/**
 * @file
 * Ping sender module
 *
 */

/*
 * 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. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 lwIP TCP/IP stack.
 * 
 */

/** 
 * This is an example of a "ping" sender (with raw API and socket API).
 * It can be used as a start point to maintain opened a network connection, or
 * like a network "watchdog" for your device.
 *
 */

/*
 * copyright (c) 2010 - 2011 Espressif System
 */

#include "lwip/opt.h"

#if LWIP_RAW /* don't build if not configured for use in lwipopts.h */

#include "lwip/mem.h"
#include "lwip/raw.h"
#include "lwip/icmp.h"
#include "lwip/netif.h"
#include "lwip/sys.h"
#include "lwip/timers.h"
#include "lwip/inet_chksum.h"
#include "os_type.h"
#include "osapi.h"

#include "lwip/app/ping.h"

#if PING_USE_SOCKETS
#include "lwip/sockets.h"
#include "lwip/inet.h"
#endif /* PING_USE_SOCKETS */

/* ping variables */
static u16_t ping_seq_num = 0;
static u32_t ping_time;

static void ICACHE_FLASH_ATTR ping_timeout(void* arg)
{
	struct ping_msg *pingmsg = (struct ping_msg *)arg;
	pingmsg->timeout_count ++;
	if (pingmsg->ping_opt->recv_function == NULL){
		os_printf("ping timeout\n");
	} else {
		struct ping_resp pingresp;
		os_bzero(&pingresp, sizeof(struct ping_resp));
		pingresp.ping_err = -1;
		pingmsg->ping_opt->recv_function(pingmsg->ping_opt, (void*)&pingresp);
	}
}

/** Prepare a echo ICMP request */
static void ICACHE_FLASH_ATTR
ping_prepare_echo( struct icmp_echo_hdr *iecho, u16_t len)
{
  size_t i = 0;
  size_t data_len = len - sizeof(struct icmp_echo_hdr);

  ICMPH_TYPE_SET(iecho, ICMP_ECHO);
  ICMPH_CODE_SET(iecho, 0);
  iecho->chksum = 0;
  iecho->id     = PING_ID;
  ++ ping_seq_num;
  iecho->seqno  = htons(ping_seq_num);

  /* fill the additional data buffer with some data */
  for(i = 0; i < data_len; i++) {
    ((char*)iecho)[sizeof(struct icmp_echo_hdr) + i] = (char)i;
  }

  iecho->chksum = inet_chksum(iecho, len);
}

static void ICACHE_FLASH_ATTR
ping_prepare_er(struct icmp_echo_hdr *iecho, u16_t len)
{

	ICMPH_TYPE_SET(iecho, ICMP_ER);
	ICMPH_CODE_SET(iecho, 0);
	iecho->chksum = 0;

	iecho->chksum = inet_chksum(iecho, len);
}

/* Ping using the raw ip */
static u8_t ICACHE_FLASH_ATTR
ping_recv(void *arg, struct raw_pcb *pcb, struct pbuf *p, ip_addr_t *addr)
{
  struct icmp_echo_hdr *iecho = NULL;
  static u16_t seqno = 0;
  struct ping_msg *pingmsg = (struct ping_msg*)arg;

  LWIP_UNUSED_ARG(arg);
  LWIP_UNUSED_ARG(pcb);
  LWIP_UNUSED_ARG(addr);
  LWIP_ASSERT("p != NULL", p != NULL);

  if (pbuf_header( p, -PBUF_IP_HLEN)==0) {
    iecho = (struct icmp_echo_hdr *)p->payload;

