol state_name)
{
  MInputMethodInfo *im_info = (MInputMethodInfo *) ic->im->info;
  MInputContextInfo *ic_info = (MInputContextInfo *) ic->info;
  MIMState *orig_state = ic_info->state, *state;

  /* Find a state to shift to.  If not found, shift to the initial
     state.  */
  if (state_name == Mt)
    {
      if (! ic_info->prev_state)
        return;
      state = ic_info->prev_state;
    }
  else
    {
      state = (MIMState *) mplist_get (im_info->states, state_name);
      if (! state)
        state = (MIMState *) MPLIST_VAL (im_info->states);
    }

  MDEBUG_PRINT1 ("\n  [IM] (shift %s)", MSYMBOL_NAME (state->name));

  /* Enter the new state.  */
  ic_info->state = state;
  ic_info->map = state->map;
  ic_info->state_key_head = ic_info->key_head;
  if (state == (MIMState *) MPLIST_VAL (im_info->states))
    /* We have shifted to the initial state.  */
    preedit_commit (ic);
  mtext_cpy (ic_info->preedit_saved, ic->preedit);
  ic_info->state_pos = ic->cursor_pos;
  if (state != orig_state )
    {
      if (state == (MIMState *) MPLIST_VAL (im_info->states))
        ic_info->prev_state = NULL;
      else
        ic_info->prev_state = orig_state;

      if (state->title)
        ic->status = state->title;
      else
        ic->status = im_info->title;
      ic->status_changed = 1;
      if (ic_info->map == ic_info->state->map
          && ic_info->map->map_actions)
        {
          MDEBUG_PRINT (" init-actions:");
          take_action_list (ic, ic_info->map->map_actions);
        }
    }
}

/* Find a candidate group that contains a candidate number INDEX from
   PLIST.  Set START_INDEX to the first candidate number of the group,
   END_INDEX to the last candidate number plus 1, GROUP_INDEX to the
   candidate group number if they are non-NULL.  If INDEX is -1, find
   the last candidate group.  */

static MPlist *
find_candidates_group (MPlist *plist, int index,
                       int *start_index, int *end_index, int *group_index)
{
  int i = 0, gidx = 0, len;

  MPLIST_DO (plist, plist)
    {
      if (MPLIST_MTEXT_P (plist))
        len = mtext_nchars (MPLIST_MTEXT (plist));
      else
        len = mplist_length (MPLIST_PLIST (plist));
      if (index < 0 ? MPLIST_TAIL_P (MPLIST_NEXT (plist))
          : i + len > index)
        {
          if (start_index)
            *start_index = i;
          if (end_index)
            *end_index = i + len;
          if (group_index)
            *group_index = gidx;
          return plist;
        }
      i += len;
      gidx++;
    }
  return NULL;
}

static void
preedit_insert (MInputContext *ic, int pos, MText *mt, int c)
{
  MInputContextInfo *ic_info = ((MInputContext *) ic)->info;
  MPlist *markers;
  int nchars = mt ? mtext_nchars (mt) : 1;

  if (mt)
    mtext_ins (ic->preedit, pos, mt);
  else
    mtext_ins_char (ic->preedit, pos, c, 1);
  MPLIST_DO (markers, ic_info->markers)
    if (MPLIST_INTEGER (markers) > pos)
      MPLIST_VAL (markers) = (void *) (MPLIST_INTEGER (markers) + nchars);
  if (ic->cursor_pos >= pos)
    ic->cursor_pos += nchars;
  ic->preedit_changed = 1;
}


static void
preedit_delete (MInputContext *ic, int from, int to)
{
  MInputContextInfo *ic_info = ((MInputContext *) ic)->info;
  MPlist *markers;

  mtext_del (ic->preedit, from, to);
  MPLIST_DO (markers, ic_info->markers)
    {
      if (MPLIST_INTEGER (markers) > to)
        MPLIST_VAL (markers)
          = (void *) (MPLIST_INTEGER (markers) - (to - from));
      else if (MPLIST_INTEGER (markers) > from);
        MPLIST_VAL (markers) = (void *) from;
    }
  if (ic->cursor_pos >= to)
    ic->cursor_pos -= to - from;
  else if (ic->cursor_pos > from)
    ic->cursor_pos = from;
  ic->preedit_changed = 1;
}

static void
preedit_commit (MInputContext *ic)
{
  MInputContextInfo *ic_info = (MInputContextInfo *) ic->info;
  int preedit_len = mtext_nchars (ic->preedit);

  if (preedit_len > 0)
    {
      MPlist *p;

      mtext_put_prop_values (ic->preedit, 0, mtext_nchars (ic->preedit),
                             Mcandidate_list, NULL, 0);
      mtext_put_prop_values (ic->preedit, 0, mtext_nchars (ic->preedit),
                             Mcandidate_index, NULL, 0);
      mtext_cat (ic->produced, ic->preedit);
      if ((mdebug__flag & mdebug_mask)
          && mtext_nchars (ic->produced) > 0)
        {
          int i;

          MDEBUG_PRINT (" (produced");
          for (i = 0; i < mtext_nchars (ic->produced); i++)
            MDEBUG_PRINT1 (" U+%04X", mtext_ref_char (ic->produced, i));
          MDEBUG_PRINT (")");
        }
      mtext_reset (ic->preedit);
      mtext_reset (ic_info->preedit_saved);
      MPLIST_DO (p, ic_info->markers)
        MPLIST_VAL (p) = 0;
      ic->cursor_pos = ic_info->state_pos = 0;
      ic->preedit_changed = 1;
    }
  if (ic->candidate_list)
    {
      M17N_OBJECT_UNREF (ic->candidate_list);
      ic->candidate_list = NULL;
      ic->candidate_show = 0;
      ic->candidates_changed = MINPUT_CANDIDATES_LIST_CHANGED;
      if (ic->candidate_show)
        {
          ic->candidate_show = 0;
          ic->candidates_changed |= MINPUT_CANDIDATES_SHOW_CHANGED;
        }
    }

  memmove (ic_info->keys, ic_info->keys + ic_info->key_head,
           sizeof (int) * (ic_info->used - ic_info->key_head));
  ic_info->used -= ic_info->key_head;
  ic_info->state_key_head = ic_info->key_head = 0;
}

static int
new_index (MInputContext *ic, int current, int limit, MSymbol sym, MText *mt)
{
  int code = marker_code (sym);

  if (mt && (code == '[' || code == ']'))
    {
      int pos = current;

      if (code == '[' && current > 0)
        {
          if (mtext_prop_range (mt, Mcandidate_list, pos - 1, &pos, NULL, 1)
              && pos > 0)
            current = pos;
        }
      else if (code == ']' && current < mtext_nchars (mt))
        {
          if (mtext_prop_range (mt, Mcandidate_list, pos, NULL, &pos, 1))
            current = pos;
        }
      return current;
    }
  if (code >= 0)
    return (code == '<' ? 0
            : code == '>' ? limit
            : code == '-' ? current - 1
            : code == '+' ? current + 1
            : code == '=' ? current
            : code - '0' > limit ? limit
            : code - '0');
  if (! ic)  
    return 0;
  return (int) mplist_get (((MInputContextInfo *) ic->info)->markers, sym);
}

static void
update_candidate (MInputContext *ic, MTextProperty *prop, int idx)
{
  int from = mtext_property_start (prop);
  int to = mtext_property_end (prop);
  int start;
  MPlist *candidate_list = mtext_property_value (prop);
  MPlist *group = find_candidates_group (candidate_list, idx, &start,
                                         NULL, NULL);
  int ingroup_index = idx - start;
  MText *mt;

  preedit_delete (ic, from, to);
  if (MPLIST_MTEXT_P (group))
    {
      mt = MPLIST_MTEXT (group);
      preedit_insert (ic, from, NULL, mtext_ref_char (mt, ingroup_index));
      to = from + 1;
    }
  else
    {
      int i;
      MPlist *plist;

      for (i = 0, plist = MPLIST_PLIST (group); i < ingroup_index;
           i++, plist = MPLIST_NEXT (plist));
      mt = MPLIST_MTEXT (plist);
      preedit_insert (ic, from, mt, 0);
      to = from + mtext_nchars (mt);
    }
  mtext_put_prop (ic->preedit, from, to, Mcandidate_list, candidate_list);
  mtext_put_prop (ic->preedit, from, to, Mcandidate_index, (void *) idx);
  ic->cursor_pos = to;
}

static MCharset *
get_select_charset (MInputContextInfo * ic_info)
{
  MPlist *plist = resolve_variable (ic_info, Mcandidates_charset);
  MSymbol sym;

  if (! MPLIST_VAL (plist))
    return NULL;
  sym = MPLIST_SYMBOL (plist);
  if (sym == Mnil)
    return NULL;
  return MCHARSET (sym);
}

static MPlist *
adjust_candidates (MPlist *plist, MCharset *charset)
{
  MPlist *pl;

  /* plist ::= MTEXT ... | PLIST ... */
  plist = mplist_copy (plist);
  if (MPLIST_MTEXT_P (plist))
    {
      pl = plist;
      while (! MPLIST_TAIL_P (pl))
        {
          /* pl ::= MTEXT ... */
          MText *mt = MPLIST_MTEXT (pl);
          int mt_copied = 0;
          int i, c;

          for (i = mtext_nchars (mt) - 1; i >= 0; i--)
            {
              c = mtext_ref_char (mt, i);
              if (ENCODE_CHAR (charset, c) == MCHAR_INVALID_CODE)
                {
                  if (! mt_copied)
                    {
                      mt = mtext_dup (mt);
                      mplist_set (pl, Mtext, mt);
                      M17N_OBJECT_UNREF (mt);
                      mt_copied = 1;
                    }
                  mtext_del (mt, i, i + 1);
                }
            }
          if (mtext_len (mt) > 0)
            pl = MPLIST_NEXT (pl);
          else
            {
              mplist_pop (pl);
              M17N_OBJECT_UNREF (mt);
            }
        }
    }
  else                          /* MPLIST_PLIST_P (plist) */
    {
      pl = plist;
      while (! MPLIST_TAIL_P (pl))
        {
          /* pl ::= (MTEXT ...) ... */
          MPlist *p = MPLIST_PLIST (pl);
          int p_copied = 0;
          /* p ::= MTEXT ... */
          MPlist *p0 = p;
          int n = 0;

          while (! MPLIST_TAIL_P (p0))
            {
              MText *mt = MPLIST_MTEXT (p0);
              int i, c;

              for (i = mtext_nchars (mt) - 1; i >= 0; i--)
                {
                  c = mtext_ref_char (mt, i);
                  if (ENCODE_CHAR (charset, c) == MCHAR_INVALID_CODE)
                    break;
                }
              if (i < 0)
                {
                  p0 = MPLIST_NEXT (p0);
                  n++;
                }
              else
                {
                  if (! p_copied)
                    {
                      p = mplist_copy (p);
                      mplist_set (pl, Mplist, p);
                      M17N_OBJECT_UNREF (p);
                      p_copied = 1;
                      p0 = p;
                      while (n-- > 0)
                        p0 = MPLIST_NEXT (p0);
                    }     
                  mplist_pop (p0);
                  M17N_OBJECT_UNREF (mt);
                }
            }
          if (! MPLIST_TAIL_P (p))
            pl = MPLIST_NEXT (pl);
          else
            {
              mplist_pop (pl);
              M17N_OBJECT_UNREF (p);
            }
        }
    }
  if (MPLIST_TAIL_P (plist))
    {
      M17N_OBJECT_UNREF (plist);
      return NULL;
    }      
  return plist;
}

static MPlist *
get_candidate_list (MInputContextInfo *ic_info, MPlist *args)
{
  MCharset *charset = get_select_charset (ic_info);
  MPlist *plist;
  int column;
  int i, len;

  plist = resolve_variable (ic_info, Mcandidates_group_size);
  column = MPLIST_INTEGER (plist);

  plist = MPLIST_PLIST (args);
  if (charset)
    {
      if (! (plist = adjust_candidates (plist, charset)))
        return NULL;
    }
  else
    M17N_OBJECT_REF (plist);

  if (column > 0)
    {
      if (MPLIST_MTEXT_P (plist))
        {
          MText *mt = MPLIST_MTEXT (plist);
          MPlist *next = MPLIST_NEXT (plist);

          if (MPLIST_TAIL_P (next))
            M17N_OBJECT_REF (mt);
          else
            {
              mt = mtext_dup (mt);
              while (! MPLIST_TAIL_P (next))
                {
                  mt = mtext_cat (mt, MPLIST_MTEXT (next));
                  next = MPLIST_NEXT (next);
                }
            }
          M17N_OBJECT_UNREF (plist);
          plist = mplist ();
          len = mtext_nchars (mt);
          if (len <= column)
            mplist_add (plist, Mtext, mt);
          else
            {
              for (i = 0; i < len; i += column)
                {
                  int to = (i + column < len ? i + column : len);
                  MText *sub = mtext_copy (mtext (), 0, mt, i, to);
                                                       
                  mplist_add (plist, Mtext, sub);
                  M17N_OBJECT_UNREF (sub);
                }
            }
          M17N_OBJECT_UNREF (mt);
        }
      else              /* MPLIST_PLIST_P (plist) */
        {
          MPlist *pl = MPLIST_PLIST (plist), *p;
          MPlist *next = MPLIST_NEXT (plist);
          int j;

          if (MPLIST_TAIL_P (next))
            M17N_OBJECT_REF (pl);
          else
            {
              pl = mplist_copy (pl);
              while (! MPLIST_TAIL_P (next))
                {
                  p = mplist_copy (MPLIST_PLIST (next));
                  pl = mplist__conc (pl, p);
                  M17N_OBJECT_UNREF (p);
                  next = MPLIST_NEXT (next);
                }
            }
          M17N_OBJECT_UNREF (plist);
          plist = mplist ();
          len = mplist_length (pl);
          if (len <= column)
            mplist_add (plist, Mplist, pl);
          else
            {
              MPlist *p0 = pl;

              for (i = 0; i < len; i += column)
                {
                  p = mplist ();
                  mplist_add (plist, Mplist, p);
                  M17N_OBJECT_UNREF (p);
                  for (j = 0; j < column && i + j < len; j++)
                    {
                      p = mplist_add (p, Mtext, MPLIST_VAL (p0));
                      p0 = MPLIST_NEXT (p0);
                    }
                }
            }
          M17N_OBJECT_UNREF (pl);
        }
    }

  return plist;
}


static MPlist *
regularize_action (MPlist *action_list)
{
  MPlist *action = NULL;
  MSymbol name;
  MPlist *args;

  if (MPLIST_PLIST_P (action_list))
    {
      action = MPLIST_PLIST (action_list);
      if (MPLIST_SYMBOL_P (action))
        {
          name = MPLIST_SYMBOL (action);
          args = MPLIST_NEXT (action);
          if (name == Minsert
              && MPLIST_PLIST_P (args))
            mplist_set (action, Msymbol, M_candidates);
        }
      else if (MPLIST_MTEXT_P (action) || MPLIST_PLIST_P (action))
        {
          action = mplist ();
          mplist_push (action, Mplist, MPLIST_VAL (action_list));
          mplist_push (action, Msymbol, M_candidates);
          mplist_set (action_list, Mplist, action);
          M17N_OBJECT_UNREF (action);
        }
    }
  else if (MPLIST_MTEXT_P (action_list) || MPLIST_INTEGER_P (action_list))
    {
      action = mplist ();
      mplist_push (action, MPLIST_KEY (action_list), MPLIST_VAL (action_list));
      mplist_push (action, Msymbol, Minsert);
      mplist_set (action_list, Mplist, action);
      M17N_OBJECT_UNREF (action);
    }
  return action;
}

static int
take_action_list (MInputContext *ic, MPlist *action_list)
{
  MInputContextInfo *ic_info = (MInputContextInfo *) ic->info;
  MPlist *candidate_list = ic->candidate_list;
  int candidate_index = ic->candidate_index;
  int candidate_show = ic->candidate_show;
  MTextProperty *prop;

  MPLIST_DO (action_list, action_list)
    {
      MPlist *action = regularize_action (action_list);
      MSymbol name;
      MPlist *args;

      if (! action)
        continue;
      name = MPLIST_SYMBOL (action);
      args = MPLIST_NEXT (action);

      MDEBUG_PRINT1 (" %s", MSYMBOL_NAME (name));
      if (name == Minsert)
        {
          if (MPLIST_SYMBOL_P (args))
            {
              args = resolve_variable (ic_info, MPLIST_SYMBOL (args));
              if (! MPLIST_MTEXT_P (args) && ! MPLIST_INTEGER_P (args))
                continue;
            }
          if (MPLIST_MTEXT_P (args))
            preedit_insert (ic, ic->cursor_pos, MPLIST_MTEXT (args), 0);
          else                  /* MPLIST_INTEGER_P (args)) */
            preedit_insert (ic, ic->cursor_pos, NULL, MPLIST_INTEGER (args));
        }
      else if (name == M_candidates)
        {
          MPlist *plist = get_candidate_list (ic_info, args);
          int len;

          if (! plist)
            continue;
          if (MPLIST_MTEXT_P (plist))
            {
              preedit_insert (ic, ic->cursor_pos, NULL,
                              mtext_ref_char (MPLIST_MTEXT (plist), 0));
              len = 1;
            }
          else
            {
              MText * mt = MPLIST_MTEXT (MPLIST_PLIST (plist));

              preedit_insert (ic, ic->cursor_pos, mt, 0);
              len = mtext_nchars (mt);
            }
          mtext_put_prop (ic->preedit,
                          ic->cursor_pos - len, ic->cursor_pos,
                          Mcandidate_list, plist);
          mtext_put_prop (ic->preedit,
                          ic->cursor_pos - len, ic->cursor_pos,
                          Mcandidate_index, (void *) 0);
          M17N_OBJECT_UNREF (plist);
        }
      else if (name == Mselect)
        {
          int start, end;
          int code, idx, gindex;
          int pos = ic->cursor_pos;
          MPlist *group;

          if (pos == 0
              || ! (prop = mtext_get_property (ic->preedit, pos - 1,
                                               Mcandidate_list)))
            continue;
          if (MPLIST_SYMBOL_P (args))
            {
              code = marker_code (MPLIST_SYMBOL (args));
              if (code < 0)
                continue;
            }
          else
            code = -1;
          idx = (int) mtext_get_prop (ic->preedit, pos - 1, Mcandidate_index);
          group = find_candidates_group (mtext_property_value (prop), idx,
                                         &start, &end, &gindex);

          if (code != '[' && code != ']')
            {
              idx = (start
                     + (code >= 0
                        ? new_index (NULL, ic->candidate_index - start,
                                     end - start - 1, MPLIST_SYMBOL (args),
                                     NULL)
                        : MPLIST_INTEGER (args)));
              if (idx < 0)
                {
                  find_candidates_group (mtext_property_value (prop), -1,
                                         NULL, &end, NULL);
                  idx = end - 1;
                }
              else if (idx >= end
                       && MPLIST_TAIL_P (MPLIST_NEXT (group)))
                idx = 0;
            }
          else
            {
              int ingroup_index = idx - start;
              int len;

              group = mtext_property_value (prop);
              len = mplist_length (group);
              if (code == '[')
                {
                  gindex--;
                  if (gindex < 0)
                    gindex = len - 1;;
                }
              else
                {
                  gindex++;
                  if (gindex >= len)
                    gindex = 0;
                }
              for (idx = 0; gindex > 0; gindex--, group = MPLIST_NEXT (group))
                idx += (MPLIST_MTEXT_P (group)
                        ? mtext_nchars (MPLIST_MTEXT (group))
                        : mplist_length (MPLIST_PLIST (group)));
              len = (MPLIST_MTEXT_P (group)
                     ? mtext_nchars (MPLIST_MTEXT (group))
                     : mplist_length (MPLIST_PLIST (group)));
              if (ingroup_index >= len)
                ingroup_index = len - 1;
              idx += ingroup_index;
            }
          update_candidate (ic, prop, idx);
        }
      else if (name == Mshow)
        ic->candidate_show = 1;
      else if (name == Mhide)
        ic->candidate_show = 0;
      else if (name == Mdelete)
        {
          int len = mtext_nchars (ic->preedit);
          int pos;
          int to;

          if (MPLIST_SYMBOL_P (args)
              && (pos = surrounding_pos (MPLIST_SYMBOL (args))) != 0)
            {
              delete_surrounding_text (ic, pos);
            }
          else
            {
              to = (MPLIST_SYMBOL_P (args)
                    ? new_index (ic, ic->cursor_pos, len, MPLIST_SYMBOL (args),
                                 ic->preedit)
                    : MPLIST_INTEGER (args));
              if (to < 0)
                to = 0;
              else if (to > len)
                to = len;
              if (to < ic->cursor_pos)
                preedit_delete (ic, to, ic->cursor_pos);
              else if (to > ic->cursor_pos)
                preedit_delete (ic, ic->cursor_pos, to);
            }
        }
      else if (name == Mmove)
        {
          int len = mtext_nchars (ic->preedit);
          int pos
            = (MPLIST_SYMBOL_P (args)
               ? new_index (ic, ic->cursor_pos, len, MPLIST_SYMBOL (args),
                            ic->preedit)
               : MPLIST_INTEGER (args));

          if (pos < 0)
            pos = 0;
          else if (pos > len)
            pos = len;
          if (pos != ic->cursor_pos)
            {
              ic->cursor_pos = pos;
              ic->preedit_changed = 1;
            }
        }
      else if (name == Mmark)
        {
          int code = marker_code (MPLIST_SYMBOL (args));

          if (code < 0)
            mplist_put (ic_info->markers, MPLIST_SYMBOL (args),
                        (void *) ic->cursor_pos);
        }
      else if (name == Mpushback)
        {
          if (MPLIST_INTEGER_P (args))
            {
              int num = MPLIST_INTEGER (args);

              if (num > 0)
                ic_info->key_head -= num;
              else
                ic_info->key_head = num;
              if (ic_info->key_head > ic_info->used)
                ic_info->key_head = ic_info->used;
            }
          else if (MPLIST_MTEXT_P (args))
            {
              MText *mt = MPLIST_MTEXT (args);
              int i, len = mtext_nchars (mt);
              MSymbol key;

              ic_info->key_head--;
              for (i = 0; i < len; i++)
                {
                  key = one_char_symbol[MTEXT_DATA (mt)[i]];
                  if (ic_info->key_head + i < ic_info->used)
                    ic_info->keys[ic_info->key_head + i] = key;
                  else
                    MLIST_APPEND1 (ic_info, keys, key, MERROR_IM);
                }
            }
          else
            {
              MPlist *plist = MPLIST_PLIST (args), *pl;
              int i = 0;
              MSymbol key;

              ic_info->key_head--;

              MPLIST_DO (pl, plist)
                {
                  key = MPLIST_SYMBOL (pl);
                  if (ic_info->key_head < ic_info->used)
                    ic_info->keys[ic_info->key_head + i] = key;
                  else
                    MLIST_APPEND1 (ic_info, keys, key, MERROR_IM);
                  i++;
                }
            }
        }
      else if (name == Mcall)
        {
          MInputMethodInfo *im_info = (MInputMethodInfo *) ic->im->info;
          MIMExternalFunc func = NULL;
          MSymbol module, func_name;
          MPlist *func_args, *val;
          int ret = 0;

          module = MPLIST_SYMBOL (args);
          args = MPLIST_NEXT (args);
          func_name = MPLIST_SYMBOL (args);

          if (im_info->externals)
            {
              MIMExternalModule *external
                = (MIMExternalModule *) mplist_get (im_info->externals,
                                                    module);
              if (external)
                func = (MIMExternalFunc) mplist_get (external->func_list,
                                                     func_name);
            }
          if (! func)
            continue;
          func_args = mplist ();
          mplist_add (func_args, Mt, ic);
          MPLIST_DO (args, MPLIST_NEXT (args))
            {
              int code;

              if (MPLIST_KEY (args) == Msymbol
                  && MPLIST_KEY (args) != Mnil
                  && (code = marker_code (MPLIST_SYMBOL (args))) >= 0)
                {
                  code = new_index (ic, ic->cursor_pos, 
                                    mtext_nchars (ic->preedit),
                                    MPLIST_SYMBOL (args), ic->preedit);
                  mplist_add (func_args, Minteger, (void *) code);
                }
              else
                mplist_add (func_args, MPLIST_KEY (args), MPLIST_VAL (args));
            }
          val = (func) (func_args);
          M17N_OBJECT_UNREF (func_args);
          if (val && ! MPLIST_TAIL_P (val))
            ret = take_action_list (ic, val);
          M17N_OBJECT_UNREF (val);
          if (ret < 0)
            return ret;
        }
      else if (name == Mshift)
        {
          shift_state (ic, MPLIST_SYMBOL (args));
        }
      else if (name == Mundo)
        {
          int intarg = (MPLIST_TAIL_P (args)
                        ? ic_info->used - 2
                        : integer_value (ic, args, NULL, 0));

          mtext_reset (ic->preedit);
          mtext_reset (ic_info->preedit_saved);
          ic->cursor_pos = ic_info->state_pos = 0;
          ic_info->state_key_head = ic_info->key_head = 0;

          if (intarg < 0)
            ic_info->used += intarg;
          else
            ic_info->used = intarg;
          shift_state (ic, Mnil);
          break;
        }
      else if (name == Mset || name == Madd || name == Msub
               || name == Mmul || name == Mdiv)
        {
          MSymbol sym = MPLIST_SYMBOL (args);
          int val1, val2;
          MPlist *value;
          char *op;

          val1 = integer_value (ic, args, &value, 0);
          args = MPLIST_NEXT (args);
          val2 = integer_value (ic, args, NULL, 1);
          if (name == Mset)
            val1 = val2, op = "=";
          else if (name == Madd)
            val1 += val2, op = "+=";
          else if (name == Msub)
            val1 -= val2, op = "-=";
          else if (name == Mmul)
            val1 *= val2, op = "*=";
          else
            val1 /= val2, op = "/=";
          MDEBUG_PRINT3 ("(%s %s %d)", MSYMBOL_NAME (sym), op, val1);
          if (value)
            mplist_set (value, Minteger, (void *) val1);
        }
      else if (name == Mequal || name == Mless || name == Mgreater)
        {
          int val1, val2;
          MPlist *actions1, *actions2;
          int ret = 0;

          val1 = integer_value (ic, args, NULL, 1);
          args = MPLIST_NEXT (args);
          val2 = integer_value (ic, args, NULL, 1);
          args = MPLIST_NEXT (args);
          actions1 = MPLIST_PLIST (args);
          args = MPLIST_NEXT (args);
          if (MPLIST_TAIL_P (args))
            actions2 = NULL;
          else
            actions2 = MPLIST_PLIST (args);
          MDEBUG_PRINT3 ("(%d %s %d)? ", val1, MSYMBOL_NAME (name), val2);
          if (name == Mequal ? val1 == val2
              : name == Mless ? val1 < val2
              : val1 > val2)
            {
              MDEBUG_PRINT ("ok");
              ret = take_action_list (ic, actions1);
            }
          else
            {
              MDEBUG_PRINT ("no");
              if (actions2)
                ret = take_action_list (ic, actions2);
            }
          if (ret < 0)
            return ret;
        }
      else if (name == Mcommit)
        {
          preedit_commit (ic);
        }
      else if (name == Munhandle)
        {
          preedit_commit (ic);
          return -1;
        }
      else
        {
          MInputMethodInfo *im_info = (MInputMethodInfo *) ic->im->info;
          MPlist *actions;

          if (im_info->macros
              && (actions = mplist_get (im_info->macros, name)))
            {
              if (take_action_list (ic, actions) < 0)
                return -1;
            };
        }
    }

  prop = NULL;
  if (ic->candidate_list)
    {
      M17N_OBJECT_UNREF (ic->candidate_list);
      ic->candidate_list = NULL;
    }
  if (ic->cursor_pos > 0
      && (prop = mtext_get_property (ic->preedit, ic->cursor_pos - 1,
                                     Mcandidate_list)))
    {
      ic->candidate_list = mtext_property_value (prop);
      M17N_OBJECT_REF (ic->candidate_list);
      ic->candidate_index
        = (int) mtext_get_prop (ic->preedit, ic->cursor_pos - 1,
                                Mcandidate_index);
      ic->candidate_from = mtext_property_start (prop);
      ic->candidate_to = mtext_property_end (prop);
    }

  if (candidate_list != ic->candidate_list)
    ic->candidates_changed |= MINPUT_CANDIDATES_LIST_CHANGED;
  if (candidate_index != ic->candidate_index)
    ic->candidates_changed |= MINPUT_CANDIDATES_INDEX_CHANGED;
  if (candidate_show != ic->candidate_show)
    ic->candidates_changed |= MINPUT_CANDIDATES_SHOW_CHANGED;    
  return 0;
}


/* Handle the input key KEY in the current state and map specified in
   the input context IC.  If KEY is handled correctly, return 0.
   Otherwise, return -1.  */

static int
handle_key (MInputContext *ic)
{
  MInputMethodInfo *im_info = (MInputMethodInfo *) ic->im->info;
  MInputContextInfo *ic_info = (MInputContextInfo *) ic->info;
  MIMMap *map = ic_info->map;
  MIMMap *submap = NULL;
  MSymbol key = ic_info->keys[ic_info->key_head];
  int i;

