/*
 * Copyright (c) 2008, Swedish Institute of Computer Science.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * This file is part of the Contiki operating system.
 *
 * $Id: sicslowmac.c,v 1.4 2009/09/18 16:37:17 nifi Exp $
 */


/**
 * \file
 *         MAC interface for packaging radio packets into 802.15.4 frames
 *
 * \author
 *         Adam Dunkels <adam@sics.se>
 *         Eric Gnoske <egnoske@gmail.com>
 *         Blake Leverett <bleverett@gmail.com>
 *         Niclas Finne <nfi@sics.se>
 *         Joakim Eriksson <joakime@sics.se>
 */

#include <string.h>
#include "net/mac/sicslowmac.h"
#include "net/mac/frame802154.h"
#include "net/rime/packetbuf.h"
#include "lib/random.h"

#define DEBUG 0

#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#define PRINTADDR(addr) PRINTF(" %02x%02x:%02x%02x:%02x%02x:%02x%02x ", ((uint8_t *)addr)[0], ((uint8_t *)addr)[1], ((uint8_t *)addr)[2], ((uint8_t *)addr)[3], ((uint8_t *)addr)[4], ((uint8_t *)addr)[5], ((uint8_t *)addr)[6], ((uint8_t *)addr)[7])
#else
#define PRINTF(...)
#define PRINTADDR(addr)
#endif

/**  \brief The sequence number (0x00 - 0xff) added to the transmitted
 *   data or MAC command frame. The default is a random value within
 *   the range.
 */
static uint8_t mac_dsn;

/**  \brief The 16-bit identifier of the PAN on which the device is
 *   sending to.  If this value is 0xffff, the device is not
 *   associated.
 */
static uint16_t mac_dst_pan_id = IEEE802154_PANID;

/**  \brief The 16-bit identifier of the PAN on which the device is
 *   operating.  If this value is 0xffff, the device is not
 *   associated.
 */
static uint16_t mac_src_pan_id = IEEE802154_PANID;

static const struct radio_driver *radio;
static void (* receiver_callback)(const struct mac_driver *);
/*---------------------------------------------------------------------------*/
static int
is_broadcast_addr(uint8_t mode, uint8_t *addr)
{
  int i = mode == FRAME802154_SHORTADDRMODE ? 2 : 8;
  while(i-- > 0) {
    if(addr[i] != 0xff) {
      return 0;
    }
  }
  return 1;
}
/*---------------------------------------------------------------------------*/
static int
send_packet(void)
{
  frame802154_t params;
  uint8_t len;

  /* init to zeros */
  memset(&params, 0, sizeof(params));

  /* Build the FCF. */
  params.fcf.frame_type = FRAME802154_DATAFRAME;
  params.fcf.security_enabled = 0;
  params.fcf.frame_pending = 0;
  params.fcf.ack_required = packetbuf_attr(PACKETBUF_ATTR_RELIABLE);
  params.fcf.panid_compression = 0;

  /* Insert IEEE 802.15.4 (2003) version bit. */
  params.fcf.frame_version = FRAME802154_IEEE802154_2003;

  /* Increment and set the data sequence number. */
  params.seq = mac_dsn++;

  /* Complete the addressing fields. */
  /**
     \todo For phase 1 the addresses are all long. We'll need a mechanism
     in the rime attributes to tell the mac to use long or short for phase 2.
  */
  params.fcf.src_addr_mode = FRAME802154_LONGADDRMODE;
  params.dest_pid = mac_dst_pan_id;

  /*
   *  If the output address is NULL in the Rime buf, then it is broadcast
   *  on the 802.15.4 network.
   */
  if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_null)) {
    /* Broadcast requires short address mode. */
    params.fcf.dest_addr_mode = FRAME802154_SHORTADDRMODE;
    params.dest_addr.u8[0] = 0xFF;
    params.dest_addr.u8[1] = 0xFF;

  } else {
    rimeaddr_copy(&params.dest_addr, packetbuf_addr(PACKETBUF_ADDR_RECEIVER));
    params.fcf.dest_addr_mode = FRAME802154_LONGADDRMODE;
  }

  /* Set the source PAN ID to the global variable. */
  params.src_pid = mac_src_pan_id;

  /*
   * Set up the source address using only the long address mode for
   * phase 1.
   */
  rimeaddr_copy(&params.src_addr, &rimeaddr_node_addr);

  params.payload = packetbuf_dataptr();
  params.payload_len = packetbuf_datalen();
  len = frame802154_hdrlen(&params);
  if(packetbuf_hdralloc(len)) {
    frame802154_create(&params, packetbuf_hdrptr(), len);

    PRINTF("6MAC-UT: %2X", params.fcf.frame_type);
    PRINTADDR(params.dest_addr.u8);
    PRINTF("%u %u (%u)\n", len, packetbuf_datalen(), packetbuf_totlen());

    return radio->send(packetbuf_hdrptr(), packetbuf_totlen());
  } else {
    PRINTF("6MAC-UT: too large header: %u\n", len);
  }
  return 0;
}
/*---------------------------------------------------------------------------*/
static void
input_packet(const struct radio_driver *d)
{
  if(receiver_callback) {
    receiver_callback(&sicslowmac_driver);
  }
}
/*---------------------------------------------------------------------------*/
static int
read_packet(void)
{
  frame802154_t frame;
  int len;
  packetbuf_clear();
  len = radio->read(packetbuf_dataptr(), PACKETBUF_SIZE);
  if(len > 0) {
    packetbuf_set_datalen(len);
    if(frame802154_parse(packetbuf_dataptr(), len, &frame) &&
       packetbuf_hdrreduce(len - frame.payload_len)) {
      if(frame.fcf.dest_addr_mode) {
        if(frame.dest_pid != mac_src_pan_id &&
           frame.dest_pid != FRAME802154_BROADCASTPANDID) {
          /* Not broadcast or for our PAN */
          PRINTF("6MAC: for another pan %u\n", frame.dest_pid);
          return 0;
        }
        if(!is_broadcast_addr(frame.fcf.dest_addr_mode, frame.dest_addr.u8)) {
          packetbuf_set_addr(PACKETBUF_ADDR_RECEIVER, &frame.dest_addr);
          if(!rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER),
                           &rimeaddr_node_addr)) {
            /* Not for this node */
            PRINTF("6MAC: not for us\n");
            return 0;
          }
        }
      }
      packetbuf_set_addr(PACKETBUF_ADDR_SENDER, &frame.src_addr);

      PRINTF("6MAC-IN: %2X", frame.fcf.frame_type);
      PRINTADDR(packetbuf_addr(PACKETBUF_ADDR_SENDER));
      PRINTADDR(packetbuf_addr(PACKETBUF_ADDR_RECEIVER));
      PRINTF("%u\n", packetbuf_datalen());
      return packetbuf_datalen();
    } else {
      PRINTF("6MAC: failed to parse hdr\n");
    }
  }
  return 0;
}
/*---------------------------------------------------------------------------*/
static void
set_receive_function(void (* recv)(const struct mac_driver *))
{
  receiver_callback = recv;
}
/*---------------------------------------------------------------------------*/
static int
on(void)
{
  return radio->on();
}
/*---------------------------------------------------------------------------*/
static int
off(int keep_radio_on)
{
  if(keep_radio_on) {
    return radio->on();
  } else {
    return radio->off();
  }
}
/*---------------------------------------------------------------------------*/
const struct mac_driver sicslowmac_driver = {
  "sicslowmac",
  sicslowmac_init,
  send_packet,
  read_packet,
  set_receive_function,
  on,
  off,
};
/*---------------------------------------------------------------------------*/
const struct mac_driver *
sicslowmac_init(const struct radio_driver *d)
{
  mac_dsn = random_rand() % 256;

  radio = d;
  radio->set_receive_function(input_packet);
  radio->on();
  return &sicslowmac_driver;
}
/*---------------------------------------------------------------------------*/
