guests: change unique constraints, send notification with access link on signup (#1651)

* guests: change unique constraints, send notification with access link on signup

* resend notification when signing up again

* filter guest participations by event

* change notification logic, add translations

* fix translations, lint

---------

Co-authored-by: Julian Baumann <julian.baumann@sap.com>

Author: jeriox

ephios/locale/de/LC_MESSAGES/django.po

@@ -7,7 +7,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: \n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2025-09-04 22:33+0200\n"
+"POT-Creation-Date: 2025-09-11 23:54+0200\n"
 "PO-Revision-Date: 2025-09-04 22:35+0200\n"
 "Last-Translator: Felix Rindt <felix@ephios.de>\n"
 "Language-Team: German <https://hosted.weblate.org/projects/ephios/ephios/de/"
@@ -1688,6 +1688,7 @@ msgstr ""
 #: ephios/core/services/notifications/types.py:624
 #: ephios/core/templates/core/mails/new_event.html:35
 #: ephios/core/templates/core/userprofile_workinghours.html:47
+#: ephios/plugins/guests/notifications.py:33
 msgid "View event"
 msgstr "Veranstaltung anzeigen"
 
@@ -4468,6 +4469,22 @@ msgstr "Gastteilnehmahme"
 msgid "guest participations"
 msgstr "Gastteilnehmahmen"
 
+#: ephios/plugins/guests/notifications.py:12
+msgid "A guest user has signed up"
+msgstr "Ein Gast hat sich angemeldet"
+
+#: ephios/plugins/guests/notifications.py:21
+#, python-brace-format
+msgid "You have signed up for {event}"
+msgstr "Sie haben sich für {event} angemeldet."
+
+#: ephios/plugins/guests/notifications.py:26
+#, python-brace-format
+msgid ""
+"You have signed up for {event} at {platform}. You can use the link below to "
+"make changes to your participation."
+msgstr "Sie haben sich für {event} bei {platform} angemeldet. Sie können den Link unten benutzen, um Ihre Teilnahme anzupassen."
+
 #: ephios/plugins/guests/templates/guests/guestuser_form.html:7
 #: ephios/plugins/guests/templates/guests/guestuser_form.html:16
 msgid "Register as guest"
@@ -4477,19 +4494,21 @@ msgstr "Als Gast registrieren"
 msgid "Continue"
 msgstr "Weiter"
 
-#: ephios/plugins/guests/views.py:54
+#: ephios/plugins/guests/views.py:55
 msgid "Log out to register as guest."
 msgstr "Melden Sie sich ab, um sich als Gast zu registrieren."
 
-#: ephios/plugins/guests/views.py:78
-msgid "You already registered as a guest for this event."
-msgstr "Sie sind bereits als Gast für diese Veranstaltung registriert."
+#: ephios/plugins/guests/views.py:80
+msgid ""
+"You already registered as a guest for this event. We sent you an email with "
+"a link that you can use to change your participation."
+msgstr "Sie sind bereits als Gast für diese Veranstaltung registriert. Wir haben Ihnen eine E-Mail mit einem Link geschickt, über den Sie Ihre Teilnahme ändern können."
 
-#: ephios/plugins/guests/views.py:81
+#: ephios/plugins/guests/views.py:98
 msgid "Save the URL of this page to access this site later."
 msgstr "Speichern Sie die URL dieser Seite, um später zurückzukehren."
 
-#: ephios/plugins/guests/views.py:90
+#: ephios/plugins/guests/views.py:107
 msgid "Log out to view the guest version of this page."
 msgstr "Melden Sie sich ab, um die Besucheransicht dieser Seite zu sehen."
 
@@ -5082,7 +5101,7 @@ msgstr ""
 msgid "Saved questionnaire answers"
 msgstr "Gespeicherte Antworten"
 
-#: ephios/plugins/questionnaires/templates/questionnaires/savedanswer_list.html:29
+#: ephios/plugins/questionnaires/templates/questionnaires/savedanswer_list.html:26
 msgid "not used anymore"
 msgstr "nicht mehr verwendet"
 
@@ -5357,6 +5376,9 @@ msgstr "Passwort erfolgreich zurückgesetzt"
 msgid "Please check your mailbox for further instructions."
 msgstr "Bitte prüfen Sie Ihren E-Mail-Posteingang für weitere Anweisungen."
 
+#~ msgid "You already registered as a guest for this event."
+#~ msgstr "Sie sind bereits als Gast für diese Veranstaltung registriert."
+
 #, python-brace-format
 #~ msgid ""
 #~ "You are already confirmed for the following other shifts: {shifts}. "

ephios/plugins/guests/migrations/0007_alter_guestuser_unique_together.py

@@ -0,0 +1,47 @@
+# Generated by Django 5.2.6 on 2025-09-11 20:06
+
+from django.db import migrations
+from django.db.models import Count
+
+from ephios.core.models.events import PlaceholderParticipation
+from ephios.plugins.guests.models import GuestParticipation
+
+
+def deduplicate_guest_participations(apps, schema_editor):
+    GuestUser = apps.get_model("guests", "GuestUser")
+    for duplicate_guest in (
+        GuestUser.objects.values("email", "event_id").annotate(Count("id")).filter(id__count__gt=1)
+    ):
+        for participation in GuestParticipation.objects.filter(
+            guest_user__email=duplicate_guest["email"],
+            guest_user__event_id=duplicate_guest["event_id"],
+        ):
+            PlaceholderParticipation.objects.create(
+                display_name=participation.guest_user.display_name,
+                shift=participation.shift,
+                state=participation.state,
+                structure_data=participation.structure_data,
+                finished=participation.finished,
+                individual_start_time=participation.individual_start_time,
+                individual_end_time=participation.individual_end_time,
+            )
+            participation.delete()
+        GuestUser.objects.filter(
+            email=duplicate_guest["email"], event_id=duplicate_guest["event_id"]
+        ).delete()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("core", "0038_eventtype_default_description"),
+        ("guests", "0006_alter_guestuser_qualifications"),
+    ]
+
+    operations = [
+        migrations.RunPython(deduplicate_guest_participations),
+        migrations.AlterUniqueTogether(
+            name="guestuser",
+            unique_together={("event", "email")},
+        ),
+    ]

ephios/plugins/guests/models.py

@@ -71,7 +71,7 @@ def __str__(self):
 
     class Meta:
         # there might be two people using the same email *sigh*
-        unique_together = [["event", "email", "display_name"]]
+        unique_together = [["event", "email"]]
         verbose_name = _("guest user")
         verbose_name_plural = _("guest users")
 

ephios/plugins/guests/notifications.py

@@ -0,0 +1,40 @@
+from urllib.parse import urljoin
+
+from django.utils.translation import gettext_lazy as _
+from dynamic_preferences.registries import global_preferences_registry
+
+from ephios.core.dynamic import dynamic_settings
+from ephios.core.models import Notification
+from ephios.core.services.notifications.types import AbstractNotificationHandler
+
+
+class GuestUserSignupNotification(AbstractNotificationHandler):
+    slug = "guests_signup"
+    title = _("A guest user has signed up")
+    unsubscribe_allowed = False
+
+    @classmethod
+    def send(cls, **kwargs):
+        Notification.objects.create(slug=cls.slug, data=kwargs)
+
+    @classmethod
+    def get_subject(cls, notification):
+        return _("You have signed up for {event}").format(event=notification.data["event_title"])
+
+    @classmethod
+    def get_body(cls, notification):
+        return _(
+            "You have signed up for {event} at {platform}. You can use the link below to make changes to your participation."
+        ).format(
+            event=notification.data["event_title"],
+            platform=global_preferences_registry.manager()["general__organization_name"],
+        )
+
+    @classmethod
+    def get_actions(cls, notification):
+        return [
+            (
+                str(_("View event")),
+                urljoin(dynamic_settings.SITE_URL, notification.data["event_url"]),
+            )
+        ]

ephios/plugins/guests/signals.py

@@ -1,8 +1,9 @@
 from django.dispatch import receiver
 
-from ephios.core.signals import event_forms, participant_from_request
+from ephios.core.signals import event_forms, participant_from_request, register_notification_types
 from ephios.plugins.guests.forms import EventAllowGuestsForm
 from ephios.plugins.guests.models import GuestUser
+from ephios.plugins.guests.notifications import GuestUserSignupNotification
 
 
 @receiver(
@@ -23,3 +24,8 @@ def guest_participant_from_request(sender, request, **kwargs):
 )
 def guests_event_forms(sender, event, request, **kwargs):
     return [EventAllowGuestsForm(request.POST or None, event=event, request=request)]
+
+
+@receiver(register_notification_types, dispatch_uid="guests.signals.guests_notification_types")
+def register_guests_notification_types(sender, **kwargs):
+    return [GuestUserSignupNotification]

ephios/plugins/guests/views.py

@@ -15,6 +15,7 @@
 from ephios.extra.auth import access_exempt
 from ephios.extra.widgets import CustomDateInput
 from ephios.plugins.guests.models import EventGuestShare, GuestUser
+from ephios.plugins.guests.notifications import GuestUserSignupNotification
 
 
 @access_exempt
@@ -75,11 +76,27 @@ def form_valid(self, form):
             # unique_together constraint not passed
             form.add_error(
                 None,
-                _("You already registered as a guest for this event."),
+                _(
+                    "You already registered as a guest for this event. We sent you an email with a link that you can use to change your participation."
+                ),
+            )
+            guest = GuestUser.objects.get(email=form.cleaned_data["email"], event=self.event)
+            GuestUserSignupNotification.send(
+                event_title=self.event.title,
+                guest_name=guest.display_name,
+                email=guest.email,
+                event_url=guest.as_participant().reverse_event_detail(self.event),
             )
             return self.form_invalid(form)
+        event_url = guest.as_participant().reverse_event_detail(self.event)
+        GuestUserSignupNotification.send(
+            event_title=self.event.title,
+            guest_name=guest.display_name,
+            email=guest.email,
+            event_url=event_url,
+        )
         messages.info(self.request, _("Save the URL of this page to access this site later."))
-        return redirect(guest.as_participant().reverse_event_detail(self.event))
+        return redirect(event_url)
 
 
 class GuestEventDetailView(RedirectAuthenticatedUserMixin, DetailView):