plugin.py

###
# Copyright (c) 2018-2022, James Lu <james@overdrivenetworks.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:
#
#   * Redistributions of source code must retain the above copyright notice,
#     this list of conditions, and the following disclaimer.
#   * 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.
#   * Neither the name of the author of this software nor the name of
#     contributors to this software may be used to endorse or promote products
#     derived from this software without specific prior written consent.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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
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# POSSIBILITY OF SUCH DAMAGE.
###
import json
import os
import string
import urllib.error

from supybot import utils, plugins, ircutils, callbacks, world, conf, log
from supybot.commands import *
try:
    from supybot.i18n import PluginInternationalization
    _ = PluginInternationalization('NuWeather')
except ImportError:
    # Placeholder that allows to run the plugin on a bot
    # without the i18n module
    _ = lambda x: x

from .config import BACKENDS, GEOCODE_BACKENDS
from .config import DEFAULT_FORMAT, DEFAULT_FORECAST_FORMAT, DEFAULT_FORMAT_CURRENTONLY
from .local import accountsdb
from . import formatter, request_cache as cache


HEADERS = {
    'User-agent': 'Mozilla/5.0 (compatible; Supybot/Limnoria %s; NuWeather weather plugin)' % conf.version
}

class NuWeather(callbacks.Plugin):
    """Weather plugin for Limnoria"""
    threaded = True

    def __init__(self, irc):
        super().__init__(irc)
        # We use 2 DBs: one to store preferred locations and another for location latlon (geocoding)
        self.db = accountsdb.AccountsDB("NuWeather", 'NuWeather.db', self.registryValue(accountsdb.CONFIG_OPTION_NAME))
        geocode_db_filename = conf.supybot.directories.data.dirize("NuWeather-geocode.json")
        if os.path.exists(geocode_db_filename):
            with open(geocode_db_filename, encoding='utf-8') as f:
                self.geocode_db = json.load(f)
        else:
            self.log.info("NuWeather: Creating new geocode DB")
            self.geocode_db = {}
        world.flushers.append(self.db.flush)
        world.flushers.append(self._flush_geocode_db)

        self._last_channel = None

    def _flush_geocode_db(self):
        geocode_db_filename = conf.supybot.directories.data.dirize("NuWeather-geocode.json")
        with open(geocode_db_filename, 'w', encoding='utf-8') as f:
            json.dump(self.geocode_db, f)

    def die(self):
        world.flushers.remove(self.db.flush)
        world.flushers.remove(self._flush_geocode_db)
        self.db.flush()
        self._flush_geocode_db()
        super().die()

    @staticmethod
    def _fetch_json(url, get_error=None):
        try:
            data = utils.web.getUrl(url, headers=HEADERS).decode('utf-8')
        except utils.web.Error as e:
            log.debug('NuWeather: error fetching %s', url, exc_info=True)
            backend = utils.web.urlparse(url).netloc
            reason = f'{e} from {backend}'
            if isinstance(e.__cause__, urllib.error.HTTPError):
                # When receiving an HTTP error, try reading and showing the API response anyways
                # This requires a Limnoria version > 2021-08-01
                data = e.__cause__.read().decode("utf-8")
                json_response = json.loads(data, strict=False)
                if get_error:
                    if extended_reason := get_error(json_response):
                        reason = f'{reason} - {extended_reason}'
            raise callbacks.Error(reason)
        return json.loads(data, strict=False)

    def _nominatim_geocode(self, location):
        location = location.lower()

        url = 'https://nominatim.openstreetmap.org/search?q=%s&format=jsonv2' % utils.web.urlquote(location)
        self.log.debug('NuWeather: using url %s (geocoding)', url)
        # Custom User agent & caching are required for Nominatim per https://operations.osmfoundation.org/policies/nominatim/
        data = self._fetch_json(url)
        if not data:
            raise callbacks.Error("Unknown location %r from OSM/Nominatim" % location)

