Update app.py

app.py

@@ -1296,101 +1296,60 @@ def locator_page():
     except Exception:
         pass
 
-    # ----------------------------
-    # Show map with drawing tools
-    # ----------------------------
-    
-        # ----------------------------
-    # Show map with drawing tools
-    # ----------------------------
+    # --------------------------------------------------------------------------
+    # Section: Display Map, Handle Drawings, and Trigger Computation
+    # --------------------------------------------------------------------------
+
     st.markdown("👉 Draw a polygon/rectangle on the map (use draw tool). After drawing, click **Compute Summaries**.")
-    
-    # VITAL: Capture the map's state, which includes drawings, from the frontend.
+
+    # VITAL: Render the map and capture its state from the frontend on every script run.
     map_data = m.to_streamlit(height=700, responsive=True)
 
-    # Check if a new polygon was drawn and save it to session_state immediately.
-    # geemap returns the last drawn feature in 'last_object'.
+    # Immediately save any newly drawn geometry to the session_state to persist it.
+    # geemap returns the last drawn feature in the 'last_object' key.
     if map_data and map_data.get("last_object"):
         st.session_state["roi_geojson"] = json.dumps(map_data["last_object"])
 
-    # Button to compute summaries
-    if st.button("Compute Summaries"):
-        # The button click causes a rerun, but the ROI is now safely in session_state.
-        st.session_state["compute_button"] = True
-    
-    # Update the helper function to prioritize session_state
-    def get_roi_from_map(m):
-        # Prefer session_state (persists across reruns)
+    # Define a robust helper function to retrieve the ROI.
+    def get_roi_from_map():
         if "roi_geojson" in st.session_state and st.session_state["roi_geojson"]:
             try:
-                # The geojson from the map is a full feature, extract the 'geometry' part
+            # The data from the map is a full GeoJSON "Feature".
+            # We need to extract only the 'geometry' part for Earth Engine.
                 feature = json.loads(st.session_state["roi_geojson"])
-                return ee.Geometry(feature['geometry'])
+            return ee.Geometry(feature['geometry'])
             except (json.JSONDecodeError, KeyError, Exception) as e:
-                st.warning(f"Could not parse stored ROI: {e}")
-                return None
-        # Fallback for other potential geemap attributes (less reliable on reruns)
-        if hasattr(m, "user_roi") and m.user_roi:
-            try:
-                 return m.user_roi
-            except Exception:
-                 return None
-        return None
+                st.warning(f"Could not parse the stored ROI. Please try drawing it again. Error: {e}")
+            # Clear the invalid ROI to prevent repeated errors
+                del st.session_state["roi_geojson"]
+            return None
+    return None # Return None if no ROI has been saved yet.
 
-    # If user pressed compute, extract ROI and compute
-    if st.session_state.get("compute_button", False):
-        roi = get_roi_from_map(m)
-        if roi is None:
-             st.error("No drawn ROI found. Please draw a polygon/rectangle and press Compute Summaries again.")
-             # Reset button state to allow for another attempt
-             st.session_state["compute_button"] = False
-             return # Use return instead of st.stop() in this context
-
-        # ... the rest of your computation code follows here ...
-        # (Make sure to reset the button state at the end of the computation block)
-        # st.session_state["compute_button"] = False
-
-    # Button to compute summaries (we'll fetch ROI from map object)
+    # Initialize the button's state if it doesn't exist
     if "compute_button" not in st.session_state:
-        st.session_state["compute_button"] = False
+         st.session_state["compute_button"] = False
+    
+    # When the button is clicked, set its state to True for the subsequent rerun
     if st.button("Compute Summaries"):
         st.session_state["compute_button"] = True
-    
-    # get ROI helper (try multiple attributes)
-    '''def get_roi_from_map(m):
-    # Prefer session_state (persists across reruns)
-        if "roi_geojson" in st.session_state:
-            try:
-                return ee.Geometry(json.loads(st.session_state["roi_geojson"]))
-            except Exception:
-                pass'''
-
-    # fallback checks
-        if hasattr(m, "user_roi") and m.user_roi:
-            try:
-                 return ee.Geometry(m.user_roi.toGeoJSONString())
-            except Exception:
-                 return None
 
-        return None
-
-    # If user pressed compute, extract ROI and compute
+    # This block runs ONLY if the compute button was clicked in the previous run.
     if st.session_state.get("compute_button", False):
-        roi = get_roi_from_map(m)
-        if roi is None:
-             st.error("No drawn ROI found. Please draw a polygon/rectangle and press Compute Summaries again.")
-        return
-
-        # ensure ROI is ee.Geometry
-        try:
-            if not isinstance(roi, ee.Geometry):
-                roi = ee.Geometry(roi)
-        except Exception:
-            st.error("Failed to parse ROI as Earth Engine geometry.")
-            return
+    # Immediately reset the button's state to False.
+    # This prevents the computation from running again on the next interaction.
+        st.session_state["compute_button"] = False
+    
+    # Retrieve the ROI using our reliable helper function
+         roi = get_roi_from_map()
 
+    if roi is None:
+        st.error("No drawn ROI found. Please draw a polygon or rectangle and press 'Compute Summaries' again.")
+    else:
+        # --- YOUR COMPUTATION LOGIC GOES HERE ---
+        # This is where you place the code that was below the original ROI check.
         st.success("Polygon found — computing (this may take a few seconds)...")
 
+        
         # choose soil depth via UI (0-200cm). If soil_img is OpenLandMap provide depth selection; if SoilGrids, show its bands
         chosen_soil_band = None
         if soil_img is not None: