/*
 *
 *  Wireless daemon for Linux
 *
 *  Copyright (C) 2017  Intel Corporation. All rights reserved.
 *
 *  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 St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

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

#include <ell/ell.h>

#include "dbus-proxy.h"
#include "display.h"

#define IWD_SERVICE		"net.connman.iwd"
#define IWD_ROOT_PATH		"/"

struct proxy_interface {
	void *data;
	char *path;
	const struct proxy_interface_type *type;
};

static struct l_dbus *dbus;

static struct l_queue *proxy_interfaces;
static struct l_queue *proxy_interface_types;

static void interface_update_properties(struct proxy_interface *proxy,
					struct l_dbus_message_iter *changed,
					struct l_dbus_message_iter *invalidated)
{
}

static bool dbus_message_has_error(struct l_dbus_message *message)
{
	const char *name;
	const char *text;

	if (l_dbus_message_get_error(message, &name, &text)) {
		display_error(text);
		return true;
	}

	return false;
}

static bool interface_match_by_type_name(const void *a, const void *b)
{
	const struct proxy_interface_type *type = a;
	const char *interface = b;

	return !strcmp(type->interface, interface);
}

struct proxy_interface *proxy_interface_find(const char *interface,
							const char *path)
{
	const struct l_queue_entry *entry;

	if (!interface || !path)
		return NULL;

	for (entry = l_queue_get_entries(proxy_interfaces); entry;
							entry = entry->next) {
		struct proxy_interface *proxy = entry->data;

		if (strcmp(proxy->path, path))
			continue;

		if (strcmp(proxy->type->interface, interface))
			continue;

		return proxy;
	}

	return NULL;
}

static void proxy_interface_bind_dependencies(const char *path)
{
}

static void proxy_interface_unbind_dependencies(
					const struct proxy_interface *proxy)
{
}

static bool is_ignorable(const char *interface)
{
	size_t i;

	static const struct {
		const char *interface;
	} interfaces_to_ignore[] = {
		{ L_DBUS_INTERFACE_OBJECT_MANAGER },
		{ L_DBUS_INTERFACE_INTROSPECTABLE },
		{ }
	};

	for (i = 0; interfaces_to_ignore[i].interface; i++)
		if (!strcmp(interfaces_to_ignore[i].interface, interface))
			return true;

	return false;
}

static void proxy_interface_create(const char *path,
					struct l_dbus_message_iter *interfaces)
{
	const char *interface;
	struct l_dbus_message_iter properties;
	struct proxy_interface *proxy;
	struct proxy_interface_type *interface_type;

	if (!path)
		return;

	while (l_dbus_message_iter_next_entry(interfaces, &interface,
								&properties)) {
		interface_type = l_queue_find(proxy_interface_types,
						interface_match_by_type_name,
						interface);

		if (!interface_type) {
			if (!is_ignorable(interface))
				l_debug("Unknown DBus interface type %s",
								interface);

			continue;
		}

		proxy = proxy_interface_find(interface_type->interface, path);

		if (proxy) {
			interface_update_properties(proxy, &properties, NULL);

			continue;
		}

		proxy = l_new(struct proxy_interface, 1);
		proxy->path = l_strdup(path);
		proxy->type = interface_type;

		if (interface_type->ops->create) {
			proxy->data = interface_type->ops->create();

			interface_update_properties(proxy, &properties, NULL);
		}

		l_queue_push_tail(proxy_interfaces, proxy);
	}

	proxy_interface_bind_dependencies(path);
}

static void interfaces_added_callback(struct l_dbus_message *message,
								void *user_data)
{
	const char *path;
	struct l_dbus_message_iter object;

	if (dbus_message_has_error(message))
		return;

	l_dbus_message_get_arguments(message, "oa{sa{sv}}", &path, &object);

	proxy_interface_create(path, &object);
}

static void interfaces_removed_callback(struct l_dbus_message *message,
								void *user_data)
{
	const char *interface;
	const char *path;
	struct l_dbus_message_iter interfaces;
	struct proxy_interface *proxy;

	if (dbus_message_has_error(message))
		return;

	l_dbus_message_get_arguments(message, "oas", &path, &interfaces);

	while (l_dbus_message_iter_next_entry(&interfaces, &interface)) {
		proxy = proxy_interface_find(interface, path);

		if (!proxy)
			continue;

		proxy_interface_unbind_dependencies(proxy);

		l_queue_remove(proxy_interfaces, proxy);
	}
}

static void get_managed_objects_callback(struct l_dbus_message *message,
								void *user_data)
{
	struct l_dbus_message_iter objects;
	struct l_dbus_message_iter object;
	const char *path;

	if (dbus_message_has_error(message)) {
		l_error("Failed to retrieve IWD dbus objects");

		return;
	}

	l_dbus_message_get_arguments(message, "a{oa{sa{sv}}}", &objects);

	while (l_dbus_message_iter_next_entry(&objects, &path, &object))
		proxy_interface_create(path, &object);

}

static void service_appeared_callback(struct l_dbus *dbus, void *user_data)
{
	l_dbus_add_signal_watch(dbus, IWD_SERVICE, IWD_ROOT_PATH,
					L_DBUS_INTERFACE_OBJECT_MANAGER,
					"InterfacesAdded", L_DBUS_MATCH_NONE,
					interfaces_added_callback, NULL);

	l_dbus_add_signal_watch(dbus, IWD_SERVICE, IWD_ROOT_PATH,
					L_DBUS_INTERFACE_OBJECT_MANAGER,
					"InterfacesRemoved", L_DBUS_MATCH_NONE,
					interfaces_removed_callback, NULL);

	l_dbus_method_call(dbus, IWD_SERVICE, IWD_ROOT_PATH,
					L_DBUS_INTERFACE_OBJECT_MANAGER,
					"GetManagedObjects", NULL,
					get_managed_objects_callback,
					NULL, NULL);
}

static void service_disappeared_callback(struct l_dbus *dbus,
							void *user_data)
{
}

static void dbus_disconnect_callback(void *user_data)
{
	l_main_quit();
}

static void proxy_interface_destroy(void *data)
{
}

bool dbus_proxy_init(void)
{
	if (dbus)
		return true;

	dbus = l_dbus_new_default(L_DBUS_SYSTEM_BUS);
	if (!dbus)
		return false;

	proxy_interface_types = l_queue_new();
	proxy_interfaces = l_queue_new();

	l_dbus_set_disconnect_handler(dbus, dbus_disconnect_callback, NULL,
									NULL);

	l_dbus_add_service_watch(dbus, IWD_SERVICE, service_appeared_callback,
						service_disappeared_callback,
						NULL, NULL);

	return true;
}

bool dbus_proxy_exit(void)
{
	l_queue_destroy(proxy_interface_types, NULL);
	proxy_interface_types = NULL;

	l_queue_destroy(proxy_interfaces, proxy_interface_destroy);
	proxy_interfaces = NULL;

	l_dbus_destroy(dbus);
	dbus = NULL;

	return true;
}