Update app.py

app.py

@@ -248,6 +248,32 @@ import unicodedata
 from collections import Counter
 from difflib import SequenceMatcher
 import math
+# Stage <-> Source mapping
+STAGE_TO_SOURCE = {
+    "onboarding": "onboarding_responses",
+    "week_2": "week_2_responses",
+    "week_3": "week_3_responses",
+    "closing": "closing_responses",  # future-proof
+}
+SOURCE_TO_STAGE = {v: k for k, v in STAGE_TO_SOURCE.items()}
+
+def _responses_for_student_stage(uri, db, responses_coll, student: str, stage: str) -> list[dict]:
+    """Return responses for a student at a stage (mapped to source) with non-empty answers."""
+    if not (uri and student and stage):
+        return []
+    src = STAGE_TO_SOURCE.get(stage)
+    if not src:
+        return []
+    try:
+        c = _client(uri)
+        docs = list(c[db][responses_coll].find(
+            {"student": student, "source": src},
+            {"_id": 0, "answer": 1, "skills": 1}
+        ))
+        # keep only responses with a non-empty answer
+        return [d for d in docs if (d.get("answer") or "").strip()]
+    except Exception:
+        return []
 
 def _normalize_quotes_spaces(s: str) -> str:
     if not s: