#!/usr/bin/env python3
"""
Run inside a directory, and it moves every non-trivial file up to the
top-level.

I use this to flatten out heavily-nested directory hierarchies, when I need
to sort through the files by hand and want to see what I've got.

It tries to handle cases where different files exist with the same name, but
it may not be robust.  Use with caution.

By default it only prints what it's going to do, you need to add the flag `--run`
for it to do anything.
"""

import filecmp
import os
import secrets
import shutil
import sys


def mv(src, dst):
    print(f'mv {src} ~> {dst}')
    if '--run' in sys.argv:
        os.rename(src, dst)


def rm(path):
    print(f'rm {path}')
    if '--run' in sys.argv:
        os.unlink(path)


if __name__ == '__main__':
    for root, _, filenames in os.walk('.'):
        if root == '.':
            continue

        for f in filenames:
            f_src = os.path.join(root, f)

            if f == '.DS_Store':
                rm(f_src)
                continue

            f_dst = f

            if os.path.exists(f_dst) and filecmp.cmp(f_src, f_dst):
                rm(f_src)
                continue

            # Add a bit of noise to filenames to avoid duplication
            while os.path.exists(f_dst):
                name, ext = os.path.splitext(f)
                f_dst = name + '__' + secrets.token_hex(3) + ext

            mv(src=f_src, dst=f_dst)

    # Clean up empty directories
    while True:
        is_finished = True
        for root, dirnames, filenames in os.walk('.'):
            if not dirnames and not filenames:
                shutil.rmtree(root)
                is_finished = False

        if is_finished:
            break