#!/usr/bin/python3

# ==============================================================================
# Copyright 2011 Amazon.com, Inc. or its affiliates. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ==============================================================================

import base64
import re
import uuid
import datetime
from optparse import OptionParser
import os
import sys

import cfnbootstrap
from cfnbootstrap import util
from cfnbootstrap.packages import requests
import json

parser = OptionParser(usage="usage: %prog [options] [Command Event Message]")

parser.add_option_group(util.get_proxy_options(parser))

parser.add_option("", "--event-handle", help="Event Handle URL",
                  type="string", dest="event_handle", default=os.environ.get('EVENT_HANDLE'))
parser.add_option("-e", "--event-id", help="An id that uniquely identifies the event for this command and listener",
                  type="string", dest="event_id", default=str(uuid.uuid4()))
parser.add_option("-t", "--event-timestamp", help="The time the event occurred, in ISO 8601 form ",
                  type="string", dest="event_timestamp", default=datetime.datetime.utcnow().isoformat())

parser.add_option("-d", "--dispatcher-id", help="The dispatcher ID",
                  type="string", dest="dispatcher_id", default=os.environ.get('DISPATCHER_ID'))
parser.add_option("-c", "--command-name", help="The command name",
                  type="string", dest="command_name", default=os.environ.get('CMD_NAME'))
parser.add_option("-i", "--invocation-id", help="The invocation ID",
                  type="string", dest="invocation_id", default=os.environ.get('INVOCATION_ID'))
parser.add_option("-l", "--listener-id", help="The listener ID",
                  type="string", dest="listener_id", default=os.environ.get('LISTENER_ID'))

(options, args) = parser.parse_args()

options.event_handle = options.event_handle if re.match(r'https?://.*', options.event_handle) \
    else base64.b64decode(options.event_handle)

if not re.match(r'https?://.*', options.event_handle):
    print("Error: Invalid EventHandle URL specified: %s" %
          options.event_handle, file=sys.stderr)
    sys.exit(1)


def fail_on_unspecified(value, name):
    if not value:
        print("Error: You must specify %s" % name, file=sys.stderr)
        parser.print_help(sys.stderr)
        sys.exit(1)


fail_on_unspecified(options.dispatcher_id, "DispatcherId")
fail_on_unspecified(options.command_name, "CommandName")
fail_on_unspecified(options.invocation_id, "InvocationId")
fail_on_unspecified(options.listener_id, "ListenerId")
fail_on_unspecified(options.event_handle, "EventHandle")
fail_on_unspecified(options.event_id, "EventId")
fail_on_unspecified(options.event_timestamp, "EventTimestamp")

result_msg = {
    'DispatcherId': options.dispatcher_id,
    'CommandName': options.command_name,
    'ListenerId': options.listener_id,
    'InvocationId': options.invocation_id,
    'EventId': options.event_id,
    'EventTimestamp': options.event_timestamp,
    'Message': ' '.join(args)
}

cfnbootstrap.configureLogging("DEBUG")


@util.retry_on_failure()
@util.timeout()
def send(url, data):
    requests.put(url,
                 data=json.dumps(data),
                 headers={"Content-Type": ""},
                 verify=True,
                 proxies=util.get_proxyinfo(options),
                 timeout=util.REQUEST_TIMEOUT).raise_for_status()


try:
    send(options.event_handle, result_msg)
    print('Command Event with id {} sent successfully.'.format(options.event_id))
    sys.exit(0)
except IOError as e:
    print('Error sending Command Event: {}'.format(str(e)), file=sys.stderr)
    sys.exit(1)