fix

app.py

@@ -96,30 +96,47 @@ if selected_model == 'Cas9':
         ('on-target', 'off-target'),
         key='target_selection'
     )
+    if 'current_gene_symbol' not in st.session_state:
+        st.session_state['current_gene_symbol'] = ""
 
-    if target_selection == 'on-target':
-        # Gene symbol entry
-        gene_symbol = st.text_input('Enter a Gene Symbol:', placeholder="e.g., FOXA1", key='gene_symbol')
-
-        if 'current_gene_symbol' not in st.session_state:
-            st.session_state['current_gene_symbol'] = ""
-        # Function to clean up old files
-        def clean_up_old_files(gene_symbol):
-            genbank_file_path = f"{gene_symbol}_crispr_targets.gb"
-            bed_file_path = f"{gene_symbol}_crispr_targets.bed"
-            csv_file_path = f"{gene_symbol}_crispr_predictions.csv"
-            for path in [genbank_file_path, bed_file_path, csv_file_path]:
-                if os.path.exists(path):
-                    os.remove(path)
-
-        if st.session_state['current_gene_symbol'] and gene_symbol != st.session_state['current_gene_symbol']:
+    # Define a function to clean up old files
+    def clean_up_old_files(gene_symbol):
+        genbank_file_path = f"{gene_symbol}_crispr_targets.gb"
+        bed_file_path = f"{gene_symbol}_crispr_targets.bed"
+        csv_file_path = f"{gene_symbol}_crispr_predictions.csv"
+        for path in [genbank_file_path, bed_file_path, csv_file_path]:
+            if os.path.exists(path):
+                os.remove(path)
+
+    # Gene symbol entry
+    gene_symbol = st.text_input('Enter a Gene Symbol:', placeholder="e.g., FOXA1", key='gene_symbol')
+
+    # Handle gene symbol change and file cleanup
+    if gene_symbol != st.session_state['current_gene_symbol'] and gene_symbol:
+        if st.session_state['current_gene_symbol']:
+            # Clean up files only if a different gene symbol is entered and a previous symbol exists
             clean_up_old_files(st.session_state['current_gene_symbol'])
+        # Update the session state with the new gene symbol
+        st.session_state['current_gene_symbol'] = gene_symbol
 
+    if target_selection == 'on-target':
         # Prediction button
         predict_button = st.button('Predict on-target')
 
         # Process predictions
         if predict_button and gene_symbol:
+            with st.spinner('Predicting... Please wait'):
+                predictions, gene_sequence = cas9on.process_gene(gene_symbol, cas9on_path)
+                sorted_predictions = sorted(predictions, key=lambda x: x[-1], reverse=True)[:10]
+                st.session_state['on_target_results'] = sorted_predictions
+                st.session_state['gene_sequence'] = gene_sequence  # Save gene sequence in session state
+
+            # Notify the user once the process is completed successfully.
+            st.success('Prediction completed!')
+            st.session_state['prediction_made'] = True
+
+            # Process predictions
+        if 'prediction_made' in st.session_state and st.session_state['prediction_made']:
             with st.spinner('Predicting... Please wait'):
                 predictions, gene_sequence = cas9on.process_gene(gene_symbol, cas9on_path)
                 sorted_predictions = sorted(predictions, key=lambda x: x[-1], reverse=True)[:10]
@@ -192,7 +209,10 @@ if selected_model == 'Cas9':
                 # Display the plot
                 st.plotly_chart(fig)
 
-                if gene_sequence:
+                if 'gene_sequence' in st.session_state and st.session_state['gene_sequence']:
+                    gene_symbol = st.session_state['current_gene_symbol']
+                    gene_sequence = st.session_state['gene_sequence']
+
                     # Define file paths
                     genbank_file_path = f"{gene_symbol}_crispr_targets.gb"
                     bed_file_path = f"{gene_symbol}_crispr_targets.bed"
@@ -221,8 +241,7 @@ if selected_model == 'Cas9':
                     # Links for user guidance on using the downloaded files
                     st.markdown(
                         "GenBank files can be visualized using [PyGenomeViz](https://pygenomeviz.streamlit.app/). "
-                        "BED files can be used with the [UCSC Genome Browser](https://genome.ucsc.edu/cgi-bin/hgCustom)."
-                    )
+                        "BED files can be used with the [UCSC Genome Browser](https://genome.ucsc.edu/cgi-bin/hgCustom).")
 
                     # # Visualize the GenBank file using pyGenomeViz
                     # gv = GenomeViz(