"""Common field types."""
from typing import Union
from dateutil.relativedelta import relativedelta
from django.contrib.postgres.fields import DateRangeField
from django.contrib.postgres.fields import DateTimeRangeField
from django.core.exceptions import ValidationError
from django.db import models
from django.db.models.expressions import RawSQL
from django.forms import ModelChoiceField
from django.urls import reverse_lazy
from psycopg.types.range import DateRange
from psycopg.types.range import Range
from common import validators
from common.util import TaricDateRange
from common.util import TaricDateTimeRange
from common.widgets import AutocompleteWidget
def get_next_by_max(field):
return lambda: RawSQL(
sql=f'SELECT COALESCE(MAX("{field.column}"), 0) + 1 FROM "{field.model._meta.db_table}"',
params=[],
)
[docs]class NumericSID(models.PositiveIntegerField):
def __init__(self, *args, **kwargs):
kwargs["editable"] = False
kwargs["validators"] = [validators.NumericSIDValidator()]
kwargs["db_index"] = True
kwargs.setdefault("default", get_next_by_max(self))
super().__init__(*args, **kwargs)
[docs] def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
del kwargs["editable"]
del kwargs["validators"]
del kwargs["db_index"]
del kwargs["default"]
return name, path, args, kwargs
[docs]class SignedIntSID(models.IntegerField):
def __init__(self, *args, **kwargs):
kwargs["editable"] = False
kwargs["db_index"] = True
kwargs.setdefault("default", get_next_by_max(self))
super().__init__(*args, **kwargs)
[docs] def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
del kwargs["editable"]
del kwargs["db_index"]
del kwargs["default"]
return name, path, args, kwargs
[docs]class ShortDescription(models.CharField):
def __init__(self, *args, **kwargs):
kwargs["max_length"] = 500
kwargs["blank"] = True
kwargs["null"] = True
super().__init__(*args, **kwargs)
[docs] def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
del kwargs["max_length"]
del kwargs["blank"]
del kwargs["null"]
return name, path, args, kwargs
class LongDescription(models.TextField):
def __init__(self, *args, **kwargs):
kwargs["max_length"] = 20000
kwargs["blank"] = True
kwargs["null"] = True
super().__init__(*args, **kwargs)
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
del kwargs["max_length"]
del kwargs["blank"]
del kwargs["null"]
return name, path, args, kwargs
[docs]class ApplicabilityCode(models.PositiveSmallIntegerField):
def __init__(self, *args, **kwargs):
kwargs["choices"] = validators.ApplicabilityCode.choices
super().__init__(*args, **kwargs)
[docs] def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
del kwargs["choices"]
return name, path, args, kwargs
class TaricDateRangeField(DateRangeField):
"""Model field that converts between `common.util.TaricDateRange` and its
database representation."""
range_type = TaricDateRange
def from_db_value(
self,
value: Union[Range, DateRange, TaricDateRange],
*_args,
**_kwargs,
) -> TaricDateRange:
"""
By default Django ignores the range_type and just returns a Psycopg
DateRange.
Additionally, from the Psycopg docs
(https://www.psycopg.org/psycopg3/docs/basic/pgtypes.html#range-adaptation):
All the PostgreSQL range types are loaded as the Range Python type,
which is a Generic type and can hold bounds of different types.
This method forces the conversion to a TaricDateRange and shifts the
upper date to be inclusive (it is exclusive by default).
"""
if not value:
return value
if isinstance(value, TaricDateRange):
# Avoid re-applying the date shift / inclusive bound change to
# `upper` (i.e. a TaricDateRange instance implies a shift has
# already been applied).
return value
lower = value.lower
upper = value.upper
if not value.upper_inc and not value.upper_inf:
upper = upper - relativedelta(days=1)
return TaricDateRange(lower=lower, upper=upper)
class TaricDateTimeRangeField(DateTimeRangeField):
range_type = TaricDateTimeRange
class AutoCompleteField(ModelChoiceField):
"""
A form field that provides an AutoComplete widget for selecting a model
instance.
Args:
- queryset (QuerySet): A queryset of model instances that will populate the valid choices for the field.
- label (str): (Optional) A label for the field.
- help_text (str): (Optional) Help text for the field.
- url_pattern_name (str): (Optional) A custom pattern name to use for resolving the API source URL of AutoCompleteWidget.
- attrs (dict): (Optional) Additional attributes to pass to AutoCompleteWidget, e.g {"min-length": 2}.
"""
def __init__(self, queryset, url_pattern_name=None, *args, **kwargs):
self.widget = AutocompleteWidget(
attrs={
"label": kwargs.get("label", ""),
"help_text": kwargs.get("help_text", ""),
"source_url": reverse_lazy(
self.get_url_pattern_name(queryset, url_pattern_name),
),
**kwargs.pop("attrs", {}),
},
)
super().__init__(queryset=queryset, *args, **kwargs)
def get_url_pattern_name(self, queryset, url_pattern_name: str | None) -> str:
"""
Determines the URL pattern name to use for resolving the API source URL
of AutocompleteWidget.
If a custom name isn't provided, the name will be based on the
attributes of the model derived from the queryset.
"""
if url_pattern_name is not None:
return url_pattern_name
prefix = getattr(queryset.model, "url_pattern_name_prefix", None)
if not prefix:
prefix = queryset.model._meta.model_name
return f"{prefix}-list"
def prepare_value(self, value):
try:
return self.to_python(value)
except ValidationError:
return None