fix: normalize datetime objects to naive format in router and refactor forecast message construction

src/aeros_simulation/router.py

@@ -510,7 +510,7 @@ async def get_forecast_eaf(
     from .schema import SimulationInput
 
     # 1. Get current time
-    now = datetime.now()
+    now = datetime.now().replace(tzinfo=None)
 
     # 2. Determine Last Overhaul Date from Master Data
     oh_record = await _get_or_create_master_data(db_session, "Last Overhaul Date", 0)
@@ -522,15 +522,16 @@ async def get_forecast_eaf(
         oh_date_str = oh_record.value_string
 
     try:
-        oh_date = datetime.fromisoformat(oh_date_str)
+        # Ensure oh_date is naive
+        oh_date = datetime.fromisoformat(oh_date_str).replace(tzinfo=None)
     except Exception:
-        oh_date = datetime(now.year, 1, 1)
+        oh_date = datetime(now.year, 1, 1).replace(tzinfo=None)
 
     # 3. Calculate Age in Hours (Offset)
     # Using the helper from utils.py
     offset_hours = hours_between(oh_date, now)
 
-    #start date is oh + offset
+    # start date is oh + offset
     start_date = oh_date + timedelta(hours=offset_hours)
 
     # 4. Define Forecast Window
@@ -573,6 +574,12 @@ async def get_forecast_eaf(
         total_ut = plant_result.get("totalUpTime", 0)
         efor = (total_dt / (total_dt + total_ut)) * 100 if (total_dt + total_ut) > 0 else 0
 
+        forecast_msg = (
+            f"Forecast generated successfully, "
+            f"start date: {start_date.strftime('%Y-%m-%d %H:%M:%S')}, "
+            f"end_date: {(start_date + timedelta(hours=duration)).strftime('%Y-%m-%d %H:%M:%S')}"
+        )
+
         return StandardResponse(
             data={
                 "range": time_range,
@@ -582,7 +589,7 @@ async def get_forecast_eaf(
                 "sim_duration_hours": duration,
                 "reference_oh_date": oh_date_str
             },
-            message=f"Forecast generated successfully, start date: {start_date.strftime('%Y-%m-%d %H:%M:%S')}, end_date: {(start_date + timedelta(hours=duration)).strftime('%Y-%m-%d %H:%M:%S')}"
+            message=forecast_msg
         )
     except Exception as e:
         import logging