combo/combo/apps/lingo/views.py

# lingo - basket and payment system
# Copyright (C) 2015  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/>.

from decimal import Decimal
import json

from django.contrib.auth.models import User
from django.core.urlresolvers import reverse
from django.http import HttpResponse, HttpResponseRedirect
from django.template.response import TemplateResponse
from django.utils import timezone
from django.views.decorators.csrf import csrf_exempt
from django.views.generic import View, ListView

import eopayment

from .models import Regie, BasketItem, Transaction

class RegiesApiView(ListView):
    model = Regie

    def get(self, request, *args, **kwargs):
        response = HttpResponse(content_type='application/json')
        data = {'data': [x.as_api_dict() for x in self.get_queryset()]}
        json_str = json.dumps(data)
        if 'jsonpCallback' in request.GET:
            json_str = '%s(%s);' % (request.GET['jsonpCallback'], json_str)
        response.write(json_str)
        return response


class AddBasketItemApiView(View):
    http_method_names = ['post', 'options']

    @csrf_exempt
    def dispatch(self, *args, **kwargs):
        return super(AddBasketItemApiView, self).dispatch(*args, **kwargs)

    def post(self, request, *args, **kwargs):
        # XXX: check request signature

        request_body = json.loads(self.request.body)

        item = BasketItem()
        item.amount = Decimal(request.GET.get('amount'))

        try:
            if request.GET.get('NameId'):
                user = User.objects.get(username=request.GET.get('NameId'))
            elif request.GET.get('email'):
                user = User.objects.get(email=request.GET.get('email'))
            else:
                raise Exception('no user specified')
        except User.DoesNotExist:
            raise Exception('unknown user')

        item.user = user
        if request.GET.get('regie_id'):
            item.regie = Regie.objects.get(id=request.GET.get('regie_id'))
        else:
            # if there's no regie specified, use the first one we get from the
            # database...
            item.regie = Regie.objects.all()[0]

        item.subject = request_body.get('display_name')
        item.source_url = request_body.get('url')

        item.save()

        response = HttpResponse(content_type='application/json')
        response.write(json.dumps({'result': 'success'}))
        return response

class PayView(View):
    def post(self, request, *args, **kwargs):
        items = BasketItem.objects.filter(id__in=request.POST.getlist('item'))
        # XXX: check all items are going to the same regie

        transaction = Transaction()
        transaction.user = request.user
        transaction.save()
        transaction.items = items
        transaction.status = 0
        transaction.save()

        total_amount = sum([x.amount for x in items])

        regie = items[0].regie

        payment = eopayment.Payment(regie.service, regie.service_options)
        return_url = request.build_absolute_uri(
                reverse('lingo-callback', kwargs={'regie_pk': regie.id}))
        (order_id, kind, data) = payment.request(total_amount,
                next_url=request.build_absolute_uri('/'),
                accepturl=return_url,
                declineurl=return_url,
                exceptionurl=return_url,
                cancelurl=return_url)
        transaction.order_id = order_id
        transaction.save()

        # XXX: mark basket items as being processed (?)

        if kind == eopayment.URL:
            return HttpResponseRedirect(data)
        elif kind == eopayment.FORM:
            return TemplateResponse(request, 'lingo/payment_form.html', {'form': data})

        raise NotImplementedError()


class CallbackView(View):
    def get(self, request, *args, **kwargs):
        regie = Regie.objects.get(id=kwargs.get('regie_pk'))
        payment = eopayment.Payment(regie.service, regie.service_options)
        payment_response = payment.response(request.environ['QUERY_STRING'])
        if not payment_response.result == eopayment.CANCELLED:
            # cancellation are not signed...
            assert payment_response.signed is True

        transaction = Transaction.objects.get(order_id=payment_response.order_id)
        transaction.status = payment_response.result
        transaction.bank_data = payment_response.bank_data
        transaction.end_date = timezone.now()
        transaction.save()

        if payment_response.result != eopayment.PAID:
            return HttpResponseRedirect('/')

        for item in transaction.items.all():
            item.payment_date = transaction.end_date
            item.save()
            try:
                item.notify()
            except:
                # ignore errors, it will be retried later on if it fails
                pass
        return HttpResponseRedirect('/')