#!/usr/bin/env python2.7
#
# Copyright (c) 2017-2019  Joe Clarke <jclarke@cisco.com>
# 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.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.

import requests
from requests.packages.urllib3.exceptions import InsecureRequestWarning

requests.packages.urllib3.disable_warnings(InsecureRequestWarning)
import json
import sys
import time
import os
from subprocess import call
from sparker import Sparker
import pprint
import re
from multiprocessing import Pool
import socket
import CLEUCreds

TOOL = 'tool.ciscolive.network'
CACHE_FILE = '/home/jclarke/cached_devs.dat'
PING_DEVS_FILE = '/home/jclarke/ping-devs.json'

TEXT_BAD = "**DANGER! DANGER!**: Pinger detected that device %s (IP: %s)%s is no longer reachable"
TEXT_GOOD = "_RELAX_: Pinger has detected that device %s (IP: %s)%s is now reachable again"

ROOM_NAME = 'Device Alarms'
TEAM_NAME = 'CL19 NOC Team'

excluded_devices = [r'^VHS-']

additional_devices = []


def check_prev(dev_dic, prev_devs, pstate='REACHABLE'):
    send_msg = False
    for pd in prev_devs:
        if pd['name'] == dev_dic['name']:
            if pd['reachability'] != pstate:
                send_msg = True
            break
    return send_msg


def know_device(dev_dic, prev_devs):
    for pd in prev_devs:
        if pd['name'] == dev_dic['name']:
            return True

    return False


def ping_device(dev):
    global TEAM_NAME, ROOM_NAME, TEXT_BAD, TEXT_GOOD, prev_devs, spark, excluded_devices

    dev_dic = {}

    dev_dic['name'] = dev['Hostname']
    dev_dic['ip'] = dev['IPAddress']
    if dev_dic['ip'] == '0.0.0.0':
        return None
    for exc in excluded_devices:
        if re.search(exc, dev_dic['name']) or re.search(exc, dev_dic['ip']):
            return None
    #print('Pinging {}'.format(dev_dic['name']))
    msg_text = TEXT_BAD
    send_msg = True
    if not dev['Reachable']:
        send_msg = know_device(dev_dic, prev_devs)
    for i in range(2):
        res = call(["/usr/local/sbin/fping",
                    "-q", "-r0", dev_dic['ip']])
        time.sleep(.5)
    if res != 0:
        dev_dic['reachability'] = 'UNREACHABLE'
        send_msg = check_prev(dev_dic, prev_devs, 'UNREACHABLE')
    else:
        dev_dic['reachability'] = 'REACHABLE'
        msg_text = TEXT_GOOD
        send_msg = check_prev(dev_dic, prev_devs)

    if send_msg:
        loc = ''
        if 'LocationDetail' in dev:
            loc = ' (Location: {})'.format(dev['LocationDetail'])
        message = msg_text % (dev_dic['name'], dev_dic['ip'], loc)
        spark.post_to_spark(TEAM_NAME, ROOM_NAME, message)

    return dev_dic


def get_devs(p):
    global TOOL, additional_devices

    url = "http://{}/get/switches/json".format(TOOL)

    devices = []
#    response = requests.request('GET', url)
    code = 200
#   code = response.status_code
    if code == 200:
        #j = json.loads(response.text)
        j = []

        for dev in additional_devices:
            ip = dev
            try:
                ip = socket.gethostbyname(dev)
            except:
                pass
            j.append({'Hostname': dev, 'IPAddress': ip, 'Reachable': True})

        results = [pool.apply_async(ping_device, [d]) for d in j]
        for res in results:
            retval = res.get()
            if retval is not None:
                devices.append(retval)

    return devices


if __name__ == '__main__':
    prev_devs = []
    if os.path.exists(CACHE_FILE):
        fd = open(CACHE_FILE, 'r')
        prev_devs = json.load(fd)
        fd.close()

    spark = Sparker(token=CLEUCreds.SPARK_TOKEN)

    try:
        fd = open(PING_DEVS_FILE, 'r')
        additional_devices = json.load(fd)
        fd.close()
    except:
        pass

    pool = Pool(20)
    devs = get_devs(pool)
    fd = open(CACHE_FILE, 'w')
    json.dump(devs, fd, ensure_ascii=False, indent=4)
    fd.close()