elodie.geolocation

Complexity

Total Complexity

106

Size/Duplication

Total Lines	405
Duplicated Lines	0 %

Importance

Changes

0

12 Functions

Rating	Name	Duplication	Size	Complexity
A	dms_to_decimal()	0	8	2
A	dms_string()	0	8	5
A	decimal_to_dms()	0	8	2
D	coordinates_by_name()	0	44	12
A	parse_result()	0	18	5
A	get_key()	0	15	4
C	parse_result_address()	0	40	9
B	parse_result_latlon()	0	12	6
A	get_prefer_english_names()	0	18	5
F	exiftool_geolocation()	0	93	29
F	place_name()	0	53	15
D	lookup()	0	43	12

"""Look up geolocation information for media objects."""
from __future__ import print_function
from __future__ import division
from future import standard_library
from past.utils import old_div

standard_library.install_aliases()  # noqa

from os import path

import requests
import urllib.request
import urllib.parse
import urllib.error

from elodie.config import load_config
from elodie import constants
from elodie import log
from elodie.localstorage import Db
from elodie.external.pyexiftool import ExifTool

__KEY__ = None
__DEFAULT_LOCATION__ = 'Unknown Location'
__PREFER_ENGLISH_NAMES__ = None


def coordinates_by_name(name):
    # Try to get cached location first
    db = Db()
    cached_coordinates = db.get_location_coordinates(name)
    if(cached_coordinates is not None):
        return {
            'latitude': cached_coordinates[0],
            'longitude': cached_coordinates[1]
        }

    # If the name is not cached then we go ahead with an API lookup
    geolocation_info = lookup(location=name)

    if(geolocation_info is not None):
        if(
            'results' in geolocation_info and
            len(geolocation_info['results']) != 0 and
            'locations' in geolocation_info['results'][0] and
            len(geolocation_info['results'][0]['locations']) != 0
        ):

            # By default we use the first entry unless we find one with
            #   geocodeQuality=city.
            geolocation_result = geolocation_info['results'][0]
            use_location = geolocation_result['locations'][0]['latLng']
            # Loop over the locations to see if we come accross a
            #   geocodeQuality=city.
            # If we find a city we set that to the use_location and break
            for location in geolocation_result['locations']:
                if(
                    'latLng' in location and
                    'lat' in location['latLng'] and
                    'lng' in location['latLng'] and
                    location['geocodeQuality'].lower() == 'city'
                ):
                    use_location = location['latLng']
                    break

            return {
                'latitude': use_location['lat'],
                'longitude': use_location['lng']
            }

    return None


def decimal_to_dms(decimal):
    decimal = float(decimal)
    decimal_abs = abs(decimal)
    minutes, seconds = divmod(decimal_abs*3600, 60)
    degrees, minutes = divmod(minutes, 60)
    degrees = degrees
    sign = 1 if decimal >= 0 else -1
    return (degrees, minutes, seconds, sign)


def dms_to_decimal(degrees, minutes, seconds, direction=' '):
    sign = 1
    if(direction[0] in 'WSws'):
        sign = -1
    return (
        float(degrees) + old_div(float(minutes), 60) +
        old_div(float(seconds), 3600)
    ) * sign


def dms_string(decimal, type='latitude'):
    # Example string -> 38 deg 14' 27.82" S
    dms = decimal_to_dms(decimal)
    if type == 'latitude':
        direction = 'N' if decimal >= 0 else 'S'
    elif type == 'longitude':
        direction = 'E' if decimal >= 0 else 'W'
    return '{} deg {}\' {}" {}'.format(dms[0], dms[1], dms[2], direction)

The variable direction does not seem to be defined for all execution paths.

def get_key():
    global __KEY__
    if __KEY__ is not None:
        return __KEY__

    if constants.mapquest_key is not None:
        __KEY__ = constants.mapquest_key
        return __KEY__

    config = load_config()
    if('MapQuest' not in config):
        return None

    __KEY__ = config['MapQuest']['key']
    return __KEY__

def get_prefer_english_names():
    global __PREFER_ENGLISH_NAMES__
    if __PREFER_ENGLISH_NAMES__ is not None:
        return __PREFER_ENGLISH_NAMES__

    config_file = '%s/config.ini' % constants.application_directory
    if not path.exists(config_file):
        return False

    config = load_config()
    if('MapQuest' not in config):
        return False

    if('prefer_english_names' not in config['MapQuest']):
        return False

    __PREFER_ENGLISH_NAMES__ = bool(config['MapQuest']['prefer_english_names'])
    return __PREFER_ENGLISH_NAMES__

def exiftool_geolocation(lat, lon):
    """Use ExifTool's geolocation database to look up place name from coordinates.
    