        data = data[0]
        # Limit location verbosity to 3 divisions (e.g. City, Province/State, Country)
        display_name = data['display_name']
        display_name_parts = display_name.split(', ')
        if len(display_name_parts) > 3:
            if display_name_parts[-2].isdigit():  # Try to remove ZIP code-like divisions
                display_name_parts.pop(-2)
            display_name = ', '.join([display_name_parts[0]] + display_name_parts[-2:])

        lat = float(data['lat'])
        lon = float(data['lon'])
        osm_id = data.get('osm_id')
        self.log.debug('NuWeather: saving %s,%s (osm_id %s, %s) for location %s from OSM/Nominatim', lat, lon, osm_id, display_name, location)

        result = (lat, lon, display_name, osm_id, "OSM/Nominatim")
        return result

    def _googlemaps_geocode(self, location):
        location = location.lower()
        apikey = self.registryValue('apikeys.googlemaps')
        if not apikey:
            raise callbacks.Error("No Google Maps API key.")

        url = "https://maps.googleapis.com/maps/api/geocode/json?address={0}&key={1}".format(utils.web.urlquote(location), apikey)
        self.log.debug('NuWeather: using url %s (geocoding)', url)

        data = self._fetch_json(url)
        if data['status'] != "OK":
            raise callbacks.Error("{0} from Google Maps for location {1}".format(data['status'], location))

        data = data['results'][0]
        lat = data['geometry']['location']['lat']
        lon = data['geometry']['location']['lng']
        display_name = data['formatted_address']
        place_id = data['place_id']

        self.log.debug('NuWeather: saving %s,%s (place_id %s, %s) for location %s from Google Maps', lat, lon, place_id, display_name, location)
        result = (lat, lon, display_name, place_id, "Google\xa0Maps")
        return result

    def _opencage_geocode(self, location):
        location = location.lower()
        apikey = self.registryValue('apikeys.opencage')
        if not apikey:
            raise callbacks.Error("No OpenCage API key.")

        url = "https://api.opencagedata.com/geocode/v1/json?q={0}&key={1}&abbrv=1&limit=1".format(utils.web.urlquote(location), apikey)
        self.log.debug('NuWeather: using url %s (geocoding)', url)

        data = self._fetch_json(url)
        if data['status']['message'] != "OK":
            raise callbacks.Error("{0} from OpenCage for location {1}".format(data['status']['message'], location))
        elif not data['results']:
            raise callbacks.Error("Unknown location %r from OpenCage" % location)

        data = data['results'][0]
        lat = data['geometry']['lat']
        lon = data['geometry']['lng']
        display_name = data['formatted']
        place_id = data['annotations']['geohash']

        self.log.debug('NuWeather: saving %s,%s (place_id %s, %s) for location %s from OpenCage', lat, lon, place_id, display_name, location)
        result = (lat, lon, display_name, place_id, "OpenCage")
        return result

    def _weatherstack_geocode(self, location):
        location = location.lower()
        apikey = self.registryValue('apikeys.weatherstack')
        if not apikey:
            raise callbacks.Error("No weatherstack API key.")

        url = "http://api.weatherstack.com/current?access_key={0}&query={1}".format(apikey, utils.web.urlquote(location))
        self.log.debug('NuWeather: using url %s (geocoding)', url)

        data = self._fetch_json(url)
        if data.get('error'):
            raise callbacks.Error("{0} From weatherstack for location {1}".format(data['error']['info'], location))

        lat = data['location']['lat']
        lon = data['location']['lon']
        display_name = data['request']['query']
        place_id = "{0},{1}".format(lat, lon)

        self.log.debug('NuWeather: saving %s,%s (place_id %s,%s) for location %s from weatherstack', lat, lon, place_id, display_name, location)
        result = (lat, lon, display_name, place_id, "weatherstack")
        return result

    def _geocode(self, location, geobackend=None):
        geocode_backend = geobackend or self.registryValue('geocodeBackend', channel=self._last_channel)
        if geocode_backend not in GEOCODE_BACKENDS:
            raise callbacks.Error(_("Unknown geocode backend %r. Valid ones are: %s") % (geocode_backend, ', '.join(GEOCODE_BACKENDS)))

