import datetime

from crispy_forms.helper import FormHelper
from crispy_forms.layout import Submit
from django.core.exceptions import PermissionDenied
from django.forms import TextInput
from django.forms.models import ModelForm
from django.http import HttpResponse
from django.shortcuts import redirect, render
from django.views.generic.edit import CreateView, UpdateView
from rest_framework import status
from rest_framework.decorators import api_view
from rest_framework.response import Response

from location_field.widgets import LocationWidget

from .models import Event, EventParticipation
from .serializers import ParticipationSerializer

# ---------------------------------------- API ---------------------------------------------------------


@api_view(["GET", "PUT"])
def event_api(request, username=None, eventId=None):
    try:
        participationQs = EventParticipation.objects.filter(
            event__date__gte=datetime.date.today()
        )
        if username:
            participationQs = EventParticipation.objects.filter(user__username=username)
        if eventId:
            participationQs = participationQs.filter(event__pk=eventId)
    except EventParticipation.DoesNotExist:
        return HttpResponse(status=404)

    if request.method == "GET":
        serializer = ParticipationSerializer(participationQs, many=True)
        return Response(serializer.data)

    elif request.method == "PUT":
        serializer = ParticipationSerializer(data=request.data, many=True)
        if serializer.is_valid():
            for item in serializer.validated_data:
                event = item.get("event")
                user_obj = item.get("user")
                if not (
                    EventParticipation.isMember(request.user)
                    or EventParticipation.isAdmin(request.user)
                ):
                    return Response(
                        {"error": "Permission denied - not a member"},
                        status=status.HTTP_403_FORBIDDEN,
                    )
                # Allow users to update their own participation
                # Admins can update anyone's participation
                if user_obj.pk != request.user.pk:
                    if not EventParticipation.isAdmin(request.user):
                        return Response(
                            {"error": "Permission denied - can only update own status"},
                            status=status.HTTP_403_FORBIDDEN,
                        )

            instances = serializer.save()
            # Re-serialize the saved instances to return proper data
            response_serializer = ParticipationSerializer(instances, many=True)
            return Response(response_serializer.data)
        else:
            import logging

            logger = logging.getLogger(__name__)
            logger.error(f"API validation errors: {serializer.errors}")
            logger.error(f"Request data: {request.data}")
            return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)


# ------------------------------------ Normal Views ----------------------------------------------------


def eventplanning(request):
    """
    View for a specific user, to edit his events
    """
    # non-members see the grid - but cannot edit anything
    if not EventParticipation.isMember(request.user):
        return events_grid(request)

    # All events in the future sorted by date
    all_future_events = list(
        Event.objects.filter(date__gte=datetime.date.today()).order_by("date")
    )

    for e in all_future_events:
        e.participation = EventParticipation.get_or_create(event=e, user=request.user)

    context = {"events": all_future_events}
    return render(request, "eventplanner/eventplanning_view.html", context)


def events_grid(request):
    usernames = [u.username for u in EventParticipation.members()]

    all_future_events = list(
        Event.objects.filter(date__gte=datetime.date.today()).order_by("date")
    )

    for e in all_future_events:
        e.participation = [
            EventParticipation.get_or_create(event=e, user=u)
            for u in EventParticipation.members()
        ]

    context = {"events": all_future_events, "usernames": usernames}

    return render(request, "eventplanner/events_grid.html", context)


def deleteEvent(request, pk):
    if not EventParticipation.isAdmin(request.user):
        raise PermissionDenied
    Event.objects.get(pk=pk).delete()
    return redirect("eventplanner:events_grid")


# ------------------------------------ Detail Views ----------------------------------------------------


class EventForm(ModelForm):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.helper = FormHelper()
        self.helper.form_class = "form-horizontal"
        self.helper.add_input(Submit("submit", "Speichern"))

    class Meta:
        model = Event
        fields = [
            "type",
            "short_desc",
            "date",
            "end_date",
            "time",
            "meeting_time",
            "location",
            "map_location",
            "desc",
        ]

        widgets = {
            "location": TextInput(),
            "map_location": LocationWidget(),
        }


class EventUpdate(UpdateView):
    form_class = EventForm
    model = Event
    template_name_suffix = "_update_form"
    success_url = "."

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["viewtype"] = "update"
        return context


class EventCreate(CreateView):
    form_class = EventForm
    model = Event
    template_name_suffix = "_update_form"
    success_url = "."

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["viewtype"] = "create"
        return context