rename.py

# rename.py
# usage: python3 rename.py ~/pics
import sys
from pathlib import Path


def print_usage():
    print('usage: python3 rename.py [target-dir]', file=sys.stderr)


def main():
    if len(sys.argv) != 2:
        print_usage()
        exit(-1)
    dir_ = Path(sys.argv[1])
    if not dir_.exists():
        print(f'{sys.argv[1]} not exist', file=sys.stderr)
        exit(-1)

    files_to_rename = []
    for file in dir_.rglob('*.JPG'):
        print('plan to rename file:', file)
        files_to_rename.append(file)

    ret = input('press \'y\' to continue:')
    if ret.strip() not in ['y', 'Y']:
        exit(0)

    for file in files_to_rename:
        new_file = file.parent / (file.name.replace('.JPG', '.jpg'))
        file.rename(new_file)


if __name__ == '__main__':
    main()