cp_bt_transmission

#!/usr/bin/python3
import os
import subprocess
from pathlib import PosixPath

home = os.getenv('HOME')

seed_folder = PosixPath(home + '/Downloads/a_torrents/seeding')
torr_folder = PosixPath(home + '/.config/transmission/torrents')
finished_folder = PosixPath(home + '/Downloads/a_torrents/a_finished')
suffix_witness = '.copied_torrent'


def is_witness(p):
    return p.suffix == suffix_witness


def witness_exists(p):
    return PosixPath(str(p) + suffix_witness).exists()


def create_witness(p):
    subprocess.call(['touch', str(p) + suffix_witness])


def clean_witness():
    print("Cleaning witness files")
    for f in seed_folder.glob('*' + suffix_witness):
        assert is_witness(f)
        torr = f.parent / PosixPath('.'.join(f.name.split('.')[:-1]))
        if not torr.exists():
            subprocess.call(['gvfs-trash', str(f)])
    print("Done")


def remove_unless_seeded():
    print("Removing files that are not seeded anymore")
    seeded_torrents = set(
        (t.name for t in seed_folder.glob('*') if not is_witness(t)))

    torrent_files = set((
        '.'.join(tf.name.split('.')[:-2])
        for tf in torr_folder.glob('*.torrent')
    ))

    to_del = seeded_torrents.difference(torrent_files)

    for file_to_del in to_del:
        fn = seed_folder / PosixPath(file_to_del)
        print("Removing {}".format(fn))
        subprocess.call(['gvfs-trash', str(seed_folder / fn)])
    print("Done")


def cp_seeded():
    print("Copying files that have not been copied yet")
    for f in seed_folder.glob('*'):
        if not witness_exists(f) and not is_witness(f):
            print("Copying {}".format(f.name))
            subprocess.call(['cp', '-r', str(f), str(finished_folder)])
            create_witness(f)
    print("Done")


if __name__ == '__main__':
    seed_folder.mkdir(parents=True, exist_ok=True)
    torr_folder.mkdir(parents=True, exist_ok=True)
    finished_folder.mkdir(parents=True, exist_ok=True)

    assert seed_folder.exists()
    assert torr_folder.exists()
    assert finished_folder.exists()

    cp_seeded()
    remove_unless_seeded()
    clean_witness()