Wii Fit U Parser

wii_fit_u_parser.py

#!/usr/bin/python
#
# Based on the Wii Fit parser found here: https://gist.github.com/tewalds/86170c18ecf6f211a9bc
#
# Extract data from a Wii Fit U .dat file to a CSV.
# Add the -p flag to include user name, date of birth and current height to the output.
# File paths can be passed to the script. If none are passed, 'Step0.dat' will be used.
# 
#
# 0xD = Name start
# 0x23 = Height in cm (1)
# 0x24 = DOB (yyyymmdd) (4)
# 0x5AD3 = Start of measures (22 each):
#      0 = Date (4)
#      4 = Weight (kg) (2)
#      6 = BMI (2)
#      8 = Right balance percentage (2)
#     15 = Body test age (1)
#

import struct
import csv
import argparse
import sys

parser = argparse.ArgumentParser(description="Extract data from a Wii Fit U .dat file to CSV")
parser.add_argument(
    "-p",
    "--player-data",
    action="store_true",
    help="include player data (name, DOB, height) at the top of the CSV file",
)
parser.add_argument(
    'files',
    nargs='*',
    metavar='files',
    help='One or more .dat files to parse',
    default=['Step0.dat']
)
args = parser.parse_args()


# Converts hex values to integers witout performing a value conversion
# E.g. 0x19 0x90 is converted to 1990
# Required for DOB
def hex_bytes_to_integer(hex_value):
    num_bytes = len(hex_value)
    nibbles = []

    int_value = int.from_bytes(hex_value, byteorder='big')

    for i in range(num_bytes * 2):
        nibble = (int_value >> (4 * i)) & 0x0F
        nibbles.insert(0, nibble)

    return int(''.join(map(str, nibbles)))


for file in args.files:
    with open(file, 'rb') as input_file:
        input_file.seek(int('0xD', base=16))
        player_name = ''

        for x in range(10):     # maximum name length of 10 characters
            char = input_file.read(1)

            if char == b'\x00':
                break

            player_name += str(char, 'UTF-8')
            input_file.seek(1, 1)

        if len(player_name) == 0:
            print("Error reading player name")
            sys.exit(1)

        with open(f'WiiFitU_{player_name:s}.csv', encoding='utf-8', mode='w') as out_file:
            writer = csv.writer(out_file, delimiter=',', quotechar="'", quoting=csv.QUOTE_MINIMAL)

            if args.player_data:
                input_file.seek(int('0x23', base=16), 0)
                height = ord(input_file.read(1))
                dob_year = hex_bytes_to_integer(input_file.read(2))
                dob_month = hex_bytes_to_integer(input_file.read(1))
                dob_day = hex_bytes_to_integer(input_file.read(1))

                writer.writerow(['Name:', player_name])
                writer.writerow(['DOB:', f'{dob_year}-{dob_month:02d}-{dob_day:02d}'])
                writer.writerow(['Current Height:', str(height) + 'cm'])
                writer.writerow([])

            writer.writerow(['Date', 'Weight (kg)', 'BMI', 'Right Balance', 'Fit Age'])
            input_file.seek(int('0x5AD3', base=16), 0)

            while True:
                record = input_file.read(21)

                if record[0] == 0:
                    break

                packed_date, weight, bmi, balance, fit_age = struct.unpack('>i3H4xB',record[0:15])

                # Unpack the date: http://stackoverflow.com/questions/719129/datetime-hex-format
                year   = packed_date >> 20
                month  = (packed_date >> 16 & 0xf) + 1
                day    = packed_date >> 11 & 0x1f
                hour   = packed_date >> 6 & 0x1f
                minute = packed_date & 0x3f

                date = f'{year}-{month:02d}-{day:02d} {hour:02d}:{minute:02d}'
                weight = weight / 10
                bmi = bmi / 100
                balance = f'{balance / 10}%'

                if fit_age == 0:
                    fit_age = ''

                writer.writerow([date, weight, bmi, balance, fit_age])