/* -*- mode: C; c-basic-offset: 4; indent-tabs-mode: nil; -*- */

/* vim:set et sts=4: */

/* ibus - The Input Bus

 * Copyright (C) 2008-2013 Peng Huang <shawn.p.huang@gmail.com>

 * Copyright (C) 2011-2018 Takao Fujiwara <takao.fujiwara1@gmail.com>

 * Copyright (C) 2008-2018 Red Hat, Inc.

 *

 * This 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.

 *

 * This 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 this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301

 * USA

 */

#include "ibusimpl.h"

#include <locale.h>

#include <signal.h>

#include <strings.h>

#include <sys/types.h>

#include <sys/wait.h>

#include <unistd.h>

#include "connection.h"

#include "dbusimpl.h"

#include "factoryproxy.h"

#include "global.h"

#include "inputcontext.h"

#include "panelproxy.h"

#include "server.h"

#include "types.h"

struct _BusIBusImpl {

    IBusService parent;

    /* instance members */

    GHashTable *factory_dict;

    /* registered components */

    GList *registered_components;

    GList *contexts;

    /* a fake input context for global engine support */

    BusInputContext *fake_context;

    /* a list of engines that are started by a user (without the --ibus

     * command line flag.) */

    GList *register_engine_list;

    /* if TRUE, ibus-daemon uses a keysym translated by the system

     * (i.e. XKB) as-is. otherwise, ibus-daemon itself converts keycode

     * into keysym. */

    gboolean use_sys_layout;

    gboolean embed_preedit_text;

    IBusRegistry    *registry;

    /* a list of BusComponent objects that are created from component XML

     * files (or from the cache of them). */

    GList *components;

    /* a mapping from an engine name (e.g. 'pinyin') to the corresponding

     * IBusEngineDesc object. */

    GHashTable *engine_table;

    BusInputContext *focused_context;

    BusPanelProxy   *panel;

    BusPanelProxy   *emoji_extension;

    gboolean         enable_emoji_extension;

    /* a default keymap of ibus-daemon (usually "us") which is used only

     * when use_sys_layout is FALSE. */

    IBusKeymap      *keymap;

    gboolean use_global_engine;

    gchar *global_engine_name;

    gchar *global_previous_engine_name;

    GVariant *extension_register_keys;

};

struct _BusIBusImplClass {

    IBusServiceClass parent;

    /* class members */

};

enum {

    LAST_SIGNAL,

};

enum {

    PROP_0,

};

/*

static guint            _signals[LAST_SIGNAL] = { 0 };

*/

/* functions prototype */

static void     bus_ibus_impl_destroy   (BusIBusImpl        *ibus);

static void     bus_ibus_impl_service_method_call

                                        (IBusService        *service,

                                         GDBusConnection    *connection,

                                         const gchar        *sender,

                                         const gchar        *object_path,

                                         const gchar        *interface_name,

                                         const gchar        *method_name,

                                         GVariant           *parameters,

                                         GDBusMethodInvocation

                                                            *invocation);

static GVariant *

                bus_ibus_impl_service_get_property

                                        (IBusService        *service,

                                         GDBusConnection    *connection,

                                         const gchar        *sender,

                                         const gchar        *object_path,

                                         const gchar        *interface_name,

                                         const gchar        *property_name,

                                         GError            **error);

static gboolean

                bus_ibus_impl_service_set_property

                                        (IBusService        *service,

                                         GDBusConnection    *connection,

                                         const gchar        *sender,

                                         const gchar        *object_path,

                                         const gchar        *interface_name,

                                         const gchar        *property_name,

                                         GVariant           *value,

                                         GError            **error);

static void     bus_ibus_impl_registry_init

                                        (BusIBusImpl        *ibus);

static void     bus_ibus_impl_registry_changed

                                        (BusIBusImpl        *ibus);

static void     bus_ibus_impl_registry_destroy

                                        (BusIBusImpl        *ibus);

static void     bus_ibus_impl_component_name_owner_changed

                                        (BusIBusImpl        *ibus,

                                         const gchar        *name,

                                         const gchar        *old_name,

                                         const gchar        *new_name);

static void     bus_ibus_impl_global_engine_changed

                                        (BusIBusImpl        *ibus);

static void     bus_ibus_impl_set_context_engine_from_desc

                                        (BusIBusImpl        *ibus,

                                         BusInputContext    *context,

                                         IBusEngineDesc     *desc);

static BusInputContext

               *bus_ibus_impl_create_input_context

                                        (BusIBusImpl        *ibus,

                                         BusConnection      *connection,

                                         const gchar        *client);

static IBusEngineDesc

               *bus_ibus_impl_get_engine_desc

                                        (BusIBusImpl        *ibus,

                                         const gchar        *engine_name);

static void     bus_ibus_impl_set_focused_context

                                        (BusIBusImpl        *ibus,

                                         BusInputContext    *context);

static void     bus_ibus_impl_property_changed

                                        (BusIBusImpl        *service,

                                         const gchar        *property_name,

                                         GVariant           *value);

/* some callback functions */

static void     _context_engine_changed_cb

                                        (BusInputContext    *context,

                                         BusIBusImpl        *ibus);

/* The interfaces available in this class, which consists of a list of

 * methods this class implements and a list of signals this class may emit.

 * Method calls to the interface that are not defined in this XML will

 * be automatically rejected by the GDBus library (see src/ibusservice.c

 * for details.)

 * Implement org.freedesktop.DBus.Properties

 * http://dbus.freedesktop.org/doc/dbus-specification.html#standard-interfaces-properties */

static const gchar introspection_xml[] =

    "<node>\n"

    "  <interface name='org.freedesktop.IBus'>\n"

    "    <property name='Address' type='s' access='read' />\n"

    "    <property name='CurrentInputContext' type='o' access='read' />\n"

    "    <property name='Engines' type='av' access='read' />\n"

    "    <property name='GlobalEngine' type='v' access='read' />\n"

    "    <property name='PreloadEngines' type='as' access='write'>\n"

    "      

    "          name='org.freedesktop.DBus.Property.EmitsChangedSignal'\n"

    "          value='true' />\n"

    "    </property>\n"

    "    <property name='EmbedPreeditText' type='b' access='readwrite'>\n"

    "      

    "          name='org.freedesktop.DBus.Property.EmitsChangedSignal'\n"

    "          value='true' />\n"

    "    </property>\n"

    "    <method name='CreateInputContext'>\n"

    "      <arg direction='in'  type='s' name='client_name' />\n"

    "      <arg direction='out' type='o' name='object_path' />\n"

    "    </method>\n"

    "    <method name='RegisterComponent'>\n"

    "      <arg direction='in'  type='v' name='component' />\n"

    "    </method>\n"

    "    <method name='GetEnginesByNames'>\n"

    "      <arg direction='in'  type='as' name='names' />\n"

    "      <arg direction='out' type='av' name='engines' />\n"

    "    </method>\n"

    "    <method name='Exit'>\n"

    "      <arg direction='in'  type='b' name='restart' />\n"

    "    </method>\n"

    "    <method name='Ping'>\n"

    "      <arg direction='in'  type='v' name='data' />\n"

    "      <arg direction='out' type='v' name='data' />\n"

    "    </method>\n"

    "    <method name='SetGlobalEngine'>\n"

    "      <arg direction='in'  type='s' name='engine_name' />\n"

    "    </method>\n"

    "    <signal name='RegistryChanged'>\n"

    "    </signal>\n"

    "    <signal name='GlobalEngineChanged'>\n"

    "      <arg type='s' name='engine_name' />\n"

    "    </signal>\n"

    "    <property name='ActiveEngines' type='av' access='read' />\n"

    "    <method name='GetAddress'>\n"

    "      <arg direction='out' type='s' name='address' />\n"

    "      <annotation name='org.freedesktop.DBus.Deprecated' value='true'/>\n"

    "    </method>\n"

    "    <method name='CurrentInputContext'>\n"

    "      <arg direction='out' type='o' name='object_path' />\n"

    "      <annotation name='org.freedesktop.DBus.Deprecated' value='true'/>\n"

    "    </method>\n"

    "    <method name='ListEngines'>\n"

    "      <arg direction='out' type='av' name='engines' />\n"

    "      <annotation name='org.freedesktop.DBus.Deprecated' value='true'/>\n"

    "    </method>\n"

    "    <method name='ListActiveEngines'>\n"

    "      <arg direction='out' type='av' name='engines' />\n"

    "      <annotation name='org.freedesktop.DBus.Deprecated' value='true'/>\n"

    "    </method>\n"

