#!/usr/bin/env python3

import argparse

import sys

import struct

import time

TEXT_LOG_HEADER = 'datetime,temperature,humidity'

LOG_PREAMBLE = 'Log_v'

PREAMBLE_END_TOKEN = b'\n'

ENDIANNESS_BYTES = (78 << 24) | (185 << 16) | (219 << 8) | (110)

def get_cli_args():

parser = argparse.ArgumentParser(formatter_class=argparse.ArgumentDefaultsHelpFormatter, description="Convert an optimized binary log to a readable, text log.")

parser.add_argument('binary_logfile', help="Path to the log file in binary format.")

parser.add_argument('output_filepath', help="Path to write the text output to.")

return parser.parse_args()

def readcheck(binfile, numbytes, exit=False):

b = binfile.read(numbytes)

if len(b) < numbytes:

if exit:

print("Log data corrupted.")

sys.exit(-1)

else:

return b''

return b

def v1_conversion(binfile, txtfile):

b = readcheck(binfile, 4, True)

signature = struct.unpack('<I', b)[0]

if signature == ENDIANNESS_BYTES:

endianness = '<'

else:

signature = struct.unpack('>I', b)[0]

if signature == ENDIANNESS_BYTES:

endianness = '>'

else:

print("Invalid log file endianness. Exiting.")

sys.exit(-1)

b = readcheck(binfile, 4, True)

int_size = struct.unpack(f'{endianness}I', b)[0]

int_format = 'I' if int_size == 4 else 'Q'

b = readcheck(binfile, 4, True)

float_size = struct.unpack(f'{endianness}I', b)[0]

float_format = 'f' if float_size == 4 else 'd'

print(TEXT_LOG_PREAMBLE + '1', file=txtfile)

print(TEXT_LOG_HEADER, file=txtfile)

while True:

b = binfile.read(4)

if len(b) < 4: break

unixtime = struct.unpack(f'{endianness}I', b)[0]

b = binfile.read(4)

if len(b) < 4:

print("Log data corrupted.")

sys.exit(-1)

temp = struct.unpack(f'{endianness}{float_format}', b)[0]

#b = binfile.read(4)

#if len(b) < 4:

# print("Log data corrupted.")

# sys.exit(-1)

#hum = struct.unpack(f'{endianness}{float_format}', b)[0]

timestr = time.strftime("%Y-%m-%d,%H:%M:%S", time.gmtime(unixtime))

print(f"{timestr},{temp}", file=txtfile)

conversion_table = {

1 : v1_conversion

}

if __name__ == "__main__":

cli_args = get_cli_args()

with open(cli_args.binary_logfile, 'rb') as binfile, open(cli_args.output_filepath, 'w') as txtfile:

header = ''

while True:

b = binfile.read(1)

if b == b'\x00' or b == b'': break

header += b.decode()

if b == PREAMBLE_END_TOKEN: break

if header.startswith(LOG_PREAMBLE):

version = int(header[len(LOG_PREAMBLE):])

conversion_table[version](binfile, txtfile)

else:

print("Invalid or unknown log preamble. Exiting.")

sys.exit(-1)