  MDEBUG_PRINT2 ("  [IM] handle `%s' in state %s", 
                 MSYMBOL_NAME (key), MSYMBOL_NAME (ic_info->state->name));

  if (map->submaps)
    {
      MSymbol alias;

      submap = mplist_get (map->submaps, key);
      if (! submap && (alias = msymbol_get (key, M_key_alias)) != Mnil)
        submap = mplist_get (map->submaps, alias);
    }

  if (submap)
    {
      MDEBUG_PRINT (" submap-found");
      mtext_cpy (ic->preedit, ic_info->preedit_saved);
      ic->preedit_changed = 1;
      ic->cursor_pos = ic_info->state_pos;
      ic_info->key_head++;
      ic_info->map = map = submap;
      if (map->map_actions)
        {
          MDEBUG_PRINT (" map-actions:");
          if (take_action_list (ic, map->map_actions) < 0)
            {
              MDEBUG_PRINT ("\n");
              return -1;
            }
        }
      else if (map->submaps)
        {
          for (i = ic_info->state_key_head; i < ic_info->key_head; i++)
            {
              MSymbol key = ic_info->keys[i];
              char *name = msymbol_name (key);

              if (! name[0] || ! name[1])
                mtext_ins_char (ic->preedit, ic->cursor_pos++, name[0], 1);
            }
        }

      /* If this is the terminal map or we have shifted to another
         state, perform branch actions (if any).  */
      if (! map->submaps || map != ic_info->map)
        {
          if (map->branch_actions)
            {
              MDEBUG_PRINT (" branch-actions:");
              if (take_action_list (ic, map->branch_actions) < 0)
                {
                  MDEBUG_PRINT ("\n");
                  return -1;
                }
            }
          /* If MAP is still not the root map, shift to the current
             state.  */
          if (ic_info->map != ic_info->state->map)
            shift_state (ic, ic_info->state->name);
        }
    }
  else
    {
      /* MAP can not handle KEY.  */

      /* If MAP is the root map of the initial state, it means that
         the current input method can not handle KEY.  */
      if (map == ((MIMState *) MPLIST_VAL (im_info->states))->map)
        {
          MDEBUG_PRINT (" unhandled\n");
          return -1;
        }

      if (map != ic_info->state->map)
        {
          /* If MAP is not the root map... */
          /* If MAP has branch actions, perform them.  */
          if (map->branch_actions)
            {
              MDEBUG_PRINT (" branch-actions:");
              if (take_action_list (ic, map->branch_actions) < 0)
                {
                  MDEBUG_PRINT ("\n");
                  return -1;
                }
            }
          /* If MAP is still not the root map, shift to the current
             state. */
          if (ic_info->map != ic_info->state->map)
            {
              shift_state (ic, ic_info->state->name);
              /* If MAP has branch_actions, perform them.  */
              if (ic_info->map->branch_actions)
                {
                  MDEBUG_PRINT (" brank-actions:");
                  take_action_list (ic, ic_info->map->branch_actions);
                }
            }
        }
      else
        {
          /* MAP is the root map, perform branch actions (if any) or
             shift to the initial state.  */
          if (map->branch_actions)
            {
              MDEBUG_PRINT (" branch-actions:");
              if (take_action_list (ic, map->branch_actions) < 0)
                {
                  MDEBUG_PRINT ("\n");
                  return -1;
                }
            }
          else
            shift_state (ic, Mnil);
        }
    }
  MDEBUG_PRINT ("\n");
  return 0;
}

static void
reset_ic (MInputContext *ic, MSymbol ignore)
{
  MInputMethodInfo *im_info = (MInputMethodInfo *) ic->im->info;
  MInputContextInfo *ic_info = (MInputContextInfo *) ic->info;
  MText *status;

  MDEBUG_PRINT ("\n  [IM] reset\n");

  ic_info->state = (MIMState *) MPLIST_VAL (im_info->states);
  ic_info->prev_state = NULL;
  ic_info->map = ic_info->state->map;
  ic_info->state_key_head = ic_info->key_head;
  MLIST_RESET (ic_info);
  ic_info->key_unhandled = 0;

  if (mtext_nchars (ic->produced) > 0)
    mtext_reset (ic->produced);
  if (mtext_nchars (ic->preedit) > 0)
    {
      MPlist *plist;

      mtext_reset (ic->preedit);
      MPLIST_DO (plist, ic_info->markers)
        MPLIST_VAL (plist) = 0;
      ic->preedit_changed = 1;
    }
  if (ic->candidate_show)
    {
      ic->candidate_show = 0;
      ic->candidates_changed = MINPUT_CANDIDATES_SHOW_CHANGED;
      if (ic->candidate_list)
        {
          M17N_OBJECT_UNREF (ic->candidate_list);
          ic->candidate_list = NULL;
          ic->candidates_changed |= MINPUT_CANDIDATES_LIST_CHANGED;
        }
    }
  mtext_reset (ic_info->preedit_saved);
  ic_info->state_pos = ic->cursor_pos = 0;

  status = ic_info->state->title ? ic_info->state->title : im_info->title;
  if (ic->status != status)
    {
      ic->status = status;
      ic->status_changed = 1;
    }
}

static int
open_im (MInputMethod *im)
{
  MInputMethodInfo *im_info = get_im_info (im->language, im->name, Mnil);

  if (! im_info)
    MERROR (MERROR_IM, -1);
  im->info = im_info;
  im_info->im = im;
  return 0;
}

static void
close_im (MInputMethod *im)
{
  im->info = NULL;
}

static int
create_ic (MInputContext *ic)
{
  MInputMethod *im = ic->im;
  MInputMethodInfo *im_info = (MInputMethodInfo *) im->info;
  MInputContextInfo *ic_info;
  MPlist *plist;

  if (ic->info)
    ic_info = (MInputContextInfo *) ic->info;
  else
    {
      MSTRUCT_CALLOC (ic_info, MERROR_IM);
      ic->info = ic_info;
    }
  MLIST_INIT1 (ic_info, keys, 8);
  ic_info->markers = mplist ();
  ic_info->vars = mplist ();
  plist = get_nested_list (im->language, im->name, Mnil, M_variable);
  MPLIST_DO (plist, plist)
    {
      MSymbol var = MPLIST_SYMBOL (plist);
      MPlist *pl;

      plist = MPLIST_NEXT (plist);
      pl = MPLIST_PLIST (plist);
      pl = MPLIST_NEXT (pl);    /* Skip description.  */
      mplist_push (ic_info->vars, MPLIST_KEY (pl), MPLIST_VAL (pl));
      mplist_push (ic_info->vars, Msymbol, var);
    }

  ic_info->preedit_saved = mtext ();
  if (im_info->externals)
    {
      MPlist *func_args = mplist (), *plist;

      mplist_add (func_args, Mt, ic);
      MPLIST_DO (plist, im_info->externals)
        {
          MIMExternalModule *external = MPLIST_VAL (plist);
          MIMExternalFunc func
            = (MIMExternalFunc) mplist_get (external->func_list, Minit);

          if (func)
            (func) (func_args);
        }
      M17N_OBJECT_UNREF (func_args);
    }
  reset_ic (ic, Mnil);
  return 0;
}

static void
destroy_ic (MInputContext *ic)
{
  MInputMethodInfo *im_info = (MInputMethodInfo *) ic->im->info;
  MInputContextInfo *ic_info = (MInputContextInfo *) ic->info;

  if (im_info->externals)
    {
      MPlist *func_args = mplist (), *plist;

      mplist_add (func_args, Mt, ic);
      MPLIST_DO (plist, im_info->externals)
        {
          MIMExternalModule *external = MPLIST_VAL (plist);
          MIMExternalFunc func
            = (MIMExternalFunc) mplist_get (external->func_list, Mfini);

          if (func)
            (func) (func_args);
        }
      M17N_OBJECT_UNREF (func_args);
    }
  MLIST_FREE1 (ic_info, keys);
  M17N_OBJECT_UNREF (ic_info->preedit_saved);
  M17N_OBJECT_UNREF (ic_info->markers);
  M17N_OBJECT_UNREF (ic_info->vars);
  M17N_OBJECT_UNREF (ic_info->preceding_text);
  M17N_OBJECT_UNREF (ic_info->following_text);
  free (ic->info);
}


/** Handle the input key KEY in the current state and map of IC->info.
    If KEY is handled but no text is produced, return 0, otherwise
    return 1.

    Ignore ARG.  */

static int
filter (MInputContext *ic, MSymbol key, void *arg)
{
  MInputMethodInfo *im_info = (MInputMethodInfo *) ic->im->info;
  MInputContextInfo *ic_info = (MInputContextInfo *) ic->info;
  int i = 0;

  if (! ic_info->state)
    {
      ic_info->key_unhandled = 1;
      return 0;
    }
  mtext_reset (ic->produced);
  ic->status_changed = ic->preedit_changed = ic->candidates_changed = 0;
  M17N_OBJECT_UNREF (ic_info->preceding_text);
  M17N_OBJECT_UNREF (ic_info->following_text);
  MLIST_APPEND1 (ic_info, keys, key, MERROR_IM);
  ic_info->key_unhandled = 0;
  do {
    if (handle_key (ic) < 0)
      {
        /* KEY was not handled.  Delete it from the current key sequence.  */
        if (ic_info->used > 0)
          {
            memmove (ic_info->keys, ic_info->keys + 1,
                     sizeof (int) * (ic_info->used - 1));
            ic_info->used--;
          }
        /* This forces returning 1.  */
        ic_info->key_unhandled = 1;
        break;
      }
    if (i++ == 100)
      {
        mdebug_hook ();
        reset_ic (ic, Mnil);
        ic_info->key_unhandled = 1;
        break;
      }
    /* Break the loop if all keys were handled.  */
  } while (ic_info->key_head < ic_info->used);

  /* If the current map is the root of the initial state, we should
     produce any preedit text in ic->produced.  */
  if (ic_info->map == ((MIMState *) MPLIST_VAL (im_info->states))->map
      && mtext_nchars (ic->preedit) > 0)
    shift_state (ic, ((MIMState *) MPLIST_VAL (im_info->states))->name);

  if (mtext_nchars (ic->produced) > 0)
    {
      MSymbol lang = msymbol_get (ic->im->language, Mlanguage);

      if (lang != Mnil)
        mtext_put_prop (ic->produced, 0, mtext_nchars (ic->produced),
                        Mlanguage, ic->im->language);
    }

  return (! ic_info->key_unhandled && mtext_nchars (ic->produced) == 0);
}


/** Return 1 if the last event or key was not handled, otherwise
    return 0.

    There is no need of looking up because ic->produced should already
    contain the produced text (if any).

    Ignore KEY.  */

static int
lookup (MInputContext *ic, MSymbol key, void *arg, MText *mt)
{
  mtext_cat (mt, ic->produced);
  mtext_reset (ic->produced);
  return (((MInputContextInfo *) ic->info)->key_unhandled ? -1 : 0);
}

static MPlist *load_im_info_keys;

static MPlist *
load_partial_im_info (MSymbol language, MSymbol name,
                      MSymbol extra, MSymbol key)
{
  MDatabase *mdb;
  MPlist *plist;

  if (language == Mnil)
    MERROR (MERROR_IM, NULL);
  mdb = mdatabase_find (Minput_method, language, name, extra);
  if (! mdb)
    MERROR (MERROR_IM, NULL);

  mplist_push (load_im_info_keys, key, Mt);
  plist = mdatabase__load_for_keys (mdb, load_im_info_keys);
  mplist_pop (load_im_info_keys);
  return plist;
}


static MInputMethodInfo *
get_im_info (MSymbol language, MSymbol name, MSymbol extra)
{
  MDatabase *mdb;
  MPlist *plist;
  MInputMethodInfo *im_info = NULL;

  if (language == Mnil)
    MERROR (MERROR_IM, NULL);
  mdb = mdatabase_find (Minput_method, language, name, extra);
  if (! mdb)
    MERROR (MERROR_IM, NULL);

  if (! im_info_list)
    im_info_list = mplist ();
  else if ((plist = mplist_find_by_value (im_info_list, mdb)))
    {
      if (mdatabase__check (mdb))
        {
          plist = MPLIST_NEXT (plist);
          im_info = MPLIST_VAL (plist);
          return im_info;
        }
      mplist_pop (plist);
      free_im_info (MPLIST_VAL (plist));
      mplist_pop (plist);
    }

  plist = mdatabase_load (mdb);
  if (! plist)
    MERROR (MERROR_IM, NULL);
  im_info = load_im_info (language, name, plist);
  M17N_OBJECT_UNREF (plist);
  if (! im_info)
    MERROR (MERROR_IM, NULL);
  mplist_push (im_info_list, Mt, im_info);
  mplist_push (im_info_list, Mt, mdb);
  return im_info;
}

\f
/* Input method command handler.  */

/* List of all (global and local) commands. 
   (LANG:(IM-NAME:(COMMAND ...) ...) ...) ...
   COMMAND is CMD-NAME:(mtext:DESCRIPTION plist:KEYSEQ ...))
   Global commands are storead as (t (t COMMAND ...))  */

/* Check if PLIST is a valid command key sequence.
   PLIST must be NULL or:
   [ symbol:KEY | integer:KEY ] ...  */

static int
check_command_keyseq (MPlist *plist)
{
  if (! plist)
    return 0;
  MPLIST_DO (plist, plist)
    {
      if (MPLIST_SYMBOL_P (plist))
        continue;
      else if (MPLIST_INTEGER_P (plist))
        {
          int n = MPLIST_INTEGER (plist);

          if (n < 0 || n > 9)
            return -1;
          MPLIST_KEY (plist) = Msymbol;
          MPLIST_VAL (plist) = one_char_symbol['0' + 9];
        }
      else
        return -1;
    }
  return 0;
}

/* Check if PLIST has this form:
     ([ plist:([ symbol:KEY | integer:KEY ]) | mtext:KEYSEQ ]
      ...)
   If the form of PLIST matches, return 0, otherwise return -1.  */

static int
check_command_list (MPlist *plist)
{
  MPLIST_DO (plist, plist)
    {
      if (MPLIST_PLIST_P (plist))
        {
          MPlist *pl = MPLIST_PLIST (plist);

          MPLIST_DO (pl, pl)
            if (! MPLIST_SYMBOL_P (pl) && ! MPLIST_INTEGER_P (pl))
              return -1;
        }
      else if (! MPLIST_MTEXT_P (plist))
        return -1;
    }
  return 0;
}


\f
/* Input method variable handler.  */

/* Check if PLIST has this form:
     (TYPE:VAL   ;; TYPE ::= integer | mtext | symbol
      VALID-VALUE
      ...)
   If the form of PLIST matches, return 0, otherwise return -1.  */

static int
check_variable_list (MPlist *plist)
{
  MSymbol type = MPLIST_KEY (plist);
  MPlist *p; 

  if (type != Minteger && type != Mtext && type != Msymbol)
    return -1;
  MPLIST_DO (plist, MPLIST_NEXT (plist))
    {
      if (type == Minteger && MPLIST_PLIST_P (plist))
        {
          MPLIST_DO (p, MPLIST_PLIST (plist))
            if (! MPLIST_INTEGER_P (p))
              return -1;
        }
      else if (type != MPLIST_KEY (plist))
        return -1;
    }
  return 0;
}