    if ((iecho->id == PING_ID) && (iecho->seqno == htons(ping_seq_num)) && iecho->type == ICMP_ER) {
      LWIP_DEBUGF( PING_DEBUG, ("ping: recv "));
      ip_addr_debug_print(PING_DEBUG, addr);
      LWIP_DEBUGF( PING_DEBUG, (" %"U32_F" ms\n", (sys_now()-ping_time)));
	  if (iecho->seqno != seqno){
		  /* do some ping result processing */
		  {
			  struct ip_hdr *iphdr = NULL;
			  char ipaddrstr[16];
			  ip_addr_t source_ip;
			  sys_untimeout(ping_timeout, pingmsg);
			  os_bzero(&source_ip, sizeof(ip_addr_t));
			  os_bzero(ipaddrstr, sizeof(ipaddrstr));
			  uint32 delay = system_relative_time(pingmsg->ping_sent);
			  delay /= PING_COARSE;
			  iphdr = (struct ip_hdr*)((u8*)iecho - PBUF_IP_HLEN);
			  source_ip.addr = iphdr->src.addr;
			  ipaddr_ntoa_r(&source_ip,ipaddrstr, sizeof(ipaddrstr));
			  if (pingmsg->ping_opt->recv_function == NULL){
				  os_printf("recv %s: byte = %d, time = %d ms, seq = %d\n",ipaddrstr, PING_DATA_SIZE, delay, ntohs(iecho->seqno));
			  } else {
				  struct ping_resp pingresp;
				  os_bzero(&pingresp, sizeof(struct ping_resp));
				  pingresp.bytes = PING_DATA_SIZE;
				  pingresp.resp_time = delay;
				  pingresp.seqno = ntohs(iecho->seqno);
				  pingresp.ping_err = 0;
				  pingmsg->ping_opt->recv_function(pingmsg->ping_opt,(void*) &pingresp);
			  }
		  }
		  seqno = iecho->seqno;
	  }

      PING_RESULT(1);
      pbuf_free(p);
      return 1; /* eat the packet */
    }
//    } else if(iecho->type == ICMP_ECHO){
//        struct pbuf *q = NULL;
//        os_printf("receive ping request:seq=%d\n", ntohs(iecho->seqno));
//        q = pbuf_alloc(PBUF_IP, (u16_t)p->tot_len, PBUF_RAM);
//        if (q!=NULL) {
//            pbuf_copy(q, p);
//            iecho = (struct icmp_echo_hdr *)q->payload;
//            ping_prepare_er(iecho, q->tot_len);
//            raw_sendto(pcb, q, addr);
//            pbuf_free(q);
//        }
//        pbuf_free(p);
//        return 1;
//    }
  }

  return 0; /* don't eat the packet */
}

static void ICACHE_FLASH_ATTR
ping_send(struct raw_pcb *raw, ip_addr_t *addr)
{
  struct pbuf *p = NULL;
  struct icmp_echo_hdr *iecho = NULL;
  size_t ping_size = sizeof(struct icmp_echo_hdr) + PING_DATA_SIZE;

  LWIP_DEBUGF( PING_DEBUG, ("ping: send "));
  ip_addr_debug_print(PING_DEBUG, addr);
  LWIP_DEBUGF( PING_DEBUG, ("\n"));
  LWIP_ASSERT("ping_size <= 0xffff", ping_size <= 0xffff);

  p = pbuf_alloc(PBUF_IP, (u16_t)ping_size, PBUF_RAM);
  if (!p) {
    return;
  }
  if ((p->len == p->tot_len) && (p->next == NULL)) {
    iecho = (struct icmp_echo_hdr *)p->payload;

    ping_prepare_echo(iecho, (u16_t)ping_size);

    raw_sendto(raw, p, addr);
    ping_time = sys_now();
  }
  pbuf_free(p);
}

static void ICACHE_FLASH_ATTR
ping_coarse_tmr(void *arg)
{
	struct ping_msg *pingmsg = (struct ping_msg*)arg;
	struct ping_option *ping_opt= NULL;
	struct ping_resp pingresp;
	ip_addr_t ping_target;

	LWIP_ASSERT("ping_timeout: no pcb given!", pingmsg != NULL);
	ping_target.addr = pingmsg->ping_opt->ip;
	ping_opt = pingmsg->ping_opt;
	if (--pingmsg->sent_count != 0){
		pingmsg ->ping_sent = system_get_time();
		ping_send(pingmsg->ping_pcb, &ping_target);

		sys_timeout(PING_TIMEOUT_MS, ping_timeout, pingmsg);
		sys_timeout(pingmsg->coarse_time, ping_coarse_tmr, pingmsg);
	} else {
		uint32 delay = system_relative_time(pingmsg->ping_start);
		delay /= PING_COARSE;
		ping_seq_num = 0;
		if (ping_opt->sent_function == NULL){
			os_printf("ping %d, timeout %d, total payload %d bytes, %d ms\n",
					pingmsg->max_count, pingmsg->timeout_count, PING_DATA_SIZE*(pingmsg->max_count - pingmsg->timeout_count),delay);
		} else {
			os_bzero(&pingresp, sizeof(struct ping_resp));
			pingresp.total_count = pingmsg->max_count;
			pingresp.timeout_count = pingmsg->timeout_count;
			pingresp.total_bytes = PING_DATA_SIZE*(pingmsg->max_count - pingmsg->timeout_count);
			pingresp.total_time = delay;
			pingresp.ping_err = 0;
		}
		sys_untimeout(ping_coarse_tmr, pingmsg);
		raw_remove(pingmsg->ping_pcb);
		os_free(pingmsg);
		if (ping_opt->sent_function != NULL)
			ping_opt->sent_function(ping_opt,(uint8*)&pingresp);
	}
}

static bool ICACHE_FLASH_ATTR
ping_raw_init(struct ping_msg *pingmsg)
{
	if (pingmsg == NULL)
		return false;

	ip_addr_t ping_target;
	pingmsg->ping_pcb = raw_new(IP_PROTO_ICMP);
	LWIP_ASSERT("ping_pcb != NULL", pingmsg->ping_pcb != NULL);

	raw_recv(pingmsg->ping_pcb, ping_recv, pingmsg);
	raw_bind(pingmsg->ping_pcb, IP_ADDR_ANY);

	ping_target.addr = pingmsg->ping_opt->ip;
	pingmsg ->ping_sent = system_get_time();
	ping_send(pingmsg->ping_pcb, &ping_target);

	sys_timeout(PING_TIMEOUT_MS, ping_timeout, pingmsg);
	sys_timeout(pingmsg->coarse_time, ping_coarse_tmr, pingmsg);
	return true;
}

bool ICACHE_FLASH_ATTR
ping_start(struct ping_option *ping_opt)
{
	struct ping_msg *pingmsg = NULL;
	pingmsg = (struct ping_msg *)os_zalloc(sizeof(struct ping_msg));
	if (pingmsg == NULL || ping_opt == NULL)
		return false;

	pingmsg->ping_opt = ping_opt;
	if (ping_opt->count != 0)
		pingmsg->max_count = ping_opt->count;
	else
		pingmsg->max_count = DEFAULT_PING_MAX_COUNT;

	if (ping_opt->coarse_time != 0)
		pingmsg->coarse_time = ping_opt->coarse_time * PING_COARSE;
	else
		pingmsg->coarse_time = PING_COARSE;

	pingmsg->ping_start = system_get_time();
	pingmsg->sent_count = pingmsg->max_count;
	return ping_raw_init(pingmsg);
}

bool ICACHE_FLASH_ATTR
ping_regist_recv(struct ping_option *ping_opt, ping_recv_function ping_recv)
{
	if (ping_opt == NULL)
		return false;

	ping_opt ->recv_function = ping_recv;
	return true;
}

bool ICACHE_FLASH_ATTR
ping_regist_sent(struct ping_option *ping_opt, ping_sent_function ping_sent)
{
	if (ping_opt == NULL)
		return false;

	ping_opt ->sent_function = ping_sent;
	return true;
}

#endif /* LWIP_RAW */