from django.contrib.admin.views.decorators import staff_member_required
from django.shortcuts import redirect, get_object_or_404
from django.db.models.functions import TruncDate
from django.db.models import Count
from django.views import generic
from django.conf import settings
from django.urls import reverse
from django.http import Http404
from .models import Source, Entry
from .forms import SearchForm
import datetime


def _get_dates():
    now = datetime.date.today()
    start_date = now - datetime.timedelta(
        days=settings.KHAGANAT_LOGS_MAX_DAYS
    )
    end_date = now - datetime.timedelta(
        days=settings.KHAGANAT_LOGS_MIN_DAYS - 1
    )
    return (now, start_date, end_date)


def _switch_hidden(request, obj, pk):
    e = get_object_or_404(obj, pk=pk)
    e.hidden = not e.hidden
    e.save()

    next_page = request.GET.get('next', '')
    if next_page == '':
        next_page = reverse('log_index')
    return redirect(next_page)


@staff_member_required
def switch_source(request, pk):
    return _switch_hidden(request, Source, pk)


@staff_member_required
def switch_entry(request, pk):
    return _switch_hidden(request, Entry, pk)


def search_view(request):
    if request.method == 'POST':
        form = SearchForm(request.POST)
        if form.is_valid():
            date = form.cleaned_data['date']
            return redirect(reverse('log_day', kwargs={
                'source': form.cleaned_data['source'],
                'year': date.year,
                'month': date.month,
                'day': date.day,
            }))
    raise Http404('No search parameters.')


class IndexView(generic.ListView):
    template_name = 'logs/index.html'
    context_object_name = 'sources'

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context['form'] = SearchForm()
        return context

    def get_queryset(self):
        now, start_date, end_date = _get_dates()
        out = []
        qs = Entry.objects.all()

        if not self.request.user.is_staff:
            qs = qs.filter(
                hidden=False,
                source__hidden=False,
                created__range=(start_date, end_date)
            )
        qs = qs.values(
            'source', 'source__name', 'source__slug',
            'source__id', 'source__hidden'
        ).annotate(
            nb=Count('id')
        )

        for src in qs:
            src['stats'] = Entry.objects.filter(
                hidden=False,
                source=src['source'],
                created__range=(start_date, end_date)
            ).annotate(
                date=TruncDate('created')
            ).values('date').annotate(nb=Count('date')).order_by('-date')
            out.append(src)

        return out


class EntriesView(generic.ListView):
    context_object_name = 'entries'
    template_name = 'logs/entries.html'
    allow_empty = False

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context['date'] = datetime.date(
            self.kwargs['year'],
            self.kwargs['month'],
            self.kwargs['day']
        )
        context['source_channel'] = Source.objects.get(
            slug=self.kwargs['source']
        )
        if isinstance(context['source_channel'], tuple):
            context['source_channel'] = context['source_channel'][0]
        return context

    def get_queryset(self):
        is_staff = self.request.user.is_staff
        dt = datetime.date(
            self.kwargs['year'],
            self.kwargs['month'],
            self.kwargs['day']
        )
        now = datetime.date.today()
        out_of_bounds = any((
            (now - dt).days > settings.KHAGANAT_LOGS_MAX_DAYS,
            (now - dt).days < settings.KHAGANAT_LOGS_MIN_DAYS,
        ))
        if out_of_bounds and not is_staff:
            return Entry.objects.none()
        src = Source.objects.get(slug=self.kwargs['source'])
        if src is None:
            return Entry.objects.none()
        if src.hidden and not is_staff:
            return Entry.objects.none()
        qs = Entry.objects.filter(
            source=src,
            created__year=dt.year,
            created__month=dt.month,
            created__day=dt.day
        )
        if not is_staff:
            qs = qs.filter(hidden=False)
        return qs.order_by('created')