import serial
import time
import sys
import datetime

CMD_ERROR = 1
CMD_ONLINE_VALUES = 2
CMD_DATETIME = 6
CMD_SERIAL_NUMBER = 8
CMD_FIRMWARE = 9


debug = False
if len(sys.argv) > 1:
    debug_flag = sys.argv[1]
    if debug_flag == "debug":
        debug = True

s = serial.Serial(
    port='/dev/ttyUSB0',
    baudrate=9600,
    parity=serial.PARITY_NONE,
    bytesize=serial.EIGHTBITS,
    stopbits=serial.STOPBITS_ONE,
    timeout=5
)

def get_data(address, command, block):
    checksum = address + command + block
    request = [0, address, command, block, checksum]
    s.write(bytearray(request))
    s.flush()

    if debug:
        print("Sending request: {0}".format(request))

    needed_bytes = 13
    if command == 8:
        needed_bytes = 24
    answer = s.read_until(size=needed_bytes)
    if debug:
        print("Answer received: {0}".format(answer))
        pretty_print(answer)

    return answer

def pretty_print(answer):
    output = [int(x) for x in answer]
    print("Pretty: {0} len={1}".format(output,len(output)))

def validate_checksum(answer, command):
    length = len(answer)
    if command == 8:
        length = 13
    sum = 0
    for i in range(0, length-1):
        sum += answer[i]
    given_checksum = answer[length-1]
    calculated_checksum = sum % 256

    if debug:
        print("Given checksum: {0}, Calculcated checksum: {1}".format(given_checksum, calculated_checksum))

    return given_checksum == calculated_checksum

def parseOnlineValues(answer1):
    answer = [chr(x) for x in answer1]

    udc = ord(answer[0]) * 2.8 +100
    idc = ord(answer[1]) * 0.08
    uac = ord(answer[2]) + 100.0
    iac = ord(answer[3]) * 0.120
    t = ord(answer[4]) - 40.0
    s = ord(answer[5]) * 6.0
    pdc = int(udc * idc) / 1000
    pac = int(uac * iac) / 1000
    wd = (ord(answer[6]) * 256 + ord(answer[7])) / 1000
    wtot = ord(answer[8]) * 256 + ord(answer[9])
    values = {"udc":udc, "idc":idc, "uac":uac, "iac":iac, "t":t, "s":s, "pdc":pdc, "pac":pac, "wd":wd, "wtot":wtot}

def getOnlineValues(address):
    answer = get_data(address, CMD_ONLINE_VALUES, 1)
    if validate_checksum(answer, CMD_ONLINE_VALUES):
        return parseOnlineValues(answer)
    return []

def parseSerialNumber(answer1):
    answer = [chr(x) for x in answer1]
    return "".join(answer[:-2])

def getSerialNumber(address):
    answer = get_data(address, CMD_SERIAL_NUMBER, 1)
    if validate_checksum(answer, CMD_SERIAL_NUMBER):
        return parseSerialNumber(answer)
    return []

def parseFirmware(answer1):
    answer = [chr(x) for x in answer1]
    return "".join(answer[:-2])

def getFirmware(address):
    answer = get_data(address, CMD_FIRMWARE, 1)
    if validate_checksum(answer, CMD_FIRMWARE):
        return parseFirmware(answer)
    return []

def parseDateTime(answer1):
    answer = [ord(chr(x)) for x in answer1]
    date = datetime.datetime(2000 + answer[0], answer[1], answer[2], answer[3], answer[4], 0, 0)
    return date

def getDateTime(address):
    answer = get_data(address, CMD_DATETIME, 1)
    if validate_checksum(answer, CMD_DATETIME):
        return parseDateTime(answer)
    return []

def parseError(answer1):
    answer = [int(x) for x in answer1]
    #return "".join(answer[:-2])
    return answer

def getError(address):
    answer = get_data(address, CMD_ERROR, 1)
    if validate_checksum(answer, CMD_ERROR):
        return parseError(answer)
    return []

for address in range(1,2):
    print("Data for inverter at address {0}.".format(address))
    print("Serialnumber: {0}".format(getSerialNumber(address)))
    print("Firmware: {0}".format(getFirmware(address)))
#    print("Error: {0}".format(getError(address)))
#    print("DateTime: {0}".format(getDateTime(address)))
#    print("Online Values: {0}".format(getOnlineValues(address)))