    :param float lat: Latitude coordinate
    :param float lon: Longitude coordinate
    :returns: dict with location information or None if not found
    """
    if lat is None or lon is None:
        return None
    
    # Convert lat/lon to floats
    if not isinstance(lat, float):
        lat = float(lat)
    if not isinstance(lon, float):
        lon = float(lon)
    
    try:
        with ExifTool() as et:
            # Query the geolocation database directly using -listgeo and find nearest match
            # Format: City,Region,Subregion,CountryCode,Country,TimeZone,FeatureCode,Population,Latitude,Longitude
            geo_data = et.execute(b"-listgeo", b"-csv").decode('utf-8')
            
            if not geo_data:
                return None
            
            lines = geo_data.strip().split('\n')
            if len(lines) < 2:  # Header + at least one data line
                return None
            
            # Skip header line
            best_match = None
            min_distance = float('inf')
            
            for line in lines[1:]:  # Skip header
                try:
                    parts = line.split(',')
                    if len(parts) >= 10 and parts[8] != 'Latitude':  # Skip header if it appears again
                        city = parts[0]
                        region = parts[1] 
                        subregion = parts[2]
                        country_code = parts[3]
                        country = parts[4]
                        db_lat = float(parts[8])
                        db_lon = float(parts[9])
                        
                        # Calculate simple distance (not exact but good enough for nearest city)
                        distance = ((lat - db_lat) ** 2 + (lon - db_lon) ** 2) ** 0.5
                        
                        if distance < min_distance:
                            min_distance = distance
                            best_match = {
                                'city': city,
                                'region': region,
                                'subregion': subregion,
                                'country': country,
                                'country_code': country_code
                            }
                            
                            # If we found a very close match (within ~0.1 degrees), use it
                            if distance < 0.1:
                                break
                                
                except (ValueError, IndexError):
                    continue
            
            if best_match and min_distance < 2.0:  # Within reasonable distance
                lookup_place_name = {}
                
                # Priority order: City > Region > Subregion > Country
                if best_match['city'] and best_match['city'].strip():
                    lookup_place_name['city'] = best_match['city']
                    lookup_place_name['default'] = best_match['city']
                elif best_match['region'] and best_match['region'].strip():
                    lookup_place_name['state'] = best_match['region']
                    if 'default' not in lookup_place_name:
                        lookup_place_name['default'] = best_match['region']
                elif best_match['subregion'] and best_match['subregion'].strip():
                    lookup_place_name['state'] = best_match['subregion']
                    if 'default' not in lookup_place_name:
                        lookup_place_name['default'] = best_match['subregion']
                
                if best_match['country'] and best_match['country'].strip():
                    lookup_place_name['country'] = best_match['country']
                    if 'default' not in lookup_place_name:
                        lookup_place_name['default'] = best_match['country']
                
                return lookup_place_name if lookup_place_name else None
                
    except Exception as e:
        log.error("ExifTool geolocation failed: {}".format(e))
        return None
    
    return None


def place_name(lat, lon):
    lookup_place_name_default = {'default': __DEFAULT_LOCATION__}
    if(lat is None or lon is None):
        return lookup_place_name_default

    # Convert lat/lon to floats
    if(not isinstance(lat, float)):
        lat = float(lat)
    if(not isinstance(lon, float)):
        lon = float(lon)