        result_pair = str((location, geocode_backend))  # escape for json purposes
        if result_pair in self.geocode_db:
            # 2022-05-24: fix Nominatim returning the wrong type
            if not isinstance(result_pair[0], float):
                del self.geocode_db[result_pair]
            else:
                self.log.debug('NuWeather: using cached latlon %s for location %r', self.geocode_db[result_pair], location)
                return self.geocode_db[result_pair]
        elif location in self.geocode_db:
            # Old DBs from < 2019-03-14 only had one field storing location, and always
            # used OSM/Nominatim. Remove these old entries and regenerate them.
            self.log.debug('NuWeather: deleting outdated cached location %r', location)
            del self.geocode_db[location]

        backend_func = getattr(self, '_%s_geocode' % geocode_backend)
        result = backend_func(location)
        self.geocode_db[result_pair] = result  # Cache result persistently
        return result

    def _format_tmpl_temp(self, *args, **kwargs):
        displaymode = self.registryValue('units.temperature', channel=self._last_channel)
        return formatter.format_temp(displaymode, *args, **kwargs)

    def _format_tmpl_distance(self, *args, **kwargs):
        if kwargs.get('speed'):
            displaymode = self.registryValue('units.speed', channel=self._last_channel)
        else:
            displaymode = self.registryValue('units.distance', channel=self._last_channel)
        return formatter.format_distance(displaymode, *args, **kwargs)

    def _weatherstack_fetcher(self, location, geobackend=None):
        """Grabs weather data from weatherstack (formerly Apixu)."""
        apikey = self.registryValue('apikeys.weatherstack')
        if not apikey:
            raise callbacks.Error(_("Please configure the weatherstack API key in plugins.nuweather.apikeys.weatherstack . "
                                    "Apixu users please see https://github.com/apilayer/weatherstack#readme"))
        # HTTPS is not supported on free accounts. Don't ask me why
        url = 'http://api.weatherstack.com/current?' + utils.web.urlencode({
            'access_key': apikey,
            'query': location,
            'units': 'f',
        })
        self.log.debug('NuWeather: using url %s', url)

        data = self._fetch_json(url)

        currentdata = data['current']

        return {
            'location': data['request']['query'],
            'poweredby': 'weatherstack',
            'url': '',
            'current': {
                'condition': currentdata['weather_descriptions'][0],
                'temperature': self._format_tmpl_temp(f=currentdata['temperature']),
                'feels_like': self._format_tmpl_temp(f=currentdata['feelslike']),
                'humidity': formatter.format_percentage(currentdata['humidity']),
                'precip': formatter.format_precip(inches=currentdata['precip']),
                'wind': self._format_tmpl_distance(mi=currentdata['wind_speed'], speed=True),
                'wind_dir': currentdata['wind_dir'],
                'uv': formatter.format_uv(currentdata['uv_index']),
                'visibility': self._format_tmpl_distance(mi=currentdata.get('visibility')),
            }
        }

    _WWIS_CITIES_REFRESH_INTERVAL = 2592000  # 30 days
    _wwis_cities = {}
    def _wwis_load_cities(self):
        wwis_cities_cache_path = conf.supybot.directories.data.dirize("wwis-cities.json")
        if cache.check_cache_outdated(wwis_cities_cache_path, self._WWIS_CITIES_REFRESH_INTERVAL):
            # FIXME: support other languages?
            url = 'https://worldweather.wmo.int/en/json/Country_en.json'
            wwis_cities_raw = cache.get_json_save_cache(url, wwis_cities_cache_path, HEADERS)
        elif self._wwis_cities:
            # already loaded and up to date; nothing to do
            return
        else:
            wwis_cities_raw = cache.load_json_cache(wwis_cities_cache_path)

        self._wwis_cities.clear()
        # Process WWIS data to map (lat, lon) -> (cityId, cityName)
        for _membid, member_info in wwis_cities_raw['member'].items():
            if not isinstance(member_info, dict):
                continue
            for city in member_info['city']:
                lat, lon = float(city['cityLatitude']), float(city['cityLongitude'])
                self._wwis_cities[(lat, lon)] = city['cityId']

