def _decompress_historic_datetime(
historic_datetime: HistoricDateTime) -> List:
year = historic_datetime.year
season, month, day, time = None, None, None, None
hour, minute, second = (
historic_datetime.hour,
historic_datetime.minute,
historic_datetime.second,
)
if historic_datetime.use_ybp:
year, year_system = historic_datetime.year_bp, YBP
elif historic_datetime.year_bce:
year, year_system = historic_datetime.year_bce, BCE
else:
year_system = CE
if historic_datetime.season_is_known:
season = get_season_from_month(historic_datetime.month)
if historic_datetime.month_is_known:
month = historic_datetime.month
if historic_datetime.day_is_known:
day = historic_datetime.day
if 0 in {hour, minute, second} or 1 in {hour, minute, second}:
time = None
else:
time = historic_datetime.strftime('%H:%M:%S.%f')
return [year, year_system, season, month, day, time]
def to_python(
self, historic_datetime: Optional[Union[DateTime, str]]
) -> Optional[HistoricDateTime]:
"""
Convert the value into the correct Python object.
This method acts as the reverse of value_to_string(), and is also called in clean().
"""
if not historic_datetime:
return None
elif isinstance(historic_datetime, HistoricDateTime):
return historic_datetime
elif isinstance(historic_datetime, datetime):
# TODO: consider effect of timezones
if settings.USE_TZ and is_naive(historic_datetime):
historic_datetime = make_aware(historic_datetime)
return HistoricDateTime(
historic_datetime.year,
historic_datetime.month,
historic_datetime.day,
historic_datetime.hour,
historic_datetime.minute,
historic_datetime.second,
historic_datetime.microsecond,
)
elif isinstance(historic_datetime, str):
raise TypeError
def decompress(self, datetime_value: Union[date, str, Any]):
"""
"Decompresses" a Python value into a list of values to populate the widget.
The input value can be assumed valid, but not necessarily non-empty.
https://docs.djangoproject.com/en/3.1/ref/forms/widgets/#django.forms.MultiWidget.decompress
"""
nones = (None, None, None, None, None, None)
hour = minute = second = ms = 0
if not isinstance(datetime_value, HistoricDateTime):
if isinstance(datetime_value, str):
year, month, day, hour, minute, second, ms = self._parse_string(
datetime_value)
elif isinstance(datetime_value, (datetime, date)):
year, month, day = (
datetime_value.year,
datetime_value.month,
datetime_value.day,
)
if isinstance(datetime_value, datetime):
hour, minute, second, ms = (
datetime_value.hour,
datetime_value.minute,
datetime_value.second,
datetime_value.microsecond,
)
else:
return nones
# Convert value to HistoricDateTime
datetime_value = HistoricDateTime(year, month, day, hour, minute,
second, ms)
return self._decompress_historic_datetime(datetime_value)
def date_sorter(
model_instance: Union[SearchableDatedModel, Dict]) -> HistoricDateTime:
"""Return the value used to sort the model instance by date."""
get_date = getattr(model_instance, 'get_date', None)
if get_date is not None:
date = get_date()
elif isinstance(model_instance, dict):
date = model_instance.get('date')
else:
date = getattr(model_instance, 'date', None)
if not date:
date = HistoricDateTime(1, 1, 1, 0, 0, 0)
# Display precise dates before ranges, e.g., "1500" before "1500 – 2000"
if getattr(model_instance, 'end_date', None):
microsecond = date.microsecond + 1
date = date.replace(microsecond=microsecond)
return date
def value_from_datadict(self, datadict, files, name) -> Optional[str]:
"""Compress the input value into a format that can be saved to the db."""
decompressed_values = super().value_from_datadict(
datadict, files, name)
if len(decompressed_values) != 2:
raise ValueError(
f'Wrong number of values: {len(decompressed_values)}')
year, year_system = decompressed_values
if not year:
return None
year, second, microsecond = get_year(year, year_system)
# Build datetime obj
dt = HistoricDateTime(year,
1,
1,
1,
1,
second,
microsecond=microsecond)
# Return date-parsable string for db
return dt.strftime('%Y-%m-%d %H:%M:%S.%f')
def from_db_value(self, datetime_value: Optional[DateTime], expression,
connection) -> Optional[HistoricDateTime]:
"""
Convert a value as returned by the database to a Python object.
This method is the reverse of get_prep_value().
https://docs.djangoproject.com/en/3.1/ref/models/fields/#django.db.models.Field.from_db_value
"""
if datetime_value is None:
return datetime_value
# TODO: consider effect of timezones
if settings.USE_TZ and is_naive(datetime_value):
datetime_value = make_aware(datetime_value)
return HistoricDateTime(
datetime_value.year,
datetime_value.month,
datetime_value.day,
datetime_value.hour,
datetime_value.minute,
datetime_value.second,
datetime_value.microsecond,
)
def _datetime_from_datadict_values(year, year_system, season, month, day):
# Figure out year
year, second, microsecond = get_year(year, year_system)
# Figure out date precision
hour, minute = 0, 0
if not season and not month:
hour, minute, second = 1, 1, second or 1
elif season and not month:
month = get_month_from_season(season)
hour, minute, second = 0, 1, second or 1
elif month and not day:
hour, minute, second = 0, 0, second or 1
month, day = (month or 1), (day or 1)
# Return datetime object
return HistoricDateTime(
int(year),
int(month),
int(day),
int(hour),
int(minute),
int(second),
microsecond=int(microsecond),
)