# from django.shortcuts import render
from datetime import datetime
from itertools import groupby
from typing import Callable

from django.db.models import Q
from django.db.models.functions import TruncMonth
from rest_framework import viewsets, mixins
from rest_framework.decorators import action
from rest_framework.permissions import IsAuthenticated
from rest_framework.renderers import StaticHTMLRenderer
from rest_framework.response import Response
from rest_framework.viewsets import GenericViewSet

from myapi.renderers import LatexRenderer, PlainTextRenderer
from myapi.serializers import FilmSerializer
from myapi.models import Film
import myapi.services.com_service as com


class AdminFilmViewSet(viewsets.ModelViewSet):
    queryset = Film.objects.all().order_by("-projection_date")
    serializer_class = FilmSerializer
    permission_classes = [IsAuthenticated]

    def general_com_view(self, com_function: Callable[[Film], str]):
        film: Film = self.get_object()
        preview_text = com_function(film)
        return Response(preview_text)

    # TODO confirm that latex renderer is not a problem
    @action(detail=True, methods=["GET"], renderer_classes=[LatexRenderer])
    def bocal(self, request, pk=None):
        return self.general_com_view(com.bocal)

    @action(detail=True, methods=["GET"])
    def facebook(self, request, pk=None):
        film: Film = self.get_object()
        fb_text = com.facebook_text(film)
        fb_title = com.facebook_title(film)
        return Response(
            {"title": fb_title, "body": fb_text, "banner_link": film.banner_link}
        )

    @action(detail=True, methods=["GET"], renderer_classes=[StaticHTMLRenderer])
    def newsletter(self, request, pk=None):
        return self.general_com_view(com.mail)

    @action(detail=True, methods=["GET"], renderer_classes=[PlainTextRenderer])
    def ics(self, request, pk=None):
        return self.general_com_view(com.ics)


class FilmViewSet(mixins.RetrieveModelMixin, GenericViewSet):
    serializer_class = FilmSerializer

    def get_queryset(self):
        queryset = Film.objects.all().filter(is_confirmed=True)
        past = self.request.query_params.get("period", "future") == "past"
        date_filter = (
            Q(projection_date__date__lt=datetime.now())
            if past
            else Q(projection_date__date__gte=datetime.now())
        )
        ordering = f"{'-' if past else ''}projection_date"
        return queryset.filter(date_filter).order_by(ordering)

    @action(detail=False, methods=["GET"])
    def home(self, request, *args, **kwargs):
        queryset = self.filter_queryset(self.get_queryset())[:5]
        serializer = self.get_serializer(queryset, many=True)
        return Response(serializer.data)

    @action(detail=False, methods=["GET"])
    def calendar(self, request):
        qs = self.get_queryset().annotate(
            projection_month=TruncMonth("projection_date")
        )
        page = self.paginate_queryset(qs) or qs
        grouped = groupby(page, lambda f: f.projection_month)
        data = [
            {
                "projection_month": month.strftime("%B %Y"),
                "films": FilmSerializer(monthly_data, many=True).data,
            }
            for (month, monthly_data) in grouped
        ]
        return self.get_paginated_response(data)