    "    <method name='GetUseSysLayout'>\n"

    "      <arg direction='out' type='b' name='enabled' />\n"

    "      <annotation name='org.freedesktop.DBus.Deprecated' value='true'/>\n"

    "    </method>\n"

    "    <method name='GetUseGlobalEngine'>\n"

    "      <arg direction='out' type='b' name='enabled' />\n"

    "    </method>\n"

    "    <method name='IsGlobalEngineEnabled'>\n"

    "      <arg direction='out' type='b' name='enabled' />\n"

    "      <annotation name='org.freedesktop.DBus.Deprecated' value='true'/>\n"

    "    </method>\n"

    "    <method name='GetGlobalEngine'>\n"

    "      <arg direction='out' type='v' name='desc' />\n"

    "      <annotation name='org.freedesktop.DBus.Deprecated' value='true'/>\n"

    "    </method>\n"

    "  </interface>\n"

    "</node>\n";

G_DEFINE_TYPE (BusIBusImpl, bus_ibus_impl, IBUS_TYPE_SERVICE)

static void

bus_ibus_impl_class_init (BusIBusImplClass *class)

{

    IBUS_OBJECT_CLASS (class)->destroy =

            (IBusObjectDestroyFunc) bus_ibus_impl_destroy;

    /* override the parent class's implementation. */

    IBUS_SERVICE_CLASS (class)->service_method_call =

            bus_ibus_impl_service_method_call;

    IBUS_SERVICE_CLASS (class)->service_get_property =

            bus_ibus_impl_service_get_property;

    IBUS_SERVICE_CLASS (class)->service_set_property =

            bus_ibus_impl_service_set_property;

    /* register the xml so that bus_ibus_impl_service_method_call will be

     * called on a method call defined in the xml (e.g. 'GetAddress'.) */

    ibus_service_class_add_interfaces (IBUS_SERVICE_CLASS (class),

                                       introspection_xml);

}

/**

 * _panel_destroy_cb:

 *

 * A callback function which is called when (1) the connection to the panel process is terminated,

 * or (2) ibus_proxy_destroy (ibus->panel); is called. See src/ibusproxy.c for details.

 */

static void

_panel_destroy_cb (BusPanelProxy *panel,

                   BusIBusImpl   *ibus)

{

    g_assert (BUS_IS_PANEL_PROXY (panel));

    g_assert (BUS_IS_IBUS_IMPL (ibus));

    if (ibus->panel == panel)

        ibus->panel = NULL;

    else if (ibus->emoji_extension == panel)

        ibus->emoji_extension = NULL;

    else

        g_return_if_reached ();

    g_object_unref (panel);

}

static void

bus_ibus_impl_set_panel_extension_mode (BusIBusImpl        *ibus,

                                        IBusExtensionEvent *event)

{

    gboolean is_extension = FALSE;

    g_return_if_fail (BUS_IS_IBUS_IMPL (ibus));

    g_return_if_fail (IBUS_IS_EXTENSION_EVENT (event));

    if (!ibus->emoji_extension) {

        g_warning ("Panel extension is not running.");

        return;

    }

    g_return_if_fail (BUS_IS_PANEL_PROXY (ibus->emoji_extension));

    ibus->enable_emoji_extension = ibus_extension_event_is_enabled (event);

    is_extension = ibus_extension_event_is_extension (event);

    if (ibus->focused_context != NULL) {

        if (ibus->enable_emoji_extension) {

            bus_input_context_set_emoji_extension (ibus->focused_context,

                                                   ibus->emoji_extension);

        } else {

            bus_input_context_set_emoji_extension (ibus->focused_context, NULL);

        }

        if (is_extension)

            bus_input_context_panel_extension_received (ibus->focused_context,

                                                        event);

    }

    if (is_extension)

        return;

    /* Use the DBus method because it seems any DBus signal,

     * g_dbus_message_new_signal(), cannot be reached to the server. */

    bus_panel_proxy_panel_extension_received (ibus->emoji_extension,

                                              event);

}

static void

bus_ibus_impl_set_panel_extension_keys (BusIBusImpl *ibus,

                                        GVariant    *parameters)

{

    BusEngineProxy *engine = NULL;

    g_return_if_fail (BUS_IS_IBUS_IMPL (ibus));

    g_return_if_fail (parameters);

    if (!ibus->emoji_extension) {

        g_warning ("Panel extension is not running.");

        return;

