#!/usr/bin/env python
# -*- coding: utf-8 -*-
# __author__ = "Sébastien Reuiller"
# __licence__ = "Apache License 2.0"

# Python 3, prérequis : pip install pySerial influxdb
# TIC Enedis référence : Enedis-NOI-CPT_54E.pdf
# https://www.enedis.fr/media/2035/download

import logging
import time
from datetime import datetime

import requests
import serial
from influxdb import InfluxDBClient

import settings as cfg

# clés à utiliser - les autres ne seront pas transmises
USED_MESURE_KEYS = [
    'LTARF',
    'EAST',
    'EASF01',
    'EASF02',
    'IRMS1',
    'URMS1',
    'SINSTS',
    'SMAXSN',
    'CCASN',
    'UMOY1',
    'MSG1',
    'NTARF',
]

# clés téléinfo
INT_MESURE_KEYS = [
    'EAST',
    'EASF',
    'EASD',
    'EAIT',
    'ERQ',
    'IRMS',
    'URMS',
    'PREF',
    'PCOUP',
    'SINST',
    'SMAX',
    'CCA',
    'UMOY',
]

# création du logguer
logging.basicConfig(filename=cfg.LOGFILE, level=logging.INFO, format='%(asctime)s %(message)s')
logging.info("Teleinfo starting..")

# connexion a la base de données InfluxDB
if cfg.influxdb["PASSWORD"]:
    client = InfluxDBClient(host=cfg.influxdb["HOST"], port=cfg.influxdb["PORT"], username=cfg.influxdb["USER"], password=cfg.influxdb["PASSWORD"])
else:
    client = InfluxDBClient(host=cfg.influxdb["HOST"], port=cfg.influxdb["PORT"], username=cfg.influxdb["USER"])

connected = False
while not connected:
    try:
        logging.info("Database %s exists?" % cfg.influxdb["DB_NAME"])
        if not {'name': cfg.influxdb["DB_NAME"]} in client.get_list_database():
            logging.info("Database %s creation.." % cfg.influxdb["DB_NAME"])
            client.create_database(cfg.influxdb["DB_NAME"])
            logging.info("Database %s created!" % cfg.influxdb["DB_NAME"])
        client.switch_database(cfg.influxdb["DB_NAME"])
        logging.info("Connected to %s!" % cfg.influxdb["DB_NAME"])
    except requests.exceptions.ConnectionError:
        logging.info('InfluxDB is not reachable. Waiting 5 seconds to retry.')
        time.sleep(5)
    else:
        connected = True


def add_measures(measures):
    points = []
    for measure, values in measures.items():
        point = {
            "measurement": measure,
            "tags": {
                # identification de la sonde et du compteur
                "host": "raspberry",
                "region": "linky"
            },
            "time": datetime.utcnow().strftime("%Y-%m-%dT%H:%M:%SZ"),
            "fields": values
        }
        points.append(point)
    client.write_points(points)


def verif_checksum(data, checksum):
    data_unicode = 0
    for caractere in data:
        data_unicode += ord(caractere)
    sum_unicode = (data_unicode & 63) + 32
    return (checksum == chr(sum_unicode))

def checksum(line:str) -> str:
    return chr((sum(list(line)) & 0x3F) + 0x20)

def main():
    with serial.Serial(port=cfg.SERIAL, baudrate=9600, parity=serial.PARITY_EVEN, bytesize=serial.SEVENBITS, timeout=1) as ser:

        logging.info("Teleinfo is reading on %s.." % cfg.SERIAL)
        trame = dict()

        # boucle pour partir sur un début de trame
        line = ser.readline()
        while b'\x02' not in line:  # recherche du caractère de début de trame
            line = ser.readline()

        delaycounter = cfg.SKIPPED_TRAMES
        while True:
            line = ser.readline()
            logging.debug(line)
            try:
                dataset = line.replace(b'\x03\x02', b'').rstrip(b'\r\n')
                checksumchar = checksum(dataset[:-1])
                if checksumchar == chr(dataset[-1]):
                    spline = dataset.split(b'\t')
                    logging.debug(spline)
                    etiquette = spline[0].decode('ascii')
                    if etiquette in USED_MESURE_KEYS:
                        value = spline[1].decode('ascii')
                        timestamp = None
                        if len(spline) == 4 and spline[2] != b'' : # Horodaté
                            value = spline[2].decode('ascii')
                            timestamp = spline[1].decode('ascii')
                        for radix in INT_MESURE_KEYS:
                            if etiquette.startswith(radix):
                                value = int(value)
                        trame[etiquette] = {
                            "value": value,
                            "timestamp": timestamp,
                        }
                else:
                    logging.debug('Checksum error, aborting frame')
                if b'\x03' in line:  # si caractère de fin dans la ligne, on insère la trame dans influx
                    if delaycounter >= cfg.SKIPPED_TRAMES:
                        time_measure = time.time()

                        # insertion dans influxdb
                        add_measures(trame)
                        # ajout timestamp pour debugger
                        trame["timestamp"] = int(time_measure)
                        logging.debug(trame)
                        delaycounter = 0
                    else:
                        delaycounter += 1

                    trame = dict()  # on repart sur une nouvelle trame
            except Exception as e:
                logging.error("Exception : %s" % e, exc_info=True)
                logging.error("%s" % (line))


if __name__ == '__main__':
    if connected:
        main()