/*
 * * Copyright (C) 2008-2011 Ali <aliov@xfce.org>
 *
 * Licensed under the GNU General Public License Version 2
 *
 * 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 Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif

#include <glib.h>

#include <libxfce4util/libxfce4util.h>

#include "xfpm-inhibit.h"
#include "xfpm-dbus-monitor.h"
#include "xfpm-errors.h"
#include "xfpm-debug.h"

static void xfpm_inhibit_finalize   (GObject *object);

static void xfpm_inhibit_dbus_class_init  (XfpmInhibitClass *klass);
static void xfpm_inhibit_dbus_init	  (XfpmInhibit *inhibit);

struct XfpmInhibitPrivate
{
    XfpmDBusMonitor *monitor;
    GPtrArray       *array;
    gboolean         inhibited;
};

typedef struct
{
    gchar *app_name;
    gchar *unique_name;
    guint  cookie;

} Inhibitor;

enum
{
    HAS_INHIBIT_CHANGED,
    INHIBIT_LIST_CHANGED,
    LAST_SIGNAL
};

static guint signals[LAST_SIGNAL] = { 0 };

G_DEFINE_TYPE_WITH_PRIVATE (XfpmInhibit, xfpm_inhibit, G_TYPE_OBJECT)

static void
xfpm_inhibit_free_inhibitor (XfpmInhibit *inhibit, Inhibitor *inhibitor)
{
    g_return_if_fail (inhibitor != NULL );

    g_ptr_array_remove (inhibit->priv->array, inhibitor);

    g_free (inhibitor->app_name);
    g_free (inhibitor->unique_name);
    g_free (inhibitor);
}

static gboolean
xfpm_inhibit_has_inhibit_changed (XfpmInhibit *inhibit)
{
    if ( inhibit->priv->array->len == 0 && inhibit->priv->inhibited == TRUE )
    {
	XFPM_DEBUG("Inhibit removed");
	inhibit->priv->inhibited = FALSE;
	g_signal_emit (G_OBJECT(inhibit), signals[HAS_INHIBIT_CHANGED], 0, inhibit->priv->inhibited);
    }
    else if ( inhibit->priv->array->len != 0 && inhibit->priv->inhibited == FALSE )
    {
	XFPM_DEBUG("Inhibit added");
	inhibit->priv->inhibited = TRUE;
	g_signal_emit (G_OBJECT(inhibit), signals[HAS_INHIBIT_CHANGED], 0, inhibit->priv->inhibited);
    }

    /* Always emite the INHIBIT_LIST_CHANGED for any change so the panel plugin
     * stays in sync */
    g_signal_emit (G_OBJECT(inhibit), signals[INHIBIT_LIST_CHANGED], 0, inhibit->priv->inhibited);

    return inhibit->priv->inhibited;
}

static guint
xfpm_inhibit_get_cookie (XfpmInhibit *inhibit)
{
    guint max = 0;
    guint i;
    Inhibitor *inhibitor;

    for ( i = 0; i<inhibit->priv->array->len; i++)
    {
	inhibitor = g_ptr_array_index (inhibit->priv->array, i);
	max = MAX (max, inhibitor->cookie);
    }
    return (guint) g_random_int_range ( max + 1, max + 40);
}

static guint
xfpm_inhibit_add_application (XfpmInhibit *inhibit, const gchar *app_name, const gchar *unique_name)
{
    guint cookie;
    Inhibitor *inhibitor;

    inhibitor = g_new0 (Inhibitor, 1);

    cookie = xfpm_inhibit_get_cookie (inhibit);

    inhibitor->cookie      = cookie;
    inhibitor->app_name    = g_strdup (app_name);
    inhibitor->unique_name = g_strdup (unique_name);

    g_ptr_array_add (inhibit->priv->array, inhibitor);

    return cookie;
}

static Inhibitor *
xfpm_inhibit_find_application_by_cookie (XfpmInhibit *inhibit, guint cookie)
{
    guint i;
    Inhibitor *inhibitor;
    for ( i = 0; i < inhibit->priv->array->len; i++)
    {
	inhibitor = g_ptr_array_index (inhibit->priv->array, i);
	if ( inhibitor->cookie == cookie )
	{
	    return inhibitor;
	}
    }
    return NULL;
}

static Inhibitor *
xfpm_inhibit_find_application_by_unique_connection_name (XfpmInhibit *inhibit, const gchar *unique_name)
{
    guint i;
    Inhibitor *inhibitor;
    for ( i = 0; i < inhibit->priv->array->len; i++)
    {
	inhibitor = g_ptr_array_index (inhibit->priv->array, i);
	if ( g_strcmp0 (inhibitor->unique_name, unique_name ) == 0 )
	{
	    return inhibitor;
	}
    }
    return NULL;
}

static gboolean
xfpm_inhibit_remove_application_by_cookie (XfpmInhibit *inhibit, guint cookie)
{
    Inhibitor *inhibitor;

    inhibitor = xfpm_inhibit_find_application_by_cookie (inhibit, cookie);

