from django import forms

from django.db.models import Field

from .. import Vector

# https://docs.djangoproject.com/en/5.0/howto/custom-model-fields/

class VectorField(Field):

description = 'Vector'

empty_strings_allowed = False

def __init__(self, *args, dimensions=None, **kwargs):

self.dimensions = dimensions

super().__init__(*args, **kwargs)

def deconstruct(self):

name, path, args, kwargs = super().deconstruct()

if self.dimensions is not None:

kwargs['dimensions'] = self.dimensions

return name, path, args, kwargs

def db_type(self, connection):

if self.dimensions is None:

return 'vector'

return 'vector(%d)' % self.dimensions

def from_db_value(self, value, expression, connection):

return Vector._from_db(value)

def to_python(self, value):

if value is None or isinstance(value, Vector):

return value

elif isinstance(value, str):

return Vector._from_db(value)

else:

return Vector(value)

def get_prep_value(self, value):

return Vector._to_db(value)

def value_to_string(self, obj):

return self.get_prep_value(self.value_from_object(obj))

def formfield(self, **kwargs):

return super().formfield(form_class=VectorFormField, **kwargs)

class VectorWidget(forms.TextInput):

def format_value(self, value):

if isinstance(value, Vector):

value = value.to_list()

return super().format_value(value)

class VectorFormField(forms.CharField):

widget = VectorWidget

def to_python(self, value):

if isinstance(value, str) and value == '':

return None

return super().to_python(value)