Update app.py

app.py

@@ -8,6 +8,7 @@ from streamlit_sortables import sort_items
 
 # Function to generate thumbnail from PDF
 def get_pdf_thumbnail(uploaded_file):
+    uploaded_file.seek(0)  # Reset the file pointer to the beginning
     doc = fitz.open(stream=uploaded_file.read(), filetype="pdf")
     page = doc.load_page(0)
     pix = page.get_pixmap()
@@ -48,17 +49,18 @@ if uploaded_files:
     if st.button("Merge PDFs"):
         merger = PdfMerger()
         for file in reordered_files:
+            file.seek(0)  # Reset the file pointer before merging
             merger.append(file)
-
+    
         output_filename = "combined_document.pdf"
         with open(output_filename, "wb") as output_file:
             merger.write(output_file)
-
+    
         st.success("PDF pages combined successfully!")
-
+    
         # Provide download link
         with open(output_filename, "rb") as f:
             st.download_button("Download Combined PDF", f, file_name=output_filename, mime="application/pdf")
-
+    
         # Clean up
         os.remove(output_filename)