# Copyright 2020 Google LLC
#
# 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
#
#     https://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 datetime
import functools
import time

from geoip import geolite2
import astral
import astral.sun
import dateutil.tz
import flask
import requests
import prometheus_flask_exporter  # type: ignore

app = flask.Flask(__name__)
_ = prometheus_flask_exporter.PrometheusMetrics(app)


def _to_sec(dt):
    return dt.hour * 60 * 60 + dt.minute * 60 + dt.second


@functools.lru_cache(maxsize=5)
def _external_ip():
    r = requests.get('https://api.ipify.org?format=json')
    return r.json().get('ip')


@app.route('/now')
def now():
    ip = flask.request.args.get('ip')
    if not ip:
        ip = flask.request.remote_addr
        if ip.startswith('192.168.') or ip.startswith('10.') or ip.startswith(
                '127.0.'):
            ip = _external_ip()
    loc = geolite2.lookup(ip)
    if loc is None:
        flask.abort(
            400,
            'LOOKUP_FAILURE: unable to resolve the location of IP address %r' %
            ip)
    tz = dateutil.tz.gettz(loc.timezone)
    epoch = time.time()
    now = datetime.datetime.now(tz)
    city = astral.LocationInfo((loc.ip, loc.country, loc.location[0],
                                loc.location[1], loc.timezone, 0))
    sun = astral.sun.sun(city.observer, date=now)
    dawn = sun['dawn']
    dusk = sun['dusk']

    resp = dict(ip=loc.ip,
                country=loc.country,
                latitude=loc.location[0],
                longitude=loc.location[1],
                timezone=loc.timezone,
                dawn=dawn,
                dawn_sec=_to_sec(dawn),
                dusk=dusk,
                dusk_sec=_to_sec(dusk),
                local_time=now,
                day_sec=_to_sec(now),
                posix_sec=int(epoch))
    return flask.jsonify(resp)