#!/usr/bin/env python3

# SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
# SPDX-License-Identifier: Apache-2.0

from __future__ import absolute_import

import argparse
import json
import logging
import netaddr
import re
import ssl
import urllib.parse
import urllib.request
from ruamel import yaml

# create shared logger
logging.basicConfig()
logger = logging.getLogger("nbht")

# headers to pass, set globally
headers = []

# settings
settings = {}

def parse_nb_args():
    """
    parse CLI arguments
    """

    parser = argparse.ArgumentParser(description="NetBox Host Descriptions")

    # Positional args
    parser.add_argument(
        "settings",
        type=argparse.FileType("r"),
        help="YAML ansible inventory file w/netbox info",
    )

    parser.add_argument(
        "--debug", action="store_true", help="Print additional debugging information"
    )

    return parser.parse_args()


def json_api_get(
    url,
    headers,
    data=None,
    trim_prefix=False,
    allow_failure=False,
    validate_certs=False,
):
    """
    Call JSON API endpoint, return data as a dict
    """

    logger.debug("json_api_get url: %s", url)

    # if data included, encode it as JSON
    if data:
        data_enc = str(json.dumps(data)).encode("utf-8")

        request = urllib.request.Request(url, data=data_enc, method="POST")
        request.add_header("Content-Type", "application/json; charset=UTF-8")
    else:
        request = urllib.request.Request(url)

    # add headers tuples
    for header in headers:
        request.add_header(*header)

    try:

        if validate_certs:
            response = urllib.request.urlopen(request)

        else:
            ctx = ssl.create_default_context()
            ctx.check_hostname = False
            ctx.verify_mode = ssl.CERT_NONE

            response = urllib.request.urlopen(request, context=ctx)

    except urllib.error.HTTPError:
        # asking for data that doesn't exist results in a 404, just return nothing
        if allow_failure:
            return None
        logger.exception("Server encountered an HTTPError at URL: '%s'", url)
    except urllib.error.URLError:
        logger.exception("An URLError occurred at URL: '%s'", url)
    else:
        # docs: https://docs.python.org/3/library/json.html
        jsondata = response.read()
        logger.debug("API response: %s", jsondata)

    try:
        data = json.loads(jsondata)
    except json.decoder.JSONDecodeError:
        # allow return of no data
        if allow_failure:
            return None
        logger.exception("Unable to decode JSON")
    else:
        logger.debug("JSON decoded: %s", data)

    return data


def get_pxe_devices(tenant_group, filters=""):

    # get all devices in a prefix
    url = "%s%s" % (
        settings["api_endpoint"],
        "api/dcim/devices/?tenant_group=%s%s" % (tenant_group, filters),
    )

    print(url)

    raw_devs = json_api_get(url, headers, validate_certs=settings["validate_certs"])

    logger.debug("raw_devs: %s", raw_devs)

    devs = []

    for item in raw_devs["results"]:
        dev = {}
        dev["serial"] = item["serial"]
        dev["hostname"] = item["name"]
        dev["domain"] = "aetherproject.net"

        devs.append(dev)

    return devs


# main function that calls other functions
if __name__ == "__main__":

    args = parse_nb_args()

    # only print log messages if debugging
    if args.debug:
        logger.setLevel(logging.DEBUG)
    else:
        logger.setLevel(logging.INFO)

    # load settings from yaml file
    settings = yaml.safe_load(args.settings.read())

    logger.info("settings: %s" % settings)

    # global, so this isn't run multiple times
    headers = [
        ("Authorization", "Token %s" % settings["token"]),
    ]

    # create structure from extracted data

    pxe_devices = get_pxe_devices("aether", "&role_id=1")

    print(yaml.safe_dump({"pxeboot_hosts": pxe_devices}, indent=2))