kers/events/admin.py

from django import forms
from django.contrib import admin

from .models import Event, EventRegistration, TimeSlot


class TimeSlotFormSet(forms.BaseInlineFormSet):
    def __init__(self, *args, **kwargs):
        kwargs["initial"] = [
            {"time": TimeSlot.EVENING}
        ]
        super().__init__(*args, **kwargs)


class RegistrationFormSet(forms.BaseInlineFormSet):
    def __init__(self, *args, **kwargs):
        kwargs["initial"] = [
            {"state": EventRegistration.ADMITTED}
        ]
        super().__init__(*args, **kwargs)


class TimeSlotInline(admin.StackedInline):
    model = TimeSlot
    extra = 1
    formset = TimeSlotFormSet


class RegistrationInline(admin.TabularInline):
    model = EventRegistration
    extra = 1
    formset = RegistrationFormSet
#

class EventAdmin(admin.ModelAdmin):
    inlines = [TimeSlotInline]


class TimeSlotAdmin(admin.ModelAdmin):
    inlines = [RegistrationInline]


admin.site.register(Event, EventAdmin)
admin.site.register(TimeSlot, TimeSlotAdmin)