#!/usr/bin/python3
# -*- coding: UTF8 -*-

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.

"""
Display data from MQTT broker on ePaper screen

@author: arofarn
"""
__version__ = 0.2

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

from cameteo_conf import *
import paho.mqtt.client as mqtt
import time
import json
import netifaces, socket
import epd2in13
from PIL import Image
from PIL import ImageDraw
from PIL import ImageFont

mqtt_client_id = "epaper_display"

# Colors codes
white = 255
black = 0

def update_epd():
    """
    Update ePaper Display
    """
    # 90° rotation + 180° if parameter epd_rotate different of 0
    # The small translation corrects an offset after rotation of 270°
    screen = image.rotate(90 + (epd_rotate * 180),
                          expand=True,
                          translate=(-6*epd_rotate, 0))
    # Put the picture to display in frame memory and display the new frame
    epd.set_frame_memory(screen, 0, 0)
    epd.display_frame()

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

def on_connect(client, userdata, flags, rc):
    """On connection callback : topics subscription"""
    print(mqtt.connack_string(rc))
    if rc == 0:
        print("Subscribing to %s ..." % mqtt_topic)
        client.subscribe([(mqtt_topic, 0),
                          (camera_mqtt_topic + "/#", 0)]
                        )
        print("OK")


def on_message(client, userdata, msg):
    """Callback for managing data sent by MQTT broker"""

    top=msg.topic[len(mqtt_topic)-1:].strip()
    #List of the subtopics
    subtopics = top.split("/")

    #Display atmospheric data from BME280 sensor
    if subtopics[0] == "BME":
        payload = msg.payload.decode()
        val = json.loads(payload)

        #Is value consistent ?
        try:
            val['value'] = float(val['value'] )
        except:
            print("Value error: {}".format(val['value']))
            val['value'] = float('nan')

        #Manage special character "degree"
        val['unit'] = val['unit'].replace('deg', '°')

        #List of 'displayable' data types and their coordinate on screen
        coord_type = { 'AT'     : (12, 50),
                       'RH'     : (137, 50),
                       'AP'     : (12, 72),
                       'ALTI'   : (137, 72),
                      }
        print(val)
        if val['type'] in coord_type:
            #Erase old data
            draw.rectangle(coord_type[val['type']] + (coord_type[val['type']][0] + 112, coord_type[val['type']][1] + 20), fill=white)
            #Draw new values
            draw.text(coord_type[val['type']],
                      "{:6.1f}{}  ".format(val['value'], val['unit']),
                      font=font20_bold,
                      fill=black)
            update_epd()

    # Print feather's date and time on epaper display
    elif subtopics[0] == "SYS":
        payload = msg.payload.decode()
        val = json.loads(payload)
        if val['type'] == "TIME":
            try:
                #Check the date and time and offset to the right timezone
                dt_texte = datetime.strftime(datetime.strptime(val['value'], "%Y/%m/%d_%H:%M:%S") + TimeZone.utcoffset(None),
                                             "%d/%m/%Y %H:%M:%S")
            except:
                dt_texte = payload
            print(dt_texte)
            # First erase old text
            draw.rectangle((0, 34, epd2in13.EPD_HEIGHT, 48), fill=white)
            # and draw the new date
            draw.text((0, 34), dt_texte, font=font14, fill=black)

            update_epd()

def on_message_camera(client, userdata, msg):
    """Update display with info from camera (camera shooting new picture or name
    of the last photo)"""

    pl = msg.payload.decode()
    print("{} : {} ({})".format(msg.topic, pl, type(pl)))

    # If a picture is been taken
    if pl == "1" and msg.topic == camera_mqtt_topic + "/shooting" :
        draw.rectangle((0, 106, epd2in13.EPD_HEIGHT, epd2in13.EPD_WIDTH), fill=white)
        draw.text((0, 106), "Shooting photo...              ", font=font14, fill=black)
        update_epd()

    #Last picture name (with date/time)
    if msg.topic == camera_mqtt_topic + "/last_photo":
        draw.rectangle((0, 106, epd2in13.EPD_HEIGHT, epd2in13.EPD_WIDTH), fill=white)
        draw.text((0, 106), "Last: " + pl, font=font14, fill=black)
        update_epd()


def on_disconnect(client, userdata, msg):
    """Disconnection callback"""
    if msg != 0:
        print("Unexpected disconnection : {}".format(msg))
    exit()

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

#Screen init.
epd = epd2in13.EPD()
epd.init(epd.lut_full_update)

#List of TrueType fonts
font12 =        ImageFont.truetype(epd_font_file, 12)
font14 =        ImageFont.truetype(epd_font_file, 14)
font16 =        ImageFont.truetype(epd_font_file, 16)
font20 =        ImageFont.truetype(epd_font_file, 20)
font12_bold =   ImageFont.truetype(epd_bold_font_file, 12)
font14_bold =   ImageFont.truetype(epd_bold_font_file, 14)
font16_bold =   ImageFont.truetype(epd_bold_font_file, 16)
font20_bold =   ImageFont.truetype(epd_bold_font_file, 20)
#font12_obl =    ImageFont.truetype(epd_italic_font_file, 12)
#font14_obl =    ImageFont.truetype(epd_italic_font_file, 14)
#font16_obl =    ImageFont.truetype(epd_italic_font_file, 16)

#New image buffer
# Memo : 0=black, 255= white/blank
image = Image.new('1', (epd2in13.EPD_HEIGHT, epd2in13.EPD_WIDTH), 255)
draw = ImageDraw.Draw(image)

#Draw title in white on black
draw.rectangle((0, 0, epd2in13.EPD_HEIGHT, 18), fill=black)
draw.text((60, 1),
          "Projet Camétéo",
          font=font16_bold,
          fill=white)
#Write hostname and IP address
draw.text((0, 19),
          "{} : IP= {}".format(socket.gethostname(),
                               netifaces.ifaddresses('wlan0')[2][0]['addr']),
          font = font12,
          fill=black )
# Draw the black lines for data table
draw.line((0,49,epd2in13.EPD_HEIGHT, 49), fill=black)
draw.line((0,71,epd2in13.EPD_HEIGHT, 71), fill=black)
draw.line((0,93,epd2in13.EPD_HEIGHT, 93), fill=black)
draw.line((125, 49, 125, 93), fill=black)

#Display on ePaper screen
epd.clear_frame_memory(0xFF)
update_epd()

#Toggle to partial refresh
epd.init(epd.lut_partial_update)

#Connect to MQTT broker and loop...
mqtt_client = mqtt.Client(mqtt_client_id, clean_session=True)
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
#Special callback for camera
mqtt_client.message_callback_add(camera_mqtt_topic + "/#", on_message_camera)

print(mqtt_host + ":" + str(mqtt_port))
mqtt_client.connect(mqtt_host, int(mqtt_port), 60)

mqtt_client.loop_forever()