/*
 * Copyright (c) 2009, 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.
 *
 */

#include "contiki.h"
#include "contiki-conf.h"
#include "shell-rime.h"

#include "dev/leds.h"

#include "lib/crc16.h"
#include "lib/random.h"

#include "net/rime/rime.h"
#include "net/rime/unicast.h"

#include "net/rime/timesynch.h"

#if CONTIKI_TARGET_NETSIM
#include "ether.h"
#endif /* CONTIKI_TARGET_NETSIM */

#include <stdio.h>
#ifndef HAVE_SNPRINTF
int snprintf(char *str, size_t size, const char *format, ...);
#endif /* HAVE_SNPRINTF */
#include <string.h>

#define CMDMSG_HDR_SIZE 2

struct cmd_msg {
  uint16_t crc;
  char sendcmd[1];
};

static struct unicast_conn uc;
/*---------------------------------------------------------------------------*/
PROCESS(shell_sendcmd_process, "sendcmd");
PROCESS(shell_sendcmd_server_process, "sendcmd server");
SHELL_COMMAND(sendcmd_command,
          "sendcmd",
          "sendcmd <node addr> <command>: send a command to the specified one-hop node",
          &shell_sendcmd_process);
/*---------------------------------------------------------------------------*/
PROCESS_THREAD(shell_sendcmd_server_process, ev, data)
{
  static struct process *child_command;
  int err;
  PROCESS_BEGIN();

  /* XXX: direct output to null. */
  /*  printf("sendcmd server got command string '%s'\n", (char *)data);*/
  err = shell_start_command(data, strlen((char * )data), NULL, &child_command);
  if(err == SHELL_FOREGROUND && process_is_running(child_command)) {
    PROCESS_WAIT_EVENT_UNTIL(ev == PROCESS_EVENT_EXIT ||
                 (ev == PROCESS_EVENT_EXITED &&
                  data == child_command));
    if(ev == PROCESS_EVENT_EXIT) {
      process_exit(child_command);
    }
  }

  PROCESS_END();
}
/*---------------------------------------------------------------------------*/
PROCESS_THREAD(shell_sendcmd_process, ev, data)
{
  struct cmd_msg  *msg;
  int len;
  linkaddr_t addr;
  const char *nextptr;
  char buf[32];

  PROCESS_BEGIN();

  addr.u8[0] = shell_strtolong(data, &nextptr);
  if(nextptr == data || *nextptr != '.') {
    shell_output_str(&sendcmd_command,
             "sendcmd <node addr>: receiver must be specified", "");
    PROCESS_EXIT();
  }
  ++nextptr;
  addr.u8[1] = shell_strtolong(nextptr, &nextptr);

  snprintf(buf, sizeof(buf), "%d.%d", addr.u8[0], addr.u8[1]);
  shell_output_str(&sendcmd_command, "Sending command to ", buf);

  /* Get the length of the command line, excluding a terminating NUL character. */
  len = strlen((char *)nextptr);

  /* Check the length of the command line to see that it is small
     enough to fit in a packet. We count with 32 bytes of header,
     which may be a little too much, but at least we are on the safe
     side. */
  if(len > PACKETBUF_SIZE - 32) {
    snprintf(buf, sizeof(buf), "%d", len);
    shell_output_str(&sendcmd_command, "command line too large: ", buf);
    PROCESS_EXIT();
  }

  packetbuf_clear();
  msg = packetbuf_dataptr();
  packetbuf_set_datalen(len + 1 + CMDMSG_HDR_SIZE);
  strcpy(msg->sendcmd, nextptr);

  /* Terminate the string with a NUL character. */
  msg->sendcmd[len] = 0;
  msg->crc = crc16_data((unsigned char *)msg->sendcmd, len, 0);
  /*    printf("sendcmd sending '%s'\n", msg->sendcmd);*/
  unicast_send(&uc, &addr);

  PROCESS_END();
}
/*---------------------------------------------------------------------------*/
static void
recv_uc(struct unicast_conn *c, const linkaddr_t *from)
{
  struct cmd_msg *msg;
  uint16_t crc;
  int len;

  msg = packetbuf_dataptr();

  if(packetbuf_datalen() > 1 + CMDMSG_HDR_SIZE) {

    /* First ensure that the old process is killed. */
    process_exit(&shell_sendcmd_server_process);

    len = packetbuf_datalen() - 1 - CMDMSG_HDR_SIZE;

    /* Make sure that the incoming command is null-terminated. */
    msg->sendcmd[len] = 0;
    memcpy(&crc, &msg->crc, sizeof(crc));

    if(crc == crc16_data((unsigned char *)msg->sendcmd, len, 0)) {
      /* Start the server process with the incoming command. */
      process_start(&shell_sendcmd_server_process, (void *)msg->sendcmd);
    }
  }
}
static const struct unicast_callbacks unicast_callbacks = { recv_uc };
/*---------------------------------------------------------------------------*/
void
shell_rime_sendcmd_init(void)
{
  unicast_open(&uc, SHELL_RIME_CHANNEL_SENDCMD, &unicast_callbacks);
  shell_register_command(&sendcmd_command);
}
/*---------------------------------------------------------------------------*/