#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stddef.h>
#include <string.h>
#include <assert.h>

#include <sys/socket.h>
#include <sys/ioctl.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <net/if.h>
#include <arpa/inet.h>

#include "ip4.h"
#include "rtnetlink.h"

int main()
{
  int ret;

  int fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
  if (fd < 0) {
    perror("socket");
    exit(EXIT_FAILURE);
  }

  struct sockaddr_nl bsa = { .nl_family = AF_NETLINK };
  ret = bind(fd, (struct sockaddr *)&bsa, (sizeof (sockaddr_nl)));
  if (ret < 0) {
    perror("bind");
    exit(EXIT_FAILURE);
  }

  struct sockaddr_nl gsa;
  socklen_t addrlen = (sizeof (sockaddr_nl));
  ret = getsockname(fd, (struct sockaddr *)&gsa, &addrlen);
  if (ret < 0) {
    perror("getsockname");
    exit(EXIT_FAILURE);
  }

  //////////////////////////////////////////////////////////////////////
  // interface index
  //////////////////////////////////////////////////////////////////////

  struct ifreq if_index = {};
  strncpy(if_index.ifr_name, interface_name, IFNAMSIZ - 1);
  int iret = ioctl(fd, SIOCGIFINDEX, &if_index);
  if (iret < 0) {
    perror("ioctl(SIOCGIFINDEX)");
    exit(EXIT_FAILURE);
  }
  printf("ifa_index %d\n", if_index.ifr_ifindex);

  //////////////////////////////////////////////////////////////////////
  // message
  //////////////////////////////////////////////////////////////////////

  int rtrets = rtnetlink::send_getaddr(fd, if_index.ifr_ifindex);
  if (rtrets < 0) {
    exit(EXIT_FAILURE);
  }

  const int out_length = 64;
  rtnetlink::newaddr out[out_length];
  int rtreth = rtnetlink::handle_getaddr(fd, if_index.ifr_ifindex, out, out_length);
  if (rtreth < 0) {
    exit(EXIT_FAILURE);
  }

  for (int i = 0; i < rtreth; i++) {
    printf("out[%d] prefixlen %d\n", i, out[i].ifa_prefixlen);
    printf("out[%d] local %s\n", i, ip4::tostr(out[i].local));
    printf("out[%d] address %s\n", i, ip4::tostr(out[i].address));

    // del
    {
      printf("del\n");
      int dret = rtnetlink::send_typeaddr(fd, RTM_DELADDR, if_index.ifr_ifindex,
                                          out[i].ifa_prefixlen, out[i].local, out[i].address);
      if (dret < 0) {
        exit(EXIT_FAILURE);
      }
      int eret = rtnetlink::handle_error(fd);
      if (eret < 0) {
        exit(EXIT_FAILURE);
      }
    }

    // new
    {
      printf("new\n");
      int dret = rtnetlink::send_typeaddr(fd, RTM_NEWADDR, if_index.ifr_ifindex,
                                          out[i].ifa_prefixlen, out[i].local, out[i].address);
      if (dret < 0) {
        exit(EXIT_FAILURE);
      }
      int eret = rtnetlink::handle_error(fd);
      if (eret < 0) {
        exit(EXIT_FAILURE);
      }
    }
  }

  // newroute
  {
    printf("newroute\n");
    uint32_t gateway;
    int ret = inet_pton(AF_INET, "192.168.1.1", (void *)&gateway);
    assert(ret == 1);

    int dret = rtnetlink::send_newroute(fd, if_index.ifr_ifindex, gateway);
    if (dret < 0) {
      exit(EXIT_FAILURE);
    }
    int eret = rtnetlink::handle_error(fd);
    if (eret < 0) {
      exit(EXIT_FAILURE);
    }
  }

  return 0;
}