    if ( inhibitor )
    {
	xfpm_dbus_monitor_remove_unique_name (inhibit->priv->monitor, G_BUS_TYPE_SESSION, inhibitor->unique_name);
	xfpm_inhibit_free_inhibitor (inhibit, inhibitor);
	return TRUE;
    }
    return FALSE;
}

static void
xfpm_inhibit_connection_lost_cb (XfpmDBusMonitor *monitor, gchar *unique_name,
				 gboolean on_session, XfpmInhibit *inhibit)
{
    Inhibitor *inhibitor;

    if ( !on_session)
	return;

    inhibitor = xfpm_inhibit_find_application_by_unique_connection_name (inhibit, unique_name );

    if ( inhibitor )
    {
	XFPM_DEBUG ("Application=%s with unique connection name=%s disconnected", inhibitor->app_name, inhibitor->unique_name);
	xfpm_inhibit_free_inhibitor (inhibit, inhibitor);
	xfpm_inhibit_has_inhibit_changed (inhibit);
    }
}

static void
xfpm_inhibit_class_init(XfpmInhibitClass *klass)
{
    GObjectClass *object_class = G_OBJECT_CLASS(klass);

    signals[HAS_INHIBIT_CHANGED] =
	    g_signal_new ("has-inhibit-changed",
			 XFPM_TYPE_INHIBIT,
			 G_SIGNAL_RUN_LAST,
			 G_STRUCT_OFFSET(XfpmInhibitClass, has_inhibit_changed),
			 NULL, NULL,
			 g_cclosure_marshal_VOID__BOOLEAN,
			 G_TYPE_NONE, 1, G_TYPE_BOOLEAN);

    signals[INHIBIT_LIST_CHANGED] =
	    g_signal_new ("inhibitors-list-changed",
			 XFPM_TYPE_INHIBIT,
			 G_SIGNAL_RUN_LAST,
			 G_STRUCT_OFFSET(XfpmInhibitClass, inhibitors_list_changed),
			 NULL, NULL,
			 g_cclosure_marshal_VOID__BOOLEAN,
			 G_TYPE_NONE, 1, G_TYPE_BOOLEAN);

    object_class->finalize = xfpm_inhibit_finalize;

    xfpm_inhibit_dbus_class_init (klass);
}

static void
xfpm_inhibit_init (XfpmInhibit *inhibit)
{
    inhibit->priv = xfpm_inhibit_get_instance_private (inhibit);

    inhibit->priv->array   = g_ptr_array_new ();
    inhibit->priv->monitor = xfpm_dbus_monitor_new ();

    g_signal_connect (inhibit->priv->monitor, "unique-name-lost",
		      G_CALLBACK (xfpm_inhibit_connection_lost_cb), inhibit);

    xfpm_inhibit_dbus_init (inhibit);
}

static void
xfpm_inhibit_finalize (GObject *object)
{
    XfpmInhibit *inhibit;
    Inhibitor *inhibitor;
    guint i;

    inhibit = XFPM_INHIBIT(object);

    g_object_unref (inhibit->priv->monitor);

    for ( i = 0; i<inhibit->priv->array->len; i++)
    {
	inhibitor = g_ptr_array_index (inhibit->priv->array, i);
	xfpm_inhibit_free_inhibitor (inhibit, inhibitor);
    }

    g_ptr_array_free (inhibit->priv->array, TRUE);

    G_OBJECT_CLASS(xfpm_inhibit_parent_class)->finalize(object);
}

XfpmInhibit *
xfpm_inhibit_new(void)
{
    static gpointer xfpm_inhibit_object = NULL;

    if ( G_LIKELY (xfpm_inhibit_object != NULL) )
    {
	g_object_ref (xfpm_inhibit_object);
    }
    else
    {
	xfpm_inhibit_object = g_object_new (XFPM_TYPE_INHIBIT, NULL);
	g_object_add_weak_pointer (xfpm_inhibit_object, &xfpm_inhibit_object);
    }
    return XFPM_INHIBIT (xfpm_inhibit_object);
}

/***
 * xfpm_inhibit_get_inhibit_list
 * @inhibit: the XfpmInhibit object.
 *
 * Returns: An array of applications that are currently inhibiting xfpm.
 *          Call g_free on the returned array when done using it.
 */
const gchar **
xfpm_inhibit_get_inhibit_list (XfpmInhibit *inhibit)
{
    guint i;
    Inhibitor *inhibitor;
    const gchar **OUT_inhibitors;

    XFPM_DEBUG ("entering xfpm_inhibit_get_inhibit_list");

    OUT_inhibitors = g_new (const gchar *, inhibit->priv->array->len + 1);

    for ( i = 0; i<inhibit->priv->array->len; i++)
    {
	inhibitor = g_ptr_array_index (inhibit->priv->array, i);
	OUT_inhibitors[i] = inhibitor->app_name;
    }

