path: root/libempathy-gtk/empathy-spell.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
 * Copyright (C) 2004-2007 Imendio AB
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
 * Boston, MA  02110-1301  USA
 *
 * Authors: Martyn Russell <martyn@imendio.com>
 *          Richard Hult <richard@imendio.com>
 */

#include "config.h"

#include <string.h>
#include <stdlib.h>

#include <glib/gi18n-lib.h>

#ifdef HAVE_ENCHANT
#include <enchant.h>
#endif

#include "empathy-spell.h"

#define DEBUG_FLAG EMPATHY_DEBUG_OTHER
#include <libempathy/empathy-debug.h>
#include <libempathy/empathy-gsettings.h>

#ifdef HAVE_ENCHANT

typedef struct {
    EnchantBroker *config;
    EnchantDict   *speller;
} SpellLanguage;

#define ISO_CODES_DATADIR    ISO_CODES_PREFIX "/share/xml/iso-codes"
#define ISO_CODES_LOCALESDIR ISO_CODES_PREFIX "/share/locale"

/* Language code (gchar *) -> language name (gchar *) */
static GHashTable  *iso_code_names = NULL;
/* Contains only _enabled_ languages
 * Language code (gchar *) -> language (SpellLanguage *) */
static GHashTable  *languages = NULL;

static void
spell_iso_codes_parse_start_tag (GMarkupParseContext  *ctx,
                 const gchar          *element_name,
                 const gchar         **attr_names,
                 const gchar         **attr_values,
                 gpointer              data,
                 GError              **error)
{
    const gchar *ccode_longB, *ccode_longT, *ccode;
    const gchar *lang_name;

    if (!g_str_equal (element_name, "iso_639_entry") ||
        attr_names == NULL || attr_values == NULL) {
        return;
    }

    ccode = NULL;
    ccode_longB = NULL;
    ccode_longT = NULL;
    lang_name = NULL;

    while (*attr_names && *attr_values) {
        if (g_str_equal (*attr_names, "iso_639_1_code")) {
            if (**attr_values) {
                ccode = *attr_values;
            }
        }
        else if (g_str_equal (*attr_names, "iso_639_2B_code")) {
            if (**attr_values) {
                ccode_longB = *attr_values;
            }
        }
        else if (g_str_equal (*attr_names, "iso_639_2T_code")) {
            if (**attr_values) {
                ccode_longT = *attr_values;
            }
        }
        else if (g_str_equal (*attr_names, "name")) {
            lang_name = *attr_values;
        }

        attr_names++;
        attr_values++;
    }

    if (!lang_name) {
        return;
    }

    if (ccode) {
        g_hash_table_insert (iso_code_names,
                     g_strdup (ccode),
                     g_strdup (lang_name));
    }

    if (ccode_longB) {
        g_hash_table_insert (iso_code_names,
                     g_strdup (ccode_longB),
                     g_strdup (lang_name));
    }

    if (ccode_longT) {
        g_hash_table_insert (iso_code_names,
                     g_strdup (ccode_longT),
                     g_strdup (lang_name));
    }
}

static void
spell_iso_code_names_init (void)
{
    GError *err = NULL;
    gchar  *buf;
    gsize   buf_len;

    iso_code_names = g_hash_table_new_full (g_str_hash, g_str_equal,
                        g_free, g_free);

    bindtextdomain ("iso_639", ISO_CODES_LOCALESDIR);
    bind_textdomain_codeset ("iso_639", "UTF-8");

    /* FIXME: We should read this in chunks and pass to the parser. */
    if (g_file_get_contents (ISO_CODES_DATADIR "/iso_639.xml", &buf, &buf_len, &err)) {
        GMarkupParseContext *ctx;
        GMarkupParser        parser = {
            spell_iso_codes_parse_start_tag,
            NULL, NULL, NULL, NULL
        };

        ctx = g_markup_parse_context_new (&parser, 0, NULL, NULL);
        if (!g_markup_parse_context_parse (ctx, buf, buf_len, &err)) {
            g_warning ("Failed to parse '%s': %s",
                   ISO_CODES_DATADIR"/iso_639.xml",
                   err->message);
            g_error_free (err);
        }

        g_markup_parse_context_free (ctx);
        g_free (buf);
    } else {
        g_warning ("Failed to load '%s': %s",
                ISO_CODES_DATADIR"/iso_639.xml", err->message);
        g_error_free (err);
    }
}

static void
spell_notify_languages_cb (GSettings   *gsettings,
               const gchar *key,
               gpointer     user_data)
{
    DEBUG ("Resetting languages due to config change");

    /* We just reset the languages list. */
    if (languages != NULL) {
        g_hash_table_unref (languages);
        languages = NULL;
    }
}

static void
empathy_spell_free_language (SpellLanguage *lang)
{
    enchant_broker_free_dict (lang->config, lang->speller);
    enchant_broker_free (lang->config);

    g_slice_free (SpellLanguage, lang);
}

static void
spell_setup_languages (void)
{
    static GSettings *gsettings = NULL;
    gchar  *str;

    if (gsettings == NULL) {
        /* FIXME: this is never uninitialised */
        gsettings = g_settings_new (EMPATHY_PREFS_CHAT_SCHEMA);

        g_signal_connect (gsettings,
            "changed::" EMPATHY_PREFS_CHAT_SPELL_CHECKER_LANGUAGES,
            G_CALLBACK (spell_notify_languages_cb), NULL);
    }

    if (languages) {
        return;
    }

    languages = g_hash_table_new_full (g_str_hash, g_str_equal,
            g_free, (GDestroyNotify) empathy_spell_free_language);

    str = g_settings_get_string (gsettings,
            EMPATHY_PREFS_CHAT_SPELL_CHECKER_LANGUAGES);

    if (str != NULL) {
        gchar **strv;
        gint    i;

        strv = g_strsplit (str, ",", -1);

        i = 0;
        while (strv && strv[i]) {
            SpellLanguage *lang;

            DEBUG ("Setting up language:'%s'", strv[i]);

            lang = g_slice_new0 (SpellLanguage);

            lang->config = enchant_broker_init ();
            lang->speller = enchant_broker_request_dict (lang->config, strv[i]);

            if (lang->speller == NULL) {
                DEBUG ("language '%s' has no valid dict", strv[i]);
            } else {
                g_hash_table_insert (languages,
                             g_strdup (strv[i]),
                             lang);
            }

            i++;
        }

        if (strv) {
            g_strfreev (strv);
        }

        g_free (str);
    }
}

const gchar *
empathy_spell_get_language_name (const gchar *code)
{
    const gchar *name;

    g_return_val_if_fail (code != NULL, NULL);

    if (!iso_code_names) {
        spell_iso_code_names_init ();
    }

    name = g_hash_table_lookup (iso_code_names, code);
    if (!name) {
        return NULL;
    }

    return dgettext ("iso_639", name);
}

static void
enumerate_dicts (const gchar * const lang_tag,
                 const gchar * const provider_name,
                 const gchar * const provider_desc,
                 const gchar * const provider_file,
         gpointer            user_data)
{
    GList **list = user_data;
    gchar  *lang = g_strdup (lang_tag);

    if (strchr (lang, '_')) {
        /* cut country part out of language */
        strchr (lang, '_')[0] = '\0';
    }

    if (g_list_find_custom (*list, lang, (GCompareFunc) strcmp)) {
        /* this language is already part of the list */
        g_free (lang);
        return;
    }

    *list = g_list_append (*list, lang);
}

GList *
empathy_spell_get_language_codes (void)
{
    EnchantBroker *broker;
    GList         *list_langs = NULL;

    broker = enchant_broker_init ();
    enchant_broker_list_dicts (broker, enumerate_dicts, &list_langs);
    enchant_broker_free (broker);

    return list_langs;
}

GList *
empathy_spell_get_enabled_language_codes (void)
{
    spell_setup_languages ();
    return g_hash_table_get_keys (languages);
}

void
empathy_spell_free_language_codes (GList *codes)
{
    g_list_foreach (codes, (GFunc) g_free, NULL);
    g_list_free (codes);
}

