#!/usr/bin/python
#
# Copyright 2021 HiveMQ GmbH
#
#_________________________________________________ MOD KLL 12.8.2022
#_________________________________________________ rev 2 13.8.2022 make JSON
#_________________________________________________ rev 3 emulate a smart PowerSupply what
#_________________________________________________ sends AC V A W and get remote DC Volt setpoint and On Off
#_________________________________________________ rev 3.1 doc style, timer 

AC_Volt = 233.5 #_________________________________ Power Supply setting
DC_Volt = 15.0 #__________________________________ == MQTT node red dashboard setpoint 0 .. 15
DC_OHM = 1.0

DC_Amp = 0.0  #___________________________________ = DC Volt / DC OHM * ( 0 || 1 ) PS On Off
DC_Watt = 0.0 #___________________________________ = DC Volt * DC Amp 
PS_eff = 1.15 #___________________________________ for back calculation AC 
PS_run = 1.0  #___________________________________ == or 0.0 from MQTT node red dashboard
AC_Watt = 0.0 #___________________________________ = DC Watt * 1.15 ( about PS_efficiency ) 
AC_Amp = 0.0  #___________________________________ = AC Watt / AC Volt

count = 0 #_______________________________________ dynamic content counter

DEBUG = False #___________________________________ print and use 10 sec reporting
repsec = 60.0 #0 #____________________________________ report ever 10 min AC V A W via KLL/rpi2/getvals
replast = 0.0
#_________________________________________________ and listen to MQTT KLL/rpi2/setvals : dashboard setpoints OnOff and DC Volt changes


import time
import json
import sys, getopt
import paho.mqtt.client as paho
client = paho.Client()
from paho import mqtt

import credentials #______________________________ pack connection data at external file

#_________________________________________________ setting callbacks for different events to see if it works, print the message etc.
def on_connect(client, userdata, flags, rc, properties=None):
    print("CONNACK received with code %s." % rc)

def on_disconnect(client, userdata,rc=0):
    print("DisConnected result code "+str(rc))
    client.loop_stop()
    
#_________________________________________________ with this callback you can see if your publish was successful
def on_publish(client, userdata, mid, properties=None):
    print("send: " + str(mid))

#_________________________________________________ print which topic was subscribed to
def on_subscribe(client, userdata, mid, granted_qos, properties=None):
    print("Subscribed: " + str(mid) + " " + str(granted_qos))

#_________________________________________________ print message, useful for checking if it was successful
def on_message(client, userdata, msg):
    global DC_Volt, PS_run
    print(msg.topic + " " + str(msg.qos) + " " + str(msg.payload))    
    #_____________________________________________ KLL/RPI2/setvals 1 b'{"userVolt": 7 }'
    #_____________________________________________ KLL/RPI2/setvals 1 b'{"userPower":0}'
    setvals = json.loads(msg.payload) # string to JSON
    if ( b'"userVolt"' in msg.payload ): DC_Volt = setvals["userVolt"] # JSON to PYTHON or key error
    if ( b'"userPower"' in msg.payload ): PS_run = setvals["userPower"]
    if DEBUG: print(DC_Volt, PS_run)

def calcPS(): #___________________________________ electric simulation calc backwards from DC Volt to AC consumption
    global count
    global DC_Volt, DC_OHM, DC_Amp, DC_Watt, AC_Volt, AC_Amp, AC_Watt, PS_eff, PS_run
    DC_Amp = DC_Volt * PS_run / DC_OHM
    DC_Watt = DC_Volt * DC_Amp
    AC_Watt = DC_Watt * PS_eff
    AC_Amp = AC_Watt / AC_Volt
    #if DEBUG: print( PS_run, DC_Volt, DC_Amp, DC_Watt, AC_Volt, AC_Amp, AC_Watt )
    mJSON  = "{ \"rec\":"+str(count)
    mJSON += ",\"power\":{"
    mJSON += "\"Volt\":"+"{:.2f}".format(AC_Volt)
    mJSON += ",\"Amp\":"+"{:.2f}".format(AC_Amp)
    mJSON += ",\"Watt\":"+"{:.2f}".format(AC_Watt)
    mJSON += " } }"
    if DEBUG:
        print("__send_"+mJSON ) #_________ print full mqtt send payload
    else:
        print(count) #____________________ or just the counter,  disable if not like
        pass
        
    return mJSON
    
def send(): #_____________________________________ timer check & MQTT send
    global count, repsec, replast, DEBUG
    nowsec = time.time() #________________________ float as seconds, where 0 = epoch is January 1, 1970, 00:00:00 (UTC)
    if ( nowsec - repsec > replast ): #___________ timer end send MQTT
        mJSON = calcPS()
        client.publish(credentials.mtopic, payload=mJSON, qos=1)
        count+=1
        replast = nowsec #________________________ remember that sendtime

    #print('loop',nowsec,repsec,replast)
    client.loop(.1) #_____________________________ allow mqtt in...
    time.sleep(1.0) #_____________________________ 1 sec check, now very responsive

def cmdlinecheck(argv):
    global DEBUG
    try:
        opts, args = getopt.getopt(argv,"hvi:o:",["ifile=","ofile="])
    except getopt.GetoptError:
        print('<this>.py -v -h')
        sys.exit(2)
    for opt, arg in opts:
        if opt == '-h':
            print('commandline option: <this>.py -v')
            sys.exit()
        if opt == '-v':
            DEBUG = True 
            print('enable print and fast reporting')
        
          
def main(argv):
    global count, repsec, replast, client, DEBUG
    cmdlinecheck(argv)
    
    client = paho.Client(client_id="", userdata=None, protocol=paho.MQTTv311) # MQTT version 5, for 3.1.1: MQTTv311, 3.1: MQTTv31
    client.on_connect = on_connect
    client.on_disconnect = on_disconnect

    client.tls_set(tls_version=mqtt.client.ssl.PROTOCOL_TLS) #____________ enable TLS for secure connection
    client.username_pw_set(credentials.mqtt_user,credentials.mqtt_pwd) #__ set username and password
    client.connect(credentials.clusterURL, 8883) #________________________ connect to HiveMQ Cloud on port 8883 (default for MQTT)

    #_____________________________________________________________________ setting callbacks, use separate functions like above for better visibility
    client.on_subscribe = on_subscribe
    client.on_message = on_message
    #client.on_publish = on_publish

    client.subscribe(credentials.stopic, qos=1) #_________________________ subscribe to remote commands

    #client.publish("KLL/RPI2/getvals", payload="my_data", qos=1) #_______ a single publish, this can also  be done in loops, etc.
    #_____________________________________________________________________ loop_forever for simplicity, here you need to stop the loop manually
    #client.loop_forever()
    #client.loop_start()
    #client.loop_stop()

    #repsec = 60.0
    if DEBUG: repsec = 10.0
    print("repsec",repsec)

    while True:
        send()
    #_________________________________________________ use [ctrl][c]

if __name__ == "__main__":
    main(sys.argv[1:])