#!/usr/local/bin/python

import pathlib
import subprocess

from copy_snapshots_to_remote import get_member_name

SSH_KEY_FILE = "/mnt/Datenspeicher/snap-backup-dataset/backup_key"
SSH_REMOTE = "zfs_snap_backup@etha.cpi.imtek.uni-freiburg.de"

REMOTE_PATH = "zfs-backups"

ZFS_POOL = "Datenspeicher"
ZFS_ELAB_PREFIX = "elabfs-"

TMP_BACKUP_FOLDER = "/mnt/Datenspeicher/snap-backup-dataset/temporary-backups"


def remote_call(arguments):
    """ makes runs an command on the remote backup server

    :params arguments: list of command line arguments and parameters
    :returns: string of the command output
    :raises subprocess.CalledProcessError: if command has not an exit value of 0
    """
    cmd = ["ssh", "-i", SSH_KEY_FILE, SSH_REMOTE]
    cmd.extend(arguments)
    result = subprocess.run(" ".join(cmd), check=True,
        stdout=subprocess.PIPE,
        universal_newlines=True, shell=True)
    return result.stdout


def get_local_backup_members():
    tmp_folder = pathlib.Path(TMP_BACKUP_FOLDER)
    backups = (i for i in tmp_folder.iterdir() if i.suffix==".gz")
    return {get_member_name(b.name) for b in backups}


def get_remote_checksums():
    result = {}
    for member in get_local_backup_members():
        remote_path =  f"{REMOTE_PATH}/{member}/\*"
        cmd_result = remote_call(["sha256sum", remote_path])
        print(cmd_result)


if __name__ == "__main__":
    get_remote_checksums()