ogn-python/ogn/utils.py

import requests
import csv
from io import StringIO

from .model import Device, AddressOrigin

from geopy.geocoders import Nominatim

DDB_URL = "http://ddb.glidernet.org/download"


address_prefixes = {'F': 'FLR',
                    'O': 'OGN',
                    'I': 'ICA'}


def get_ddb(csvfile=None):
    if csvfile is None:
        r = requests.get(DDB_URL)
        rows = '\n'.join(i for i in r.text.splitlines() if i[0] != '#')
        address_origin = AddressOrigin.ogn_ddb
    else:
        r = open(csvfile, 'r')
        rows = ''.join(i for i in r.readlines() if i[0] != '#')
        address_origin = AddressOrigin.user_defined

    data = csv.reader(StringIO(rows), quotechar="'", quoting=csv.QUOTE_ALL)

    devices = list()
    for row in data:
        flarm = Device()
        flarm.address_type = row[0]
        flarm.address = row[1]
        flarm.aircraft = row[2]
        flarm.registration = row[3]
        flarm.competition = row[4]
        flarm.tracked = row[5] == 'Y'
        flarm.identified = row[6] == 'Y'

        flarm.address_origin = address_origin

        devices.append(flarm)

    return devices


def get_trackable(ddb):
    l = []
    for i in ddb:
        if i.tracked and i.address_type in address_prefixes:
            l.append('{}{}'.format(address_prefixes[i.address_type], i.address))
    return l


def get_country_code(latitude, longitude):
    geolocator = Nominatim()
    location = geolocator.reverse("%f, %f" % (latitude, longitude))
    try:
        country_code = location.raw["address"]["country_code"]
    except KeyError:
        country_code = None
    return country_code


def wgs84_to_sphere(receiver_beacon, aircraft_beacon):
    from math import pi, asin, sqrt, sin, cos, atan2
    deg2rad = pi / 180
    rad2deg = 180 / pi

    lat1 = receiver_beacon.latitude * deg2rad
    lon1 = receiver_beacon.longitude * deg2rad
    alt1 = receiver_beacon.altitude

    lat2 = aircraft_beacon.latitude * deg2rad
    lon2 = aircraft_beacon.longitude * deg2rad
    alt2 = aircraft_beacon.altitude

    distance = 6366000 * 2 * asin(sqrt((sin((lat1 - lat2) / 2))**2 + cos(lat1) * cos(lat2) * (sin((lon1 - lon2) / 2))**2))
    theta = atan2(alt2 - alt1, distance) * rad2deg
    phi = atan2(sin(lon1 - lon2) * cos(lat2), cos(lat1) * sin(lat2) - sin(lat1) * cos(lat2) * cos(lon1 - lon2)) * rad2deg

    radius = sqrt(distance**2 + (alt2 - alt1)**2)
    return radius, theta, phi