# GCoder.py: basic geocoding test

import sys
import argparse
import json
import configparser
import urllib.parse
import urllib.request


class GeocodingError(RuntimeError):
    pass


def geocode_google(config, address):
    apikey = config['google']['apikey']
    if not apikey:
        raise GeocodingError("Google API key not specified")
    query = { 'key': apikey, 'address': address, 'region': 'us'}
    url = 'https://maps.googleapis.com/maps/api/geocode/json?' + \
          urllib.parse.urlencode(query, quote_via=urllib.parse.quote)
    with urllib.request.urlopen(url) as response:
        if response.status == 200:
            apireturn = json.loads(response.read())
            stat = apireturn['status']
            if stat == 'OK':
                results = apireturn['results']
                if len(results) > 1:
                    raise GeocodingError(f"Google API returned ambiguous results (total count {len(results)})")
                coords = results[0]['geometry']['location']
                return coords['lat'], coords['lng']
            else:
                raise GeocodingError(f"Google API returns status of {stat}")
        else:
            raise GeocodingError(f"Google API returns {response.status} HTTP status code")


def geocode_mapquest(config, address):
    apikey = config['mapquest']['apikey']
    if not apikey:
        raise GeocodingError("MapQuest API key not specified")
    query = { 'key': apikey, 'inFormat': 'kvp', 'outFormat': 'json', 'location': address,
              'thumbMaps': 'false', 'maxResults': 1}
    url = 'https://www.mapquestapi.com/geocoding/v1/address?' + urllib.parse.urlencode(query)
    with urllib.request.urlopen(url) as response:
        if response.status == 200:
            apireturn = json.loads(response.read())
            stat = apireturn['info']['statuscode']
            if stat == 0:
                results = apireturn['results']
                if len(results) > 1:
                    raise GeocodingError(f"MapQuest API returned ambiguous results (total count {len(results)})")
                locations = results[0]['locations']
                if len(locations) > 1:
                    raise GeocodingError(f"MapQuest API returned ambiguous locations (total count {len(locations)})")
                coords = locations[0]['latLng']
                return coords['lat'], coords['lng']
            else:
                raise GeocodingError(f"MapQuest API returns status of {stat}")
        else:
            raise GeocodingError(f"MapQuest API returns {response.status} HTTP status code")


def geocode_geocodio(config, address):
    apikey = config['geocodio']['apikey']
    if not apikey:
        raise GeocodingError("Geocodio API key not specified")
    query = {'q': address, 'api_key': apikey}
    url = 'https://api.geocod.io/v1.6/geocode?' + urllib.parse.urlencode(query)
    with urllib.request.urlopen(url) as response:
        if response.status == 200:
            apireturn = json.loads(response.read())
            coords = apireturn['results'][0]['location']
            return coords['lat'], coords['lng']
        else:
            raise GeocodingError(f"Geocodio API returns {response.status} HTTP status code")


def geocode_locationiq(config, address):
    apikey = config['locationiq']['token']
    if not apikey:
        raise GeocodingError("LocationIQ API key not specified")
    query = {'q': address, 'key': apikey, 'format': 'json', 'limit': 1}
    url = 'https://us1.locationiq.com/v1/search.php?' + urllib.parse.urlencode(query, quote_via=urllib.parse.quote)
    with urllib.request.urlopen(url) as response:
        if response.status == 200:
            apireturn = json.loads(response.read())
            place = apireturn[0]
            return place['lat'], place['lon']
        else:
            raise GeocodingError(f"LocationIQ API returns {response.status} HTTP status code")


geocoding_procs = {
    'google':     geocode_google,
    'mapquest':   geocode_mapquest,
    'geocodio':   geocode_geocodio,
    'locationiq': geocode_locationiq
}

cmdline_parser = argparse.ArgumentParser()
cmdline_parser.add_argument('address', nargs='+', help='The address to be geocoded')
cmdline_parser.add_argument('-C', '--config', default='geoapi.ini', help='The geocoding API configuration file')
cmdline_parser.add_argument('-g', '--geocoder', default='google', choices=geocoding_procs.keys(),
                            help='Geocoding processor to use to get coordinates (default: google)')


def main(args):
    opts = cmdline_parser.parse_args(args)
    config = configparser.ConfigParser()
    config.read(opts.config)
    my_address = ' '.join(opts.address)
    print(f"Address: '{my_address}'")
    coords = geocoding_procs[opts.geocoder](config, my_address)
    print(f"Coordinates: Latitude {coords[0]}, longitude {coords[1]}")


if __name__ == '__main__':
    sys.exit(main(sys.argv[1:]))