/* Support functions for mdebug_dump_im.  */

static void
dump_im_map (MPlist *map_list, int indent)
{
  char *prefix;
  MSymbol key = MPLIST_KEY (map_list);
  MIMMap *map = (MIMMap *) MPLIST_VAL (map_list);

  prefix = (char *) alloca (indent + 1);
  memset (prefix, 32, indent);
  prefix[indent] = '\0';

  fprintf (stderr, "(\"%s\" ", msymbol_name (key));
  if (map->map_actions)
    mdebug_dump_plist (map->map_actions, indent + 2);
  if (map->submaps)
    {
      MPLIST_DO (map_list, map->submaps)
        {
          fprintf (stderr, "\n%s  ", prefix);
          dump_im_map (map_list, indent + 2);
        }
    }
  if (map->branch_actions)
    {
      fprintf (stderr, "\n%s  (branch\n%s    ", prefix, prefix);
      mdebug_dump_plist (map->branch_actions, indent + 4);
      fprintf (stderr, ")");      
    }
  fprintf (stderr, ")");
}


static void
dump_im_state (MIMState *state, int indent)
{
  char *prefix;
  MPlist *map_list;

  prefix = (char *) alloca (indent + 1);
  memset (prefix, 32, indent);
  prefix[indent] = '\0';

  fprintf (stderr, "(%s", msymbol_name (state->name));
  if (state->map->submaps)
    {
      MPLIST_DO (map_list, state->map->submaps)
        {
          fprintf (stderr, "\n%s  ", prefix);
          dump_im_map (map_list, indent + 2);
        }
    }
  fprintf (stderr, ")");
}

\f

int
minput__init ()
{
  char *key_names[32]
    = { NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
        "BackSpace", "Tab", "Linefeed", "Clear", NULL, "Return", NULL, NULL,
        NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
        NULL, NULL, NULL, "Escape", NULL, NULL, NULL, NULL };
  char buf[6], buf2[256];
  int i;
  MPlist *plist;

  Minput_method = msymbol ("input-method");
  Minput_driver = msymbol ("input-driver");
  Mtitle = msymbol ("title");
  Mmacro = msymbol ("macro");
  Mmodule = msymbol ("module");
  Mmap = msymbol ("map");
  Mstate = msymbol ("state");
  Minclude = msymbol ("include");
  Minsert = msymbol ("insert");
  M_candidates = msymbol ("  candidates");
  Mdelete = msymbol ("delete");
  Mmove = msymbol ("move");
  Mmark = msymbol ("mark");
  Mpushback = msymbol ("pushback");
  Mundo = msymbol ("undo");
  Mcall = msymbol ("call");
  Mshift = msymbol ("shift");
  Mselect = msymbol ("select");
  Mshow = msymbol ("show");
  Mhide = msymbol ("hide");
  Mcommit = msymbol ("commit");
  Munhandle = msymbol ("unhandle");
  Mset = msymbol ("set");
  Madd = msymbol ("add");
  Msub = msymbol ("sub");
  Mmul = msymbol ("mul");
  Mdiv = msymbol ("div");
  Mequal = msymbol ("=");
  Mless = msymbol ("<");
  Mgreater = msymbol (">");

  Mcandidates_group_size = msymbol ("candidates-group-size");
  Mcandidates_charset = msymbol ("candidates-charset");

  Minput_preedit_start = msymbol ("input-preedit-start");
  Minput_preedit_done = msymbol ("input-preedit-done");
  Minput_preedit_draw = msymbol ("input-preedit-draw");
  Minput_status_start = msymbol ("input-status-start");
  Minput_status_done = msymbol ("input-status-done");
  Minput_status_draw = msymbol ("input-status-draw");
  Minput_candidates_start = msymbol ("input-candidates-start");
  Minput_candidates_done = msymbol ("input-candidates-done");
  Minput_candidates_draw = msymbol ("input-candidates-draw");
  Minput_set_spot = msymbol ("input-set-spot");
  Minput_focus_move = msymbol ("input-focus-move");
  Minput_focus_in = msymbol ("input-focus-in");
  Minput_focus_out = msymbol ("input-focus-out");
  Minput_toggle = msymbol ("input-toggle");
  Minput_reset = msymbol ("input-reset");
  Minput_get_surrounding_text = msymbol ("input-get-surrounding-text");
  Minput_delete_surrounding_text = msymbol ("input-delete-surrounding-text");

  Mcandidate_list = msymbol_as_managing_key ("  candidate-list");
  Mcandidate_index = msymbol ("  candidate-index");

  Minit = msymbol ("init");
  Mfini = msymbol ("fini");

  M_key_alias = msymbol ("  key-alias");
  M_description = msymbol ("description");
  M_command = msymbol ("command");
  M_variable = msymbol ("variable");

  load_im_info_keys = mplist ();
  plist = mplist_add (load_im_info_keys, Mstate, Mnil);

  buf[0] = 'C';
  buf[1] = '-';
  buf[3] = '\0';
  for (i = 0, buf[2] = '@'; i < ' '; i++, buf[2]++)
    {
      MSymbol alias;

      one_char_symbol[i] = msymbol (buf);
      if (key_names[i])
        {
          alias = msymbol (key_names[i]);
          msymbol_put (one_char_symbol[i], M_key_alias,  alias);
        }
      else
        alias = one_char_symbol[i];
      buf[2] += (i == 0) ? -32 : 32;
      msymbol_put (alias, M_key_alias,  msymbol (buf));
      buf[2] -= (i == 0) ? -32 : 32;
    }
  for (buf[2] = i; i < 127; i++, buf[2]++)
    one_char_symbol[i] = msymbol (buf + 2);
  one_char_symbol[i++] = msymbol ("Delete");
  buf[2] = 'M';
  buf[3] = '-';
  buf[5] = '\0';
  buf2[0] = 'M';
  buf2[1] = '-';
  for (buf[4] = '@'; i < 160; i++, buf[4]++)
    {
      one_char_symbol[i] = msymbol (buf);
      if (key_names[i - 128])
        {
          strcpy (buf2 + 2, key_names[i - 128]);
          msymbol_put (one_char_symbol[i], M_key_alias,  msymbol (buf2));
        }
    }
  for (buf[4] = i - 128; i < 255; i++, buf[4]++)
    one_char_symbol[i] = msymbol (buf + 2);
  one_char_symbol[i] = msymbol ("M-Delete");

  command_list = variable_list = NULL;

  minput_default_driver.open_im = open_im;
  minput_default_driver.close_im = close_im;
  minput_default_driver.create_ic = create_ic;
  minput_default_driver.destroy_ic = destroy_ic;
  minput_default_driver.filter = filter;
  minput_default_driver.lookup = lookup;
  minput_default_driver.callback_list = mplist ();
  mplist_put (minput_default_driver.callback_list, Minput_reset,
              (void *) reset_ic);
  minput_driver = &minput_default_driver;
  return 0;
}

void
minput__fini ()
{
  if (command_list)
    {
      M17N_OBJECT_UNREF (command_list);
      command_list = NULL;
    }
  if (variable_list)
    {
      M17N_OBJECT_UNREF (variable_list);
      variable_list = NULL;
    }

  if (minput_default_driver.callback_list)
    {
      M17N_OBJECT_UNREF (minput_default_driver.callback_list);
      minput_default_driver.callback_list = NULL;
    }
  if (minput_driver->callback_list)
    {
      M17N_OBJECT_UNREF (minput_driver->callback_list);
      minput_driver->callback_list = NULL;
    }

  if (im_info_list)
    {
      while (! MPLIST_TAIL_P (im_info_list))
        {
          /* Pop (t . mdb) */
          mplist_pop (im_info_list);
          free_im_info ((MInputMethodInfo *) MPLIST_VAL (im_info_list));
          /* Pop (t . im_info) */
          mplist_pop (im_info_list);
        }
      M17N_OBJECT_UNREF (im_info_list);
      im_info_list = NULL;
    }
 
  M17N_OBJECT_UNREF (load_im_info_keys);
}

void
minput__callback (MInputContext *ic, MSymbol command)
{
  if (ic->im->driver.callback_list)
    {
      MInputCallbackFunc func
        = (MInputCallbackFunc) mplist_get (ic->im->driver.callback_list,
                                           command);

      if (func)
        (func) (ic, command);
    }
}

MSymbol
minput__char_to_key (int c)
{
  if (c < 0 || c >= 0x100)
    return Mnil;

  return one_char_symbol[c];
}

/*** @} */
#endif /* !FOR_DOXYGEN || DOXYGEN_INTERNAL_MODULE */

\f
/* External API */

/*** @addtogroup m17nInputMethod */
/*** @{ */
/*=*/

/***en
    @name Variables: Predefined symbols for callback commands.

    These are the predefined symbols that are used as the @c COMMAND
    argument of callback functions of an input method driver (see
    #MInputDriver::callback_list ).  

    Most of them don't require extra argument nor return any value;
    exceptions are these:

    Minput_get_surrounding_text: When a callback function assigned for
    this command is called, the first element of #MInputContext::plist
    has key #Msymbol and the value specifies which portion of the
    surrounding text should be retrieved.  If the value is positive,
    it specifies the number of characters following the current cursor
    position.  If the value is negative, the absolute value specifies
    the number of characters preceding the current cursor position.
    The callback function must set the key of this element to #Mtext
    and the value to the retrived M-text (whose length may be shorter
    than the requested number of characters if the available text is
    not that long, or it may be longer if an application thinks it's
    more efficient to return that length).

    Minput_delete_surrounding_text: When a callback function assigned
    for this command is called, the first element of
    #MInputContext::plist has key #Msymbol and the value specifies
    which portion of the surrounding text should be deleted in the
    same way as the case of Minput_get_surrounding_text.  The callback
    function must delete the specified text.  It should not alter
    #MInputContext::plist.  */ 

/***ja
    @name ÊÑ¿ô¡§ ¥³¡¼¥ë¥Ð¥Ã¥¯¥³¥Þ¥ó¥ÉÍÑÄêµÁºÑ¤ß¥·¥ó¥Ü¥ë.

    ÆþÎϥ᥽¥Ã¥É¥É¥é¥¤¥Ð¤Î¥³¡¼¥ë¥Ð¥Ã¥¯´Ø¿ô¤Ë¤ª¤¤¤Æ @c COMMAND 
    °ú¿ô¤È¤·¤ÆÍѤ¤¤é¤ì¤ëÄêµÁºÑ¤ß¥·¥ó¥Ü¥ë (#MInputDriver::callback_list »²¾È)¡£
      */ 
/*** @{ */ 
/*=*/

MSymbol Minput_preedit_start;
MSymbol Minput_preedit_done;
MSymbol Minput_preedit_draw;
MSymbol Minput_status_start;
MSymbol Minput_status_done;
MSymbol Minput_status_draw;
MSymbol Minput_candidates_start;
MSymbol Minput_candidates_done;
MSymbol Minput_candidates_draw;
MSymbol Minput_set_spot;
MSymbol Minput_toggle;
MSymbol Minput_reset;
MSymbol Minput_get_surrounding_text;
MSymbol Minput_delete_surrounding_text;
/*** @} */

/*=*/

/***en
    @name Variables: Predefined symbols for special input events.

    These are the predefined symbols that are used as the @c KEY
    argument of minput_filter ().  */ 

/*** @{ */ 
/*=*/

MSymbol Minput_focus_out;
MSymbol Minput_focus_in;
MSymbol Minput_focus_move;

/*** @} */

/*=*/

/***en
    @brief The default driver for internal input methods.

    The variable #minput_default_driver is the default driver for
    internal input methods.

    The member MInputDriver::open_im () searches the m17n database for
    an input method that matches the tag \< #Minput_method, $LANGUAGE,
    $NAME\> and loads it.

    The member MInputDriver::callback_list () is @c NULL.  Thus, it is
    programmers responsibility to set it to a plist of proper callback
    functions.  Otherwise, no feedback information (e.g. preedit text)
    can be shown to users.

    The macro M17N_INIT () sets the variable #minput_driver to the
    pointer to this driver so that all internal input methods use it.

    Therefore, unless @c minput_driver is set differently, the driver
    dependent arguments $ARG of the functions whose name begin with
    "minput_" are all ignored.  */

/***ja
    @brief ÆâÉôÆþÎϥ᥽¥Ã¥ÉÍѥǥե©¥ë¥È¥É¥é¥¤¥Ð.

    ÊÑ¿ô #minput_default_driver ¤ÏÆâÉôÆþÎϥ᥽¥Ã¥ÉÍѤΥǥե©¥ë¥È¤Î¥É¥é¥¤¥Ð¤òɽ¤¹¡£

    ¥á¥ó¥Ð MInputDriver::open_im () ¤Ï m17n ¥Ç¡¼¥¿¥Ù¡¼¥¹Ã椫¤é¥¿¥° 
    \< #Minput_method, $LANGUAGE, $NAME\> 
    ¤Ë¹çÃפ¹¤ëÆþÎϥ᥽¥Ã¥É¤òõ¤·¡¢¤½¤ì¤ò¥í¡¼¥É¤¹¤ë¡£

    ¥á¥ó¥Ð MInputDriver::callback_list () ¤Ï @c NULL ¤Ç¤¢¤ê¡¢
    ¤·¤¿¤¬¤Ã¤Æ¡¢¥×¥í¥°¥é¥Þ¦¤ÇÀÕǤ¤ò»ý¤Ã¤Æ ŬÀڤʥ³¡¼¥ë¥Ð¥Ã¥¯´Ø¿ô¤Î plist
    ¤ËÀßÄꤷ¤Ê¤¯¤Æ¤Ï¤Ê¤é¤Ê¤¤¡£¤µ¤â¤Ê¤¤¤È¡¢preedit 
    ¥Æ¥­¥¹¥È¤Ê¤É¤Î¥Õ¥£¡¼¥É¥Ð¥Ã¥¯¾ðÊ󤬥桼¥¶¤Ëɽ¼¨¤µ¤ì¤Ê¤¤¡£

    ¥Þ¥¯¥í M17N_INIT () ¤ÏÊÑ¿ô #minput_driver 
    ¤ò¤³¤Î¥É¥é¥¤¥Ð¤Ø¤Î¥Ý¥¤¥ó¥¿¤ËÀßÄꤷ¡¢Á´¤Æ¤ÎÆâÉôÆþÎϥ᥽¥Ã¥É¤¬¤³¤Î¥É¥é¥¤¥Ð¤ò»È¤¦¤è¤¦¤Ë¤¹¤ë¡£

    ¤·¤¿¤¬¤Ã¤Æ¡¢@c minput_driver ¤¬¥Ç¥Õ¥©¥ë¥ÈÃͤΤޤޤǤ¢¤ì¤Ð¡¢minput_ 
    ¤Ç»Ï¤Þ¤ë´Ø¿ô¤Î¥É¥é¥¤¥Ð¤Ë°Í¸¤¹¤ë°ú¿ô $ARG ¤Ï¤¹¤Ù¤Æ̵»ë¤µ¤ì¤ë¡£  */

MInputDriver minput_default_driver;
/*=*/

/***en
    @brief The driver for internal input methods.

