Cobra Tag Exercise

cobra.py

import getopt
import sys
from datetime import datetime
from time import sleep
import pytz

#### CRC-16 MODBUS Stuff. Included so we do all in one script ####

INITIAL_MODBUS = 0xFFFF

table = (
    0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
    0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
    0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
    0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
    0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
    0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
    0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
    0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
    0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
    0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
    0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
    0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
    0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
    0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
    0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
    0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
    0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
    0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
    0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
    0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
    0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
    0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
    0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
    0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
    0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
    0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
    0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
    0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
    0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
    0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
    0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
    0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040
)


def calcByte( ch, crc):
    """Given a new Byte and previous CRC, Calc a new CRC-16"""
    if type(ch) == type("c"):
        by = ord(ch)
    else:
        by = ch
    crc = (crc >> 8) ^ table[(crc ^ by) & 0xFF]
    return (crc & 0xFFFF)


def calcString(st, crc=INITIAL_MODBUS):
    """Given a binary string and starting CRC, Calc a final CRC-16"""
    for ch in st:
        crc = (crc >> 8) ^ table[(crc ^ ord(ch)) & 0xFF]
    return crc


#### Cobra Generation ####

def generate_cobra_data(device_id):
    """Generates Cobra read"""
    prologue = "$69"
    common_data = "0068CB%s%s+000101AAAA21209500010010F1"
    date_time = datetime.utcnow().today().strftime('%Y%m%d%H%M%S')
    data = common_data % (device_id, date_time)
    crc = calcString(data)
    return prologue + data + hex(crc).split('x')[1]


def print_cobra_header(raw_read):
    """Prints out Cobra header from raw read"""
    if len(raw_read) < 42:
        print_usage_and_exit('No header')

    type_mapping = {'CB' : 'Savi Cobra'}

    try:
        print "\nHeader:\n-------"
        print "%-25s%s" % ("Prologue:", raw_read[0:3])
        print "%-25s%d" % ("Length:", int(raw_read[3:7]))
        print "%-25s%s ('%s')" % ("Type:", raw_read[7:9], type_mapping[raw_read[7:9]])
        print "%-25s%s" % ("Device ID:", raw_read[9:23])
        read_date_time = "%4s-%2s-%2s %2s:%2s:%2s%3s" % (
            raw_read[23:27], raw_read[27:29], raw_read[29:31],
            raw_read[31:33], raw_read[33:35], raw_read[35:37], raw_read[37:40])
        print "%-25s%s" % ("Date-Time:", read_date_time)
    except:
        print_usage_and_exit('Invalid header')


def print_cobra_status(raw_read, idx):
    """Prints out Cobra Status payload from raw read and position index"""
    update_period_map = {'2': '15 minutes'}
    sample_period_map = {'1': '5 minutes'}
    gps_status_map = {'1': 'Disabled', '2': 'Enabled'}

    try:
        m_type = raw_read[idx:idx+2]
        if int(m_type) != 1:
            msg = 'Payload starting at %d is not a Status Message' % idx
            print_usage_and_exit(msg)
        firmware_ver = raw_read[idx+2:idx+6]
        tag_upd_period = update_period_map[raw_read[idx+6:idx+7]]
        sample_upd_period = sample_period_map[raw_read[idx+7:idx+8]]
        gps_status = gps_status_map[raw_read[idx+8:idx+9]]
        battery_level = raw_read[idx+9:idx+12]
        calls_attempted = raw_read[idx+12:idx+16]
        calls_completed = raw_read[idx+16:idx+20]
        call_status = raw_read[idx+20:idx+22]

        print "\nStatus:\n-------"
        print "%-25s%s" % ("Firmware Version:", firmware_ver)
        print "%-25s%s" % ("Tag Update Period:", tag_upd_period)
        print "%-25s%s" % ("Sample Update Period:", sample_upd_period)
        print "%-25s%s" % ("AGPS Status:", gps_status)
        print "%-25s%.2f" % ("Battery Level:", float(battery_level)/100.0)
        print "%-25s%d" % ("Calls Attempted:", int(calls_attempted))
        print "%-25s%d" % ("Calls Completed:", int(calls_completed))
        print "%-25s%s" % ("Call Status:", call_status)

    except:
        msg = 'Payload starting at %d is not a Status Message' % idx
        print_usage_and_exit(msg)


def print_cobra_agps(raw_read, start_position):
    """TODO"""
    print "postion"


def print_cobra_data(raw_read, target_url):
    """Prints out parsed Cobra tag read, telnet instructions, and raw data"""
    port_map = {'CB' : 9999}
    payload_len_map = {'01': 22}

    print "\n===========\nPARSED READ\n==========="

    print_cobra_header(raw_read)

    num_payloads = int(raw_read[40:42])
    print "%-15s%d" % ("Payload Count:", num_payloads)

    if num_payloads > 0:
        postion = 42 # Header Length
        for payload in range (1, num_payloads + 1):
            msg_type = raw_read[postion:postion+2]
            if msg_type == '01': 
                print_cobra_status(raw_read, postion)
                postion += payload_len_map[msg_type]
            elif msg_type == '02':
                print "TODO"
                # print_cobra_agps(raw_read, postion)

    print "\nCRC:\n----\n%s\n" % raw_read[postion:postion+4]

    print "\n========\nRAW READ\n========"
    print "telnet %s %d" % (target_url, port_map[raw_read[7:9]])
    print "%s\n" % raw_read 


############################## Main script ##############################

# Print usage help and applicable error text
def print_usage_and_exit(msg=None):
    print "\nUsage: %s [-h][-d][-u]" % sys.argv[0]
    print "\t-h\tPrint usage help"
    print "\t-d\tDeviceId to use (otherwise default to TestDeviceXXXXX)"
    print "\t-u\tURL to send message (otherwise default to PROD)"
    if msg: print msg + "\n"
    sys.exit(2)


def main(argv):
    """Main method"""
    COBRA_ID_LEN = 14
    DEFAULT_DEVICE_ID = 'TestDeviceXXXX' # Must be 14 characters
    DEFAULT_URL = 'iota-gprs.savitechnology.com'

    device_id = None
    endpoint_url = None

    try:
        opts, args = getopt.getopt(argv, "hd:u:")
    except getopt.GetoptError:
        print_usage_and_exit('Could not parse options')

    for opt, arg in opts:
        if opt == '-h':
            print_usage_and_exit()
        elif opt == '-d':
            input_device_id = arg
            input_len = len(input_device_id)
            if input_len < COBRA_ID_LEN:
                padding = "X" * (COBRA_ID_LEN - input_len)
                device_id = input_device_id + padding
            else:
                device_id = input_device_id[0:14]
        elif opt == '-u':
            endpoint_url = arg 

    if not(device_id):
        device_id = DEFAULT_DEVICE_ID

    if not(endpoint_url):
        endpoint_url = DEFAULT_URL

    generated_read = generate_cobra_data(device_id)
    print_cobra_data(generated_read, endpoint_url)

if __name__ == '__main__':
    main(sys.argv[1:])