# lingo - payment and billing system
# Copyright (C) 2022  Entr'ouvert
#
# This program is free software: you can redistribute it and/or modify it
# under the terms of the GNU Affero General Public License as published
# by the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import collections
import datetime
import json

from django.contrib import messages
from django.db import transaction
from django.http import HttpResponse
from django.shortcuts import get_object_or_404
from django.urls import reverse, reverse_lazy
from django.utils.translation import ugettext_lazy as _
from django.utils.translation import ungettext
from django.views.generic import (
    CreateView,
    DeleteView,
    DetailView,
    FormView,
    ListView,
    TemplateView,
    UpdateView,
)

from lingo.agendas.models import Agenda
from lingo.invoicing.forms import CampaignForm, PoolForm
from lingo.invoicing.models import (
    Campaign,
    DraftInvoice,
    DraftInvoiceLine,
    InvoiceLine,
    Pool,
    Regie,
    RegieImportError,
)
from lingo.invoicing.utils import generate_invoices
from lingo.pricing.forms import ImportForm


def import_regies(data):
    results = collections.defaultdict(list)
    with transaction.atomic():
        regies = data.get('regies', [])
        for regie in regies:
            created, regie_obj = Regie.import_json(regie)
            if created:
                results['created'].append(regie_obj)
            else:
                results['updated'].append(regie_obj)
    return results


class HomeView(TemplateView):
    template_name = 'lingo/invoicing/manager_home.html'


home = HomeView.as_view()


class RegiesListView(ListView):
    template_name = 'lingo/invoicing/manager_regie_list.html'
    model = Regie


regies_list = RegiesListView.as_view()


class RegieAddView(CreateView):
    template_name = 'lingo/invoicing/manager_regie_form.html'
    model = Regie
    fields = ['label', 'description', 'cashier_role']

    def get_success_url(self):
        return reverse('lingo-manager-invoicing-regie-detail', args=[self.object.pk])


regie_add = RegieAddView.as_view()


class RegieDetailView(DetailView):
    template_name = 'lingo/invoicing/manager_regie_detail.html'
    model = Regie

    def get_context_data(self, **kwargs):
        kwargs['regie'] = self.object
        kwargs['agendas'] = Agenda.objects.filter(regie=self.object)
        return super().get_context_data(**kwargs)


regie_detail = RegieDetailView.as_view()


class RegieEditView(UpdateView):
    template_name = 'lingo/invoicing/manager_regie_form.html'
    model = Regie
    fields = ['label', 'description', 'cashier_role']

    def get_success_url(self):
        return reverse('lingo-manager-invoicing-regie-detail', args=[self.object.pk])


regie_edit = RegieEditView.as_view()


class RegieDeleteView(DeleteView):
    template_name = 'lingo/manager_confirm_delete.html'
    model = Regie

    def get_success_url(self):
        return reverse('lingo-manager-invoicing-regie-list')


regie_delete = RegieDeleteView.as_view()


class RegiesExportView(ListView):
    model = Regie

    def get(self, request, *args, **kwargs):
        response = HttpResponse(content_type='application/json')
        today = datetime.date.today()
        attachment = 'attachment; filename="export_regies_{}.json"'.format(today.strftime('%Y%m%d'))
        response['Content-Disposition'] = attachment
        json.dump({'regies': [regie.export_json() for regie in self.get_queryset()]}, response, indent=2)
        return response


regies_export = RegiesExportView.as_view()


class RegiesImportView(FormView):
    form_class = ImportForm
    template_name = 'lingo/invoicing/manager_import.html'
    success_url = reverse_lazy('lingo-manager-invoicing-regie-list')

    def form_valid(self, form):
        try:
            config_json = json.loads(self.request.FILES['config_json'].read())
        except ValueError:
            form.add_error('config_json', _('File is not in the expected JSON format.'))
            return self.form_invalid(form)

        try:
            results = import_regies(config_json)
        except RegieImportError as exc:
            form.add_error('config_json', '%s' % exc)
            return self.form_invalid(form)

        import_messages = {
            'create': lambda x: ungettext(
                'A regie was created.',
                '%(count)d regies were created.',
                x,
            ),
            'update': lambda x: ungettext(
                'A regie was updated.',
                '%(count)d regie were updated.',
                x,
            ),
        }
        create_message = _('No regie created.')
        update_message = _('No regie updated.')
        created = len(results.get('created', []))
        updated = len(results.get('updated', []))
        if created:
            create_message = import_messages.get('create')(created) % {'count': created}
        if updated:
            update_message = import_messages.get('update')(updated) % {'count': updated}
        message = "%s %s" % (create_message, update_message)
        messages.info(self.request, message)

