Untitled

import os
from PyPDF2 import PdfReader, PdfWriter

desktop = os.path.join(os.path.expanduser("~"), "Desktop")
input_folder = os.path.join(desktop, "input")
master_folder = os.path.join(desktop, "master")
output_folder = os.path.join(desktop, "output")

os.makedirs(output_folder, exist_ok=True)


master_files = [f for f in os.listdir(master_folder) if f.lower().endswith(".pdf")]
if not master_files:
    raise FileNotFoundError("No master PDF found in master folder.")
master_path = os.path.join(master_folder, master_files[0])
master_reader = PdfReader(master_path)

for input_file in os.listdir(input_folder):
    if not input_file.lower().endswith(".pdf"):
        continue

    input_path = os.path.join(input_folder, input_file)
    input_reader = PdfReader(input_path)
    writer = PdfWriter()

    page_count = min(len(input_reader.pages), len(master_reader.pages))

    for i in range(page_count):
        writer.add_page(input_reader.pages[i])
        writer.add_page(master_reader.pages[i])


    output_path = os.path.join(output_folder, f"merged_{input_file}")
    with open(output_path, "wb") as f_out:
        writer.write(f_out)

print("Merging complete. Files saved in output folder.")