Add proper email notifications

apps/accounts/urls.py

@@ -0,0 +1,14 @@
+"""Local additions under `/accounts/`. Mounted in `hamprint/urls.py` BEFORE
+`include("allauth.urls")` so any path defined here wins; everything we
+don't claim falls through to allauth.
+"""
+
+from django.urls import path
+
+from . import views
+
+app_name = "accounts"
+
+urlpatterns = [
+    path("close/", views.close_account, name="close"),
+]

apps/accounts/views.py

@@ -1,3 +1,68 @@
-from django.shortcuts import render
+"""Local account views -- the ones allauth doesn't ship.
 
-# Create your views here.
+Today: just `close_account` ("permanently delete this user"). Logout is
+allauth's; we override its template, not its view.
+"""
+
+from __future__ import annotations
+
+from django.contrib import messages
+from django.contrib.auth import logout
+from django.contrib.auth.decorators import login_required
+from django.db import transaction
+from django.http import HttpResponseForbidden
+from django.shortcuts import redirect, render
+from django.views.decorators.http import require_http_methods
+
+from apps.submissions.models import Submission
+
+
+@login_required
+@require_http_methods(["GET", "POST"])
+def close_account(request):
+    """Permanently delete the signed-in user and all of their submissions.
+
+    GET   -> render a "are you sure?" confirmation page, showing how many of
+             their submissions will go with the user.
+    POST  -> delete the rows, log the user out, redirect to the dashboard.
+
+    Refuses staff users (`is_staff=True`): they'd be locking themselves
+    (and possibly the only operator) out of /admin/ with no recourse, so
+    that path requires another operator to remove the row via
+    /admin/auth/user/ instead.
+
+    Why delete the submissions too: `Submission.submitted_by` uses
+    `on_delete=SET_NULL`, but the `CheckConstraint` on the model requires
+    that EITHER `submitted_by` OR `guest_email` is non-null. OAuth-created
+    submissions have `guest_email=NULL`, so SET_NULL would violate the
+    constraint at delete time. Simpler + matches user expectation of
+    "delete my account": wipe the rows wholesale. The `post_delete` signal
+    in `apps/submissions/signals.py` unlinks the uploaded STLs at the
+    same time.
+    """
+    if request.user.is_staff:
+        return HttpResponseForbidden(
+            "Staff users cannot close their own account from here. "
+            "Ask another operator to remove the row via /admin/auth/user/."
+        )
+
+    if request.method == "POST":
+        user = request.user
+        username = user.get_username()
+        with transaction.atomic():
+            Submission.objects.filter(submitted_by=user).delete()
+            logout(request)
+            user.delete()
+        messages.info(
+            request,
+            f"Account {username} and all of your prints have been "
+            f"permanently deleted.",
+        )
+        return redirect("dashboard:index")
+
+    submission_count = Submission.objects.filter(submitted_by=request.user).count()
+    return render(
+        request,
+        "account/close.html",
+        {"submission_count": submission_count},
+    )