from django.template import RequestContext
from django.shortcuts import render
from django.views import View
from django.views.generic.base import TemplateView
from django.conf import settings
from django.http import Http404
from django.http import HttpResponse
from django.http import HttpResponseRedirect
from django.db.models import Case, When, Value, IntegerField, Count, F

from LandingPage.models import User
from LandingPage.models import Show
from LandingPage.models import Season
from LandingPage.models import Episode
from LandingPage.models import Submission, SubmissionVote

from . import forms

import datetime

# Create your views here.

# Index page of a show
class IndexView(TemplateView):
    template_name = "show.html"

    def get_context_data(self, abbreviation, **kwargs):
        ctx = super().get_context_data()

        # Get show by abbreviation, add episode count to the show and return only the first object
        show = Show.objects.filter(abbr=abbreviation).first()

        # 404
        if not show:
            raise Http404("Show does not exist")

        # Get all seasons of the show and annotate episode counts onto them
        seasons = show.seasons.all()

        # Add fields to context
        ctx['show'] = show
        ctx['seasons'] = seasons

        return ctx

# Episodes page of a show
class EpisodeView(TemplateView):
    template_name = "episode.html"

    def get_context_data(self, abbreviation, season, episode, **kwargs):
        ctx = super().get_context_data()

        # Get show by abbreviation
        show = Show.objects.filter(abbr=abbreviation).first()

        # Get episode by season and episode number
        episode = Episode.objects.filter(show=show,season__number=season,episode=episode).first()

        # 404's
        if not show:
            raise Http404("Show does not exist")
        
        if not episode:
            raise Http404("Episode does not exist")

        # I acknowledge that this is a mess. A functional mess. But a mess nonetheless. Hey, that rhymed!
        submissions = episode.submissions.annotate(
            positives=Count(
                Case(
                    When(
                        votes__positive=True,
                        then=Value(1)
                        )
                    )
                ),
            negatives=Count('votes') - F('positives'),
            score=F('positives') - F('negatives')
        ).order_by('-score')

        # Add fields to context
        ctx['show'] = show
        ctx['episode'] = episode
        ctx['submissions'] = submissions

        return ctx

# Submission form GET and POST
def SubmissionForm(req, abbreviation, season, episode):
    show = Show.objects.get(abbr=abbreviation)
    episode = Episode.objects.filter(show=show,season__number=season,episode=episode).first()

    # Check for login status
    if not 'user_id' in req.session:
        return HttpResponse('<h1>Error</h1><p>You need to be logged in to submit. Please <a href=/login>log in</a></p>', status=400)

    user = User.objects.get(user_id=req.session['user_id'])

    # 404's
    if not show:
        raise Http404("Show does not exist")

    if not episode:
        raise Http404("Episode does not exist")

    form = forms.SubmissionForm()

    # Request context
    ctx = {
        'form': form,
        'show': show,
        'episode': episode
    }

    # Handle POST
    if req.method == 'POST':
        form = forms.SubmissionForm(req.POST)
        ctx['form'] = form

        if form.is_valid():
            form_data = form.cleaned_data

            # Check if the URL has already been submitted
            if Submission.objects.filter(episode=episode,url=form_data['url']).count() > 0:
                ctx['error'] = 'This URL has already been submitted!'
                return render(req, "submit.html", ctx)

            # Check if there has been a submission by this user for this episode within the last 24 hours
            if Submission.objects.filter(user=user,episode=episode,timestamp__gte=datetime.datetime.now() - datetime.timedelta(hours=24)).count() > 0:
                ctx['error'] = 'You can only submit one link for an episode in 24 hours!'
                return render(req, "submit.html", ctx)

            # Have to do this because you can't add fields to a form
            # If you know a better way of doing this, be my guest
            new_submission = form.save(commit=False)
            new_submission.user = user
            new_submission.episode = episode
            new_submission.save()

            return HttpResponseRedirect('/show/%s/episode/%d/%d'%(abbreviation, episode.season.number, episode.episode))
        else:
            ctx['error'] = 'Invalid fields!'

    return render(req, "submit.html", ctx)

# Vote request
# /show/{{abbr}}/vote/{{submission id}}/{{positive == 1}}
class SubmissionVoteSubmit(View):
    def post (self, req, abbreviation, subid, positive):
        # Convert positive parameter into a boolean
        pos_bool = int(positive) == 1

        # Check for login status
        if not 'user_id' in req.session:
            return HttpResponse('<h1>Error</h1><p>You need to be logged in to vote.  Please <a href=/login>log in</a></p>', status=400)

        user = User.objects.get(user_id=req.session['user_id'])

        # Get the submission from the database
        submission = Submission.objects.filter(id=subid).first()

        # 404
        if not submission:
            raise Http404("Submission does not exist")

        # Prevent voting for own submission
        if submission.user == user:
            return HttpResponse('<h1>Error</h1><p>You cannot vote for your own submission.</p>', status=400)

        # Allow changing a vote from positive to negative or vice-versa. Delete vote if its a re-vote
        vote = submission.votes.filter(user=user,submission__id=submission.id).first()
        if vote:
            if not vote.positive == pos_bool:
                vote.positive = pos_bool
                vote.save()
            else:
                vote.delete()
        else:
            new_vote = SubmissionVote(
                    user=user,
                    submission=submission,
                    positive=pos_bool
                )
            new_vote.save()

        return HttpResponseRedirect('/show/%s/episode/%d/%d'%(abbreviation, submission.episode.season.number, submission.episode.episode))