#!/usr/bin/env python3

# Send lora packet to node-red when being triggered by postgresql
# Nico Schottelius <nico.schottelius -at- ungleich.ch>
# 2016-11-02
# GPLv3+



import binascii
import lorautil

#              L A T I T U D E        L O N G I TU DE
# status temp  deg min sec +hem   deg min  min  min
# 9e       17  46  58  204  0       009 02 320  a5 9a   0e e7
# 1        2   3   4   5   6       ?  8   9  10  11 12   13 14


# on display: 46 58 122N   09 02 207E
#             46.58 204    09.02 320
# sodaq: lat=46.9699219 lon=9.0391764
# google:    46.969943,     9.038999

known_devices = [ "0018B20000000C58", "0018B20000000C37", "0018B20000000C59", "0018B20000000CD0" ]


def get_gps(deveui, payload):
    res = []
    if not int(payload[0:2], 16) & (2**7):
        return res

    lat_deg = float(payload[4:6])
    lat_min = float(payload[6:8])
    lat_sec = float(payload[8:10])
    lat_frac_sec = float(payload[10:11])
    lat = lat_deg + lat_min/60.0 + lat_sec/3600.0 + lat_frac_sec/36000.0

    long_deg = float(payload[12:15])
    long_min = float(payload[15:17])
    long_sec = float(payload[17:19])
    long_frac_sec = float(payload[19:20])
    long = long_deg + long_min/60.0 + long_sec/3600 + long_frac_sec/36000.0

    pos = ":lat={:.6f} long={:.6f}".format(lat, long)

    res = [ deveui + pos ]

    return res

def get_temp(deveui, payload):
    res = []

    if int(payload[0:2], 16) & (2**7):
        res = [ deveui + ":temperature=" + str(binascii.a2b_hex(payload)[1])]

    return res

def decode_adeunis(pkg):
    data = pkg.split(":")

    deveui = data[0]
    payload = data[1]

    res = []

    # Only handle known devices
    if not deveui in known_devices:
        return res

    res += get_temp(deveui, payload)
    res += get_gps(deveui, payload)

    return res

def nodered_adeunisrf(provider, data):
    res = decode_adeunis(data)
    if not res:
        return

    with websocket.create_connection("ws://localhost:1880/{}".format(provider)) as ws:
        for d in res:
            ws.send("%s" % d)


if __name__ == '__main__':
    conns = lorautil.pg_conn_notify()

    while True:
        lorautil.pg_wait_for_pkg(conns, nodered_adeunisrf)