Update app.py

app.py

@@ -1331,37 +1331,46 @@ def locator_page():
 
     # Render the map inside Streamlit
     m.to_streamlit(height=600, responsive=True)
-    
+
     # ----------------------------
     # ROI capture helper
     # ----------------------------
     def get_roi_from_map():
-        """Return ee.Geometry or None if no ROI drawn"""
+        """Return ee.Geometry if ROI exists, otherwise None"""
+        roi = None
+
+        # Case 1: User just drew something on the map
         if m.draw_features:
             try:
-                last_feature = m.draw_features[-1]  # last drawn geometry
+                last_feature = m.draw_features[-1]
                 if isinstance(last_feature, dict):
                     geom = last_feature.get("geometry") or last_feature
+                    roi = ee.Geometry(geom)
+                    # Save permanently in session state
                     st.session_state["roi_geojson"] = json.dumps(last_feature)
-                    return ee.Geometry(geom)
             except Exception as e:
-                st.warning(f"Could not parse drawn ROI: {e}")
-                return None
+                st.warning(f"⚠️ Could not parse drawn ROI: {e}")
+                roi = None
+
+        # Case 2: Nothing drawn this run, but we saved ROI earlier
         elif "roi_geojson" in st.session_state:
-            # Restore ROI if already saved in session
             try:
-                geom = json.loads(st.session_state["roi_geojson"]).get("geometry")
-                return ee.Geometry(geom)
-            except Exception:
-                return None
-        return None
-    
-    # Call helper immediately to update ROI
+                saved = json.loads(st.session_state["roi_geojson"])
+                geom = saved.get("geometry") if isinstance(saved, dict) else saved
+                roi = ee.Geometry(geom)
+            except Exception as e:
+                st.warning(f"⚠️ Failed to restore ROI: {e}")
+                roi = None
+
+        return roi
+
+    # Update ROI immediately (persistent between runs)
     roi = get_roi_from_map()
     if roi:
-        st.success("ROI captured successfully ✅")
-
-    
+        st.success("✅ ROI is available and ready for computations")
+    else:
+        st.info("✍️ Please draw a polygon/rectangle/circle before pressing **Compute Summaries**")
+ 
 
     # --- Compute Summaries ---
     if st.button("Compute Summaries"):