#!/usr/bin/python3.7
# !coding:utf-8
__author__ = 'hsz'
__date__ = 'Thu Feb 27 22:41:15 EST 2020'

import time
import struct
import socket
import select
import sys


def chesksum(data):
  """
  校验
  """
  n = len(data)
  m = n % 2
  sum = 0
  for i in range(0, n - m, 2):
    sum += (data[i]) + ((data[i + 1]) << 8) # 传入data以每两个字节（十六进制）通过ord转十进制，第一字节在低位，第二个字节在高位
  if m:
    sum += (data[-1])
  # 将高于16位与低16位相加
  sum = (sum  16) + (sum & 0xffff)
  sum += (sum  16) # 如果还有高于16位，将继续与低16位相加
  answer = ~sum & 0xffff
  # 主机字节序转网络字节序列（参考小端序转大端序）
  answer = answer  8 | (answer << 8 & 0xff00)
  return answer

  '''
  连接套接字,并将数据发送到套接字
  '''


def raw_socket(dst_addr, imcp_packet):
  rawsocket = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.getprotobyname("icmp"))
  send_request_ping_time = time.time()
  # send data to the socket
  rawsocket.sendto(imcp_packet, (dst_addr, 80))
  return send_request_ping_time, rawsocket, dst_addr

  '''
  request ping
  '''


def request_ping(data_type, data_code, data_checksum, data_ID, data_Sequence, payload_body):
  # 把字节打包成二进制数据
  imcp_packet = struct.pack('>BBHHH32s', data_type, data_code, data_checksum, data_ID, data_Sequence, payload_body)
  icmp_chesksum = chesksum(imcp_packet) # 获取校验和
  imcp_packet = struct.pack('>BBHHH32s', data_type, data_code, icmp_chesksum, data_ID, data_Sequence, payload_body)
  return imcp_packet
  '''
  reply ping
  '''


def reply_ping(send_request_ping_time, rawsocket, data_Sequence, timeout=2):
  while True:
    started_select = time.time()
    what_ready = select.select([rawsocket], [], [], timeout)
    wait_for_time = (time.time() - started_select)
    if what_ready[0] == []: # Timeout
      return -1
    time_received = time.time()
    received_packet, addr = rawsocket.recvfrom(1024)
    icmpHeader = received_packet[20:28]
    type, code, checksum, packet_id, sequence = struct.unpack(
      ">BBHHH", icmpHeader
    )
    if type == 0 and sequence == data_Sequence:
      return time_received - send_request_ping_time
    timeout = timeout - wait_for_time
    if timeout <= 0:
      return -1

  '''
  实现 ping 主机/ip
  '''


def ping(host):
  data_type = 8 # ICMP Echo Request
  data_code = 0 # must be zero
  data_checksum = 0 # "...with value 0 substituted for this field..."
  data_ID = 0 # Identifier
  data_Sequence = 1 # Sequence number
  payload_body = b'abcdefghijklmnopqrstuvwabcdefghi' # data
  dst_addr = socket.gethostbyname(host) # 将主机名转ipv4地址格式，返回以ipv4地址格式的字符串，如果主机名称是ipv4地址，则它将保持不变
  print("正在 Ping {0} [{1}] 具有 32 字节的数据:".format(host, dst_addr))
  for i in range(0, 4):
    icmp_packet = request_ping(data_type, data_code, data_checksum, data_ID, data_Sequence + i, payload_body)
    send_request_ping_time, rawsocket, addr = raw_socket(dst_addr, icmp_packet)
    times = reply_ping(send_request_ping_time, rawsocket, data_Sequence + i)
    if times > 0:
      print("来自 {0} 的回复: 字节=32 时间={1}ms".format(addr, int(times * 1000)))
      time.sleep(0.7)
    else:
      print("请求超时。")


if __name__ == "__main__":
  # if len(sys.argv) < 2:
  #   sys.exit('Usage: ping.py <host>')
  ping('www.baidu.com') # sys.argv[1]

from ping3 import ping


def ping_host(ip):
  """
  获取节点的延迟的作用
  :param node:
  :return:
  """
  ip_address = ip
  response = ping(ip_address)
  print(response)
  if response is not None:
    delay = int(response * 1000)
    print(delay, "延迟")
    # 下面两行新增的


ping_host('www.baidu.com')