    }

    if (ibus->extension_register_keys)

        g_variant_unref (ibus->extension_register_keys);

    ibus->extension_register_keys = g_variant_ref_sink (parameters);

    if (ibus->focused_context != NULL) {

            engine = bus_input_context_get_engine (ibus->focused_context);

    }

    if (!engine)

        return;

    bus_engine_proxy_panel_extension_register_keys (engine, parameters);

}

static void

_panel_panel_extension_cb (BusPanelProxy      *panel,

                           IBusExtensionEvent *event,

                           BusIBusImpl        *ibus)

{

    bus_ibus_impl_set_panel_extension_mode (ibus, event);

}

static void

_panel_panel_extension_register_keys_cb (BusInputContext *context,

                                         GVariant        *parameters,

                                         BusIBusImpl     *ibus)

{

    bus_ibus_impl_set_panel_extension_keys (ibus, parameters);

}

static void

_panel_update_preedit_text_received_cb (BusPanelProxy *panel,

                                        IBusText      *text,

                                        guint          cursor_pos,

                                        gboolean       visible,

                                        BusIBusImpl   *ibus)

{

    g_return_if_fail (BUS_IS_IBUS_IMPL (ibus));

    if (!ibus->focused_context)

        return;

    bus_input_context_update_preedit_text (ibus->focused_context,

        text, cursor_pos, visible, IBUS_ENGINE_PREEDIT_CLEAR, FALSE);

}

static void

_panel_update_lookup_table_received_cb (BusPanelProxy   *panel,

                                        IBusLookupTable *table,

                                        gboolean         visible,

                                        BusIBusImpl     *ibus)

{

    g_return_if_fail (BUS_IS_IBUS_IMPL (ibus));

    g_return_if_fail (IBUS_IS_LOOKUP_TABLE (table));

    if (!ibus->focused_context)

        return;

    /* Call bus_input_context_update_lookup_table() instead of

     * bus_panel_proxy_update_lookup_table() for panel extensions because

     * bus_input_context_page_up() can call bus_panel_proxy_page_up_received().

     */

    bus_input_context_update_lookup_table (

            ibus->focused_context, table, visible, TRUE);

}

static void

_panel_update_auxiliary_text_received_cb (BusPanelProxy *panel,

                                          IBusText      *text,

                                          gboolean       visible,

                                          BusIBusImpl   *ibus)

{

    g_return_if_fail (BUS_IS_IBUS_IMPL (ibus));

    g_return_if_fail (IBUS_IS_TEXT (text));

    if (!ibus->panel)

        return;

    bus_panel_proxy_update_auxiliary_text (

            ibus->panel, text, visible);

}

static void

_registry_changed_cb (IBusRegistry *registry,

                      BusIBusImpl  *ibus)

{

    bus_ibus_impl_registry_changed (ibus);

}

/*

 * _dbus_name_owner_changed_cb:

 *

 * A callback function to be called when the name-owner-changed signal is sent to the dbus object.

 * This usually means a client (e.g. a panel/config/engine process or an application) is connected/disconnected to/from the bus.

 */

static void

_dbus_name_owner_changed_cb (BusDBusImpl   *dbus,

                             BusConnection *orig_connection,

                             const gchar   *name,

                             const gchar   *old_name,

                             const gchar   *new_name,

                             BusIBusImpl   *ibus)

{

    PanelType panel_type = PANEL_TYPE_NONE;

    g_assert (BUS_IS_DBUS_IMPL (dbus));

    g_assert (name != NULL);

    g_assert (old_name != NULL);

    g_assert (new_name != NULL);

    g_assert (BUS_IS_IBUS_IMPL (ibus));

    if (!g_strcmp0 (name, IBUS_SERVICE_PANEL))

        panel_type = PANEL_TYPE_PANEL;

    else if (!g_strcmp0 (name, IBUS_SERVICE_PANEL_EXTENSION_EMOJI))

        panel_type = PANEL_TYPE_EXTENSION_EMOJI;

    if (panel_type != PANEL_TYPE_NONE) {

        if (g_strcmp0 (new_name, "") != 0) {

            /* a Panel process is started. */

            BusConnection *connection;

            BusInputContext *context = NULL;

            BusPanelProxy   **panel = (panel_type == PANEL_TYPE_PANEL) ?