    # Try to get cached location first
    db = Db()
    # 3km distace radious for a match
    cached_place_name = db.get_location_name(lat, lon, 3000)
    # We check that it's a dict to coerce an upgrade of the location
    #  db from a string location to a dictionary. See gh-160.
    if(isinstance(cached_place_name, dict)):
        return cached_place_name

    lookup_place_name = {}
    
    # Check if MapQuest key is configured
    key = get_key()
    if key is not None:
        # Use MapQuest if key is available
        geolocation_info = lookup(lat=lat, lon=lon)
        if(geolocation_info is not None and 'address' in geolocation_info):
            address = geolocation_info['address']
            # gh-386 adds support for town
            # taking precedence after city for backwards compatability
            for loc in ['city', 'town', 'state', 'country']:
                if(loc in address):
                    lookup_place_name[loc] = address[loc]
                    # In many cases the desired key is not available so we
                    #  set the most specific as the default.
                    if('default' not in lookup_place_name):
                        lookup_place_name['default'] = address[loc]
    else:
        # Use ExifTool geolocation if no MapQuest key is configured
        lookup_place_name = exiftool_geolocation(lat, lon)
        if not lookup_place_name:
            lookup_place_name = {}

    if(lookup_place_name):
        db.add_location(lat, lon, lookup_place_name)
        # TODO: Maybe this should only be done on exit and not for every write.
        db.update_location_db()

    if('default' not in lookup_place_name):
        lookup_place_name = lookup_place_name_default

    return lookup_place_name


def lookup(**kwargs):
    if(
        'location' not in kwargs and
        'lat' not in kwargs and
        'lon' not in kwargs
    ):
        return None

    if('lat' in kwargs and 'lon' in kwargs):
        kwargs['location'] = '{},{}'.format(kwargs['lat'], kwargs['lon'])

    key = get_key()
    prefer_english_names = get_prefer_english_names()

    if(key is None):
        return None

    try:
        headers = {}
        params = {'format': 'json', 'key': key}
        if(prefer_english_names):
            headers = {'Accept-Language':'en-EN,en;q=0.8'}
            params['locale'] = 'en_US'
        params.update(kwargs)
        path = '/geocoding/v1/address'
        if('lat' in kwargs and 'lon' in kwargs):
            path = '/geocoding/v1/reverse'
        url = '%s%s?%s' % (
                    constants.mapquest_base_url,
                    path,
                    urllib.parse.urlencode(params)
              )
        # log the MapQuest url gh-446
        log.info('MapQuest url: %s' % (url))
        r = requests.get(url, headers=headers)
        return parse_result(r.json())
    except requests.exceptions.RequestException as e:
        log.error(e)
        return None
    except ValueError as e:
        log.error(r.text)
        log.error(e)
        return None


def parse_result(result):
    # gh-421
    # Return None if statusCode is not 0
    #   https://developer.mapquest.com/documentation/geocoding-api/status-codes/
    if( 'info' not in result or
        'statuscode' not in result['info'] or
        result['info']['statuscode'] != 0
       ):
        return None

    address = parse_result_address(result)
    if(address is None):
        return None

    result['address'] = address
    result['latLng'] = parse_result_latlon(result)

    return result

def parse_result_address(result):
    # We want to store the city, state and country
    # The only way determined to identify an unfound address is 
    #   that none of the indicies were found
    if( 'results' not in result or
        len(result['results']) == 0 or
        'locations' not in result['results'][0] or
        len(result['results'][0]['locations']) == 0
        ):
        return None

    index_found = False
    addresses = {'city': None, 'state': None, 'country': None}
    result_compat = {}
    result_compat['address'] = {}


    locations = result['results'][0]['locations'][0]
    # We are looping over locations to find the adminAreaNType key which
    #   has a value of City, State or Country.
    # Once we find it then we obtain the value from the key adminAreaN
    #   where N is a numeric index.
    # For example
    #   * adminArea1Type = 'City'
    #   * adminArea1 = 'Sunnyvale'
    for key in locations:
        # Check if the key is of the form adminArea1Type
        if(key[-4:] == 'Type'):
            # If it's a type then check if it corresponds to one we are intereated in
            #   and store the index by parsing the key
            key_prefix = key[:-4]
            key_index = key[-5:-4]
            if(locations[key].lower() in addresses):
                addresses[locations[key].lower()] = locations[key_prefix]
                index_found = True

    if(index_found is False):
        return None

    return addresses

def parse_result_latlon(result):
    if( 'results' not in result or
        len(result['results']) == 0 or
        'locations' not in result['results'][0] or
        len(result['results'][0]['locations']) == 0 or
        'latLng' not in result['results'][0]['locations'][0]
        ):
        return None

    latLng = result['results'][0]['locations'][0]['latLng'];

    return {'lat': latLng['lat'], 'lon': latLng['lng']}