Fix PDF upload validation error

- Add null check for pdf_file parameter
- Validate file has 'name' attribute
- Check if file exists before opening
- Check for empty PDFs (0 pages)
- Better error messages with emoji
- Add traceback for debugging

Fixes: 'NoneType' object has no attribute 'name' error

app.py

@@ -113,9 +113,25 @@ def process_pdf(pdf_file, prompt_text):
         str: Extracted text from PDF pages
     """
     try:
+        # Validate file upload
+        if pdf_file is None:
+            return "❌ Please upload a PDF file first."
+
+        if not hasattr(pdf_file, 'name'):
+            return "❌ Invalid file upload. Please try again."
+
+        # Check if file exists
+        if not os.path.exists(pdf_file.name):
+            return f"❌ File not found: {pdf_file.name}"
+
         # Open PDF
         pdf_document = fitz.open(pdf_file.name)
         total_pages = len(pdf_document)
+
+        if total_pages == 0:
+            pdf_document.close()
+            return "❌ PDF file is empty (0 pages)."
+
         results = []
 
         # Process first 3 pages (to avoid timeout)
@@ -151,7 +167,9 @@ def process_pdf(pdf_file, prompt_text):
         return "\n".join(results)
 
     except Exception as e:
-        return f"Error processing PDF: {str(e)}"
+        import traceback
+        error_details = traceback.format_exc()
+        return f"❌ Error processing PDF: {str(e)}\n\nPlease make sure you uploaded a valid PDF file."
 
 # Create Gradio Interface
 with gr.Blocks(title="DeepSeek-OCR Studio", theme=gr.themes.Soft()) as demo: