#!/usr/bin/env python3

"""
This script does the following:
 * gets temperature and humidity from two connected DHT22 sensors
 * gets the energy gain of a PV system via an intermediate Tasmota smart plug
 * sends an APRS message containing the gathered information to APRS-IS
"""

import requests
import aprslib
import Adafruit_DHT

TASMOTA_IP = "192.168.1.100" # change to IP address of Tasmota device
DHT_SENSOR = Adafruit_DHT.DHT22
SENSOR_RACK = 27 # change to corresponding GIO Pin
SENSOR_OUTSIDE = 17 # change to corresponding GIO Pin
APRS_SYMBOL = "-" # pick your APRS symbol here
CALL = "XXXXX-15" # enter your call sign
PASSWORD = "12345" # generate a passcode for your call and enter it here
PORT = 14580 # should be okay
GPS_COORDINATES = "585.36N/04041.46W" # enter your coordinates here


def get_energy_data():
    """grabs data from the Tasmota smart plug via HTTP request"""
    resp = requests.get(url="http://{}/cm?cmnd=STATUS+8".format(TASMOTA_IP))
    data = resp.json()
    energy = data["StatusSNS"]["ENERGY"]
    # Balkonkraftwerke (certain small PV systems) only generate 600W...
    if energy["Power"] > 600:
        energy["Power"] = 600
    energy["Total"] = str(format(energy["Total"], '.1f'))
    energy["Yesterday"] = str(format(energy["Yesterday"], '.1f'))
    energy["Today"] = str(format(energy["Today"], '.1f'))
    return energy


def send_aprs(weather_data, energy_data):
    """sends the APRS message to APRS-IS"""
    # a valid passcode for the callsign is required in order to send
    ais = aprslib.IS(CALL, passwd=PASSWORD, port=PORT)
    ais.connect()
    # send a single status message
    msg = "PV Power:{} W, Today:{} kWh, Yesterday:{} kWh, Total:{} kWh - {}".format(\
           energy_data["Power"], energy_data["Today"], energy_data["Yesterday"], \
           energy_data["Total"], weather_data)
    print(msg)
    ais.sendall("{}>APRS,TCPIP*:={}{} {}".format(CALL, GPS_COORDINATES, APRS_SYMBOL, msg))
    ais.sendall("{}>APRS,TCPIP*:>".format(CALL))


def get_weather_data():
    """grabs temperature and humidity from the attached DHT22 sensors"""
    humidity_rack, temperature_rack = Adafruit_DHT.read_retry(DHT_SENSOR, SENSOR_RACK)
    humidity_outside, temperature_outside = Adafruit_DHT.read_retry(DHT_SENSOR, SENSOR_OUTSIDE)
    ret_val = "WX: "
    if humidity_rack is not None and temperature_rack is not None:
        ret_val = ret_val + "Rack:{0:0.1f}C/{1:0.1f}%".format(\
                temperature_rack, humidity_rack)
    else:
        print("Failed to retrieve data from rack sensor")
    if humidity_outside is not None and temperature_outside is not None:
        ret_val = ret_val + " Outside:{0:0.1f}C/{1:0.1f}%".format(\
                temperature_outside, humidity_outside)
    else:
        print("Failed to retrieve data from outside sensor")
    return ret_val


if __name__ == "__main__":
    send_aprs(get_weather_data(), get_energy_data())