Implement HTMX support for user collections display and refactor rendering logic

atlas/views.py

@@ -1131,15 +1131,25 @@ def user_collections(request):
     # Finished (completed)
     finished_qs = CaseCollection.objects.filter(pk__in=list(finished_ids)).order_by("name")
 
-    return render(
-        request,
-        "atlas/user_collections.html",
-        {
-            "available_collections": available_qs,
-            "in_progress_collections": in_progress_qs,
-            "finished_collections": finished_qs,
-        },
-    )
+    context = {
+        "available_collections": available_qs,
+        "in_progress_collections": in_progress_qs,
+        "finished_collections": finished_qs,
+    }
+
+    # If called via HTMX return a small fragment suitable for swapping
+    # into the index page. Otherwise render the full page.
+    is_htmx = getattr(request, "htmx", False) or request.headers.get("HX-Request", "").lower() == "true"
+    if is_htmx:
+        html = render_to_string("atlas/partials/_user_collections.html", context, request=request)
+        return HttpResponse(html)
+
+    return render(request, "atlas/user_collections.html", context)
+
+
+    # Note: keep the above full-page render for normal requests. If this
+    # endpoint is called by HTMX we prefer returning a small fragment so it
+    # can be swapped into the index page without duplicating layout.
 
 @login_required
 def collection_options(request):