from django.contrib import admin
from django.contrib.admin.utils import reverse_field_path
from django.db.models import Max, Min
from django.db.models.fields import DecimalField, FloatField, IntegerField, AutoField
from .forms import RangeNumericForm, SingleNumericForm, SliderNumericForm
class NumericFilterModelAdmin(admin.ModelAdmin):
class Media:
css = {
'all': (
'js/nouislider.min.css',
'css/admin-numeric-filter.css',
)
}
js = (
'js/wNumb.min.js',
'js/nouislider.min.js',
'js/admin-numeric-filter.js',
)
class SingleNumericFilter(admin.FieldListFilter):
request = None
parameter_name = None
template = 'admin/filter_numeric_single.html'
def __init__(self, field, request, params, model, model_admin, field_path):
super().__init__(field, request, params, model, model_admin, field_path)
if not isinstance(field, (DecimalField, IntegerField, FloatField, AutoField)):
raise TypeError('Class {} is not supported for {}.'.format(type(self.field), self.__class__.__name__))
self.request = request
if self.parameter_name is None:
self.parameter_name = self.field.name
if self.parameter_name in params:
value = params.pop(self.parameter_name)
self.used_parameters[self.parameter_name] = value
def queryset(self, request, queryset):
if self.value():
return queryset.filter(**{self.parameter_name: self.value()})
def value(self):
return self.used_parameters.get(self.parameter_name, None)
def expected_parameters(self):
return [self.parameter_name]
def choices(self, changelist):
return ({
'request': self.request,
'parameter_name': self.parameter_name,
'form': SingleNumericForm(name=self.parameter_name, data={self.parameter_name: self.value()}),
}, )
class RangeNumericFilter(admin.FieldListFilter):
request = None
parameter_name = None
template = 'admin/filter_numeric_range.html'
def __init__(self, field, request, params, model, model_admin, field_path):
super().__init__(field, request, params, model, model_admin, field_path)
if not isinstance(field, (DecimalField, IntegerField, FloatField, AutoField)):
raise TypeError('Class {} is not supported for {}.'.format(type(self.field), self.__class__.__name__))
self.request = request
if self.parameter_name is None:
self.parameter_name = self.field.name
if self.parameter_name + '_from' in params:
value = params.pop(self.parameter_name + '_from')
self.used_parameters[self.parameter_name + '_from'] = value
if self.parameter_name + '_to' in params:
value = params.pop(self.parameter_name + '_to')
self.used_parameters[self.parameter_name + '_to'] = value
def queryset(self, request, queryset):
filters = {}
value_from = self.used_parameters.get(self.parameter_name + '_from', None)
if value_from is not None and value_from != '':
filters.update({
self.parameter_name + '__gte': self.used_parameters.get(self.parameter_name + '_from', None),
})
value_to = self.used_parameters.get(self.parameter_name + '_to', None)
if value_to is not None and value_to != '':
filters.update({
self.parameter_name + '__lte': self.used_parameters.get(self.parameter_name + '_to', None),
})
return queryset.filter(**filters)
def expected_parameters(self):
return [
'{}_from'.format(self.parameter_name),
'{}_to'.format(self.parameter_name),
]
def choices(self, changelist):
return ({
'request': self.request,
'parameter_name': self.parameter_name,
'form': RangeNumericForm(name=self.parameter_name, data={
self.parameter_name + '_from': self.used_parameters.get(self.parameter_name + '_from', None),
self.parameter_name + '_to': self.used_parameters.get(self.parameter_name + '_to', None),
}),
}, )
class SliderNumericFilter(RangeNumericFilter):
MAX_DECIMALS = 7
STEP = None
template = 'admin/filter_numeric_slider.html'
field = None
def __init__(self, field, request, params, model, model_admin, field_path):
super().__init__(field, request, params, model, model_admin, field_path)
self.field = field
parent_model, reverse_path = reverse_field_path(model, field_path)
if model == parent_model:
self.q = model_admin.get_queryset(request)
else:
self.q = parent_model._default_manager.all()
def choices(self, changelist):
total = self.q.all().count()
min_value = self.q.all().aggregate(
min=Min(self.parameter_name)
).get('min', 0)
if total > 1:
max_value = self.q.all().aggregate(
max=Max(self.parameter_name)
).get('max', 0)
else:
max_value = None
if isinstance(self.field, (FloatField, DecimalField)):
decimals = self.MAX_DECIMALS
step = self.STEP if self.STEP else self._get_min_step(self.MAX_DECIMALS)
else:
decimals = 0
step = self.STEP if self.STEP else 1
return ({
'decimals': decimals,
'step': step,
'parameter_name': self.parameter_name,
'request': self.request,
'min': min_value,
'max': max_value,
'value_from': self.used_parameters.get(self.parameter_name + '_from', min_value),
'value_to': self.used_parameters.get(self.parameter_name + '_to', max_value),
'form': SliderNumericForm(name=self.parameter_name, data={
self.parameter_name + '_from': self.used_parameters.get(self.parameter_name + '_from', min_value),
self.parameter_name + '_to': self.used_parameters.get(self.parameter_name + '_to', max_value),
})
}, )
def _get_min_step(self, precision):
result_format = '{{:.{}f}}'.format(precision - 1)
return float(result_format.format(0) + '1')
