Add leave team button

apps/participation/views.py

@@ -2,6 +2,9 @@ from io import BytesIO
 import os
 from zipfile import ZipFile
 
+from django.shortcuts import redirect
+from django.views.generic.base import View, TemplateView
+
 from corres2math.lists import get_sympa_client
 from corres2math.views import AdminMixin
 from django.contrib.auth.mixins import LoginRequiredMixin
@@ -236,6 +239,29 @@ class TeamAuthorizationsView(LoginRequiredMixin, DetailView):
         return response
 
 
+class TeamLeaveView(LoginRequiredMixin, TemplateView):
+    template_name = "participation/team_leave.html"
+
+    def dispatch(self, request, *args, **kwargs):
+        if not request.user.is_authenticated:
+            return self.handle_no_permission()
+        if not request.user.registration.team:
+            raise PermissionDenied(_("You are not in a team."))
+        if request.user.registration.team.participation.valid is not None:
+            raise PermissionDenied(_("The team is already validated or the validation is pending."))
+        return super().dispatch(request, *args, **kwargs)
+
+    @transaction.atomic()
+    def post(self, request, *args, **kwargs):
+        team = request.user.registration.team
+        request.user.registration.team = None
+        request.user.registration.save()
+        get_sympa_client().unsubscribe(request.user.email, f"equipe-{team.trigram.lower()}", False)
+        if team.students.count() + team.coachs.count() == 0:
+            team.delete()
+        return redirect(reverse_lazy("index"))
+
+
 class MyParticipationDetailView(LoginRequiredMixin, RedirectView):
     def get_redirect_url(self, *args, **kwargs):
         user = self.request.user