/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2025, Muhammad Saheed <saheed@FreeBSD.org>
 */

#include <netlink/netlink.h>
#include <netlink/netlink_snl.h>
#include <netlink/route/common.h>
#include <netlink/route/interface.h>

#include "libifconfig.h"
#include "libifconfig_internal.h"

static int ifconfig_modify_flags(ifconfig_handle_t *h, const char *ifname,
    int ifi_flags, int ifi_change);

static int
ifconfig_modify_flags(ifconfig_handle_t *h, const char *ifname, int ifi_flags,
    int ifi_change)
{
        int ret = 0;
        struct snl_state ss;
        struct snl_writer nw;
        struct nlmsghdr *hdr;
        struct ifinfomsg *ifi;
        struct snl_errmsg_data e = { 0 };

        if (!snl_init(&ss, NETLINK_ROUTE)) {
                ifconfig_error(h, NETLINK, ENOTSUP);
                return (-1);
        }

        snl_init_writer(&ss, &nw);
        hdr = snl_create_msg_request(&nw, NL_RTM_NEWLINK);
        ifi = snl_reserve_msg_object(&nw, struct ifinfomsg);
        snl_add_msg_attr_string(&nw, IFLA_IFNAME, ifname);

        ifi->ifi_flags = ifi_flags;
        ifi->ifi_change = ifi_change;

        hdr = snl_finalize_msg(&nw);
        if (hdr == NULL) {
                ifconfig_error(h, NETLINK, ENOMEM);
                ret = -1;
                goto out;
        }

        if (!snl_send_message(&ss, hdr)) {
                ifconfig_error(h, NETLINK, EIO);
                ret = -1;
                goto out;
        }

        if (!snl_read_reply_code(&ss, hdr->nlmsg_seq, &e)) {
                ifconfig_error(h, NETLINK, e.error);
                ret = -1;
                goto out;
        }

out:
        snl_free(&ss);
        return (ret);
}

int
ifconfig_set_up(ifconfig_handle_t *h, const char *ifname, bool up)
{
        int flag = up ? IFF_UP : ~IFF_UP;

        return (ifconfig_modify_flags(h, ifname, flag, IFF_UP));
}