Find orphan files based on the extension and move them into directory, typically used for removing raw picture where jpeg have been removed

pic_remove_orphans.py

#!/usr/bin/env python

import os, os.path
import argparse

parser = argparse.ArgumentParser(description='Find orphan files based on the extension and move them into directory')
parser.add_argument('--dir', nargs='?', default=os.getcwd(), help='Directory to process (default CWD)')
parser.add_argument('--dest', nargs='?', default='orphans', help='Destination directory (default orphans)')
parser.add_argument('--delete', action='store_true', default=False, help='Delete files instead of backing them up')
parser.add_argument('--sensitive', action='store_true', default=False, help='Case sensitive for extensions')
parser.add_argument('--dry-run', action='store_true', default=False, help='Make a simulation (do not effectivily move files)')
parser.add_argument('--no-checks', action='store_true', default=False, help='Disable validation if the there is too many orphans')
parser.add_argument('base_extension', help='Base extension')

def find_extension(f):
	base, extension = os.path.splitext(f)
	if extension and len(extension) > 1:
		return extension[1:]
	return ''

def accept_base(args):
	if not args.sensitive:
		return lambda f: find_extension(f).upper() == args.base_extension.upper()

	return lambda f: find_extension(f) == args.base_extension

def is_file_with_ext(f):
	base, extension = os.path.splitext(f)
	return base != '' and extension != ''

def orphans(bases):
	base_names = map(lambda f: os.path.splitext(f)[0], bases)
	return lambda f: os.path.splitext(f)[0] not in base_names

def process_orphan(f, args):
	path = os.path.join(args.dir, f)
	if args.delete:
		print 'Deleting ' + f + ' ...'
		#if not args.dry_run:
		#	os.remove(path)
	else:
		dest = os.path.join(args.dir, args.dest)
		if not os.path.exists(dest): os.makedirs(dest)
		print 'Moving ' + f + ' to ' + dest + ' ...'
		if not args.dry_run:
			os.rename(os.path.join(args.dir, f), os.path.join(dest, f))

def ratio(files, bases):
	f = float(len(files))
	b = float(len(bases))
	return (f - b) / f

if __name__ == '__main__':
	args = parser.parse_args()
	files = [f for f in os.listdir(args.dir)
		if os.path.isfile(os.path.join(args.dir, f)) and is_file_with_ext(f)]
	bases = filter(accept_base(args), files)
	ratio = ratio(files, bases)
	if not args.no_checks and ratio > 0.7:
		if raw_input('> There are many orphans, do you want to continue ? [y/n]: ') != 'y':
			import sys
			sys.exit(1)
	others = filter(orphans(bases), files)
	for f in others: process_orphan(f, args)