import typing

from django.contrib.auth.mixins import LoginRequiredMixin
from django.utils import timezone
from django.views.generic import CreateView, DetailView, ListView, UpdateView

from people import forms, models


class OrganisationCreateView(LoginRequiredMixin, CreateView):
    """View to create a new instance of :class:`Organisation`."""
    model = models.Organisation
    template_name = 'people/organisation/create.html'
    form_class = forms.OrganisationForm


class OrganisationListView(LoginRequiredMixin, ListView):
    """View displaying a list of :class:`organisation` objects."""
    model = models.Organisation
    template_name = 'people/organisation/list.html'

    def get_context_data(self,
                         **kwargs: typing.Any) -> typing.Dict[str, typing.Any]:
        context = super().get_context_data(**kwargs)

        context['existing_relationships'] = set(
            self.request.user.person.organisation_relationship_targets.
            values_list('pk', flat=True))

        return context


class OrganisationDetailView(LoginRequiredMixin, DetailView):
    """View displaying details of a :class:`Organisation`."""
    model = models.Organisation
    context_object_name = 'organisation'
    template_name = 'people/organisation/detail.html'

    def get_context_data(self,
                         **kwargs: typing.Any) -> typing.Dict[str, typing.Any]:
        """Add map marker to context."""
        context = super().get_context_data(**kwargs)

        answerset = self.object.current_answers
        context['answer_set'] = answerset
        context['map_markers'] = [{
            'name': self.object.name,
            'lat': getattr(answerset, 'latitude', None),
            'lng': getattr(answerset, 'longitude', None),
        }]

        return context


class OrganisationUpdateView(LoginRequiredMixin, UpdateView):
    """View for updating a :class:`Organisation` record."""
    model = models.Organisation
    context_object_name = 'organisation'
    template_name = 'people/organisation/update.html'
    form_class = forms.OrganisationAnswerSetForm

    def get_context_data(self,
                         **kwargs: typing.Any) -> typing.Dict[str, typing.Any]:
        """Add map marker to context."""
        context = super().get_context_data(**kwargs)

        answerset = self.object.current_answers
        context['map_markers'] = [{
            'name': self.object.name,
            'lat': getattr(answerset, 'latitude', None),
            'lng': getattr(answerset, 'longitude', None),
        }]

        return context

    def get_initial(self) -> typing.Dict[str, typing.Any]:
        try:
            previous_answers = self.object.current_answers.as_dict()

        except AttributeError:
            previous_answers = {}

        previous_answers.update({
            'organisation_id': self.object.id,
        })

        return previous_answers

    def get_form_kwargs(self) -> typing.Dict[str, typing.Any]:
        """Remove instance from form kwargs as it's an Organisation, but expects an OrganisationAnswerSet."""
        kwargs = super().get_form_kwargs()
        kwargs.pop('instance')

        return kwargs

    def form_valid(self, form):
        """Mark any previous answer sets as replaced."""
        response = super().form_valid(form)
        now_date = timezone.now().date()

        # Saving the form made self.object an OrganisationAnswerSet - so go up, then back down
        # Shouldn't be more than one after initial updates after migration
        for answer_set in self.object.organisation.answer_sets.exclude(
                pk=self.object.pk):
            answer_set.replaced_timestamp = now_date
            answer_set.save()

        return response