# Pérenisation de données arrivant sur un MQTT
# vers une base de données MariaDb/MySQL
# Auteur : Arofarn
# v0.2

#################
# Configuration #
#################

###########
# IMPORTS #
###########

from cameteo import *
import paho.mqtt.client as mqtt
import json
from math import isnan

mqtt_client_id = "sql_persistance"

#############
# CALLBACKS #
#############

#Callback pour la connection au MQTT : souscriptions aux topics
def on_connect(client, userdata, flags, rc):
    print(mqtt.connack_string(rc))
    if rc == 0:
        print("Subscribing to %s ..." % mqtt_topic)
        client.subscribe([(mqtt_topic, 0),
                          (camera_mqtt_topic + "/last_photo", 0)
                         ])
        print("OK")
    

#Callback de gestion des messages arrivant au MQTT :
#  affichage et enregistrement en base de données
def on_message(client, userdata, msg):
    top=msg.topic[len(mqtt_topic)-1:].strip()

    subtopics = top.split("/")
    payload = msg.payload.decode()
    #print(payload)
    val = json.loads(payload)
        
    #Test présence et cohérence de la valeur        
    try:
        val['value'] = float(val['value'] )
    except:
        print("Value error: {}".format(val['value']))
        val['value'] = float('nan')
    
    #Remplacement de la valeur en cas de nullité
    if isnan(val['value']) or val['value'] == -99.9:
        val['value'] = 'NULL'
    
    #Gestion du symbole des degrés parfois difficile pour certaines sources
    val['unit'] = val['unit'].replace('deg', '°')
    
    #print("%s : %s %s (%s)" % (val['type'], val['value'], val['unit'], subtopics[0]))
    
    #Enregistrement des données en base    
    data= Data(valdate = datetime.strptime(val['date'], "%H:%M:%S %d/%m/%Y"),
               dbdate  = datetime.now(),
               value   = val['value'],
               unit    = val['unit'],
               type_id = val['type'],
               sensor_id = subtopics[0] )
    
    print(data)
    
    try:
        db.session.add(data)
        db.session.commit()
    except:
        print("Erreur lors de l'enregistrement en base de données")
    finally:
        db.session.close()
        
#Callback particulier pour gérer les date/heure arrivent sur le broker MQTT
def on_message_date(client, userdata, msg):
    payload = msg.payload.decode()
    try:
        d = datetime.strptime(payload, "%H:%M:%S %d/%m/%Y")
        print("Date : %s" % d)
    except:
        print("Date mal formatée : %s" % payload)

#Update display with info from camera (camera shooting new photo or name of the
# last photo)
def on_message_camera(client, userdata, msg):
    pl = msg.payload.decode()    
    print("New photo : " + pl)
    
    # New photo to add to database
    photo = Photo(file_name = pl,
                  file_date = datetime.strptime(os.path.splitext(pl)[0], photo_name),
                  image_type = photo_format)
    try:
        db.session.add(photo)
        db.session.commit()
    except:
        print("Erreur lors de l'enregistrement en base de données")
    finally:
        db.session.close()
        
#Callback de déconnexion au broker MQTT
def on_disconnect(client, userdata, msg):
    if msg != 0:
        print("Déconnexion imprévu : %s" % msg)
    exit()
    
########
# Main #
########

#Connect to MQTT broker and loop...
mqtt_client = mqtt.Client(mqtt_client_id, clean_session=False)
mqtt_client.username_pw_set(mqtt_user, mqtt_pass)
mqtt_client.on_connect = on_connect
mqtt_client.on_message = on_message
mqtt_client.on_disconnect = on_disconnect

mqtt_client.message_callback_add(camera_mqtt_topic + "/last_photo", on_message_camera)
mqtt_client.message_callback_add("huzzah0/NTP/date", on_message_date)
    
mqtt_client.connect(mqtt_host, int(mqtt_port), 60)

mqtt_client.loop_forever()