SIENTIAPDE-1579: Switched from replace logic to validation + mapping

model_manager/sientia/models.py

@@ -17,14 +17,35 @@ NORMALIZATION = 'Normalization'
 FEATURE_CREATION = 'Feature Creation'
 LAG_CREATION = 'Lag Creation'
 
+# Allowed frontend date formats and their strftime equivalents (single source of truth)
+FRONTEND_DATE_FORMAT_TO_STRFTIME = {
+    'dd/MM/yyyy HH:mm:ss': '%d/%m/%Y %H:%M:%S',
+    'MM/dd/yyyy HH:mm:ss': '%m/%d/%Y %H:%M:%S',
+    'yyyy/MM/dd HH:mm:ss': '%Y/%m/%d %H:%M:%S',
+    'dd-MM-yyyy HH:mm:ss': '%d-%m-%Y %H:%M:%S',
+    'MM-dd-yyyy HH:mm:ss': '%m-%d-%Y %H:%M:%S',
+    'yyyy-MM-dd HH:mm:ss': '%Y-%m-%d %H:%M:%S',
+}
+ALLOWED_FRONTEND_DATE_FORMATS = frozenset(FRONTEND_DATE_FORMAT_TO_STRFTIME.keys())
+
+
+def validate_frontend_date_format(fmt: str | None) -> None:
+    """Raise ValueError if fmt is set and not one of the allowed frontend date formats."""
+    if not fmt or not fmt.strip():
+        return
+    if fmt not in ALLOWED_FRONTEND_DATE_FORMATS:
+        allowed = ', '.join(sorted(ALLOWED_FRONTEND_DATE_FORMATS))
+        raise ValueError(
+            f'Invalid date_format "{fmt}". Allowed formats: {allowed}'
+        )
+
 
 def _frontend_date_format_to_strftime(fmt: str | None) -> str | None:
-    """Convert front-end date format (e.g. dd/MM/yyyy HH:mm:ss) to Python strftime."""
+    """Convert front-end date format to Python strftime. Validates format; returns None for empty."""
     if not fmt:
         return None
-    out = fmt.replace('yyyy', '%Y').replace('MM', '%m').replace('dd', '%d')
-    out = out.replace('HH', '%H').replace('mm', '%M').replace('ss', '%S')
-    return out
+    validate_frontend_date_format(fmt)
+    return FRONTEND_DATE_FORMAT_TO_STRFTIME[fmt]
 
 
 class LinearRegressionModel(BaseEstimator, TransformerMixin):