    OUT_inhibitors[inhibit->priv->array->len] = NULL;

    return OUT_inhibitors;
}

/*
 *
 * DBus server implementation for org.freedesktop.PowerManagement.Inhibit
 *
 */
static gboolean xfpm_inhibit_inhibit  	(XfpmInhibit *inhibit,
					 GDBusMethodInvocation *invocation,
					 const gchar *IN_appname,
					 const gchar *IN_reason,
					 gpointer user_data);

static gboolean xfpm_inhibit_un_inhibit (XfpmInhibit *inhibit,
					 GDBusMethodInvocation *invocation,
					 guint IN_cookie,
					 gpointer user_data);

static gboolean xfpm_inhibit_has_inhibit(XfpmInhibit *inhibit,
					 GDBusMethodInvocation *invocation,
					 gpointer user_data);

static gboolean xfpm_inhibit_get_inhibitors (XfpmInhibit *inhibit,
					     GDBusMethodInvocation *invocation,
					     gpointer user_data);

#include "org.freedesktop.PowerManagement.Inhibit.h"

static void xfpm_inhibit_dbus_class_init  (XfpmInhibitClass *klass)
{
}

static void xfpm_inhibit_dbus_init	  (XfpmInhibit *inhibit)
{
    GDBusConnection *bus = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, NULL);
    XfpmPowerManagementInhibit *inhibit_dbus;

    inhibit_dbus = xfpm_power_management_inhibit_skeleton_new ();
    g_dbus_interface_skeleton_export (G_DBUS_INTERFACE_SKELETON (inhibit_dbus),
                                      bus,
                                      "/org/freedesktop/PowerManagement/Inhibit",
                                      NULL);

    g_signal_connect_swapped (inhibit_dbus,
			      "handle-inhibit",
			      G_CALLBACK (xfpm_inhibit_inhibit),
			      inhibit);
    g_signal_connect_swapped (inhibit_dbus,
			      "handle-un-inhibit",
			      G_CALLBACK (xfpm_inhibit_un_inhibit),
			      inhibit);
    g_signal_connect_swapped (inhibit_dbus,
			      "handle-has-inhibit",
			      G_CALLBACK (xfpm_inhibit_has_inhibit),
			      inhibit);
    g_signal_connect_swapped (inhibit_dbus,
			      "handle-get-inhibitors",
			      G_CALLBACK (xfpm_inhibit_get_inhibitors),
			      inhibit);
}

static gboolean xfpm_inhibit_inhibit  	(XfpmInhibit *inhibit,
					 GDBusMethodInvocation *invocation,
					 const gchar *IN_appname,
					 const gchar *IN_reason,
					 gpointer user_data)
{
    const gchar *sender;
    guint cookie;

    if ( IN_appname == NULL || IN_reason == NULL )
    {
	g_dbus_method_invocation_return_error (invocation,
					       XFPM_ERROR,
					       XFPM_ERROR_INVALID_ARGUMENTS,
					       _("Invalid arguments"));

	return TRUE;
    }

    sender = g_dbus_method_invocation_get_sender (invocation);
    cookie = xfpm_inhibit_add_application (inhibit, IN_appname, sender);

    XFPM_DEBUG("Inhibit send application name=%s reason=%s sender=%s", IN_appname, IN_reason ,sender);

    xfpm_inhibit_has_inhibit_changed (inhibit);

    xfpm_dbus_monitor_add_unique_name (inhibit->priv->monitor, G_BUS_TYPE_SESSION, sender);

    xfpm_power_management_inhibit_complete_inhibit (user_data,
                                                    invocation,
                                                    cookie);

    return TRUE;
}

static gboolean xfpm_inhibit_un_inhibit    (XfpmInhibit *inhibit,
					    GDBusMethodInvocation *invocation,
					    guint IN_cookie,
					    gpointer user_data)
{
    XFPM_DEBUG("UnHibit message received");

    if (!xfpm_inhibit_remove_application_by_cookie (inhibit, IN_cookie))
    {
	g_dbus_method_invocation_return_error (invocation,
					       XFPM_ERROR,
					       XFPM_ERROR_COOKIE_NOT_FOUND,
					       _("Invalid cookie"));
	return TRUE;
    }

    xfpm_inhibit_has_inhibit_changed (inhibit);

    xfpm_power_management_inhibit_complete_un_inhibit (user_data, invocation);

    return TRUE;
}

static gboolean xfpm_inhibit_has_inhibit   (XfpmInhibit *inhibit,
					    GDBusMethodInvocation *invocation,
					    gpointer user_data)
{
    XFPM_DEBUG("Has Inhibit message received");

    xfpm_power_management_inhibit_complete_has_inhibit (user_data,
                                                        invocation,
                                                        inhibit->priv->inhibited);

    return TRUE;
}

static gboolean xfpm_inhibit_get_inhibitors (XfpmInhibit *inhibit,
					     GDBusMethodInvocation *invocation,
					     gpointer user_data)
{
    const gchar **OUT_inhibitors;

    XFPM_DEBUG ("Get Inhibitors message received");

    OUT_inhibitors = xfpm_inhibit_get_inhibit_list (inhibit);

    xfpm_power_management_inhibit_complete_get_inhibitors (user_data,
							   invocation,
							   OUT_inhibitors);

    g_free (OUT_inhibitors);

    return TRUE;
}