        return super().form_valid(form)


regies_import = RegiesImportView.as_view()


class CampaignListView(ListView):
    template_name = 'lingo/invoicing/manager_campaign_list.html'
    model = Campaign


campaign_list = CampaignListView.as_view()


class CampaignAddView(CreateView):
    template_name = 'lingo/invoicing/manager_campaign_form.html'
    model = Campaign
    form_class = CampaignForm

    def get_success_url(self):
        return reverse('lingo-manager-invoicing-campaign-detail', args=[self.object.pk])


campaign_add = CampaignAddView.as_view()


class CampaignDetailView(DetailView):
    template_name = 'lingo/invoicing/manager_campaign_detail.html'
    model = Campaign

    def get_context_data(self, **kwargs):
        kwargs['pools'] = self.object.pool_set.order_by('created_at')
        kwargs['has_real_pool'] = any(not p.draft for p in kwargs['pools'])
        return super().get_context_data(**kwargs)


campaign_detail = CampaignDetailView.as_view()


class CampaignEditView(UpdateView):
    template_name = 'lingo/invoicing/manager_campaign_form.html'
    model = Campaign
    form_class = CampaignForm

    def get_queryset(self):
        return super().get_queryset().exclude(pool__draft=False)

    def get_success_url(self):
        return reverse('lingo-manager-invoicing-campaign-detail', args=[self.object.pk])


campaign_edit = CampaignEditView.as_view()


class CampaignDeleteView(DeleteView):
    template_name = 'lingo/manager_confirm_delete.html'
    model = Campaign

    def get_queryset(self):
        return super().get_queryset().exclude(pool__draft=False)

    def delete(self, request, *args, **kwargs):
        self.object = self.get_object()
        DraftInvoiceLine.objects.filter(pool__campaign=self.object).delete()
        DraftInvoice.objects.filter(pool__campaign=self.object).delete()
        Pool.objects.filter(campaign=self.object).delete()
        return super().delete(request, *args, **kwargs)

    def get_success_url(self):
        return reverse('lingo-manager-invoicing-campaign-list')


campaign_delete = CampaignDeleteView.as_view()


class PoolDetailView(DetailView):
    template_name = 'lingo/invoicing/manager_pool_detail.html'
    model = Pool
    pk_url_kwarg = 'pool_pk'

    def dispatch(self, request, *args, **kwargs):
        self.campaign = get_object_or_404(Campaign, pk=kwargs['pk'])
        return super().dispatch(request, *args, **kwargs)

    def get_queryset(self):
        return self.campaign.pool_set.all()

    def get_context_data(self, **kwargs):
        kwargs['object'] = self.campaign
        kwargs['pool'] = self.object
        line_model = InvoiceLine
        if self.object.draft:
            line_model = DraftInvoiceLine
        kwargs['lines'] = line_model.objects.filter(pool=self.object)
        return super().get_context_data(**kwargs)


pool_detail = PoolDetailView.as_view()


class PoolAddView(FormView):
    template_name = 'lingo/invoicing/manager_pool_form.html'
    form_class = PoolForm

    def dispatch(self, request, *args, **kwargs):
        self.object = get_object_or_404(Campaign.objects.exclude(pool__draft=False), pk=kwargs['pk'])
        return super().dispatch(request, *args, **kwargs)

    def get_form_kwargs(self):
        kwargs = super().get_form_kwargs()
        kwargs['campaign'] = self.object
        return kwargs

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

    def form_valid(self, form):
        generate_invoices(campaign=self.object, draft=form.cleaned_data['draft'])
        return super().form_valid(form)

    def get_success_url(self):
        return '%s#open:pools' % reverse('lingo-manager-invoicing-campaign-detail', args=[self.object.pk])


pool_add = PoolAddView.as_view()


class PoolDeleteView(DeleteView):
    template_name = 'lingo/manager_confirm_delete.html'
    model = Pool
    pk_url_kwarg = 'pool_pk'

    def dispatch(self, request, *args, **kwargs):
        self.campaign = get_object_or_404(Campaign.objects.exclude(pool__draft=False), pk=kwargs['pk'])
        return super().dispatch(request, *args, **kwargs)

    def get_queryset(self):
        return self.campaign.pool_set.filter(draft=True)

    def delete(self, request, *args, **kwargs):
        self.object = self.get_object()
        DraftInvoiceLine.objects.filter(pool=self.object).delete()
        DraftInvoice.objects.filter(pool=self.object).delete()
        return super().delete(request, *args, **kwargs)

    def get_success_url(self):
        return '%s#open:pools' % reverse('lingo-manager-invoicing-campaign-detail', args=[self.campaign.pk])


pool_delete = PoolDeleteView.as_view()