    def _wwis_get_closest_city(self, location, geobackend=None):
        # WWIS equivalent of geocode - finding the closest major city
        try:
            import haversine
        except ImportError as e:
            raise callbacks.Error("This feature requires the 'haversine' Python module - see https://pypi.org/project/haversine/") from e

        latlon = self._geocode(location, geobackend=geobackend)
        if not latlon:
            raise callbacks.Error("Unknown location %s." % location)

        lat, lon, _display_name, _geocodeid, geocode_backend = latlon
        self._wwis_load_cities()

        closest_cities = sorted(self._wwis_cities, key=lambda k: haversine.haversine((lat, lon), k))
        return self._wwis_cities[closest_cities[0]], geocode_backend

    def _wwis_get_current(self):
        # Load current conditions (wind, humidity, ...)
        # These are served from a separate endpoint with all(!) locations at once!
        wwis_current_cache_path = conf.supybot.directories.data.dirize("wwis-current.json")

        if cache.check_cache_outdated(wwis_current_cache_path, self._WWIS_CURRENT_REFRESH_INTERVAL):
            url = 'https://worldweather.wmo.int/en/json/present.json'
            return cache.get_json_save_cache(url, wwis_current_cache_path, HEADERS)
        return cache.load_json_cache(wwis_current_cache_path)

    _WWIS_CURRENT_REFRESH_INTERVAL = 300     # 5 minutes
    _wwis_current = None
    def _wwis_fetcher(self, location, geobackend=None):
        """Grabs weather data from the World Weather Information Service."""
        cityid, geocode_backend = self._wwis_get_closest_city(location, geobackend=geobackend)

        # Load forecast and city metadata (name, country, etc.)
        # I don't bother caching these because they're unique to every city
        city_url = f'https://worldweather.wmo.int/en/json/{cityid}_en.json'
        log.debug('NuWeather: fetching city info & forecasts for %r from %s', location, city_url)
        city_data = self._fetch_json(city_url)
        city_data = city_data['city']

        # Load current conditions (wind, humidity, ...)
        # These are served from a separate endpoint with all(!) locations at once!
        # The file altogether is sizable (~1MB), so I cached them to disk
        wwis_current_cache_path = conf.supybot.directories.data.dirize("wwis-current.json")
        if cache.check_cache_outdated(wwis_current_cache_path, self._WWIS_CURRENT_REFRESH_INTERVAL):
            url = 'https://worldweather.wmo.int/en/json/present.json'
            self._wwis_current = cache.get_json_save_cache(url, wwis_current_cache_path, HEADERS)
        elif not self._wwis_current:
            # First run, e.g. after reload
            self._wwis_current = cache.load_json_cache(wwis_current_cache_path)
        current_data = self._wwis_current

        display_name = f"{city_data['cityName']}, " \
                       f"{city_data['member']['shortMemName'] or city_data['member']['memName']}"

        current_data_city = None
        for current_data_city in current_data['present'].values():
            # FIXME: This is really inefficient; I have no idea why current city info isn't already
            # indexed by city ID ...
            if current_data_city['cityId'] == cityid:
                break
        if not current_data_city:
            raise ValueError(f"Could not find current conditions for cityID {cityid} ({display_name})")
        return {
            'location': display_name,
            'poweredby': 'WWIS+' + geocode_backend,
            'url': f'https://worldweather.wmo.int/en/city.html?cityId={cityid}',
            'current': {
                'condition': current_data_city["wxdesc"],
                'temperature': self._format_tmpl_temp(c=current_data_city['temp']) if current_data_city['temp'] else _("N/A"),
                'feels_like': _("N/A"),
                'humidity': formatter.format_percentage(current_data_city['rh']) if current_data_city['rh'] else _("N/A"),
                'precip': _("N/A"),
                'wind': self._format_tmpl_distance(km=float(current_data_city['ws'])*3.6, speed=True) if current_data_city['ws'] else _("N/A"),
                'wind_gust': _("N/A"),
                'wind_dir': current_data_city['wd'],
                'uv': _("N/A"),
                'visibility': _("N/A"),
            },
            'forecast': [{'dayname': formatter.get_dayname(forecastdata['forecastDate'], -1,
                                                           fallback=forecastdata['forecastDate']),
                          'max': self._format_tmpl_temp(c=int(forecastdata['maxTemp']) if forecastdata['maxTemp'] else None),
                          'min': self._format_tmpl_temp(c=int(forecastdata['minTemp']) if forecastdata['minTemp'] else None),
                          'summary': forecastdata.get('weather', 'N/A')}
                        for forecastdata in city_data['forecast']['forecastDay']]
        }

