#include "contiki.h"
#include "net/routing/routing.h"
#include "random.h"
#include "net/netstack.h"
#include "net/ipv6/simple-udp.h"

#include "sys/log.h"
#define LOG_MODULE "App"
#define LOG_LEVEL LOG_LEVEL_INFO

#define WITH_SERVER_REPLY  1
#define UDP_CLIENT_PORT	8765
#define UDP_SERVER_PORT	5678

#define SEND_INTERVAL		  (60 * CLOCK_SECOND)

static struct simple_udp_connection udp_conn;

/*---------------------------------------------------------------------------*/
PROCESS(udp_client_process, "UDP client");
AUTOSTART_PROCESSES(&udp_client_process);
/*---------------------------------------------------------------------------*/
static void
udp_rx_callback(struct simple_udp_connection *c,
         const uip_ipaddr_t *sender_addr,
         uint16_t sender_port,
         const uip_ipaddr_t *receiver_addr,
         uint16_t receiver_port,
         const uint8_t *data,
         uint16_t datalen)
{
  unsigned count = *(unsigned *)data;
  /* If tagging of traffic class is enabled tc will print number of
     transmission - otherwise it will be 0 */
  LOG_INFO("Received response %u (Max MAC Tx: %d) from ", count,
           uipbuf_get_attr(UIPBUF_ATTR_MAX_MAC_TRANSMISSIONS));
  LOG_INFO_6ADDR(sender_addr);
  LOG_INFO_("\n");
}
/*---------------------------------------------------------------------------*/
PROCESS_THREAD(udp_client_process, ev, data)
{
  static struct etimer periodic_timer;
  static unsigned count;
  uip_ipaddr_t dest_ipaddr;

  PROCESS_BEGIN();

  /* Initialize UDP connection */
  simple_udp_register(&udp_conn, UDP_CLIENT_PORT, NULL,
                      UDP_SERVER_PORT, udp_rx_callback);

  etimer_set(&periodic_timer, random_rand() % SEND_INTERVAL);
  while(1) {
    PROCESS_WAIT_EVENT_UNTIL(etimer_expired(&periodic_timer));

    if(NETSTACK_ROUTING.node_is_reachable() && NETSTACK_ROUTING.get_root_ipaddr(&dest_ipaddr)) {
      /* Set the number of transmissions to use for this packet -
         this can be used to create more reliable transmissions or
         less reliable than the default. Works end-to-end if
         UIP_CONF_TAG_TC_WITH_VARIABLE_RETRANSMISSIONS is set to 1.
       */
      uipbuf_set_attr(UIPBUF_ATTR_MAX_MAC_TRANSMISSIONS, 1 + count % 5);
      /* Send to DAG root */
      LOG_INFO("Sending request %u (Max MAC Tx: %d) to ", count,
        uipbuf_get_attr(UIPBUF_ATTR_MAX_MAC_TRANSMISSIONS));
      LOG_INFO_6ADDR(&dest_ipaddr);
      LOG_INFO_("\n");
      simple_udp_sendto(&udp_conn, &count, sizeof(count), &dest_ipaddr);
      count++;
    } else {
      LOG_INFO("Not reachable yet\n");
    }

    /* Add some jitter */
    etimer_set(&periodic_timer, SEND_INTERVAL
      - CLOCK_SECOND + (random_rand() % (2 * CLOCK_SECOND)));
  }

  PROCESS_END();
}
/*---------------------------------------------------------------------------*/