---

@'
from pathlib import Path
from pypdf import PdfReader, PdfWriter
import os

folder = Path(os.environ["USERPROFILE"]) / "Desktop" / "LR4"

source = folder / "LR4_PDF_encrypted.pdf"
target = folder / "LR4_FINAL_PROTECTED.pdf"

password = "P7d!"

if not source.exists():
    raise FileNotFoundError(source)

reader = PdfReader(str(source))

if reader.is_encrypted:
    raise RuntimeError("Source already encrypted")

writer = PdfWriter(clone_from=str(source))

writer.encrypt(
    user_password=password,
    owner_password="OwnerPassword2026",
    algorithm="AES-128"
)

writer.write(str(target))

# Independent verification
test = PdfReader(str(target))
is_encrypted = test.is_encrypted

empty_result = test.decrypt("")
correct_result = PdfReader(str(target)).decrypt(password)

print()
print("=== PDF VERIFICATION ===")
print("File:", target)
print("Encrypted:", is_encrypted)
print("Empty password accepted:", empty_result != 0)
print("Correct password accepted:", correct_result != 0)

if is_encrypted and empty_result == 0 and correct_result != 0:
    print("SUCCESS: PDF IS PROTECTED!")
else:
    raise RuntimeError("Protection verification FAILED")
'@ | py -