    The variable #minput_driver is a pointer to the input method
    driver that is used by internal input methods.  The macro
    M17N_INIT () initializes it to a pointer to #minput_default_driver
    if <m17n<EM></EM>.h> is included.  */ 
/***ja
    @brief ÆâÉôÆþÎϥ᥽¥Ã¥ÉÍѥɥ饤¥Ð.

    ÊÑ¿ô #minput_driver ¤ÏÆâÉôÆþÎϥ᥽¥Ã¥É¤Ë¤è¤Ã¤Æ»ÈÍѤµ¤ì¤Æ¤¤¤ëÆþÎÏ¥á
    ¥½¥Ã¥É¥É¥é¥¤¥Ð¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë¡£¥Þ¥¯¥í M17N_INIT () ¤Ï¤³¤Î¥Ý¥¤¥ó
    ¥¿¤ò#minput_default_driver (<m17n<EM></EM>.h> ¤¬ include ¤µ¤ì¤Æ¤¤¤ë
    »þ) ¤Ë½é´ü²½¤¹¤ë¡£  */ 

MInputDriver *minput_driver;

MSymbol Minput_driver;

/*=*/

/***en
    @brief Open an input method.

    The minput_open_im () function opens an input method that matches
    language $LANGUAGE and name $NAME, and returns a pointer to the
    input method object newly allocated.

    This function at first decides an driver for the input method as
    below.

    If $LANGUAGE is not #Mnil, the driver pointed by the variable
    #minput_driver is used.

    If $LANGUAGE is #Mnil and $NAME has #Minput_driver property, the
    driver pointed to by the property value is used to open the input
    method.  If $NAME has no such property, @c NULL is returned.

    Then, the member MInputDriver::open_im () of the driver is
    called.  

    $ARG is set in the member @c arg of the structure MInputMethod so
    that the driver can refer to it.  */

/***ja
    @brief ÆþÎϥ᥽¥Ã¥É¤ò¥ª¡¼¥×¥ó¤¹¤ë.

    ´Ø¿ô minput_open_im () ¤Ï¸À¸ì $LANGUAGE ¤È̾Á° $NAME 
    ¤Ë¹çÃפ¹¤ëÆþÎϥ᥽¥Ã¥É¤ò¥ª¡¼¥×¥ó¤·¡¢¿·¤¿¤Ë³ä¤êÅö¤Æ¤é¤ì¤¿ÆþÎϥ᥽¥Ã¥É¥ª¥Ö¥¸¥§¥¯¥È¤Ø¤Î¥Ý¥¤¥ó¥¿¤òÊÖ¤¹¡£
    
    ¤³¤Î´Ø¿ô¤Ï¡¢¤Þ¤ºÆþÎϥ᥽¥Ã¥ÉÍѤΥɥ饤¥Ð¤ò°Ê²¼¤Î¤è¤¦¤Ë¤·¤Æ·èÄꤹ¤ë¡£

    $LANGUAGE ¤¬ #Mnil ¤Ç¤Ê¤±¤ì¤Ð¡¢ÊÑ¿ô #minput_driver 
    ¤Ç»Ø¤µ¤ì¤Æ¤¤¤ë¥É¥é¥¤¥Ð¤òÍѤ¤¤ë¡£

    $LANGUAGE ¤¬ #Mnil ¤Ç¤¢¤ê¡¢$NAME ¤¬ #Minput_driver
    ¥×¥í¥Ñ¥Æ¥£¤ò»ý¤Ä¾ì¹ç¤Ë¤Ï¡¢¤½¤Î¥×¥í¥Ñ¥Æ¥£¤ÎÃͤǻؤµ¤ì¤Æ¤¤¤ëÆþÎϥɥ饤¥Ð¤òÍѤ¤¤ÆÆþÎϥ᥽¥Ã¥É¤ò¥ª¡¼¥×¥ó¤¹¤ë¡£
    $NAME ¤Ë¤½¤Î¤è¤¦¤Ê¥×¥í¥Ñ¥Æ¥£¤¬Ìµ¤«¤Ã¤¿¾ì¹ç¤Ï @c NULL ¤òÊÖ¤¹¡£

    ¼¡¤¤¤Ç¡¢¥É¥é¥¤¥Ð¤Î¥á¥ó¥Ð MInputDriver::open_im () ¤¬¸Æ¤Ð¤ì¤ë¡£

    $ARG ¤Ï¹½Â¤ÂÎ MInputMethod ¤Î¥á¥ó¥Ð @c arg ¤ËÀßÄꤵ¤ì¡¢¥É¥é¥¤¥Ð¤«¤é»²¾È¤Ç¤­¤ë¡£

    @latexonly \IPAlabel{minput_open} @endlatexonly

*/

MInputMethod *
minput_open_im (MSymbol language, MSymbol name, void *arg)
{
  MInputMethod *im;
  MInputDriver *driver;

  MDEBUG_PRINT2 ("  [IM] opening (%s %s) ... ",
         msymbol_name (language), msymbol_name (name));
  if (language)
    driver = minput_driver;
  else
    {
      driver = (MInputDriver *) msymbol_get (name, Minput_driver);
      if (! driver)
        MERROR (MERROR_IM, NULL);
    }

  MSTRUCT_CALLOC (im, MERROR_IM);
  im->language = language;
  im->name = name;
  im->arg = arg;
  im->driver = *driver;
  if ((*im->driver.open_im) (im) < 0)
    {
      MDEBUG_PRINT (" failed\n");
      free (im);
      return NULL;
    }
  MDEBUG_PRINT (" ok\n");
  return im;
}

/*=*/

/***en
    @brief Close an input method.

    The minput_close_im () function closes the input method $IM, which
    must have been created by minput_open_im ().  */

/***ja
    @brief ÆþÎϥ᥽¥Ã¥É¤ò¥¯¥í¡¼¥º¤¹¤ë.

    ´Ø¿ô minput_close_im () ¤Ï¡¢ÆþÎϥ᥽¥Ã¥É $IM ¤ò¥¯¥í¡¼¥º¤¹¤ë¡£
    ¤³¤ÎÆþÎϥ᥽¥Ã¥É $IM ¤Ï minput_open_im () ¤Ë¤è¤Ã¤Æºî¤é¤ì¤¿¤â¤Î¤Ç¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£  */

void
minput_close_im (MInputMethod *im)
{
  MDEBUG_PRINT2 ("  [IM] closing (%s %s) ... ",
                 msymbol_name (im->name), msymbol_name (im->language));
  (*im->driver.close_im) (im);
  free (im);
  MDEBUG_PRINT (" done\n");
}

/*=*/

/***en
    @brief Create an input context.

    The minput_create_ic () function creates an input context object
    associated with input method $IM, and calls callback functions
    corresponding to #Minput_preedit_start, #Minput_status_start, and
    #Minput_status_draw in this order.

    @return

    If an input context is successfully created, minput_create_ic ()
    returns a pointer to it.  Otherwise it returns @c NULL.  */

/***ja
    @brief ÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È¤òÀ¸À®¤¹¤ë.

    ´Ø¿ô minput_create_ic () ¤ÏÆþÎϥ᥽¥Ã¥É $IM
    ¤ËÂбþ¤¹¤ëÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È¥ª¥Ö¥¸¥§¥¯¥È¤òÀ¸À®¤·¡¢
    #Minput_preedit_start, #Minput_status_start, #Minput_status_draw
    ¤ËÂбþ¤¹¤ë¥³¡¼¥ë¥Ð¥Ã¥¯´Ø¿ô¤ò¤³¤Î½ç¤Ë¸Æ¤Ö¡£

    @return

    ÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È¤¬À¸À®¤µ¤ì¤¿¾ì¹ç¡¢minput_create_ic () 
    ¤Ï¤½¤ÎÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È¤Ø¤Î¥Ý¥¤¥ó¥¿¤òÊÖ¤¹¡£¼ºÇÔ¤·¤¿¾ì¹ç¤Ï @c NULL ¤òÊÖ¤¹¡£
      */

MInputContext *
minput_create_ic (MInputMethod *im, void *arg)
{
  MInputContext *ic;

  MDEBUG_PRINT2 ("  [IM] creating context (%s %s) ... ",
                 msymbol_name (im->name), msymbol_name (im->language));
  MSTRUCT_CALLOC (ic, MERROR_IM);
  ic->im = im;
  ic->arg = arg;
  ic->preedit = mtext ();
  ic->candidate_list = NULL;
  ic->produced = mtext ();
  ic->spot.x = ic->spot.y = 0;
  ic->active = 1;
  ic->plist = mplist ();
  if ((*im->driver.create_ic) (ic) < 0)
    {
      MDEBUG_PRINT (" failed\n");
      M17N_OBJECT_UNREF (ic->preedit);
      M17N_OBJECT_UNREF (ic->produced);
      M17N_OBJECT_UNREF (ic->plist);
      free (ic);
      return NULL;
    };

  if (im->driver.callback_list)
    {
      minput__callback (ic, Minput_preedit_start);
      minput__callback (ic, Minput_status_start);
      minput__callback (ic, Minput_status_draw);
    }

  MDEBUG_PRINT (" ok\n");
  return ic;
}

/*=*/

/***en
    @brief Destroy an input context.

    The minput_destroy_ic () function destroys the input context $IC,
    which must have been created by minput_create_ic ().  It calls
    callback functions corresponding to #Minput_preedit_done,
    #Minput_status_done, and #Minput_candidates_done in this order.  */

/***ja
    @brief ÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È¤òÇ˲õ¤¹¤ë.

    ´Ø¿ô minput_destroy_ic () ¤Ï¡¢ÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È $IC ¤òÇ˲õ¤¹¤ë¡£
    ¤³¤ÎÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È¤Ï minput_create_ic () 
    ¤Ë¤è¤Ã¤Æºî¤é¤ì¤¿¤â¤Î¤Ç¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£¤³¤Î´Ø¿ô¤Ï 
    #Minput_preedit_done, #Minput_status_done, #Minput_candidates_done 
    ¤ËÂбþ¤¹¤ë¥³¡¼¥ë¥Ð¥Ã¥¯´Ø¿ô¤ò¤³¤Î½ç¤Ë¸Æ¤Ö¡£
  */

void
minput_destroy_ic (MInputContext *ic)
{
  MDEBUG_PRINT2 ("  [IM] destroying context (%s %s) ... ",
                 msymbol_name (ic->im->name), msymbol_name (ic->im->language));
  if (ic->im->driver.callback_list)
    {
      minput__callback (ic, Minput_preedit_done);
      minput__callback (ic, Minput_status_done);
      minput__callback (ic, Minput_candidates_done);
    }
  (*ic->im->driver.destroy_ic) (ic);
  M17N_OBJECT_UNREF (ic->preedit);
  M17N_OBJECT_UNREF (ic->produced);
  M17N_OBJECT_UNREF (ic->plist);
  MDEBUG_PRINT (" done\n");
  free (ic);
}

/*=*/

/***en
    @brief Filter an input key.

    The minput_filter () function filters input key $KEY according to
    input context $IC, and calls callback functions corresponding to
    #Minput_preedit_draw, #Minput_status_draw, and
    #Minput_candidates_draw if the preedit text, the status, and the
    current candidate are changed respectively.

    To make the input method commit the current preedit text (if any)
    and shift to the initial state, call this function with #Mnil as
    $KEY.

    To inform the input method about the focus-out event, call this
    function with #Minput_focus_out as $KEY.

    To inform the input method about the focus-in event, call this
    function with #Minput_focus_in as $KEY.

    To inform the input method about the focus-move event (i.e. input
    spot change within the same input context), call this function
    with #Minput_focus_move as $KEY.

    @return
    If $KEY is filtered out, this function returns 1.  In that case,
    the caller should discard the key.  Otherwise, it returns 0, and
    the caller should handle the key, for instance, by calling the
    function minput_lookup () with the same key.  */

/***ja
    @brief ÆþÎÏ¥­¡¼¤ò¥Õ¥£¥ë¥¿¤¹¤ë.

    ´Ø¿ô minput_filter () ¤ÏÆþÎÏ¥­¡¼ $KEY ¤òÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È $IC 
    ¤Ë±þ¤¸¤Æ¥Õ¥£¥ë¥¿¤·¡¢preedit ¥Æ¥­¥¹¥È¡¢¥¹¥Æ¡¼¥¿¥¹¡¢¸½»þÅÀ¤Ç¤Î¸õÊ䤬ÊѲ½¤·¤¿»þÅÀ¤Ç¡¢¤½¤ì¤¾¤ì
    #Minput_preedit_draw, #Minput_status_draw,
    #Minput_candidates_draw ¤ËÂбþ¤¹¤ë¥³¡¼¥ë¥Ð¥Ã¥¯´Ø¿ô¤ò¸Æ¤Ö¡£

    @return 
    $KEY ¤¬¥Õ¥£¥ë¥¿¤µ¤ì¤ì¤Ð¡¢¤³¤Î´Ø¿ô¤Ï 1 ¤òÊÖ¤¹¡£
    ¤³¤Î¾ì¹ç¸Æ¤Ó½Ð¤·Â¦¤Ï¤³¤Î¥­¡¼¤ò¼Î¤Æ¤ë¤Ù¤­¤Ç¤¢¤ë¡£
    ¤½¤¦¤Ç¤Ê¤±¤ì¤Ð 0 ¤òÊÖ¤·¡¢¸Æ¤Ó½Ð¤·Â¦¤Ï¡¢¤¿¤È¤¨¤ÐƱ¤¸¥­¡¼¤Ç´Ø¿ô minput_lookup ()
    ¤ò¸Æ¤Ö¤Ê¤É¤·¤Æ¡¢¤³¤Î¥­¡¼¤ò½èÍý¤¹¤ë¡£

    @latexonly \IPAlabel{minput_filter} @endlatexonly
*/

int
minput_filter (MInputContext *ic, MSymbol key, void *arg)
{
  int ret;

  if (! ic
      || ! ic->active)
    return 0;
  ret = (*ic->im->driver.filter) (ic, key, arg);

  if (ic->im->driver.callback_list)
    {
      if (ic->preedit_changed)
        minput__callback (ic, Minput_preedit_draw);
      if (ic->status_changed)
        minput__callback (ic, Minput_status_draw);
      if (ic->candidates_changed)
        minput__callback (ic, Minput_candidates_draw);
    }

  return ret;
}

/*=*/

/***en
    @brief Look up a text produced in the input context.

