import datetime from django.utils import six def id_number_checksum(gd): """ Calculates a Swedish ID number checksum, using the "Luhn"-algoritm """ n = s = 0 for c in (gd['year'] + gd['month'] + gd['day'] + gd['serial']): tmp = ((n % 2) and 1 or 2) * int(c) if tmp > 9: tmp = sum([int(i) for i in str(tmp)]) s += tmp n += 1 if (s % 10) == 0: return 0 return (((s // 10) + 1) * 10) - s def validate_id_birthday(gd, fix_coordination_number_day=True): """ Validates the birth_day and returns the datetime.date object for the birth_day. If the date is an invalid birth day, a ValueError will be raised. """ today = datetime.date.today() day = int(gd['day']) if fix_coordination_number_day and day > 60: day -= 60 if gd['century'] is None: # The century was not specified, and need to be calculated from todays date current_year = today.year year = int(today.strftime('%Y')) - int(today.strftime('%y')) + int(gd['year']) if ('%s%s%02d' % (gd['year'], gd['month'], day)) > today.strftime('%y%m%d'): year -= 100 # If the person is older than 100 years if gd['sign'] == '+': year -= 100 else: year = int(gd['century'] + gd['year']) # Make sure the year is valid # There are no swedish personal identity numbers where year < 1800 if year < 1800: raise ValueError # ValueError will be raise for invalid dates birth_day = datetime.date(year, int(gd['month']), day) # birth_day must not be in the future if birth_day > today: raise ValueError return birth_day def format_personal_id_number(birth_day, gd): # birth_day.strftime cannot be used, since it does not support dates < 1900 return six.text_type(str(birth_day.year) + gd['month'] + gd['day'] + gd['serial'] + gd['checksum']) def format_organisation_number(gd): if gd['century'] is None: century = '' else: century = gd['century'] return six.text_type(century + gd['year'] + gd['month'] + gd['day'] + gd['serial'] + gd['checksum']) def valid_organisation(gd): return gd['century'] in (None, 16) and \ int(gd['month']) >= 20 and \ gd['sign'] in (None, '-') and \ gd['year'][0] in ('2', '5', '7', '8', '9') # group identifier