import django.utils.timezone
from django.core.cache import cache
from django.http import HttpRequest, HttpResponseRedirect
from django.shortcuts import render
from django.urls import reverse

import clubhaus.settings as django_settings
from .exceptions import RateLimitHit, ProxyUsageDetected
from .models import Tobacco, ClubhausEvent, EventDate, EventDateVotes, VotingUser


def bad_request(request, exception, template_name="homepage/400.html"):
    return render(request, template_name, context={"exception": exception}, status=400)


def index(request: HttpRequest) -> django.http.HttpResponse:
    return render(request, 'homepage/index.html', {})


def impressum(request: HttpRequest) -> django.http.HttpResponse:
    return render(request, 'homepage/impressum.html')


def tobacco(request: HttpRequest) -> django.http.HttpResponse:
    context = {'tobaccos': Tobacco.objects.all().order_by('-in_stock')}
    return render(request, 'homepage/tobacco.html', context)


def events(request: HttpRequest) -> django.http.HttpResponse:
    next_events = ClubhausEvent.objects.filter(active=True).order_by('-id')
    if len(next_events) == 1:
        next_event = next_events[0]
        dates = EventDate.objects.filter(event=next_event).order_by("date")
        votes = EventDateVotes.objects.filter(date__event=next_event).order_by("voter_id", "date")

        unique_voters = list(set(map(lambda v: v.voter, votes)))
        vote_map = {}
        for voter in unique_voters:
            vote_map[voter] = {date.date.isoformat(): None for date in dates}

        for vote in votes:
            voter = vote.voter
            v_date = vote.date.date.isoformat()
            if voter in vote_map and v_date in vote_map[voter]:
                vote_map[voter][v_date] = vote.available

        return render(request, 'homepage/events.html', {'next_event': next_event, "dates": dates, 'votes': vote_map})
    else:
        return HttpResponseRedirect(reverse("index"))


def voting(request: HttpRequest) -> django.http.HttpResponse:
    request.session.clear_expired()

    # Proxy use is forbidden
    if request.META.get("X-Forwarded-For"):
        raise ProxyUsageDetected()

    if request.method != "POST":
        return HttpResponseRedirect(reverse("events"))

    # Check rate limit
    ip = request.META.get("REMOTE_ADDR")
    cache_key = f"voting_block_{ip}"
    rate_cache: django.core.cache.BaseCache = cache
    if ip not in rate_cache:
        rate_cache.add(cache_key, 0, django_settings.IP_RATE_LIMIT_TIME)
    rate_cache.incr(cache_key)

    if rate_cache.get(cache_key) > django_settings.IP_RATE_LIMIT_COUNT:
        raise RateLimitHit()

    # check params
    if not request.POST["name"]:
        return HttpResponseRedirect(reverse("events"))

    name = request.POST["name"]
    modify_key = request.POST["modifyKey"] or ""

    request.session["name"] = name
    request.session["modifyKey"] = modify_key

    # handle delete
    if request.POST["deleteClicked"] == "1":
        VotingUser.objects.filter(name=name, modify_key=modify_key).delete()
        return HttpResponseRedirect(reverse("events"))

    # handle normal voting
    user, _ = VotingUser.objects.get_or_create(name=name, modify_key=modify_key)
    event_dates = EventDate.objects.filter(event__active=True).order_by("date")

    for date in event_dates:
        available = date.date.isoformat() in request.POST
        EventDateVotes.objects.update_or_create(voter=user, date=date, defaults={"available": available})

    return HttpResponseRedirect(reverse("events"))