import smbus
import struct
import time

def read_voltage(bus):
    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 read_capacity(bus):
    address = 0x36
    read = bus.read_word_data(address, 0X04)
    swapped = struct.unpack("<H", struct.pack(">H", read))[0]
    capacity = swapped / 256
    return capacity

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

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

bus = smbus.SMBus(1)
power_on_reset(bus)
quick_start(bus)
previous_voltage = read_voltage(bus)

while True:
    print("++++++++++++++++++++")
    current_voltage = read_voltage(bus)
    print("Battery:%4i%% %5.2fV" % (read_capacity(bus), current_voltage))
    if current_voltage > previous_voltage:
        print("     Charging")
    elif current_voltage < previous_voltage:
        print("    Discharging")
    previous_voltage = current_voltage
    capacity = read_capacity(bus)
    if capacity >= 99:
        print("----Battery FULL----")
    elif capacity <= 15 and capacity > 5:
        print("----Battery LOW-----")
    elif capacity <= 5:
        print("  D A N G E R !!!")
        print("BATT. CRITICAL LEVEL")
    print("++++++++++++++++++++")
    time.sleep(5)