Update app.py

app.py

@@ -23,9 +23,18 @@ def extract_text_from_pdf(pdf_path: str) -> str:
     return text
 
 def classify_topic(text: str, topics: List[str]) -> str:
-    classifier = pipeline("zero-shot-classification", model="valhalla/distilbart-mnli-12-3")
+    if not text.strip():
+        return "Unknown (no text extracted)"
+    if not topics:
+        return "Unknown (no topics provided)"
+
+    classifier = pipeline("zero-shot-classification", model="facebook/bart-large-mnli")
     result = classifier(text[:1000], candidate_labels=topics)
-    return result['labels'][0]
+
+    if 'labels' in result and len(result['labels']) > 0:
+        return result['labels'][0]
+    return "Unknown (classification failed)"
+
 
 def generate_audio(text: str, output_path: str):
     tts = gTTS(text)
@@ -58,8 +67,12 @@ if submitted and uploaded_file and topic_input:
     
             text = extract_text_from_pdf(file_path)
             topic_list = [t.strip() for t in topic_input.split(",") if t.strip()]
-            classified_topic = classify_topic(text, topic_list)
-            summary = summarize_text(text)
+            if not text.strip():
+                st.error("❌ No text could be extracted from the PDF. Try another file.")
+            else:
+                classified_topic = classify_topic(text, topic_list)
+                summary = summarize_text(text)
+
     
             st.markdown(f"### 🧠 Classified Topic: `{classified_topic}`")
             st.markdown("### ✍️ Summary:")