from serial import Serial
from math import inf
import sys
import binascii

def crap_to_number(num, unit, acdc):
    number_str = ""

    if(num[0]&0x10):
        number_str+="-"
        num[0] &= 0xEF

    for elem in num:
        if(elem & 0x10 != 0):
            number_str+="."
        switch={
                0xcf:"9",
                0xef:"8",
                0x8a:"7",
                0xe7:"6",
                0xc7:"5",
                0x4e:"4",
                0x8f:"3",
                0xad:"2",
                0x0a:"1",
                0xeb:"0",
                0x61:"L",
                0x00:" "
                }
        number_str+=switch.get(elem&0xEF, "-")

    if (unit[0] & 0x1):
        number_str+="µ"
    if (unit[1] & 0x1):
        number_str+="m"
    if (unit[1] & 0x2):
        number_str+="%"
    if (unit[1] & 0x4):
        number_str+="M"
    if (unit[2] & 0x1):
        number_str+="F"
    if (unit[2] & 0x2):
        number_str+="Ω"
    if (unit[3] & 0x1):
        number_str+="A"
    if (unit[3] & 0x2):
        number_str+="V"
    if (unit[3] & 0x4):
        number_str+="Hz"
    if (unit[4] & 0x2):
        number_str+="°C"
    if (unit[4] & 0x1):
        number_str+="°F"

    if(acdc&0xb == 0x0a):
        number_str+=" DC"
    if(acdc&0xb == 0x09):
        number_str+=" AC"

    return number_str


def read_peaktech( ser ):

                line = ser.read_until( b'\xf1' )
                #print(binascii.hexlify(line))
                good=1
                if(len(line) == 15):
                    for i in range(0, 0xf):
                        if i+1 != ((line[i]&0xF0)>>4):
                            good=0
                else:
                    line = ser.read_until( b'\xf1' )

                bytearr = bytearray(line)

                if(good==1):
                    for i in range(0, 0xf):
                        bytearr[i] = (bytearr[i] & 0x0F)
                    #print(binascii.hexlify(bytearr))

                    acdc = bytearr[0]

                    num = []
                    num.append((bytearr[1]<<4) | bytearr[2])
                    num.append((bytearr[3]<<4) | bytearr[4])
                    num.append((bytearr[5]<<4) | bytearr[6])
                    num.append((bytearr[7]<<4) | bytearr[8])

                    unit = []
                    unit.append(bytearr[9] )
                    unit.append(bytearr[10])
                    unit.append(bytearr[11])
                    unit.append(bytearr[12])
                    unit.append(bytearr[13])

                    #print(unit[0])
                    #print(unit[1])
                    #print(unit[2])
                    #print(unit[3])
                    #print(unit[4])

                    #if line[0:2] == b'\x1C\x20':
                    #    print("Ohm")
                    #if line[0:2] == b'\x18\x20':
                    #    print("beep")
                    #if line[0:1] == b'\x1e':
                    #    print("V DC")
                    #if line[0:1] == b'\x1d':
                    #    print("V AC")
                    #if line[0:2] == b'\x1c\x2e':
                    #    print("Hz")
                    #if line[0:2] == b'\x18\x2e':
                    #    print("Temp")

                    return crap_to_number(num, unit, acdc)
                #if (len(line) == 14) and (line[5] == 0x20):
                #    try:
                #        value = float( line[0:5].decode("ascii") )

                #        if line[6] == 0x31:
                #            value /= 10
                #        elif line[6] == 0x32:
                #            value /= 100
                #        elif line[6] == 0x33:
                #            value /= 1000
                #        elif line[6] == 0x34:
                #            value /= 10000
                #    except:
                #        value = inf

                #    if (line[9] & 0x80) != 0:
                #        prefix = "µ"
                #    elif (line[9] & 0x40) != 0:
                #        prefix = "m"
                #    elif (line[9] & 0x20) != 0:
                #        prefix = "k"
                #    elif (line[9] & 0x20) != 0:
                #        prefix = "M"
                #    else:
                #        prefix = ""

                #    if (line[10] & 0x80) != 0:
                #        unit = "V"
                #    elif (line[10] & 0x40) != 0:
                #        unit = "A"
                #    elif (line[10] & 0x20) != 0:
                #        unit = "Ω"
                #    elif (line[10] & 0x10) != 0:
                #        unit = "hFE"
                #    elif (line[10] & 0x08) != 0:
                #        unit = "Hz"
                #    elif (line[10] & 0x04) != 0:
                #        unit = "F"
                #    elif (line[10] & 0x02) != 0:
                #        unit = "℃"
                #    elif (line[10] & 0x01) != 0:
                #        unit = "℉"
                #    else:
                #        unit = ""

                #    print( f"{value}{prefix}{unit}" )

def read():
    ser = Serial("/dev/ttyUSB0", 2400)
    res = read_peaktech(ser)
    try:
        res = int(res)
    except:
        res = 0
    return res

if __name__  == "__main__":
    port = "/dev/ttyUSB0"

    if len(sys.argv) > 1:
        port = sys.argv[1]

    try:
        with Serial( port , 2400) as ser:
            print(ser.name)
            while True:
                print(read_peaktech(ser))

    except KeyboardInterrupt:
        pass
    except Exception as ex:
        print( "Exception:", ex )