    def _pirateweather_fetcher(self, location, geobackend=None):
        """Grabs weather data from Pirate Weather."""
        apikey = self.registryValue('apikeys.pirateweather')
        if not apikey:
            raise callbacks.Error(_("Please configure the Pirate Weather API key in plugins.nuweather.apikeys.pirateweather."))

        # Convert location to lat,lon first
        latlon = self._geocode(location, geobackend=geobackend)
        if not latlon:
            raise callbacks.Error("Unknown location %s." % location)

        lat, lon, display_name, geocodeid, geocode_backend = latlon

        # We don't use minutely or hourly data; alerts are not supported
        url = 'https://api.pirateweather.net/forecast/%s/%s,%s?units=us&exclude=minutely,hourly,alerts' % (apikey, lat, lon)
        self.log.debug('NuWeather: using url %s', url)

        data = self._fetch_json(url, get_error=lambda resp: resp.get('message'))
        currentdata = data['currently']

        # N.B. Dark Sky docs tell to not expect any values to exist except the timestamp attached to the response
        return {
            'location': display_name,
            'poweredby': 'Pirate\xa0Weather+' + geocode_backend,
            'url': 'https://merrysky.net/forecast/%s,%s' % (lat, lon),
            'current': {
                'condition': currentdata.get('summary', 'N/A'),
                'temperature': self._format_tmpl_temp(f=currentdata.get('temperature')),
                'feels_like': self._format_tmpl_temp(f=currentdata.get('apparentTemperature')),
                'humidity': formatter.format_percentage(currentdata.get('humidity')),
                'precip': formatter.format_precip(mm=currentdata.get('precipIntensity')),
                'wind': self._format_tmpl_distance(mi=currentdata.get('windSpeed', 0), speed=True),
                'wind_gust': self._format_tmpl_distance(mi=currentdata.get('windGust', 0), speed=True),
                'wind_dir': formatter.wind_direction(currentdata.get('windBearing')),
                'uv': formatter.format_uv(currentdata.get('uvIndex')),
                'visibility': self._format_tmpl_distance(mi=currentdata.get('visibility')),
            },
            'forecast': [{'dayname': formatter.get_dayname(forecastdata['time'], idx, tz=data['timezone']),
                          'max': self._format_tmpl_temp(f=forecastdata.get('temperatureHigh')),
                          'min': self._format_tmpl_temp(f=forecastdata.get('temperatureLow')),
                          'summary': forecastdata.get('summary', 'N/A').rstrip('.')} for idx, forecastdata in enumerate(data['daily']['data'])]
        }

    def _openweathermap_fetcher(self, location, geobackend=None):
        """Grabs weather data from OpenWeatherMap."""
        apikey = self.registryValue('apikeys.openweathermap')
        if not apikey:
            raise callbacks.Error(_("Please configure the OpenWeatherMap API key in plugins.nuweather.apikeys.openweathermap"))