                                      &ibus->panel : &ibus->emoji_extension;

            if (*panel != NULL) {

                ibus_proxy_destroy ((IBusProxy *)(*panel));

                /* panel should be NULL after destroy. See _panel_destroy_cb

                 * for details. */

                g_assert (*panel == NULL);

            }

            connection = bus_dbus_impl_get_connection_by_name (BUS_DEFAULT_DBUS, new_name);

            g_return_if_fail (connection != NULL);

            *panel = bus_panel_proxy_new (connection, panel_type);

            if (panel_type == PANEL_TYPE_EXTENSION_EMOJI)

                ibus->enable_emoji_extension = FALSE;

            g_signal_connect (*panel,

                              "destroy",

                              G_CALLBACK (_panel_destroy_cb),

                              ibus);

            g_signal_connect (*panel,

                              "panel-extension",

                              G_CALLBACK (_panel_panel_extension_cb),

                              ibus);

            g_signal_connect (*panel,

                              "panel-extension-register-keys",

                              G_CALLBACK (

                                      _panel_panel_extension_register_keys_cb),

                              ibus);

            g_signal_connect (

                    *panel,

                    "update-preedit-text-received",

                    G_CALLBACK (_panel_update_preedit_text_received_cb),

                    ibus);

            g_signal_connect (

                    *panel,

                    "update-lookup-table-received",

                    G_CALLBACK (_panel_update_lookup_table_received_cb),

                    ibus);

            g_signal_connect (

                    *panel,

                    "update-auxiliary-text-received",

                    G_CALLBACK (_panel_update_auxiliary_text_received_cb),

                    ibus);

            if (ibus->focused_context != NULL) {

                context = ibus->focused_context;

            }

            else if (ibus->use_global_engine) {

                context = ibus->fake_context;

            }

            if (context != NULL) {

                BusEngineProxy *engine;

                bus_panel_proxy_focus_in (*panel, context);

                engine = bus_input_context_get_engine (context);

                if (engine != NULL) {

                    IBusPropList *prop_list =

                        bus_engine_proxy_get_properties (engine);

                    bus_panel_proxy_register_properties (*panel, prop_list);

                }

            }

        }

    }

    bus_ibus_impl_component_name_owner_changed (ibus, name, old_name, new_name);

}

/**

 * bus_ibus_impl_init:

 *

 * The constructor of BusIBusImpl. Initialize all member variables of a BusIBusImpl object.

 */

static void

bus_ibus_impl_init (BusIBusImpl *ibus)

{

    ibus->factory_dict = g_hash_table_new_full (

                            g_str_hash,

                            g_str_equal,

                            NULL,

                            (GDestroyNotify) g_object_unref);

    ibus->fake_context = bus_input_context_new (NULL, "fake");

    g_object_ref_sink (ibus->fake_context);

    bus_dbus_impl_register_object (BUS_DEFAULT_DBUS,

                                   (IBusService *) ibus->fake_context);

    bus_input_context_set_capabilities (ibus->fake_context,

                                        IBUS_CAP_PREEDIT_TEXT |

                                        IBUS_CAP_FOCUS |

                                        IBUS_CAP_SURROUNDING_TEXT);

    g_signal_connect (ibus->fake_context,

                      "engine-changed",

                      G_CALLBACK (_context_engine_changed_cb),

                      ibus);

    bus_input_context_focus_in (ibus->fake_context);

    ibus->register_engine_list = NULL;

    ibus->contexts = NULL;

    ibus->focused_context = NULL;

    ibus->panel = NULL;

    ibus->emoji_extension = NULL;

    ibus->keymap = ibus_keymap_get ("us");

    ibus->use_sys_layout = TRUE;

    ibus->embed_preedit_text = TRUE;

    ibus->use_global_engine = TRUE;

    ibus->global_engine_name = NULL;

    ibus->global_previous_engine_name = NULL;

    /* focus the fake_context, if use_global_engine is enabled. */

    if (ibus->use_global_engine)

        bus_ibus_impl_set_focused_context (ibus, ibus->fake_context);

    g_signal_connect (BUS_DEFAULT_DBUS,

                      "name-owner-changed",

                      G_CALLBACK (_dbus_name_owner_changed_cb),

                      ibus);

    bus_ibus_impl_registry_init (ibus);

}

/**

 * bus_ibus_impl_destroy:

 *

 * The destructor of BusIBusImpl.

