from django.contrib import messages
from django.contrib.auth.decorators import login_required
from django.contrib.auth.views import redirect_to_login
from django.core.exceptions import PermissionDenied
from django.shortcuts import get_object_or_404, render
from django.utils import timezone
from django.views.decorators.http import require_POST
from djconfig import config

from spirit.core import utils
from spirit.core.utils.http import safe_redirect
from spirit.core.utils.paginator import yt_paginate

from .forms import PollVoteManyForm
from .models import CommentPoll, CommentPollChoice, CommentPollVote


@login_required
@require_POST
def close_or_open(request, pk, close=True):
    # todo: moderators should be able to close it
    poll = get_object_or_404(CommentPoll, pk=pk, comment__user=request.user)

    if close:
        close_at = timezone.now()
    else:
        close_at = None

    (CommentPoll.objects.filter(pk=poll.pk).update(close_at=close_at))

    return safe_redirect(request, "next", poll.get_absolute_url())


@require_POST
def vote(request, pk):
    # TODO: check if user has access to this topic/poll
    poll = get_object_or_404(CommentPoll.objects.unremoved(), pk=pk)

    if not request.user.is_authenticated:
        return redirect_to_login(next=poll.get_absolute_url())

    form = PollVoteManyForm(user=request.user, poll=poll, data=request.POST)

    if form.is_valid():
        CommentPollChoice.decrease_vote_count(poll=poll, voter=request.user)
        form.save_m2m()
        CommentPollChoice.increase_vote_count(poll=poll, voter=request.user)
        return safe_redirect(request, "next", poll.get_absolute_url(), method="POST")

    messages.error(request, utils.render_form_errors(form))
    return safe_redirect(request, "next", poll.get_absolute_url(), method="POST")


@login_required
def voters(request, pk):
    # TODO: check if user has access to this topic/poll
    choice = get_object_or_404(
        CommentPollChoice.objects.unremoved().select_related("poll"), pk=pk
    )

    if not choice.poll.can_show_results:
        raise PermissionDenied

    choice_votes = (
        CommentPollVote.objects.unremoved()
        .for_choice(choice=choice)
        .select_related("voter__st")
    )

    choice_votes = yt_paginate(
        choice_votes,
        per_page=config.topics_per_page,
        page_number=request.GET.get("page", 1),
    )

    context = {"choice": choice, "votes": choice_votes}

    return render(request, "spirit/comment/poll/voters.html", context)