        # Convert location to lat,lon first
        latlon = self._geocode(location, geobackend=geobackend)
        if not latlon:
            raise callbacks.Error("Unknown location %s." % location)

        lat, lon, __, ___, geocode_backend = latlon
        url = 'https://api.openweathermap.org/data/2.5/weather?' + utils.web.urlencode({
            'appid': apikey,
            'lat': lat,
            'lon': lon,
            'units': 'imperial',
        })
        self.log.debug('NuWeather: using url %s (current data)', url)

        data = self._fetch_json(url, get_error=lambda resp: resp.get('message'))

        output = {
            'location': '%s, %s' % (data['name'], data['sys']['country']),
            'poweredby': 'OpenWeatherMap+' + geocode_backend,
            'url': 'https://openweathermap.org/weathermap?' + utils.web.urlencode({
                'lat': lat,
                'lon': lon,
                'zoom': 12
            }),
            # Unfortunately not all of the fields we use are available
            'current': {
                'condition': data['weather'][0]['description'],
                'temperature': self._format_tmpl_temp(f=data['main']['temp']),
                'feels_like': self._format_tmpl_temp(f=data['main']['feels_like']),
                'humidity': formatter.format_percentage(data['main']['humidity']),
                'precip': 'N/A',
                'wind': self._format_tmpl_distance(mi=data['wind']['speed'], speed=True),
                'wind_gust': 'N/A',
                'wind_dir': formatter.wind_direction(data['wind']['deg']),
                'uv': 'N/A',  # Requires a separate API call
                'visibility': self._format_tmpl_distance(km=data['visibility']/1000),
            }
        }
        tzoffset = data['timezone']

        # Get extended forecast (a separate API call)
        url = 'https://api.openweathermap.org/data/2.5/forecast?' + utils.web.urlencode({
            'appid': apikey,
            'lat': lat,
            'lon': lon,
            'units': 'imperial',
        })
        self.log.debug('NuWeather: using url %s (extended forecast)', url)
        data = self._fetch_json(url)

        # OWM's 5 day forecast gives data by 3 hour intervals. The actual daily forecast
        # requires a subscription.
        output['forecast'] = [
            {'dayname': formatter.get_dayname(forecast['dt'], -1, fallback=forecast['dt_txt']),
             'max': self._format_tmpl_temp(f=forecast['main']['temp_max']),
             'min': self._format_tmpl_temp(f=forecast['main']['temp_min']),
             'summary': forecast['weather'][0]['description']}
            # grab data every 6 hours, excluding first pocket
            for forecast in data['list'][1::2]
        ]
        return output

    def _format_weather(self, data, channel, forecast=False):
        """
        Formats and returns current conditions.
        """
        # Work around IRC length limits for config opts...
        data['c'] = data['current']
        data['f'] = data.get('forecast')

        flat_data = formatter.flatten_subdicts(data)
        if flat_data.get('url'):
            flat_data['url'] = utils.str.url(flat_data['url'])

        forecast_available = bool(data.get('forecast'))
        if forecast:  # --forecast option was given
            if forecast_available:
                fmt = self.registryValue('outputFormat.forecast', channel=channel) or DEFAULT_FORECAST_FORMAT
            else:
                raise callbacks.Error(_("Extended forecast info is not available from this backend."))
        else:
            if forecast_available:
                fmt = self.registryValue('outputFormat', channel=channel) or DEFAULT_FORMAT
            else:
                fmt = self.registryValue('outputFormat.currentOnly', channel=channel) or DEFAULT_FORMAT_CURRENTONLY
        template = string.Template(fmt)

        return template.safe_substitute(flat_data)

    @wrap([getopts({'user': 'nick', 'backend': None, 'weather-backend': None, 'geocode-backend': None, 'forecast': ''}), additional('text')])
    def weather(self, irc, msg, args, optlist, location):
        """[--user <othernick>] [--weather-backend/--backend <weather backend>] [--geocode-backend <geocode backend>] [--forecast] [<location>]

        Fetches weather and forecast information for <location>. <location> can be left blank if you have a previously set location (via 'setweather').

        If --forecast is specified, show an extended (default: 5-day) forecast for <location>.

        If the --user option is specified, show weather for the saved location of that nick, instead of the caller's.

