update app.py

app.py

@@ -55,7 +55,6 @@ with open(os.path.expanduser("~/.config/earthengine/credentials"), "w") as f:
     f.write(earthengine_credentials)
 
 ee.Initialize(project='ee-yashsacisro24')
-
 # Imagery base selection
 imagery_base = st.selectbox("Select Imagery Base", ["Sentinel", "Landsat"], index=0)
 
@@ -74,8 +73,26 @@ st.title(f"{imagery_base} Dataset")
 # Select dataset category (main selection)
 main_selection = st.selectbox(f"Select {imagery_base} Dataset Category", list(data.keys()))
 
+# Initialize sub_selection and dataset_id as None
+sub_selection = None
+dataset_id = None
+
+# If a category is selected, display the sub-options (specific datasets)
+if main_selection:
+    sub_options = data[main_selection]["sub_options"]
+    sub_selection = st.selectbox(f"Select Specific {imagery_base} Dataset ID", list(sub_options.keys()))
+
+    # Display the selected dataset ID based on user input
+    if sub_selection:
+        st.write(f"You selected: {main_selection} -> {sub_options[sub_selection]}")
+        st.write(f"Dataset ID: {sub_selection}")
+        dataset_id = sub_selection  # Use the key directly as the dataset ID
+
+# Earth Engine Index Calculator Section
+st.header("Earth Engine Index Calculator")
+
 # Load band information based on selected dataset
-if main_selection and sub_selection:
+if main_selection and sub_selection:  # Now safe because sub_selection is initialized
     dataset_bands = data[main_selection]["bands"].get(sub_selection, [])
     st.write(f"Available Bands for {sub_options[sub_selection]}: {', '.join(dataset_bands)}")
 
@@ -114,7 +131,6 @@ if main_selection and sub_selection:
         # Validate the formula
         def validate_formula(formula, selected_bands):
             allowed_chars = set(" +-*/()0123456789.")
-            # Match alphanumeric terms including underscores (for Landsat bands like SR_B1)
             terms = re.findall(r'[a-zA-Z][a-zA-Z0-9_]*', formula)
             invalid_terms = [term for term in terms if term not in selected_bands]
             if invalid_terms: