Fix spacer feedback specificity

Author: ShengkaiXu

evaluation_function/evaluation.py

@@ -109,6 +109,7 @@
     },
     "spacer": {
         "pass": "Good. The spacer setup looks correct.",
+        "none_detected": "No spacers were detected clearly. Please make sure both spacers are installed and clearly visible in the photo.",
         "short_missing": "The short spacer may be missing or not detected. Please check whether the short spacer is installed and retake the photo if needed.",
         "long_missing": "The long spacer may be missing or not detected. Please check whether the long spacer is installed and retake the photo if needed.",
         "count_fail": "A spacer may be missing or not detected. Please check whether both spacers are installed and retake the photo if needed.",
@@ -397,6 +398,8 @@ def _get_shaft_counts(out: Dict[str, Any]) -> Tuple[int, int, int]:
 
 def _get_spacer_counts(out: Dict[str, Any]) -> Tuple[int, int, int]:
     counts = out.get("spacer_counts", {}) if isinstance(out.get("spacer_counts"), dict) else {}
+    if not counts:
+        counts = out.get("counts", {}) if isinstance(out.get("counts"), dict) else {}
 
     n_long = _safe_int(counts.get("spacer_long", 0))
     n_short = _safe_int(counts.get("spacer_short", 0))
@@ -680,9 +683,18 @@ def advice_text() -> str:
         n_long, n_short, n_total = _get_spacer_counts(out)
         counts_dict = _get_counts_dict(out)
 
+        if "E_SPACER_SHORT_MISSING" in codes:
+            return False, MESSAGE_POLICY["spacer"]["short_missing"]
+
+        if "E_SPACER_LONG_MISSING" in codes:
+            return False, MESSAGE_POLICY["spacer"]["long_missing"]
+
+        if "E_SPACER_TYPE_CONFUSION" in codes:
+            return False, MESSAGE_POLICY["spacer"]["type_confusion"]
+
         if ("spacer_long" in counts_dict) or ("spacer_short" in counts_dict):
             if n_total == 0:
-                return False, MESSAGE_POLICY["spacer"]["count_fail"]
+                return False, MESSAGE_POLICY["spacer"]["none_detected"]
 
             if n_short == 0 and n_long >= 1:
                 return False, MESSAGE_POLICY["spacer"]["short_missing"]
@@ -693,18 +705,11 @@ def advice_text() -> str:
             if n_short != 1 or n_long != 1 or n_total != 2:
                 return False, MESSAGE_POLICY["spacer"]["count_fail"]
 
-        if "E_SPACER_SHORT_MISSING" in codes:
-            return False, MESSAGE_POLICY["spacer"]["short_missing"]
-
-        if "E_SPACER_LONG_MISSING" in codes:
-            return False, MESSAGE_POLICY["spacer"]["long_missing"]
-
         if "E_SPACER_COUNT_MISMATCH" in codes:
+            if n_total == 0:
+                return False, MESSAGE_POLICY["spacer"]["none_detected"]
             return False, MESSAGE_POLICY["spacer"]["count_fail"]
 
-        if "E_SPACER_TYPE_CONFUSION" in codes:
-            return False, MESSAGE_POLICY["spacer"]["type_confusion"]
-
         if (
             "E_SPACER_ASSIGNMENT_FAIL" in codes
             or "E_SPACER2_MISSING" in codes

evaluation_function/evaluation_test.py

@@ -5,7 +5,7 @@
 import cv2
 import numpy as np
 from lf_toolkit.evaluation import Params
-from .evaluation import evaluation_function
+from .evaluation import _build_student_message, evaluation_function
 from .yolo_pipeline import _quality_advice, compute_image_quality_metrics
 
 
@@ -193,6 +193,47 @@ def test_quality_advice_soft_warnings_cover_all_components(self):
         self.assertIn("little noisy", advice)
         self.assertNotIn("retake", advice)
 
+    def test_spacer_feedback_reports_short_missing_from_counts(self):
+        is_correct, message = _build_student_message(
+            task="spacer",
+            img_bgr=np.zeros((10, 10, 3), dtype=np.uint8),
+            out={"counts": {"spacer_long": 1, "spacer_short": 0}},
+            errors=[],
+            selected_errors=[],
+            part_type="",
+        )
+
+        self.assertFalse(is_correct)
+        self.assertIn("short spacer", message.lower())
+
+    def test_spacer_feedback_reports_long_missing_from_counts(self):
+        is_correct, message = _build_student_message(
+            task="spacer",
+            img_bgr=np.zeros((10, 10, 3), dtype=np.uint8),
+            out={"counts": {"spacer_long": 0, "spacer_short": 1}},
+            errors=[],
+            selected_errors=[],
+            part_type="",
+        )
+
+        self.assertFalse(is_correct)
+        self.assertIn("long spacer", message.lower())
+
+    def test_spacer_feedback_reports_no_spacers_detected(self):
+        errors = [{"code": "E_SPACER_COUNT_MISMATCH", "message": "No spacers detected."}]
+
+        is_correct, message = _build_student_message(
+            task="spacer",
+            img_bgr=np.zeros((10, 10, 3), dtype=np.uint8),
+            out={"counts": {"spacer_long": 0, "spacer_short": 0}, "errors": errors},
+            errors=errors,
+            selected_errors=errors,
+            part_type="",
+        )
+
+        self.assertFalse(is_correct)
+        self.assertIn("no spacers", message.lower())
+
 
 if __name__ == "__main__":
     unittest.main()