#!/usr/bin/env python
import struct
import smbus
import sys
import time
import RPi.GPIO as GPIO

def readVoltage(bus):
	
	"This function returns as float the voltage from the Raspi UPS Hat via the provided SMBus object"
	address = 0x36
	read = bus.read_word_data(address, 0X02)
	swapped = struct.unpack("<H", struct.pack(">H", read))[0]
	voltage = swapped * 1.25 /1000/16
	return voltage

def readCapacity(bus):
	
	"This function returns as a float the remaining capacity of the battery connected to the Raspi UPS Hat via the provided SMBus object"
	address = 0x36
	read = bus.read_word_data(address, 0X04)
	swapped = struct.unpack("<H", struct.pack(">H", read))[0]
	capacity = swapped/256
	return capacity

def QuickStart(bus):
	address = 0x36
	bus.write_word_data(address, 0x06,0x4000)

def PowerOnReset(bus):
	address = 0x36
	bus.write_word_data(address, 0xfe,0x0054)

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
GPIO.setup(4,GPIO.IN)

bus = smbus.SMBus(1) # 0 = /dev/i2c-0 (port I2C0), 1 = /dev/i2c-1 (port I2C1)

PowerOnReset(bus)
QuickStart(bus)

print (" ")
print "Initialize the MAX17040 ......"

while True:

print "++++++++++++++++++++"
print "Voltage:%5.2fV" % readVoltage(bus)
print "Battery:%5i%%" % readCapacity(bus)

if readCapacity(bus) == 100:
	print "Battery FULL"

if readCapacity(bus) < 5:
	print "Battery LOW"

if (GPIO.input(4) == GPIO.HIGH):
	print "Power Adapter Plug In "

if (GPIO.input(4) == GPIO.LOW):
	print "Power Adapter Unplug"

print "++++++++++++++++++++"
time.sleep(2)