    The minput_lookup () function looks up a text in the input context
    $IC.  $KEY must be the same one provided to the previous call of
    minput_filter ().

    If a text was produced by the input method, it is concatenated
    to M-text $MT.

    This function calls #MInputDriver::lookup .

    @return
    If $KEY was correctly handled by the input method, this function
    returns 0.  Otherwise, returns -1, even in that case, some text
    may be produced in $MT.  */

/***ja
    @brief ÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥ÈÃæ¤Î¥Æ¥­¥¹¥È¤òõ¤¹.

    ´Ø¿ô minput_lookup () ¤ÏÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È $IC Ãæ¤Î¥Æ¥­¥¹¥È¤òõ¤¹¡£
    $KEY ¤Ï´Ø¿ô minput_filter () ¤Ø¤ÎľÁ°¤Î¸Æ¤Ó½Ð¤·¤ËÍѤ¤¤é¤ì¤¿¤â¤Î¤ÈƱ¤¸¤Ç¤Ê¤¯¤Æ¤Ï¤Ê¤é¤Ê¤¤¡£

    ¥Æ¥­¥¹¥È¤¬ÆþÎϥ᥽¥Ã¥É¤Ë¤è¤Ã¤ÆÀ¸À®¤µ¤ì¤Æ¤¤¤ì¤Ð¡¢¥Æ¥­¥¹¥È¤Ï M-text
    $MT ¤ËÏ¢·ë¤µ¤ì¤ë¡£

    ¤³¤Î´Ø¿ô¤Ï¡¢#MInputDriver::lookup ¤ò¸Æ¤Ö¡£

    @return 
    $KEY ¤¬ÆþÎϥ᥽¥Ã¥É¤Ë¤è¤Ã¤ÆŬÀڤ˽èÍý¤Ç¤­¤ì¤Ð¡¢¤³¤Î´Ø¿ô¤Ï 0 ¤òÊÖ¤¹¡£
    ¤½¤¦¤Ç¤Ê¤±¤ì¤Ð -1 ¤òÊÖ¤¹¡£
    ¤³¤Î¾ì¹ç¤Ç¤â $MT ¤Ë²¿¤é¤«¤Î¥Æ¥­¥¹¥È¤¬À¸À®¤µ¤ì¤Æ¤¤¤ë¤³¤È¤¬¤¢¤ë¡£

    @latexonly \IPAlabel{minput_lookup} @endlatexonly  */

int
minput_lookup (MInputContext *ic, MSymbol key, void *arg, MText *mt)
{
  return (ic ? (*ic->im->driver.lookup) (ic, key, arg, mt) : -1);
}
/*=*/

/***en
    @brief Set the spot of the input context.

    The minput_set_spot () function set the spot of input context $IC
    to coordinate ($X, $Y ) with the height specified by $ASCENT and $DESCENT .
    The semantics of these values depend on the input method driver.

    For instance, a driver designed to work in a CUI environment may
    use $X and $Y as column and row numbers, and ignore $ASCENT and
    $DESCENT .  A driver designed to work in a window system may
    interpret $X and $Y as pixel offsets relative to the origin of the
    client window, and may interpret $ASCENT and $DESCENT as the ascent- and
    descent pixels of the line at ($X . $Y ).

    $FONTSIZE specifies the fontsize of preedit text in 1/10 point.

    $MT and $POS is the M-text and the character position at the spot.
    $MT may be @c NULL, in which case, the input method cannot get
    information about the text around the spot.  */

/***ja
    @brief ÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È¤Î¥¹¥Ý¥Ã¥È¤òÀßÄꤹ¤ë.

    ´Ø¿ô minput_set_spot () ¤Ï¡¢ÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È $IC ¤Î¥¹¥Ý¥Ã¥È¤ò¡¢ºÂɸ ($X, $Y )
    ¤Î°ÌÃÖ¤Ë ¡¢¹â¤µ $ASCENT¡¢ $DESCENT 
    ¤ÇÀßÄꤹ¤ë¡£ ¤³¤ì¤é¤ÎÃͤΰÕÌ£¤ÏÆþÎϥ᥽¥Ã¥É¥É¥é¥¤¥Ð¤Ë°Í¸¤¹¤ë¡£

    ¤¿¤È¤¨¤Ð CUI ´Ä¶­¤ÇÆ°ºî¤¹¤ë¥É¥é¥¤¥Ð¤Ï $X ¤È $Y 
    ¤ò¤½¤ì¤¾¤ìÎó¤È¹Ô¤ÎÈÖ¹æ¤È¤·¤ÆÍѤ¤¡¢$ASCENT ¤È $DESCENT 
    ¤ò̵»ë¤¹¤ë¤«¤â¤·¤ì¤Ê¤¤¡£ ¤Þ¤¿¥¦¥£¥ó¥É¥¦¥·¥¹¥Æ¥àÍѤΥɥ饤¥Ð¤Ï
    $X ¤È $Y ¤ò¥¯¥é¥¤¥¢¥ó¥È¥¦¥£¥ó¥É¥¦¤Î¸¶ÅÀ¤«¤é¤Î¥ª¥Õ¥»¥Ã¥È¤ò¥Ô¥¯¥»¥ëñ°Ì¤Çɽ¤·¤¿¤â¤Î¤È¤·¤Æ°·¤¤¡¢
    $ASCENT ¤È $DESCENT ¤ò ($X . $Y )
    ¤ÎÎó¤Î¥¢¥»¥ó¥È¤È¥Ç¥£¥»¥ó¥È¤ò¥Ô¥¯¥»¥ëñ°Ì¤Çɽ¤·¤¿¤â¤Î¤È¤·¤Æ°·¤¦¤«¤â¤·¤ì¤Ê¤¤¡£

    $FONTSIZE ¤Ë¤Ï preedit ¥Æ¥­¥¹¥È¤Î¥Õ¥©¥ó¥È¥µ¥¤¥º¤ò 1/10 ¥Ý¥¤¥ó¥Èñ°Ì¤Ç»ØÄꤹ¤ë¡£

    $MT ¤È $POS ¤Ï¤½¤Î¥¹¥Ý¥Ã¥È¤Î M-text ¤Èʸ»ú°ÌÃ֤Ǥ¢¤ë¡£$MT ¤Ï @c
    NULL ¤Ç¤â¤è¤¯¡¢¤½¤Î¾ì¹ç¤Ë¤ÏÆþÎϥ᥽¥Ã¥É¤Ï¥¹¥Ý¥Ã¥È¼þÊդΥƥ­¥¹¥È¤Ë´Ø¤¹¤ë¾ðÊó¤òÆÀ¤ë¤³¤È¤¬¤Ç¤­¤Ê¤¤¡£
    */

void
minput_set_spot (MInputContext *ic, int x, int y,
                 int ascent, int descent, int fontsize,
                 MText *mt, int pos)
{
  ic->spot.x = x;
  ic->spot.y = y;
  ic->spot.ascent = ascent;
  ic->spot.descent = descent;
  ic->spot.fontsize = fontsize;
  ic->spot.mt = mt;
  ic->spot.pos = pos;
  if (ic->im->driver.callback_list)
    minput__callback (ic, Minput_set_spot);
}
/*=*/

/***en
    @brief Toggle input method.

    The minput_toggle () function toggles the input method associated
    with input context $IC.  */
/***ja
    @brief ÆþÎϥ᥽¥Ã¥É¤òÀÚÂؤ¨¤ë.

    ´Ø¿ô minput_toggle () ¤ÏÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È $IC 
    ¤ËÂбþÉÕ¤±¤é¤ì¤¿ÆþÎϥ᥽¥Ã¥É¤ò¥È¥°¥ë¤¹¤ë¡£
    */

void
minput_toggle (MInputContext *ic)
{
  if (ic->im->driver.callback_list)
    minput__callback (ic, Minput_toggle);
  ic->active = ! ic->active;
}

/***en
    @brief Reset an input context.

    The minput_reset_ic () function resets input context $IC by
    calling a callback function corresponding to #Minput_reset.  It
    resets the status of $IC to the one of just after created.  As the
    current preedit text is deleted without commitment, if necessary,
    call minput_filter () with the arg @r key #Mnil to force the input
    method to commit the preedit in advance.  */

/***ja
    @brief ÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È¤ò¥ê¥»¥Ã¥È¤¹¤ë.

    ´Ø¿ô minput_reset_ic () ¤Ï #Minput_reset 
    ¤ËÂбþ¤¹¤ë¥³¡¼¥ë¥Ð¥Ã¥¯´Ø¿ô¤ò¸Æ¤Ö¤³¤È¤Ë¤è¤Ã¤ÆÆþÎÏ¥³¥ó¥Æ¥¯¥¹¥È $IC 
    ¤ò¥ê¥»¥Ã¥È¤¹¤ë¡£¥ê¥»¥Ã¥È¤È¤Ï¡¢¼ÂºÝ¤Ë¤ÏÆþÎϥ᥽¥Ã¥É¤ò½é´ü¾õÂ֤˰ܤ¹¤³¤È¤Ç¤¢¤ê¡¢¤·¤¿¤¬¤Ã¤Æ¡¢¤â¤·¸½ºßÆþÎÏÃæ¤Î¥Æ¥­¥¹¥È¤¬¤¢¤ì¤Ð¡¢¤½¤ì¤Ï¥³¥ß¥Ã¥È¤µ¤ì¤ë¡£
    ɬÍפʤé¤Ð¡¢¥¢¥×¥ê¥±¡¼¥·¥ç¥ó¥×¥í¥°¥é¥à¤Ï minput_lookup () 
    ¤òÆɤó¤Ç¤½¤Î¥³¥ß¥Ã¥È¤µ¤ì¤¿¥Æ¥­¥¹¥È¤ò¼è¤ê½Ð¤¹¤³¤È¤¬¤Ç¤­¡¢¤½¤ÎºÝ¡¢
    minput_lookup () ¤Î°ú¿ô @c KEY ¤È @c ARG 
    ¤Ï̵»ë¤µ¤ì¤ë¡£ */
void
minput_reset_ic (MInputContext *ic)
{
  if (ic->im->driver.callback_list)
    minput__callback (ic, Minput_reset);
}

/***en
    @brief Get description text of an input method.

    The minput_get_description () function returns an M-text that
    describes the input method specified by $LANGUAGE and $NAME.

    @return
    If the specified input method has a description text, a pointer to
    #MText is returned.  A caller have to free it by m17n_object_unref ().
    If the input method does not have a description text, @c NULL is
    returned.  */
/***ja
    @brief ÆþÎϥ᥽¥Ã¥É¤ÎÀâÌÀ¥Æ¥­¥¹¥È¤òÆÀ¤ë.

    ´Ø¿ô minput_get_description () ¤Ï¡¢$LANGUAGE ¤È $NAME ¤Ë¤è¤Ã¤Æ»ØÄê
    ¤µ¤ì¤¿ÆþÎϥ᥽¥Ã¥É¤òÀâÌÀ¤¹¤ë M-text ¤òÊÖ¤¹¡£

    @return »ØÄꤵ¤ì¤¿ÆþÎϥ᥽¥Ã¥É¤¬ÀâÌÀ¤¹¤ë¥Æ¥­¥¹¥È¤ò»ý¤Ã¤Æ¤¤¤ì¤Ð¡¢
    #MText ¤Ø¤Î¥Ý¥¤¥ó¥¿¤òÊÖ¤¹¡£¸Æ¤Ó½Ð¤·Â¦¤Ï¡¢¤½¤ì¤ò m17n_object_unref
    () ¤òÍѤ¤¤Æ²òÊü¤·¤Ê¤¯¤Æ¤Ï¤Ê¤é¤Ê¤¤¡£ÆþÎϥ᥽¥Ã¥É¤ËÀâÌÀ¥Æ¥­¥¹¥È¤¬Ìµ¤±
    ¤ì¤Ð@c NULL ¤òÊÖ¤¹¡£ */

MText *
minput_get_description (MSymbol language, MSymbol name)
{
  MPlist *plist = load_partial_im_info (language, name, Mnil, M_description);
  MPlist *pl;
  MText *mt;

  if (! plist)
    return NULL;
  pl = MPLIST_PLIST (plist);
  pl = MPLIST_NEXT (pl);
  if (MPLIST_MTEXT_P (pl))
    {
      mt = MPLIST_MTEXT (pl);
      M17N_OBJECT_REF (mt);
    }
  M17N_OBJECT_UNREF (plist);
  return mt;
}

/***en
    @brief Get information about input method commands.

    The minput_get_commands () function returns information about
    input method commands of the input method specified by $LANGUAGE
    and $NAME.  An input method command is a pseudo key event to which
    one or more actual input key sequences are assigned.

    There are two kinds of commands, global and local.  Global
    commands are used by multiple input methods for the same purpose,
    and have global key assignments.  Local commands are used only in
    a specific input method, and have only local key assignments.

    Each input method may locally change key assignments for global
    commands.  A global key assignment for a global command are
    effective only when the current input method does not have local
    key assignments for that command.

    If $NAME is #Mnil, information about global commands is returned.
    In this case $LANGUAGE is ignored.

    If $NAME is not #Mnil, information about those commands that have
    local key assignments in the input method specified by $LANGUAGE
    and $NAME is returned.

    @return
    If no input method commands are found, this function returns @c NULL.

    Otherwise, a pointer to a plist is returned.  The key of each
    element in the plist is a symbol representing a command, and the
    value is a plist of the form COMMAND-INFO described below.

    The first element of COMMAND-INFO has the key #Mtext, and the
    value is an M-text describing the command.

    If there are no more elements, that means no key sequences are
    assigned to the command.  Otherwise, each of the remaining
    elements has the key #Mplist, and the value is a plist whose keys are
    #Msymbol and values are symbols representing input keys, which are
    currently assigned to the command.

    As the returned plist is kept in the library, the caller must not
    modify nor free it.  */
/***ja
    @brief ÆþÎϥ᥽¥Ã¥É¤Î¥³¥Þ¥ó¥É¤Ë´Ø¤¹¤ë¾ðÊó¤òÆÀ¤ë.

    ´Ø¿ô minput_get_commands () ¤Ï¡¢ $LANGUAGE ¤È $NAME ¤Ë¤è¤Ã¤Æ»ØÄꤵ
    ¤ì¤¿ÆþÎϥ᥽¥Ã¥É¤ÎÆþÎϥ᥽¥Ã¥É¥³¥Þ¥ó¥É¤Ë´Ø¤¹¤ë¾ðÊó¤òÊÖ¤¹¡£ÆþÎϥ᥽¥Ã
    ¥É¥³¥Þ¥ó¥É¤È¤Ï¡¢µ¿»÷¥­¡¼¥¤¥Ù¥ó¥È¤Ç¤¢¤ê¡¢¤½¤ì¤¾¤ì¤Ë£±¤Ä°Ê¾å¤Î¼ÂºÝ¤Î
    ÆþÎÏ¥­¡¼¥·¡¼¥¯¥¨¥ó¥¹¤¬³ä¤êÅö¤Æ¤é¤ì¤Æ¤¤¤ë¤â¤Î¤ò»Ø¤¹¡£

    ¥³¥Þ¥ó¥É¤Ë¤Ï¥°¥í¡¼¥Ð¥ë¤È¥í¡¼¥«¥ë¤Î£²¼ïÎब¤¢¤ë¡£¥°¥í¡¼¥Ð¥ë¥³¥Þ¥ó¥É
    ¤ÏÊ£¿ô¤ÎÆþÎϥ᥽¥Ã¥É¤Ë¤ª¤¤¤Æ¡¢Æ±¤¸ÌÜŪ¤Ç¡¢¥°¥í¡¼¥Ð¥ë¤Ê¥­¡¼³ä¤êÅö¤Æ
    ¤ÇÍѤ¤¤é¤ì¤ë¡£¥í¡¼¥«¥ë¥³¥Þ¥ó¥É¤ÏÆÃÄê¤ÎÆþÎϥ᥽¥Ã¥É¤Ç¤Î¤ß¡¢¥í¡¼¥«¥ë
    ¤Ê¥­¡¼³äÅö¤Ç»ÈÍѤµ¤ì¤ë¡£

    ¸Ä¡¹¤ÎÆþÎϥ᥽¥Ã¥É¤Ï¥°¥í¡¼¥Ð¥ë¥³¥Þ¥ó¥É¤Î¥­¡¼³äÅö¤òÊѹ¹¤¹¤ë¤³¤È¤â¤Ç
    ¤­¤ë¡£¥°¥í¡¼¥Ð¥ë¥³¥Þ¥ó¥ÉÍѤΥ°¥í¡¼¥Ð¥ë¥­¡¼³ä¤êÅö¤Æ¤Ï¡¢»ÈÍѤ¹¤ëÆþÎÏ
    ¥á¥½¥Ã¥É¤Ë¤ª¤¤¤Æ¤½¤Î¥³¥Þ¥ó¥ÉÍÑ¤Î¥í¡¼¥«¥ë¤Ê¥­¡¼³äÅö¤¬Â¸ºß¤·¤Ê¤¤¾ì¹ç
    ¤Ë¤Î¤ßÍ­¸ú¤Ç¤¢¤ë¡£

    $NAME ¤¬ #Mnil ¤Ç¤¢¤ì¤Ð¡¢¥°¥í¡¼¥Ð¥ë¥³¥Þ¥ó¥É¤Ë´Ø¤¹¤ë¾ðÊó¤òÊÖ¤¹¡£¤³¤Î
    ¾ì¹ç¡¢$LANGUAGE ¤Ï̵»ë¤µ¤ì¤ë¡£

    $NAME ¤¬ #Mnil ¤Ç¤Ê¤±¤ì¤Ð¡¢$LANGUAGE ¤È $NAME ¤Ë¤è¤Ã¤Æ»ØÄꤵ¤ì¤ëÆþ
    Îϥ᥽¥Ã¥É¤ËÃÖ¤±¤ë¥í¡¼¥«¥ë¤Ê¥­¡¼³ä¤êÅö¤Æ¤ò»ý¤Ä¥³¥Þ¥ó¥É¤Ë´Ø¤¹¤ë¾ðÊó
    ¤òÊÖ¤¹¡£

    @return
    ÆþÎϥ᥽¥Ã¥É¥³¥Þ¥ó¥É¤¬¸«¤Ä¤«¤é¤Ê¤±¤ì¤Ð¡¢¤³¤Î´Ø¿ô¤Ï @c NULL ¤òÊÖ¤¹¡£

    ¤½¤¦¤Ç¤Ê¤±¤ì¤Ð¥×¥í¥Ñ¥Æ¥£¥ê¥¹¥È¤Ø¤Î¥Ý¥¤¥ó¥¿¤òÊÖ¤¹¡£¥ê¥¹¥È¤Î³ÆÍ×ÁǤÎ
    ¥­¡¼¤Ï¸Ä¡¹¤Î¥³¥Þ¥ó¥É¤ò¼¨¤¹¥·¥ó¥Ü¥ë¤Ç¤¢¤ê¡¢Ãͤϲ¼µ­¤Î COMMAND-INFO
    ¤Î·Á¼°¤Î¥×¥í¥Ñ¥Æ¥£¥ê¥¹¥È¤Ç¤¢¤ë¡£

    COMMAND-INFO ¤ÎÂè°ìÍ×ÁǤΥ­¡¼¤Ï #Mtext ¤Þ¤¿¤Ï #Msymbol ¤Ç¤¢¤ë¡£¥­¡¼
    ¤¬ #Mtext ¤Ê¤é¡¢ÃͤϤ½¤Î¥³¥Þ¥ó¥É¤òÀâÌÀ¤¹¤ë M-text ¤Ç¤¢¤ë¡£¥­¡¼¤¬
    #Msymbol ¤Ê¤éÃÍ¤Ï #Mnil ¤Ç¤¢¤ê¡¢¤³¤Î¥³¥Þ¥ó¥É¤ÏÀâÌÀ¥Æ¥­¥¹¥È¤ò»ý¤¿¤Ê
    ¤¤¤³¤È¤Ë¤Ê¤ë¡£

    ¤½¤ì°Ê³°¤ÎÍ×ÁǤ¬Ìµ¤±¤ì¤Ð¡¢¤³¤Î¥³¥Þ¥ó¥É¤ËÂФ·¤Æ¥­¡¼¥·¡¼¥¯¥¨¥ó¥¹¤¬³ä
    ¤êÅö¤Æ¤é¤ì¤Æ¤¤¤Ê¤¤¤³¤È¤ò°ÕÌ£¤¹¤ë¡£¤½¤¦¤Ç¤Ê¤±¤ì¤Ð¡¢»Ä¤ê¤Î³ÆÍ×ÁǤϥ­
    ¡¼¤È¤·¤Æ#Mplist ¤ò¡¢ÃͤȤ·¤Æ¥×¥í¥Ñ¥Æ¥£¥ê¥¹¥È¤ò»ý¤Ä¡£¤³¤Î¥×¥í¥Ñ¥Æ¥£
    ¥ê¥¹¥È¤Î¥­¡¼¤Ï #Msymbol ¤Ç¤¢¤ê¡¢Ãͤϸ½ºß¤½¤Î¥³¥Þ¥ó¥É¤Ë³ä¤êÅö¤Æ¤é¤ì
    ¤Æ¤¤¤ëÆþÎÏ¥­¡¼¤òɽ¤¹¥·¥ó¥Ü¥ë¤Ç¤¢¤ë¡£

    ÊÖ¤µ¤ì¤ë¥×¥í¥Ñ¥Æ¥£¥ê¥¹¥È¤Ï¥é¥¤¥Ö¥é¥ê¤Ë¤è¤Ã¤Æ´ÉÍý¤µ¤ì¤Æ¤ª¤ê¡¢¸Æ¤Ó½Ð
    ¤·Â¦¤ÇÊѹ¹¤·¤¿¤ê²òÊü¤·¤¿¤ê¤·¤Æ¤Ï¤Ê¤é¤Ê¤¤¡£*/

MPlist *
minput_get_commands (MSymbol language, MSymbol name)
{
  MPlist *plist = get_nested_list (language, name, Mnil, M_command);

  return (MPLIST_TAIL_P (plist) ? NULL : plist);
}

/***en
    @brief Assign a key sequence to an input method command.

    The minput_assign_command_keys () function assigns input key
    sequence $KEYSEQ to input method command $COMMAND for the input
    method specified by $LANGUAGE and $NAME.  If $NAME is #Mnil, the
    key sequence is assigned globally no matter what $LANGUAGE is.
    Otherwise the key sequence is assigned locally.

    Each element of $KEYSEQ must have the key $Msymbol and the value
    must be a symbol representing an input key.

    $KEYSEQ may be @c NULL, in which case, all assignments are deleted
    globally or locally.

    This assignment gets effective in a newly opened input method.

    @return
    If the operation was successful, 0 is returned.  Otherwise -1 is
    returned, and #merror_code is set to #MERROR_IM.  */
/***ja
    @brief ÆþÎϥ᥽¥Ã¥É¥³¥Þ¥ó¥É¤Ë¥­¡¼¥·¡¼¥¯¥¨¥ó¥¹¤ò³ä¤êÅö¤Æ¤ë.

    ´Ø¿ô minput_assign_command_keys () ¤Ï¡¢ $LANGUAGE ¤È $NAME ¤Ë¤è¤Ã¤Æ
    »ØÄꤵ¤ì¤¿ÆþÎϥ᥽¥Ã¥ÉÍѤÎÆþÎϥ᥽¥Ã¥É¥³¥Þ¥ó¥É $COMMAND ¤ËÂФ·¤Æ¡¢
    ÆþÎÏ¥­¡¼¥·¡¼¥¯¥¨¥ó¥¹ $KEYSEQ ¤ò³ä¤êÅö¤Æ¤ë¡£ $NAME ¤¬ #Mnil ¤Ê¤é¤Ð¡¢
    $LANGUAGE ¤Ë´Ø·¸¤Ê¤¯¡¢ÆþÎÏ¥­¡¼¥·¡¼¥¯¥¨¥ó¥¹¤Ï¥°¥í¡¼¥Ð¥ë¤Ë³ä¤êÅö¤Æ¤é
    ¤ì¤ë¡£¤½¤¦¤Ç¤Ê¤ì¤Ð¡¢³ä¤êÅö¤Æ¤Ï¥í¡¼¥«¥ë¤Ç¤¢¤ë¡£

    $KEYSEQ ¤Î³ÆÍ×ÁǤϥ­¡¼¤È¤·¤Æ $Msymbol ¤ò¡¢ÃͤȤ·¤ÆÆþÎÏ¥­¡¼¤òɽ¤¹¥·
    ¥ó¥Ü¥ë¤ò»ý¤¿¤Ê¤¯¤Æ¤Ï¤Ê¤é¤Ê¤¤¡£

    $KEYSEQ ¤Ï @c NULL ¤Ç¤â¤è¤¤¡£¤³¤Î¾ì¹ç¡¢¥°¥í¡¼¥Ð¥ë¤â¤·¤¯¤Ï¥í¡¼¥«¥ë¤Ê
    ¤¹¤Ù¤Æ¤Î³ä¤êÅö¤Æ¤¬¾Ãµî¤µ¤ì¤ë¡£

    ¤³¤Î³ä¤êÅö¤Æ¤Ï¡¢³ä¤êÅö¤Æ°Ê¹ß¿·¤·¤¯¥ª¡¼¥×¥ó¤µ¤ì¤¿ÆþÎϥ᥽¥Ã¥É¤«¤éÍ­
    ¸ú¤Ë¤Ê¤ë¡£

    @return ½èÍý¤¬À®¸ù¤¹¤ì¤Ð 0 ¤òÊÖ¤¹¡£¤½¤¦¤Ç¤Ê¤±¤ì¤Ð -1 ¤òÊÖ¤·¡¢
    #merror_code ¤ò #MERROR_IM ¤ËÀßÄꤹ¤ë¡£  */

int
minput_assign_command_keys (MSymbol language, MSymbol name,
                            MSymbol command, MPlist *keyseq)
{
  MPlist *plist, *pl, *p;

  if (check_command_keyseq (keyseq) < 0
      || ! (plist = get_nested_list (language, name, Mnil, M_command)))
    MERROR (MERROR_IM, -1);
  pl = mplist_get (plist, command);
  if (pl)
    {
      pl = MPLIST_NEXT (pl);
      if (! keyseq)
        while ((p = mplist_pop (pl)))
          M17N_OBJECT_UNREF (p);
      else
        {
          keyseq = mplist_copy (keyseq);
          mplist_push (pl, Mplist, keyseq);
          M17N_OBJECT_UNREF (keyseq);
        }
    }
  else
    {
      if (name == Mnil)
        MERROR (MERROR_IM, -1);
      if (! keyseq)
        return 0;
      /* Get global commands.  */
      pl = get_nested_list (Mnil, Mnil, Mnil, M_command);
      pl = mplist_get (pl, command);
      if (! pl)
        MERROR (MERROR_IM, -1);
      p = mplist ();
      mplist_add (p, Mtext, mplist_value (pl));
      keyseq = mplist_copy (keyseq);
      mplist_add (p, Mplist, keyseq);
      M17N_OBJECT_UNREF (keyseq);
      mplist_push (plist, command, p);
    }
  return 0;
}

/***en
    @brief Get a list of variables of an input method.

    The minput_get_variables () function returns a plist (#MPlist) of
    variables used to control the behavior of the input method
    specified by $LANGUAGE and $NAME.  The key of an element of the
    plist is a symbol representing a variable, and the value is a
    plist of the form VAR-INFO (described below) that carries the
    information about the variable.

    The first element of VAR-INFO has the key #Mtext or #Msymbol.  If
    the key is #Mtext, the value is an M-text describing the variable.
    If the key is #Msymbol, that value is #Mnil which means the
    variable has no description text.

    The second element of VAR-INFO is for the value of the variable.
    The key is #Minteger, #Msymbol, or #Mtext, and the value is an
    integer, a symbol, or an M-text, respectively.  The variable is
    set to this value when an input context is created for the input
    method.

    If there are no more elements, the variable can take any value
    that matches with the above type.  Otherwise, the remaining
    elements of VAR-INFO are to specify valid values of the variable.

    If the type of the variable is integer, the following elements
    have the key #Minteger or #Mplist.  If it is #Minteger, the value
    is a valid integer value.  If it is #Mplist, the value is a plist
    of two of elements.  Both of them have the key #Minteger, and
    values are the minimum and maximum bounds of the valid value
    range.

    If the type of the variable is symbol or M-text, the following
    elements of the plist have the key #Msymbol or #Mtext,
    respectively, and the value must be a valid one.

    For instance, suppose an input method has the variables:

    @li name:intvar, description:"value is an integer",
         initial value:0, value-range:0..3,10,20

    @li name:symvar, description:"value is a symbol",
         initial value:nil, value-range:a, b, c, nil

    @li name:txtvar, description:"value is an M-text",
         initial value:empty text, no value-range (i.e. any text)

    Then, the returned plist has this form ('X:Y' means X is a key and Y is
    a value, and '(...)' means a plist):

@verbatim
    plist:(intvar:(mtext:"value is an integer"
                   integer:0
                   plist:(integer:0 integer:3)
                   integer:10
                   integer:20))
           symvar:(mtext:"value is a symbol"
                   symbol:nil
                   symbol:a
                   symbol:b
                   symbol:c
                   symbol:nil))
           txtvar:(mtext:"value is an M-text"
                   mtext:""))
@endverbatim

    @return
    If the input method uses any variables, a pointer to #MPlist is
    returned.  As the plist is kept in the library, a caller must not
    modify nor free it.  If the input method does not use any
    variable, @c NULL is returned.  */
/***ja
    @brief ÆþÎϥ᥽¥Ã¥É¤ÎÊÑ¿ô¥ê¥¹¥È¤òÆÀ¤ë.

    ´Ø¿ô minput_get_variables () ¤Ï¡¢$LANGUAGE ¤È $NAME 
    ¤Ë¤è¤Ã¤Æ»ØÄꤵ¤ì¤¿ÆþÎϥ᥽¥Ã¥É¤Î¿¶¤ëÉñ¤¤¤òÀ©¸æ¤¹¤ëÊÑ¿ô¤Î¥×¥í¥Ñ¥Æ¥£¥ê¥¹¥È 
    (#MPlist) ¤òÊÖ¤¹¡£¥ê¥¹¥È¤Î³ÆÍ×ÁǤΥ­¡¼¤ÏÊÑ¿ô¤òɽ¤¹¥·¥ó¥Ü¥ë¤Ç¤¢¤ë¡£
    ³ÆÍ×ÁǤÎÃͤϲ¼µ­¤Î VAR-INFO 
    ¤Î·Á¼°¤Î¥×¥í¥Ñ¥Æ¥£¥ê¥¹¥È¤Ç¤¢¤ê¡¢³ÆÊÑ¿ô¤Ë´Ø¤¹¤ë¾ðÊó¤ò¼¨¤·¤Æ¤¤¤ë¡£

    VAR-INFO ¤ÎÂè°ìÍ×ÁǤΥ­¡¼¤Ï #Mtext ¤Þ¤¿¤Ï #Msymbol ¤Ç¤¢¤ë¡£¥­¡¼¤¬
    #Mtext ¤Ê¤é¡¢ÃͤϤ½¤ÎÊÑ¿ô¤òÀâÌÀ¤¹¤ë M-text ¤Ç¤¢¤ë¡£¥­¡¼¤¬ #Msymbol
    ¤Ê¤éÃÍ¤Ï #Mnil ¤Ç¤¢¤ê¡¢¤³¤ÎÊÑ¿ô¤ÏÀâÌÀ¥Æ¥­¥¹¥È¤ò»ý¤¿¤Ê¤¤¤³¤È¤Ë¤Ê¤ë¡£

    VAR-INFO ¤ÎÂèÆóÍ×ÁǤÏÊÑ¿ô¤ÎÃͤò¼¨¤¹¡£¥­¡¼¤Ï #Minteger, #Msymbol,
    #Mtext ¤Î¤¤¤º¤ì¤«¤Ç¤¢¤ê¡¢ÃͤϤ½¤ì¤¾¤ìÀ°¿ôÃÍ¡¢¥·¥ó¥Ü¥ë¡¢M-text  ¤Ç¤¢¤ë¡£
    ¤³¤ÎÆþÎϥ᥽¥Ã¥ÉÍѤÎÆþÎÏ¥³¥ó¥Æ¥¹¥È¤¬ºî¤é¤ì¤ë»þÅÀ¤Ç¤Ï¡¢ÊÑ¿ô¤Ï¤³¤ÎÃͤËÀßÄꤵ¤ì¤Æ¤¤¤ë¡£

    VAR-INFO ¤Ë¤½¤ì°Ê³°¤ÎÍ×ÁǤ¬Ìµ¤±¤ì¤Ð¡¢ÊÑ¿ô¤Ï¾åµ­¤Î·¿¤Ë¹çÃפ¹¤ë¸Â¤ê¤É¤Î¤è¤¦¤ÊÃͤò¤È¤ë¤³¤È¤â¤Ç¤­¤ë¡£
    ¤½¤¦¤Ç¤Ê¤±¤ì¤Ð¡¢VAR-INFO ¤Î»Ä¤ê¤ÎÍ×ÁǤˤè¤Ã¤ÆÊÑ¿ô¤ÎÍ­¸ú¤ÊÃͤ¬»ØÄꤵ¤ì¤ë¡£

    ÊÑ¿ô¤Î·¿¤¬À°¿ô¤Ç¤¢¤ì¤Ð¡¢¤½¤ì°Ê¹ß¤ÎÍ×ÁÇ¤Ï #Minteger ¤« #Mplist 
    ¤ò¥­¡¼¤È¤·¤Æ»ý¤Ä¡£ #Minteger ¤Ç¤¢¤ì¤Ð¡¢ÃͤÏÍ­¸ú¤ÊÃͤò¼¨¤¹À°¿ôÃͤǤ¢¤ë¡£
    #Mplist ¤Ç¤¢¤ì¤Ð¡¢ÃͤÏÆó¤Ä¤ÎÍ×ÁǤò»ý¤Ä¥×¥í¥Ñ¥Æ¥£¥ê¥¹¥È¤Ç¤¢¤ê¡¢³ÆÍ×ÁǤϥ­¡¼¤È¤·¤Æ
    #Minteger ¤ò¡¢ÃͤȤ·¤Æ¤½¤ì¤¾¤ìÍ­¸ú¤ÊÃͤξå¸ÂÃͤȲ¼¸ÂÃͤò¤È¤ë¡£

    ÊÑ¿ô¤Î·¿¤¬¥·¥ó¥Ü¥ë¤« M-text ¤Ç¤¢¤ì¤Ð¡¢¤½¤ì°Ê¹ß¤ÎÍ×ÁǤϥ­¡¼¤È¤·¤Æ¤½¤ì¤¾¤ì
    #Msymbol ¤« #Mtext ¤ò»ý¤Á¡¢ÃͤϤ½¤Î·¿¤Ë¹çÃפ¹¤ë¤â¤Î¤Ç¤¢¤ë¡£

    Îã¤È¤·¤Æ¡¢¤¢¤ëÆþÎϥ᥽¥Ã¥É¤¬¼¡¤Î¤è¤¦¤ÊÊÑ¿ô¤ò»ý¤Ä¾ì¹ç¤ò¹Í¤¨¤è¤¦¡£

    @li name:intvar, ÀâÌÀ:"value is an integer",
        ½é´üÃÍ:0, ÃͤÎÈÏ°Ï:0..3,10,20

    @li name:symvar, ÀâÌÀ:"value is a symbol",
         ½é´üÃÍ:nil, ÃͤÎÈÏ°Ï:a, b, c, nil

    @li name:txtvar, ÀâÌÀ:"value is an M-text",
        ½é´üÃÍ:empty text, ÃͤÎÈϰϤʤ·(¤É¤ó¤Ê M-text ¤Ç¤â²Ä)

    ¤³¤Î¾ì¹ç¡¢ÊÖ¤µ¤ì¤ë¥ê¥¹¥È¤Ï°Ê²¼¤Î¤è¤¦¤Ë¤Ê¤ë¡£¡Ê'X:Y' ¤È¤¤¤¦µ­Ë¡¤Ï X 
    ¤¬¥­¡¼¤Ç Y ¤¬ÃͤǤ¢¤ë¤³¤È¤ò¡¢¤Þ¤¿ '(...)' ¤Ï¥×¥í¥Ñ¥Æ¥£¥ê¥¹¥È¤ò¼¨¤¹¡£¡Ë

@verbatim
    plist:(intvar:(mtext:"value is an integer"
                   integer:0
                   plist:(integer:0 integer:3)
                   integer:10
                   integer:20))
           symvar:(mtext:"value is a symbol"
                   symbol:nil
                   symbol:a
                   symbol:b
                   symbol:c
                   symbol:nil))
           txtvar:(mtext:"value is an M-text"
                   mtext:""))
@endverbatim

    @return 
    ÆþÎϥ᥽¥Ã¥É¤¬²¿¤é¤«¤ÎÊÑ¿ô¤ò»ÈÍѤ·¤Æ¤¤¤ì¤Ð #MPlist ¤Ø¤ÎÊÑ¿ô¤òÊÖ¤¹¡£
    ÊÖ¤µ¤ì¤ë¥×¥í¥Ñ¥Æ¥£¥ê¥¹¥È¤Ï¥é¥¤¥Ö¥é¥ê¤Ë¤è¤Ã¤Æ´ÉÍý¤µ¤ì¤Æ¤ª¤ê¡¢¸Æ¤Ó½Ð¤·Â¦¤ÇÊѹ¹¤·¤¿¤ê²òÊü¤·¤¿¤ê¤·¤Æ¤Ï¤Ê¤é¤Ê¤¤¡£
    ÆþÎϥ᥽¥Ã¥É¤¬ÊÑ¿ô¤ò°ìÀÚ»ÈÍѤ·¤Æ¤Ê¤±¤ì¤Ð¡¢@c NULL ¤òÊÖ¤¹¡£  */

MPlist *
minput_get_variables (MSymbol language, MSymbol name)
{
  MPlist *plist = get_nested_list (language, name, Mnil, M_variable);

  return (MPLIST_TAIL_P (plist) ? NULL : plist);
}

/***en
    @brief Set the initial value of an input method variable.

    The minput_set_variable () function sets the initial value of
    input method variable $VARIABLE to $VALUE for the input method
    specified by $LANGUAGE and $NAME.

    By default, the initial value is 0.

    This setting gets effective in a newly opened input method.

    @return
    If the operation was successful, 0 is returned.  Otherwise -1 is
    returned, and #merror_code is set to #MERROR_IM.  */
/***ja
    @brief ÆþÎϥ᥽¥Ã¥ÉÊÑ¿ô¤Î½é´üÃͤòÀßÄꤹ¤ë.

    ´Ø¿ô minput_set_variable () ¤Ï¡¢$LANGUAGE ¤È $NAME 
    ¤Ë¤è¤Ã¤Æ»ØÄꤵ¤ì¤¿ÆþÎϥ᥽¥Ã¥É¤ÎÆþÎϥ᥽¥Ã¥ÉÊÑ¿ô $VARIABLE
    ¤Î½é´üÃͤò¡¢ $VALUE ¤ËÀßÄꤹ¤ë¡£

    ¥Ç¥Õ¥©¥ë¥È¤Î½é´üÃÍ¤Ï 0 ¤Ç¤¢¤ë¡£

    ¤³¤ÎÀßÄê¤Ï¡¢¿·¤·¤¯¥ª¡¼¥×¥ó¤µ¤ì¤¿ÆþÎϥ᥽¥Ã¥É¤«¤éÍ­¸ú¤È¤Ê¤ë¡£

    @return
    ½èÍý¤¬À®¸ù¤¹¤ì¤Ð 0 ¤òÊÖ¤¹¡£¤½¤¦¤Ç¤Ê¤±¤ì¤Ð -1 ¤òÊÖ¤·¡¢
    #merror_code ¤ò #MERROR_IM ¤ËÀßÄꤹ¤ë¡£  */

int
minput_set_variable (MSymbol language, MSymbol name,
                     MSymbol variable, void *value)
{
  MPlist *plist, *val_element, *range_element;
  MSymbol type;

  plist = get_nested_list (language, name, Mnil, M_variable);
  if (! plist)
    MERROR (MERROR_IM, -1);
  plist = mplist_find_by_value (plist, variable);
  if (! plist)
    MERROR (MERROR_IM, -1);
  plist = MPLIST_PLIST (MPLIST_NEXT (plist));
  val_element = MPLIST_NEXT (plist);
  type = MPLIST_KEY (val_element);
  range_element = MPLIST_NEXT (val_element);
    
  if (! MPLIST_TAIL_P (range_element))
    {
      if (type == Minteger)
        {
          int val = (int) value, this_val;
      
          MPLIST_DO (plist, range_element)
            {
              this_val = (int) MPLIST_VAL (plist);
              if (MPLIST_PLIST_P (plist))
                {
                  int min_bound, max_bound;
                  MPlist *pl = MPLIST_PLIST (plist);

                  min_bound = (int) MPLIST_VAL (pl);
                  pl = MPLIST_NEXT (pl);
                  max_bound = (int) MPLIST_VAL (pl);
                  if (val >= min_bound && val <= max_bound)
                    break;
                }
              else if (val == this_val)
                break;
            }
          if (MPLIST_TAIL_P (plist))
            MERROR (MERROR_IM, -1);
        }
      else if (type == Msymbol)
        {
          MPLIST_DO (plist, range_element)
            if (MPLIST_SYMBOL (plist) == (MSymbol) value)
              break;
          if (MPLIST_TAIL_P (plist))
            MERROR (MERROR_IM, -1);
        }
      else                      /* type == Mtext */
        {
          MPLIST_DO (plist, range_element)
            if (mtext_cmp (MPLIST_MTEXT (plist), (MText *) value) == 0)
              break;
          if (MPLIST_TAIL_P (plist))
            MERROR (MERROR_IM, -1);
          M17N_OBJECT_REF (value);
        }
    }

  mplist_set (val_element, type, value);
  return 0;
}

/*** @} */
/*=*/
/*** @addtogroup m17nDebug */
/*=*/
/*** @{  */
/*=*/

/***en
    @brief Dump an input method.

    The mdebug_dump_im () function prints the input method $IM in a
    human readable way to the stderr.  $INDENT specifies how many
    columns to indent the lines but the first one.

    @return
    This function returns $IM.  */
/***ja
    @brief ÆþÎϥ᥽¥Ã¥É¤ò¥À¥ó¥×¤¹¤ë.

    ´Ø¿ô mdebug_dump_im () ¤ÏÆþÎϥ᥽¥Ã¥É $IM ¤ò stderr 
    ¤Ë¿Í´Ö¤Ë²ÄÆɤʷÁ¤Ç°õºþ¤¹¤ë¡£$INDENT ¤Ï£²¹ÔÌܰʹߤΥ¤¥ó¥Ç¥ó¥È¤ò»ØÄꤹ¤ë¡£

    @return
    ¤³¤Î´Ø¿ô¤Ï $IM ¤òÊÖ¤¹¡£  */

MInputMethod *
mdebug_dump_im (MInputMethod *im, int indent)
{
  MInputMethodInfo *im_info = (MInputMethodInfo *) im->info;
  char *prefix;

  prefix = (char *) alloca (indent + 1);
  memset (prefix, 32, indent);
  prefix[indent] = '\0';

  fprintf (stderr, "(input-method %s %s ", msymbol_name (im->language),
           msymbol_name (im->name));
  mdebug_dump_mtext (im_info->title, 0, 0);
  if (im->name != Mnil)
    {
      MPlist *state;

      MPLIST_DO (state, im_info->states)
        {
          fprintf (stderr, "\n%s  ", prefix);
          dump_im_state (MPLIST_VAL (state), indent + 2);
        }
    }
  fprintf (stderr, ")");
  return im;
}

/*** @} */ 

/*
  Local Variables:
  coding: euc-japan
  End:
*/