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

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

/* bus - The Input Bus

 * Copyright (C) 2010 Peng Huang <shawn.p.huang@gmail.com>

 * Copyright (C) 2010 Google 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 "component.h"

#include <gio/gio.h>

#include <glib/gstdio.h>

#include <stdlib.h>

#include <string.h>

#include "global.h"

#include "marshalers.h"

#include "types.h"

enum {

    LAST_SIGNAL,

};

enum {

    PROP_0 = 0,

    PROP_COMPONENT,

    PROP_FACTORY,

};

struct _BusComponent {

    IBusObject parent;

    /* instance members */

    /* an object which represents one XML file in the ibus/component/ directory. */

    IBusComponent *component;

    /* a proxy object which starts an engine. */

    BusFactoryProxy *factory;

    /* TRUE if the component started in the verbose mode. */

    gboolean verbose;

    /* TRUE if the component needs to be restarted when it dies. */

    gboolean restart;

    /* TRUE if the component will be destroyed with factory. */

    gboolean destroy_with_factory;

    /* process id of the process (e.g. ibus-config, ibus-engine-*, ..) of the component. */

    GPid     pid;

    guint    child_source_id;

};

struct _BusComponentClass {

    IBusObjectClass parent;

    /* class members */

};

/* functions prototype */

static GObject* bus_component_constructor   (GType                  type,

                                             guint                  n_construct_params,

                                             GObjectConstructParam *construct_params);

static void     bus_component_set_property  (BusComponent          *component,

                                             guint                  prop_id,

                                             const GValue          *value,

                                             GParamSpec            *pspec);

static void     bus_component_get_property  (BusComponent          *component,

                                             guint                  prop_id,

                                             GValue                *value,

                                             GParamSpec            *pspec);

static void     bus_component_destroy       (BusComponent          *component);

G_DEFINE_TYPE (BusComponent, bus_component, IBUS_TYPE_OBJECT)

static void

bus_component_class_init (BusComponentClass *class)

{

    GObjectClass *gobject_class = G_OBJECT_CLASS (class);

    IBusObjectClass *ibus_object_class = IBUS_OBJECT_CLASS (class);

    gobject_class->constructor  = bus_component_constructor;

    gobject_class->set_property = (GObjectSetPropertyFunc) bus_component_set_property;

    gobject_class->get_property = (GObjectGetPropertyFunc) bus_component_get_property;

    ibus_object_class->destroy  = (IBusObjectDestroyFunc) bus_component_destroy;

    /* install properties */

    g_object_class_install_property (gobject_class,

                    PROP_COMPONENT,

                    g_param_spec_object ("component", /* canonical name of the property */

                        "component", /* nick name */

                        "component", /* description */

                        IBUS_TYPE_COMPONENT, /* object type */

                        G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));

    g_object_class_install_property (gobject_class,

                    PROP_FACTORY,

                    g_param_spec_object ("factory",

                        "factory",

                        "factory",

                        BUS_TYPE_FACTORY_PROXY,

                        G_PARAM_READWRITE));

}

static void

bus_component_init (BusComponent *component)

{

}

/**

 * bus_component_constructor:

 *

 * A constructor method which is called after bus_component_init is called.

 */

static GObject*

bus_component_constructor (GType                  type,

                           guint                  n_construct_params,

                           GObjectConstructParam *construct_params)

{

    GObject *object;

    object = G_OBJECT_CLASS (bus_component_parent_class)->constructor (type,

                                                                       n_construct_params,

                                                                       construct_params);

    BusComponent *component = (BusComponent *) object;

    /* we have to override the _constructor method since in _init method, the component->component property is not set yet. */

    g_assert (IBUS_IS_COMPONENT (component->component));

    static GQuark quark = 0;

    if (quark == 0) {

        quark = g_quark_from_static_string ("BusComponent");

    }

    /* associate each engine with BusComponent. a component might have one or more components. For example, ibus-engine-pinyin would

     * have two - 'pinyin' and 'bopomofo' and ibus-engine-m17n has many. On the other hand, the gtkpanel component does not have an

     * engine, of course. */

    GList *engines = ibus_component_get_engines (component->component);

    GList *p;

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

        g_object_set_qdata ((GObject *) p->data, quark, component);

    }

    g_list_free (engines);

    return object;

}

static void

bus_component_set_property (BusComponent *component,

                            guint         prop_id,

                            const GValue *value,

                            GParamSpec   *pspec)

{

    switch (prop_id) {

    case PROP_COMPONENT:

        g_assert (component->component == NULL);

        component->component = g_value_dup_object (value);

        break;

    case PROP_FACTORY:

        bus_component_set_factory (component, (BusFactoryProxy *) g_value_get_object (value));

        break;

    default:

        G_OBJECT_WARN_INVALID_PROPERTY_ID (component, prop_id, pspec);

    }

}

static void

bus_component_get_property (BusComponent *component,

                            guint         prop_id,

                            GValue       *value,

                            GParamSpec   *pspec)

{

    switch (prop_id) {

    case PROP_COMPONENT:

        g_value_set_object (value, bus_component_get_component (component));

        break;

    case PROP_FACTORY:

        g_value_set_object (value, bus_component_get_factory (component));

        break;

    default:

        G_OBJECT_WARN_INVALID_PROPERTY_ID (component, prop_id, pspec);

    }

}

static void

bus_component_destroy (BusComponent *component)

{

    if (component->pid != 0) {

        bus_component_stop (component);

        g_spawn_close_pid (component->pid);

        component->pid = 0;

    }

    if (component->child_source_id != 0) {

        g_source_remove (component->child_source_id);

        component->child_source_id = 0;

