from django.http import HttpResponse, HttpResponseRedirect
from django.shortcuts import render, get_object_or_404
from django.urls import reverse
from django.utils import timezone

from .models import Event, EventRegistration, TimeSlot


def index(request):
    events = Event.objects.filter(date__gte=timezone.now().date()).order_by("date")[:20]

    events_data = [
        {"event": event, "timeslots": [{"timeslot":        timeslot,
                                        "my_registration": timeslot.registration_of(request.user)}
                                       for timeslot in TimeSlot.objects.filter(event_id=event.id)]}
        for event in events
    ]
    return render(request, "events/index.html", {"events": events_data})


def register(request, timeslot_id):
    if request.method != "POST":
        return HttpResponse(status_code=405)

    if not request.user.has_ugent_info:
        raise ValueError("User has missing UGent info missing")

    timeslot = get_object_or_404(TimeSlot, id=timeslot_id)

    timeslot.eventregistration_set.create(
        state=EventRegistration.INTERESTED,
        time_slot=timeslot,
        user=request.user,
    )
    return HttpResponseRedirect(reverse("events:index") + f"#{timeslot.id}")


def deregister(request, timeslot_id):
    if request.method != "POST":
        return HttpResponse(status_code=405)

    registration = get_object_or_404(EventRegistration, time_slot=timeslot_id, user=request.user)
    registration.delete()
    return HttpResponseRedirect(reverse("events:index") + f"#{timeslot_id}")