"""
Extracts all .gz files from a given directory and writes the uncompressed
outputs to an 'out/' subfolder within that directory.

Useful for simple, batch decompression of Gzip files via CLI.
"""

import gzip
from pathlib import Path


def unzip_gzip(file: Path, target: str):
    with gzip.open(file, 'rb') as r:
        with open(target, 'wb') as w:
            return w.write(r.read())


def unzip_gzfiles(dirpath: Path) -> None:
    """Unzips all .gz files from a given directory into an 'out/' folder."""
    gzfiles = list(dirpath.glob('*.gz'))

    if not gzfiles:
        print(f'ℹ️ No .gz files found in "{dirpath}"')
        return None

    # Create a directory to output the files
    Path(f'{dirpath}/out').mkdir(exist_ok=True)

    for file in gzfiles:
        filename = file.name.removesuffix('.gz')

        if not file.is_file():
            continue

        if unzip_gzip(file, f'{dirpath}/out/{filename}'):
            print(f'✅ Unzipped: {file.name}')


if __name__ == '__main__':
    try:
        dirpath = Path(input('📂 Enter the directory containing .gz files: '))

        if not dirpath.exists() or not dirpath.is_dir():
            print(f'❌ Directory "{dirpath}" not found or is not a folder.')
            exit(1)

        unzip_gzfiles(dirpath)
    except KeyboardInterrupt:
        print('\n👋 Cancelled by user')
    except Exception as e:
        print(f'💥 Error: {e}')