/*
A library to take the object model made consistent by libdbusmenu-glib
and visualize it in GTK.

Copyright 2009 Canonical Ltd.

Authors:
    Ted Gould <ted@canonical.com>

This program is free software: you can redistribute it and/or modify it 
under the terms of either or both of the following licenses:

1) the GNU Lesser General Public License version 3, as published by the 
Free Software Foundation; and/or
2) the GNU Lesser General Public License version 2.1, as published by 
the Free Software Foundation.

This program is distributed in the hope that it will be useful, but 
WITHOUT ANY WARRANTY; without even the implied warranties of 
MERCHANTABILITY, SATISFACTORY QUALITY or FITNESS FOR A PARTICULAR 
PURPOSE.  See the applicable version of the GNU Lesser General Public 
License for more details.

You should have received a copy of both the GNU Lesser General Public 
License version 3 and version 2.1 along with this program.  If not, see 
<http://www.gnu.org/licenses/>
*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <gtk/gtk.h>

#include "menu.h"
#include "libdbusmenu-glib/client.h"
#include "client.h"

/* Properties */
enum {
	PROP_0,
	PROP_DBUSOBJECT,
	PROP_DBUSNAME
};

/* Private */
typedef struct _DbusmenuGtkMenuPrivate DbusmenuGtkMenuPrivate;
struct _DbusmenuGtkMenuPrivate {
	DbusmenuGtkClient * client;

	gchar * dbus_object;
	gchar * dbus_name;
};

#define DBUSMENU_GTKMENU_GET_PRIVATE(o) \
(G_TYPE_INSTANCE_GET_PRIVATE ((o), DBUSMENU_GTKMENU_TYPE, DbusmenuGtkMenuPrivate))

/* Prototypes */
static void dbusmenu_gtkmenu_class_init (DbusmenuGtkMenuClass *klass);
static void dbusmenu_gtkmenu_init       (DbusmenuGtkMenu *self);
static void dbusmenu_gtkmenu_dispose    (GObject *object);
static void dbusmenu_gtkmenu_finalize   (GObject *object);
static void set_property (GObject * obj, guint id, const GValue * value, GParamSpec * pspec);
static void get_property (GObject * obj, guint id, GValue * value, GParamSpec * pspec);
/* Internal */
static void build_client (DbusmenuGtkMenu * self);
static void child_realized (DbusmenuMenuitem * child, gpointer userdata);

/* GObject Stuff */
G_DEFINE_TYPE (DbusmenuGtkMenu, dbusmenu_gtkmenu, GTK_TYPE_MENU);

static void
dbusmenu_gtkmenu_class_init (DbusmenuGtkMenuClass *klass)
{
	GObjectClass *object_class = G_OBJECT_CLASS (klass);

	g_type_class_add_private (klass, sizeof (DbusmenuGtkMenuPrivate));

	object_class->dispose = dbusmenu_gtkmenu_dispose;
	object_class->finalize = dbusmenu_gtkmenu_finalize;
	object_class->set_property = set_property;
	object_class->get_property = get_property;

	g_object_class_install_property (object_class, PROP_DBUSOBJECT,
	                                 g_param_spec_string(DBUSMENU_CLIENT_PROP_DBUS_OBJECT, "DBus Object we represent",
	                                              "The Object on the client that we're getting our data from.",
	                                              NULL,
	                                              G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));
	g_object_class_install_property (object_class, PROP_DBUSNAME,
	                                 g_param_spec_string(DBUSMENU_CLIENT_PROP_DBUS_NAME, "DBus Client we connect to",
	                                              "Name of the DBus client we're connecting to.",
	                                              NULL,
	                                              G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));

	return;
}

static void
menu_focus_cb(DbusmenuGtkMenu * menu, gpointer userdata)
{
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(menu);
	if (priv->client != NULL) {
		/* TODO: We should stop the display of the menu
		         until the about to show call returns. */
		dbusmenu_client_send_about_to_show(DBUSMENU_CLIENT(priv->client), 0, NULL, NULL);
	}
	return;
}

static void
dbusmenu_gtkmenu_init (DbusmenuGtkMenu *self)
{
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(self);

	priv->client = NULL;

	priv->dbus_object = NULL;
	priv->dbus_name = NULL;

	g_signal_connect(G_OBJECT(self), "focus", G_CALLBACK(menu_focus_cb), self);

	return;
}

static void
dbusmenu_gtkmenu_dispose (GObject *object)
{
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(object);

	if (priv->client != NULL) {
		g_object_unref(G_OBJECT(priv->client));
		priv->client = NULL;
	}

	G_OBJECT_CLASS (dbusmenu_gtkmenu_parent_class)->dispose (object);
	return;
}

static void
dbusmenu_gtkmenu_finalize (GObject *object)
{
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(object);

	g_free(priv->dbus_object);
	priv->dbus_object = NULL;

	g_free(priv->dbus_name);
	priv->dbus_name = NULL;

	G_OBJECT_CLASS (dbusmenu_gtkmenu_parent_class)->finalize (object);
	return;
}

static void
set_property (GObject * obj, guint id, const GValue * value, GParamSpec * pspec)
{
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(obj);

	switch (id) {
	case PROP_DBUSNAME:
		priv->dbus_name = g_value_dup_string(value);
		if (priv->dbus_name != NULL && priv->dbus_object != NULL) {
			build_client(DBUSMENU_GTKMENU(obj));
		}
		break;
	case PROP_DBUSOBJECT:
		priv->dbus_object = g_value_dup_string(value);
		if (priv->dbus_name != NULL && priv->dbus_object != NULL) {
			build_client(DBUSMENU_GTKMENU(obj));
		}
		break;
	default:
		g_warning("Unknown property %d.", id);
		return;
	}

	return;
}

static void
get_property (GObject * obj, guint id, GValue * value, GParamSpec * pspec)
{
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(obj);

	switch (id) {
	case PROP_DBUSNAME:
		g_value_set_string(value, priv->dbus_name);
		break;
	case PROP_DBUSOBJECT:
		g_value_set_string(value, priv->dbus_object);
		break;
	default:
		g_warning("Unknown property %d.", id);
		return;
	}

	return;
}

/* Internal Functions */

#ifdef MASSIVEDEBUGGING
typedef struct {
	GtkMenuItem * mi;
	gint finalpos;
	gboolean found;
} menu_pos_t;

static void
find_pos (GtkWidget * widget, gpointer data)
{
	menu_pos_t * menu_pos = (menu_pos_t *)data;
	if (menu_pos->found) return;
	if ((gpointer)(menu_pos->mi) == (gpointer)widget) {
		menu_pos->found = TRUE;
	} else {
		menu_pos->finalpos++;
	}
	return;
}
#endif


/* Called when a new child of the root item is
   added.  Sets up a signal for when it's actually
   realized. */
static void
root_child_added (DbusmenuMenuitem * root, DbusmenuMenuitem * child, guint position, DbusmenuGtkMenu * menu)
{
	#ifdef MASSIVEDEBUGGING
	g_debug("Root new child");
	#endif
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(menu);

	g_signal_connect(G_OBJECT(child), DBUSMENU_MENUITEM_SIGNAL_REALIZED, G_CALLBACK(child_realized), menu);

	GtkMenuItem * mi = dbusmenu_gtkclient_menuitem_get(priv->client, child);
	if (mi != NULL) {
		GtkWidget * item = GTK_WIDGET(mi);
		gtk_menu_insert(GTK_MENU(menu), item, dbusmenu_menuitem_get_position_realized(child, root));
		#ifdef MASSIVEDEBUGGING
		menu_pos_t menu_pos;
		menu_pos.mi = mi;
		menu_pos.finalpos = 0;
		menu_pos.found = FALSE;

		gtk_container_foreach(GTK_CONTAINER(menu), find_pos, &menu_pos);
		g_debug("Menu position requested was %d but got %d", position, menu_pos.finalpos);
		#endif
	}
	return;
}

/* When one of the children move we need to react to that and
   move it on the GTK side as well. */
static void
root_child_moved (DbusmenuMenuitem * root, DbusmenuMenuitem * child, guint newposition, guint oldposition, DbusmenuGtkMenu * menu)
{
	#ifdef MASSIVEDEBUGGING
	g_debug("Root child moved");
	#endif
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(menu);
	gtk_menu_reorder_child(GTK_MENU(menu), GTK_WIDGET(dbusmenu_gtkclient_menuitem_get(priv->client, child)), dbusmenu_menuitem_get_position_realized(child, root));
	return;
}

/* When a root child item disappears. */
static void
root_child_delete (DbusmenuMenuitem * root, DbusmenuMenuitem * child, DbusmenuGtkMenu * menu)
{
	#ifdef MASSIVEDEBUGGING
	g_debug("Root child deleted");
	#endif
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(menu);
	GtkWidget * item = GTK_WIDGET(dbusmenu_gtkclient_menuitem_get(priv->client, child));
	if (item != NULL) {
		gtk_container_remove(GTK_CONTAINER(menu), item);
	}

	if (g_list_length(dbusmenu_menuitem_get_children(root)) == 0) {
		gtk_widget_hide(GTK_WIDGET(menu));
	}
	return;
}

/* Called when the child is realized, and thus has all of it's
   properties and GTK-isms.  We can put it in our menu here. */
static void
child_realized (DbusmenuMenuitem * child, gpointer userdata)
{
	#ifdef MASSIVEDEBUGGING
	g_debug("Root child realized");
	#endif
	g_return_if_fail(DBUSMENU_IS_GTKMENU(userdata));

	DbusmenuGtkMenu * menu = DBUSMENU_GTKMENU(userdata);
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(menu);

	GtkWidget * child_widget = GTK_WIDGET(dbusmenu_gtkclient_menuitem_get(priv->client, child));

	if (child_widget != NULL) {
		gtk_menu_append(menu, child_widget);
		gtk_menu_reorder_child(GTK_MENU(menu), child_widget, dbusmenu_menuitem_get_position_realized(child, dbusmenu_client_get_root(DBUSMENU_CLIENT(priv->client))));
	} else {
		g_warning("Child is realized, but doesn't have a GTK Widget!");
	}

	return;
}

/* When the root menuitem changes we need to resetup things so that
   we're back in the game. */
static void
root_changed (DbusmenuGtkClient * client, DbusmenuMenuitem * newroot, DbusmenuGtkMenu * menu) {
	if (newroot == NULL) {
		gtk_widget_hide(GTK_WIDGET(menu));
		return;
	}

	g_signal_connect(G_OBJECT(newroot), DBUSMENU_MENUITEM_SIGNAL_CHILD_ADDED,   G_CALLBACK(root_child_added),  menu);
	g_signal_connect(G_OBJECT(newroot), DBUSMENU_MENUITEM_SIGNAL_CHILD_MOVED,   G_CALLBACK(root_child_moved),  menu);
	g_signal_connect(G_OBJECT(newroot), DBUSMENU_MENUITEM_SIGNAL_CHILD_REMOVED, G_CALLBACK(root_child_delete), menu);

	GList * child = NULL;
	guint count = 0;
	for (child = dbusmenu_menuitem_get_children(newroot); child != NULL; child = g_list_next(child)) {
		/* gtk_menu_append(menu, GTK_WIDGET(dbusmenu_gtkclient_menuitem_get(client, child->data))); */
		g_signal_connect(G_OBJECT(child->data), DBUSMENU_MENUITEM_SIGNAL_REALIZED, G_CALLBACK(child_realized), menu);
		count++;
	}

	if (count > 0) {
		gtk_widget_show(GTK_WIDGET(menu));
	} else {
		gtk_widget_hide(GTK_WIDGET(menu));
	}

	return;
}

/* Builds the client and connects all of the signals
   up for it so that it's happy-happy */
static void
build_client (DbusmenuGtkMenu * self)
{
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(self);

	if (priv->client == NULL) {
		priv->client = dbusmenu_gtkclient_new(priv->dbus_name, priv->dbus_object);

		/* Register for layout changes, this should come after the
		   creation of the client pulls it from DBus */
		g_signal_connect(G_OBJECT(priv->client), DBUSMENU_GTKCLIENT_SIGNAL_ROOT_CHANGED, G_CALLBACK(root_changed), self);
	}

	return;
}

/* Public API */

/**
	dbusmenu_gtkmenu_new:
	@dbus_name: Name of the #DbusmenuServer on DBus
	@dbus_name: Name of the object on the #DbusmenuServer

	Creates a new #DbusmenuGtkMenu object and creates a #DbusmenuClient
	that connects across DBus to a #DbusmenuServer.

	Return value: A new #DbusmenuGtkMenu sync'd with a server
*/
DbusmenuGtkMenu *
dbusmenu_gtkmenu_new (gchar * dbus_name, gchar * dbus_object)
{
	return g_object_new(DBUSMENU_GTKMENU_TYPE,
	                    DBUSMENU_CLIENT_PROP_DBUS_OBJECT, dbus_object,
	                    DBUSMENU_CLIENT_PROP_DBUS_NAME, dbus_name,
	                    NULL);
}

/**
	dbusmenu_gtkmenu_get_client:
	@menu: The #DbusmenuGtkMenu to get the client from

	An accessor for the client that this menu is using to
	communicate with the server.

	Return value: A valid #DbusmenuGtkClient or NULL on error.
*/
DbusmenuGtkClient *
dbusmenu_gtkmenu_get_client (DbusmenuGtkMenu * menu)
{
	g_return_val_if_fail(DBUSMENU_IS_GTKMENU(menu), NULL);
	DbusmenuGtkMenuPrivate * priv = DBUSMENU_GTKMENU_GET_PRIVATE(menu);
	return priv->client;
}
