#!/usr/bin/python2
# -*- coding: utf8 -*-

# Get data from MQTT broker and print them to 
# Papirus ePaper display

from papirus import Papirus
from papirus import PapirusTextPos

import paho.mqtt.client as mqtt

import datetime
import decimal

# MQTT settings
mqtt_server =   'localhost'
mqtt_port=      1883
mqtt_auth=      {'username':'cameteo',
                 'password':'CaMeteo'}
mqtt_client_id= 'mqtt2papirus'

topic="pi/papirus_zero_hat/temperature/#"

# Papirus display settings
disp_rotation = 0
font_path = '/usr/share/fonts/truetype/freefont/FreeMono.ttf'
font_path_bold = '/usr/share/fonts/truetype/freefont/FreeMonoBold.ttf'
text_size = 15

date = datetime.datetime.now().replace(microsecond=0).isoformat()
temp = "-"
unit_temp = "\u00B0C"

#Set the dispaly and position of text
text = PapirusTextPos(False, rotation=disp_rotation)
#text.Clear()
text.AddText(date, 0, 0, text_size, Id="Date", font_path=font_path_bold)
text.AddText("Connecting to MQTT...", 5, 15,  text_size, Id="Temperature", font_path=font_path)
text.WriteAll()

# The callback for when the client receives a CONNACK response from the server.
def on_connect(client, userdata, flags, rc):
    print("Connected with result code "+str(rc))
    date = datetime.datetime.now().replace(microsecond=0).isoformat()
    text.UpdateText("Date", date, font_path=font_path_bold)
    text.UpdateText("Temperature", "Connected to MQTT !")
    text.WriteAll()
    # Subscribing in on_connect() means that if we lose the connection and
    # reconnect then subscriptions will be renewed.
    client.unsubscribe("$SYS/#")
    client.subscribe(topic)

# The callback for when a PUBLISH message is received from the server.
def on_message(client, userdata, msg):
    global unit_temp
    top=msg.topic[len(topic)-1:].strip()
    print(top+" : "+str(msg.payload))
    
    if top == "date" :
        text.UpdateText("Date", msg.payload, font_path=font_path_bold)
    
    if top == "unit" :
        unit_temp = msg.payload
    
    if top == "value" :
        val = decimal.Decimal(msg.payload)
        txt = "T= %.1f" % val + unit_temp.decode("utf-8")
        text.UpdateText("Temperature", txt)
        text.WriteAll()

########
# Main #
########

#Connect to MQTT broker and loop...
mqtt_client = mqtt.Client(mqtt_client_id, clean_session=False)
mqtt_client.username_pw_set(mqtt_auth['username'], mqtt_auth['password'])
mqtt_client.on_connect = on_connect
mqtt_client.on_message = on_message
mqtt_client.connect(mqtt_server, mqtt_port, 60)

mqtt_client.loop_forever()