        If either --weather-backend/--backend or --geocode-backend is specified, will override the default backends if provided backend is available.
        """
        optlist = dict(optlist)
        self._last_channel = msg.channel

        # Default to the caller
        if optlist.get('user'):
            try:
                hostmask = irc.state.nickToHostmask(optlist['user'])
            except KeyError:
                irc.error(_("I don't know who %r is.") % optlist['user'], Raise=True)
        else:
            hostmask = msg.prefix
        # Can be specified location or default one in DB
        location = location or self.db.get(hostmask)

        if not location:
            irc.error(_("I did not find a preset location for you. Please set one via 'setweather <location>'."), Raise=True)

        weather_backend = optlist.get('weather-backend') or optlist.get('backend') or self.registryValue('defaultBackend', msg.args[0])
        if weather_backend not in BACKENDS:
            irc.error(_("Unknown weather backend %s. Valid ones are: %s") % (weather_backend, ', '.join(BACKENDS)), Raise=True)
        geocode_backend = optlist.get('geocode-backend', self.registryValue('geocodeBackend', msg.args[0]))

        backend_func = getattr(self, '_%s_fetcher' % weather_backend)
        raw_data = backend_func(location, geocode_backend)

        s = self._format_weather(raw_data, msg.channel, forecast='forecast' in optlist)

        irc.reply(s)

    @wrap([getopts({'user': 'nick', 'backend': None}), 'text'])
    def geolookup(self, irc, msg, args, optlist, location):
        """[--backend <backend>] <location>

        Looks up <location> using a geocoding backend.
        """
        optlist = dict(optlist)
        self._last_channel = msg.channel
        geocode_backend = optlist.get('backend', self.registryValue('geocodeBackend', msg.args[0]))

        data = self._geocode(location, geobackend=geocode_backend)
        lat, lon, display_name, place_id, backend = data

        s = 'From %s: \x02%s\x02 [ID: %s] \x02%s,%s' % (backend, display_name, place_id, lat, lon)
        irc.reply(s)

    @wrap(['text'])
    def setweather(self, irc, msg, args, location):
        """<location>

        Saves the weather location for your bot account, or hostmask if you are not registered.
        """
        self.db.set(msg.prefix, location)
        irc.replySuccess()

    @wrap([getopts({'geocode-backend': None}), "text"])
    def aqi(self, irc, msg, args, optlist, location):
        """[--geocode-backend <backend>] <location>

        Looks up Air Quality Index information for <location> using aqicn.org.

        --geocode-backend can be set to "native" or any geocoding backend supported by the NuWeather plugin. If nothing is given, this defaults to the backend set in 'plugins.nuweather.geocodeBackend'

        --geocode-backend native refers aqicn's built-in city search, which supports basic city names as well as aqicn station IDs in the form "@1234".
        """
        apikey = self.registryValue("apiKeys.aqicn")
        if not apikey:
            irc.error("The API Key is not set. Please set it via the 'plugins.nuweather.apikeys.aqicn' config "
                      "variable. You can sign up for an API key at https://aqicn.org/api", Raise=True)

        # We can use aqicn.org's builtin search or one of NuWeather's geocoding backends
        geocode_backend = dict(optlist).get('geocode-backend')
        if geocode_backend not in {'', 'native'}:
            result = self._geocode(location, geobackend=geocode_backend)

            # Set location to geo:lat:lon, per https://aqicn.org/json-api/doc/#api-Geolocalized_Feed-GetGeolocFeed
            location = 'geo:%s;%s' % (result[0], result[1])

        url = 'https://api.waqi.info/feed/%s/?%s' % (utils.web.urlquote(location), utils.web.urlencode({'token': apikey}))
        self.log.debug('AQI: using URL %s', url)

        f = utils.web.getUrl(url)
        data = json.loads(f.decode('utf-8'))

        if data['status'] == 'error':
            irc.error('Got API error: %s' % data['data'], Raise=True)
        else:
            # AQI value: usually a number, except for when there's no data (a literal '-')
            aqino = data['data']['aqi']

            placename = data['data']['city']['name']
            infourl = data['data']['city']['url']
            attribs = [obj['name'] for obj in data['data']['attributions']]

            formatted_aqi = formatter.format_aqi(aqino)
            s = format(_('%s :: %s %u; from %L'), ircutils.bold(placename), formatted_aqi, infourl, attribs)
            irc.reply(s)

Class = NuWeather


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