#!/usr/bin/python
# -*- coding: utf-8 -*-
import time
import serial, sys
import os
from datetime import datetime
from bitstring import BitArray


serial_timeout=0.1
byte3=0
byte4=0
byte5=0
byte6=0
i=0

pvfaultdesc = [0]*8
pvfaultdesc[0]="load short-circuit protection"
pvfaultdesc[1]="load overcurrent protection"
pvfaultdesc[2]="battery low-voltage protection"
pvfaultdesc[3]="reserved"
pvfaultdesc[4]="solar panel array1 open-circuit breakdown(it means the controller does not detect the solar panel voltage within 24h)"
pvfaultdesc[5]="solar panel array1 over-voltage protection"
pvfaultdesc[6]="delayed protection phase for load overcurrent"
pvfaultdesc[7]="shut the load compulsively"




def pv_reset_lowvoltage():
    print("Reset Unterspannungs Sicherung:")
    ser = serial.Serial('/dev/ttyUSB0', 9600, timeout=serial_timeout)
    command = "\x01\x51\x00\x00\x00\x00\x39"
    global byte3
    global byte4
    ser.flushInput() #clear buffer
    ser.write(command) #send prepared command
    ser.close()
    print("DONE")



def pv_reset_shortcuircuit():
    print("Reset Kurzschluss Sicherung:")
    ser = serial.Serial('/dev/ttyUSB0', 9600, timeout=serial_timeout)
    command = "\x01\x53\x00\x00\x00\x00\xAE"
    global byte3
    global byte4
    ser.flushInput() #clear buffer
    ser.write(command) #send prepared command
    ser.close()
    print("DONE")

def pv_reset_overcurrent():
    print("Reset Ueberlast Sicherung:")
    ser = serial.Serial('/dev/ttyUSB0', 9600, timeout=serial_timeout)
    command = "\x01\x52\x00\x00\x00\x00\x7D"
    global byte3
    global byte4
    ser.flushInput() #clear buffer
    ser.write(command) #send prepared command
    ser.close()
    print("DONE")   



def pvstatusbit(bit):
    if bit == '1':
        print("gesetzt :%s" % bit)
    else:
        print("nicht gesetzt :%s" % bit)

def pvstatus():
# current status of system
    ser = serial.Serial('/dev/ttyUSB0', 9600, timeout=serial_timeout)
    command = "\x01\x61\x00\x00\x00\x00\xBD"
    global byte3
    global byte4
    ser.flushInput() #clear buffer
    ser.write(command) #send prepared command
    skip=ser.read(2) #skip first two bytes
    byte3=ser.read(1)
    byte4=ser.read(1)
    ser.close()

    if (
            len(byte3) > 0  and len(byte4) > 0
        ):  
            byte3=byte3.encode('hex')
            bitstring1=BitArray(hex=byte3)
#            sys.stdout.write('Inputstring:\t')
#            sys.stdout.write(bitstring1.bin)
#            sys.stdout.write('\n')
            pvfaultstate(bitstring1.bin)
            sys.stdout.write('\n')
    else :
            sys.stdout.write('Voltage communication error!')

def pvfaultstate(bytearray):
    global pvfaultdesc
#    print("Inputstring Funktion:\t %s" %bytearray)
    i=0
    arraylen=len(bytearray)
#    print (" Array ist %s Elemente lang" %(arraylen))
    while i <=arraylen-1:
	if bytearray[i] =='1':
            print("Fehler aktiv: %s (Byte: %s)" % (pvfaultdesc[i], i) )
        #pvstatusbit(bytearray[i])
        if i<=arraylen: i=i+1



while True:
  try:
    now = datetime.now()
    
    os.system('clear')
    print(now)
    print("aktive Fehler:")
    pvstatus()
    time.sleep(0.5)
    #pv_reset_shortcuircuit()
    #time.sleep(0.5)
    pv_reset_overcurrent()
    time.sleep(0.5)
    pv_reset_lowvoltage()
    print("aktive Fehler nach reset:")
    pvstatus()
    print("erneuter reset nach 5 Sekunden")
# sleep 10 seconds before starting over
    time.sleep(5)


  except KeyboardInterrupt:
      print("\n\nkilled via CTRL+C -  Bye")
      #pvswitch(0) #last ausschalten


      sys.exit()