 */

static void

bus_ibus_impl_destroy (BusIBusImpl *ibus)

{

    pid_t pid;

    glong timeout;

    gint status;

    gboolean flag;

    g_list_foreach (ibus->components, (GFunc) bus_component_stop, NULL);

    pid = 0;

    timeout = 0;

    flag = FALSE;

    while (1) {

        while ((pid = waitpid (0, &status, WNOHANG)) > 0);

        if (pid == -1) { /* all children finished */

            break;

        }

        if (pid == 0) { /* no child status changed */

            g_usleep (1000);

            timeout += 1000;

            if (timeout >= G_USEC_PER_SEC) {

                if (flag == FALSE) {

                    gpointer old;

                    old = signal (SIGTERM, SIG_IGN);

                    /* send TERM signal to the whole process group (i.e. engines, panel, and config daemon.) */

                    kill (-getpid (), SIGTERM);

                    signal (SIGTERM, old);

                    flag = TRUE;

                }

                else {

                    g_warning ("Not every child processes exited!");

                    break;

                }

            }

        }

    }

    g_list_free_full (ibus->register_engine_list, g_object_unref);

    ibus->register_engine_list = NULL;

    if (ibus->factory_dict != NULL) {

        g_hash_table_destroy (ibus->factory_dict);

        ibus->factory_dict = NULL;

    }

    if (ibus->keymap != NULL) {

        g_object_unref (ibus->keymap);

        ibus->keymap = NULL;

    }

    g_free (ibus->global_engine_name);

    ibus->global_engine_name = NULL;

    g_free (ibus->global_previous_engine_name);

    ibus->global_previous_engine_name = NULL;

    if (ibus->fake_context) {

        g_object_unref (ibus->fake_context);

        ibus->fake_context = NULL;

    }

    bus_ibus_impl_registry_destroy (ibus);

    IBUS_OBJECT_CLASS (bus_ibus_impl_parent_class)->destroy (IBUS_OBJECT (ibus));

}

/**

 * _ibus_get_address:

 *

 * Implement the "Address" method call of the org.freedesktop.IBus interface.

 */

static GVariant *

_ibus_get_address (BusIBusImpl     *ibus,

                   GDBusConnection *connection,

                   GError         **error)

{

    if (error) {

        *error = NULL;

    }

    return g_variant_new_string (bus_server_get_address ());

}

static void

_ibus_get_address_depre (BusIBusImpl           *ibus,

                         GVariant              *parameters,

                         GDBusMethodInvocation *invocation)

{

    GDBusConnection *connection =

            g_dbus_method_invocation_get_connection (invocation);

    GError *error = NULL;

    GVariant *variant = NULL;

    g_warning ("org.freedesktop.IBus.GetAddress() is deprecated!");

    variant = _ibus_get_address (ibus, connection, &error);

    g_dbus_method_invocation_return_value (invocation,

            g_variant_new ("(s)", g_variant_get_string (variant, NULL)));

    g_variant_unref (variant);

}

static IBusEngineDesc *

_find_engine_desc_by_name (BusIBusImpl *ibus,

                           const gchar *engine_name)

{

    IBusEngineDesc *desc = NULL;

    GList *p;

    /* find engine in registered engine list */

    for (p = ibus->register_engine_list; p != NULL; p = p->next) {

        desc = (IBusEngineDesc *) p->data;

        if (g_strcmp0 (ibus_engine_desc_get_name (desc), engine_name) == 0)

            return desc;

    }

    return NULL;

}

/**

 * _context_request_engine_cb:

 *

 * A callback function to be called when the "request-engine" signal is sent to the context.

 */

static IBusEngineDesc *

_context_request_engine_cb (BusInputContext *context,

                            const gchar     *engine_name,

                            BusIBusImpl     *ibus)

{

    if (engine_name == NULL || engine_name[0] == '\0')

        engine_name = DEFAULT_ENGINE;

    return bus_ibus_impl_get_engine_desc (ibus, engine_name);

}

/**

 * bus_ibus_impl_get_engine_desc:

 *

 * Get the IBusEngineDesc by engine_name. If the engine_name is NULL, return

 * a default engine desc.

 */

static IBusEngineDesc *

bus_ibus_impl_get_engine_desc (BusIBusImpl *ibus,

                               const gchar *engine_name)

{

    g_return_val_if_fail (engine_name != NULL, NULL);

    g_return_val_if_fail (engine_name[0] != '\0', NULL);

    IBusEngineDesc *desc = _find_engine_desc_by_name (ibus, engine_name);

    if (desc == NULL) {

        desc = (IBusEngineDesc *) g_hash_table_lookup (ibus->engine_table,

                                                       engine_name);

    }

    return desc;

}

static void

bus_ibus_impl_set_context_engine_from_desc (BusIBusImpl     *ibus,

                                            BusInputContext *context,

                                            IBusEngineDesc  *desc)

{

    bus_input_context_set_engine_by_desc (context,

                                          desc,

                                          g_gdbus_timeout, /* timeout in msec. */

                                          NULL, /* we do not cancel the call. */

                                          NULL, /* use the default callback function. */

                                          NULL);

}

static void

_context_panel_extension_cb (BusInputContext    *context,

                             IBusExtensionEvent *event,

                             BusIBusImpl        *ibus)

{

    bus_ibus_impl_set_panel_extension_mode (ibus, event);

}

const static struct {

    const gchar *name;

    GCallback    callback;

} context_signals [] = {

    { "panel-extension",             G_CALLBACK (_context_panel_extension_cb) }

};

/**

 * bus_ibus_impl_set_focused_context:

 *

 * Set the current focused context.

 */

static void

bus_ibus_impl_set_focused_context (BusIBusImpl     *ibus,

                                   BusInputContext *context)

{

    gint i;

    BusEngineProxy *engine = NULL;

    guint purpose = 0;

    guint hints = 0;

    g_assert (BUS_IS_IBUS_IMPL (ibus));

    g_assert (context == NULL || BUS_IS_INPUT_CONTEXT (context));

    g_assert (context == NULL || bus_input_context_get_capabilities (context) & IBUS_CAP_FOCUS);

    /* Do noting if it is focused context. */

    if (ibus->focused_context == context) {

        return;

    }

    if (ibus->focused_context) {

        if (ibus->use_global_engine) {

            /* dettach engine from the focused context */

            engine = bus_input_context_get_engine (ibus->focused_context);

            if (engine) {

                g_object_ref (engine);

                bus_input_context_set_engine (ibus->focused_context, NULL);

                bus_input_context_set_emoji_extension (ibus->focused_context,

                                                       NULL);

            }

        }

        if (ibus->panel != NULL)

            bus_panel_proxy_focus_out (ibus->panel, ibus->focused_context);

        if (ibus->emoji_extension != NULL) {

            bus_panel_proxy_focus_out (ibus->emoji_extension,

                                       ibus->focused_context);

        }

        bus_input_context_set_emoji_extension (ibus->focused_context, NULL);

        bus_input_context_get_content_type (ibus->focused_context,

                                            &purpose, &hints);

        for (i = 0; i < G_N_ELEMENTS(context_signals); i++) {

            g_signal_handlers_disconnect_by_func (ibus->focused_context,

                    context_signals[i].callback, ibus);

        }

        g_object_unref (ibus->focused_context);

        ibus->focused_context = NULL;

    }

    if (context == NULL && ibus->use_global_engine) {

        context = ibus->fake_context;

        if (context)

            bus_input_context_set_content_type (context, purpose, hints);

    }

    if (context) {

        ibus->focused_context = (BusInputContext *) g_object_ref (context);

        /* attach engine to the focused context */

        if (engine != NULL) {

            bus_input_context_set_engine (context, engine);

            bus_input_context_enable (context);

            if (ibus->enable_emoji_extension) {

                bus_input_context_set_emoji_extension (context,

                                                       ibus->emoji_extension);

            } else {

                bus_input_context_set_emoji_extension (context, NULL);

            }

        }

        for (i = 0; i < G_N_ELEMENTS(context_signals); i++) {

            g_signal_connect (ibus->focused_context,

                              context_signals[i].name,

                              context_signals[i].callback,

                              ibus);

        }

        if (ibus->panel != NULL)

            bus_panel_proxy_focus_in (ibus->panel, context);

        if (ibus->emoji_extension != NULL)

            bus_panel_proxy_focus_in (ibus->emoji_extension, context);

    }

    if (engine != NULL)

        g_object_unref (engine);

}

static void

bus_ibus_impl_set_global_engine (BusIBusImpl    *ibus,

                                 BusEngineProxy *engine)