utils.py

"""
utils.py
--------
Provides utility functions for compressing and encrypting backup files.

This module uses Python's built-in `zipfile` module to create ZIP files
with basic password protection (ZipCrypto).

Author: Group 28
Date: 24 July 2025
"""

import zipfile
import os

def encrypt_and_compress(source_path, output_path, password):
    """
    Compresses a file or folder into a ZIP archive with basic encryption.

    Parameters:
    source_path (str): Path to the file or folder to compress.
    output_path (str): Path to save the ZIP file.
    password (str): Password to protect the ZIP file (ZipCrypto).

    Returns:
    str: Path to the encrypted ZIP file.
    """

    try:
        with zipfile.ZipFile(output_path, 'w', compression=zipfile.ZIP_DEFLATED) as zipf:
            # Convert password to bytes (zipfile uses ZipCrypto)
            zipf.setpassword(password.encode())

            if os.path.isfile(source_path):
                # Handle single file
                arcname = os.path.basename(source_path)
                zipf.write(source_path, arcname=arcname)
            else:
                # Handle directory
                for foldername, subfolders, filenames in os.walk(source_path):
                    for filename in filenames:
                        full_path = os.path.join(foldername, filename)
                        arcname = os.path.relpath(full_path, start=source_path)
                        zipf.write(full_path, arcname=arcname)

        print(f"✅ Encrypted backup created: {output_path}")
        return output_path

    except Exception as e:
        print(f"❌ Encryption error: {e}")
        return None