#!/usr/bin/env python2
#
# 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 json
import requests
from requests.packages.urllib3.exceptions import InsecureRequestWarning

requests.packages.urllib3.disable_warnings(InsecureRequestWarning)
import sys
import CLEUCreds

DHCP_BASE = 'https://dc1-dhcp.ciscolive.network:8443/web-services/rest/resource/Scope'
IDF_CNT = 98

HEADERS = {
    'authorization': CLEUCreds.JCLARKE_BASIC,
    'accept': 'application/json',
    'content-type': 'application/json'
}

if __name__ == '__main__':
    if len(sys.argv) != 4:
        sys.stderr.write(
            "usage: {} VLAN <IDF|CORE> START\n".format(sys.argv[0]))
        sys.exit(1)

    vlan = sys.argv[1]
    type = sys.argv[2].upper()
    start = sys.argv[3]

    if type != 'CORE' and type != 'IDF':
        sys.stderr.write("usage: {} VLAN <IDF|CORE> START\n".format(sys.argv[0]))
        sys.exit(1)

    istart = 1
    prefix = 'IDF-' + str(istart).zfill(3)
    rs = 1
    cnt = IDF_CNT

    if type == 'CORE':
        prefix = 'CORE-'
        rs = 0
        cnt = 0

    first_scope_name = '{}-{}'.format(prefix, vlan.upper())

    url = '{}/{}'.format(DHCP_BASE, first_scope_name)

    try:
        response = requests.request('GET', url, headers=HEADERS, verify=False)
        response.raise_for_status()
    except Exception as e:
        sys.stderr.write(
            'Failed to get first scope details for {}: {}\n'.format(first_scope_name, e))
        sys.exit(1)

    first_scope = response.json()
    end = first_scope['rangeList']['RangeItem'][0]['end'].split('.')[3]
    subnet = '.'.join(first_scope['subnet'].split('.')[0:2])

    policy = first_scope['policy']
    embedded_policy = None
    if 'embeddedPolicy' in first_scope:
        embedded_policy = first_scope['embeddedPolicy']

    for i in range(rs, cnt + 1):
        rstart = '{}.{}.{}'.format(subnet, i, start)
        eoctet = i
        if type == 'CORE':
            eoctet = 255

        rend = '{}.{}.{}'.format(subnet, eoctet, end)

        prefix = 'IDF-' + str(i).zfill(3)

        if embedded_policy is not None:
            embedded_policy = {
                'optionList': {
                    'OptionItem': [
                        {
                            'number': '3',
                            'value': '{}.{}.{}'.format(subnet, eoctet, str(254))
                        }
                    ]
                }
            }

        if type == 'CORE':
            prefix = 'CORE-'

        scope_name = '{}-{}'.format(prefix, vlan.upper())

        url = '{}/{}'.format(DHCP_BASE, scope_name)

        try:
            # print('Changing {} to start: {}, end: {}'.format(
            #    scope_name, start, end))

            payload = {
                'rangeList': {'RangeItem': [
                    {'start': rstart, 'end': rend}]},
                'policy': policy
            }
            if embedded_policy is not None:
                payload['embeddedPolicy'] = embedded_policy

            response = requests.request(
                'PUT', url, json=payload, headers=HEADERS, verify=False)
            response.raise_for_status()
        except Exception as e:
            sys.stderr.write(
                'Failed to update scope details for {}: {}\n'.format(scope_name, e))
            continue