Update app.py

app.py

@@ -39,6 +39,8 @@ def clean_data(df):
 
 def upload_file(file):
     global df_global
+    if file is None:
+        return pd.DataFrame({"Error": ["No file uploaded."]})
     ext = os.path.splitext(file.name)[-1]
     df = pd.read_csv(file.name) if ext == ".csv" else pd.read_excel(file.name)
     df = clean_data(df)
@@ -153,8 +155,8 @@ with gr.Blocks() as demo:
     with gr.Row():
         with gr.Column():
             file_input = gr.File(label="Upload CSV or Excel", type="filepath")
-            upload_btn = gr.Button("Upload & Clean")
             df_output = gr.DataFrame(label="Cleaned Data Preview")
+            file_input.change(fn=upload_file, inputs=file_input, outputs=df_output)
 
         with gr.Column():
             insights_output = gr.Textbox(label="Insights from SmolAgent", lines=15)
@@ -170,7 +172,6 @@ with gr.Blocks() as demo:
         shap_img = gr.Image(label="SHAP Summary Plot")
         lime_img = gr.Image(label="LIME Explanation")
 
-    upload_btn.click(fn=upload_file, inputs=file_input, outputs=df_output)
     agent_btn.click(fn=run_agent, inputs=df_output, outputs=insights_output)
     train_btn.click(fn=train_model, inputs=df_output, outputs=[metrics_output, trials_output])
     explain_btn.click(fn=explainability, inputs=df_output, outputs=[shap_img, lime_img])