gboolean
empathy_spell_check (const gchar *word)
{
    gint         enchant_result = 1;
    const gchar *p;
    gboolean     digit;
    gunichar     c;
    gint         len;
    GHashTableIter iter;
    SpellLanguage  *lang;

    g_return_val_if_fail (word != NULL, FALSE);

    spell_setup_languages ();

    if (!languages) {
        return TRUE;
    }

    /* Ignore certain cases like numbers, etc. */
    for (p = word, digit = TRUE; *p && digit; p = g_utf8_next_char (p)) {
        c = g_utf8_get_char (p);
        digit = g_unichar_isdigit (c);
    }

    if (digit) {
        /* We don't spell check digits. */
        DEBUG ("Not spell checking word:'%s', it is all digits", word);
        return TRUE;
    }

    len = strlen (word);
    g_hash_table_iter_init (&iter, languages);
    while (g_hash_table_iter_next (&iter, NULL, (gpointer *) &lang)) {
        enchant_result = enchant_dict_check (lang->speller, word, len);

        if (enchant_result == 0) {
            break;
        }
    }

    return (enchant_result == 0);
}

GList *
empathy_spell_get_suggestions (const gchar *code,
                   const gchar *word)
{
    gint   len;
    GList *suggestion_list = NULL;
    SpellLanguage *lang;
    gchar **suggestions;
    gsize   i, number_of_suggestions;

    g_return_val_if_fail (code != NULL, NULL);
    g_return_val_if_fail (word != NULL, NULL);

    spell_setup_languages ();

    if (!languages) {
        return NULL;
    }

    len = strlen (word);

    lang = g_hash_table_lookup (languages, code);
    if (!lang) {
        return NULL;
    }

    suggestions = enchant_dict_suggest (lang->speller, word, len,
                        &number_of_suggestions);

    for (i = 0; i < number_of_suggestions; i++) {
        suggestion_list = g_list_append (suggestion_list,
                         g_strdup (suggestions[i]));
    }

    if (suggestions) {
        enchant_dict_free_string_list (lang->speller, suggestions);
    }

    return suggestion_list;
}

gboolean
empathy_spell_supported (void)
{
    if (g_getenv ("EMPATHY_SPELL_DISABLED")) {
        DEBUG ("EMPATHY_SPELL_DISABLE env variable defined");
        return FALSE;
    }

    return TRUE;
}

void
empathy_spell_add_to_dictionary (const gchar *code,
                 const gchar *word)
{
    SpellLanguage *lang;

    g_return_if_fail (code != NULL);
    g_return_if_fail (word != NULL);

    spell_setup_languages ();
    if (languages == NULL)
        return;

    lang = g_hash_table_lookup (languages, code);
    if (lang == NULL)
        return;

    enchant_dict_add_to_pwl (lang->speller, word, strlen (word));
}

#else /* not HAVE_ENCHANT */

gboolean
empathy_spell_supported (void)
{
    return FALSE;
}

GList *
empathy_spell_get_suggestions (const gchar *code,
                               const gchar *word)
{
    DEBUG ("Support disabled, could not get suggestions");

    return NULL;
}

gboolean
empathy_spell_check (const gchar *word)
{
    DEBUG ("Support disabled, could not check spelling");

    return TRUE;
}

const gchar *
empathy_spell_get_language_name (const gchar *lang)
{
    DEBUG ("Support disabled, could not get language name");

    return NULL;
}

GList *
empathy_spell_get_language_codes (void)
{
    DEBUG ("Support disabled, could not get language codes");

    return NULL;
}

void
empathy_spell_free_language_codes (GList *codes)
{
}

void
empathy_spell_add_to_dictionary (const gchar *code,
                 const gchar *word)
{
    DEBUG ("Support disabled, could not expand the dictionary");
}

GList *
empathy_spell_get_enabled_language_codes (void)
{
    DEBUG ("Support disabled, could not get enabled language codes");

    return NULL;
}

#endif /* HAVE_ENCHANT */


void
empathy_spell_free_suggestions (GList *suggestions)
{
    g_list_foreach (suggestions, (GFunc) g_free, NULL);
    g_list_free (suggestions);
}