from argparse import ArgumentParser
from pathlib import Path

import toml

from openwrt_backup.retrieve import make_backup_on_remote, retrieve_backup_on_remote
from openwrt_backup.utils import (
    client_from_config,
    exec_remote,
    get_new_backup_filepath,
)
from openwrt_backup.config import CONFIG_DATA  # noqa
from openwrt_backup.prune import get_all_but_last_n


def do_prune(dest_path: Path, n: int, dry, hostname=None):
    if dry:
        to_delete = get_all_but_last_n(dest_path, n - 1, hostname)
    else:
        to_delete = get_all_but_last_n(dest_path, n, hostname)
    for f in to_delete:
        if dry:
            print(f"Deleting: {f}")
        else:
            f.unlink()


def do_backup(
    config_hostname,
    ssh_config_root: Path,
    backup_path: Path,
    tmp_path: Path,
    time_format,
    dry,
):
    client = client_from_config(config_hostname, ssh_config_root)
    stdout, stderr = exec_remote(client, "echo $HOSTNAME")
    hostname = stdout.read().decode().rstrip()
    dest = get_new_backup_filepath(backup_path, time_format, hostname)
    if dry:
        print(f"Making backup {tmp_path / 'backup_latest.openwrt_backup.tar.gz'}")
        print(
            f"Copying remote {tmp_path / 'backup_latest.openwrt_backup.tar.gz'} to {dest}"
        )
    else:
        backup_on_remote = make_backup_on_remote(client, tmp_path)
        retrieve_backup_on_remote(client, backup_on_remote, dest)
    return hostname


def main():
    global CONFIG_DATA

    parser = ArgumentParser()

    parser.add_argument(
        "-d",
        "--dry",
        action="store_true",
        help="Don't do anything but show what would happen",
    )
    parser.add_argument(
        "-c", "--config", help="config path for backup script", default=None
    )

    subparsers = parser.add_subparsers(dest="action", required=True)
    p_run = subparsers.add_parser(
        "run",
        help=f"Make backup then prune all but the {CONFIG_DATA['backup']['keep']} most recent",
    )
    p_backup = subparsers.add_parser(
        "backup", help="Same as run but do not delete any backups"
    )
    p_dump_config = subparsers.add_parser(  # noqa
        "dump-config", help="Show config and exit"
    )  # noqa
    p_run.add_argument(
        "name", help="Hostname in ssh_config file for openwrt device we need to backup"
    )
    p_backup.add_argument(
        "name", help="Hostname in ssh_config file for openwrt device we need to backup"
    )
    args = parser.parse_args()

    if args.config:
        with open(args.config) as f:
            CONFIG_DATA = toml.load(f)

    if args.action == "dump-config":
        print(toml.dumps(CONFIG_DATA))
        exit(0)

    hostname = do_backup(
        args.name,
        Path(CONFIG_DATA["ssh"]["root"]).expanduser(),
        Path(CONFIG_DATA["backup"]["path"]).expanduser(),
        Path(CONFIG_DATA["router"]["temp"]),
        CONFIG_DATA["backup"]["time_format"],
        args.dry,
    )
    if args.action != "backup":
        do_prune(
            Path(CONFIG_DATA["backup"]["path"]).expanduser(),
            CONFIG_DATA["backup"]["keep"],
            args.dry,
            hostname,
        )