    }

    if (component->component != NULL) {

        g_object_unref (component->component);

        component->component = NULL;

    }

    IBUS_OBJECT_CLASS (bus_component_parent_class)->destroy (IBUS_OBJECT (component));

}

BusComponent *

bus_component_new (IBusComponent   *component,

                   BusFactoryProxy *factory)

{

    g_assert (IBUS_IS_COMPONENT (component));

    return (BusComponent *) g_object_new (BUS_TYPE_COMPONENT,

                                          /* properties below will be set via the bus_component_set_property function. */

                                          "component", component,

                                          "factory", factory,

                                          NULL);

}

static void

bus_component_factory_destroy_cb (BusFactoryProxy *factory,

                                  BusComponent    *component)

{

    g_return_if_fail (component->factory == factory);

    g_object_unref (component->factory);

    component->factory = NULL;

    /* emit the "notify" signal for the factory property on component. */

    g_object_notify ((GObject *) component, "factory");

    if (component->destroy_with_factory)

        ibus_object_destroy ((IBusObject *) component);

}

IBusComponent *

bus_component_get_component (BusComponent *component)

{

    g_assert (BUS_IS_COMPONENT (component));

    return component->component;

}

void

bus_component_set_factory (BusComponent    *component,

                           BusFactoryProxy *factory)

{

    g_assert (BUS_IS_COMPONENT (component));

    if (component->factory == factory) {

        return;

    }

    if (component->factory) {

        g_signal_handlers_disconnect_by_func (component->factory,

                                              bus_component_factory_destroy_cb,

                                              component);

        g_object_unref (component->factory);

        component->factory = NULL;

    }

    if (factory) {

        g_assert (BUS_IS_FACTORY_PROXY (factory));

        component->factory = (BusFactoryProxy *) g_object_ref (factory);

        g_signal_connect (factory, "destroy",

                          G_CALLBACK (bus_component_factory_destroy_cb), component);

    }

    /* emit the "notify" signal for the factory property on component. */

    g_object_notify ((GObject*) component, "factory");

}

BusFactoryProxy *

bus_component_get_factory (BusComponent *component)

{

    g_assert (BUS_IS_COMPONENT (component));

    return component->factory;

}

const gchar *

bus_component_get_name (BusComponent *component)

{

    g_assert (BUS_IS_COMPONENT (component));

    return ibus_component_get_name (component->component);

}

GList *

bus_component_get_engines (BusComponent *component)

{

    g_assert (BUS_IS_COMPONENT (component));

    return ibus_component_get_engines (component->component);

}

void

bus_component_set_destroy_with_factory (BusComponent *component,

                                        gboolean      with_factory)

{

    g_assert (BUS_IS_COMPONENT (component));

    component->destroy_with_factory = with_factory;

}

void

bus_component_set_restart (BusComponent *component,

                           gboolean      restart)

{

    g_assert (BUS_IS_COMPONENT (component));

    component->restart = restart;

}

/**

 * bus_component_child_cb:

 *

 * A callback function to be called when the child process is terminated.

 */

static void

bus_component_child_cb (GPid          pid,

                        gint          status,

                        BusComponent *component)

{

    g_assert (BUS_IS_COMPONENT (component));

    g_assert (component->pid == pid);

    g_spawn_close_pid (pid);

    component->pid = 0;

    component->child_source_id = 0;

    if (component->restart) {

        bus_component_start (component, component->verbose);

    }

}

gboolean

bus_component_start (BusComponent *component,

                     gboolean      verbose)

{

    g_assert (BUS_IS_COMPONENT (component));

    if (component->pid != 0)

        return TRUE;

    component->verbose = verbose;

    gint argc;

    gchar **argv;

    gboolean retval;

    GError *error = NULL;

    if (!g_shell_parse_argv (ibus_component_get_exec (component->component),

                             &argc,

                             &argv,

                             &error)) {

        g_warning ("Can not parse component %s exec: %s",

                   ibus_component_get_name (component->component),

                   error->message);

        g_error_free (error);

        return FALSE;

    }

    error = NULL;

    GSpawnFlags flags = G_SPAWN_DO_NOT_REAP_CHILD;

    if (!verbose) {

        flags |= G_SPAWN_STDOUT_TO_DEV_NULL | G_SPAWN_STDERR_TO_DEV_NULL;

    }

    retval = g_spawn_async (NULL, argv, NULL,

                            flags,

                            NULL, NULL,

                            &(component->pid), &error);

    g_strfreev (argv);

    if (!retval) {

        g_warning ("Can not execute component %s: %s",

                   ibus_component_get_name (component->component),

                   error->message);

        g_error_free (error);

        return FALSE;

    }

    component->child_source_id =

        g_child_watch_add (component->pid,

                           (GChildWatchFunc) bus_component_child_cb,

                           component);

    return TRUE;

}

gboolean

bus_component_stop (BusComponent *component)

{

    g_assert (BUS_IS_COMPONENT (component));

    if (component->pid == 0)

        return TRUE;

    kill (component->pid, SIGTERM);

    return TRUE;

}

gboolean

bus_component_is_running (BusComponent *component)

{

    g_assert (BUS_IS_COMPONENT (component));

    return (component->pid != 0);

}

BusComponent *

bus_component_from_engine_desc (IBusEngineDesc *engine)

{

    g_assert (IBUS_IS_ENGINE_DESC (engine));

    static GQuark quark = 0;

    if (quark == 0) {

        quark = g_quark_from_static_string ("BusComponent");

    }

    return (BusComponent *) g_object_get_qdata ((GObject *) engine, quark);

}