#!/usr/bin/env python3

"""update_tracker.py

Description:
This script collects infohashes of all torrents in each qBittorrent instance,
updates opentracker, and reannounces all torrents to their trackers.

Expectations:
- A JSON qBittorrent authentication file at ~/.config/qbittorrent_auth.json
- SSH pubkey access to torrent tracker server root@bttracker.nirn.quest
- rsync installed on the host system running this script

Usage:
    update_tracker.py
    update_tracker.py -h

Options:
    -h, --help      show this help message and exit
"""

import json
import subprocess
import tempfile
from pathlib import Path

from docopt import docopt
from qbittorrent import Client

if __name__ == "__main__":
    args = docopt(__doc__)  # type: ignore

    # JSON file containing authentication info for each qBittorrent instance
    QBITTORRENT_AUTH_FILE = Path.home().joinpath(".config/qbittorrent_auth.json")

    # Open authentication file and load JSON data
    with open(QBITTORRENT_AUTH_FILE, "r") as qbt_auth:
        auth_data = json.load(qbt_auth)

    # Collect infohashes of all torrents in each qBittorrent instance
    torrent_infohashes = []
    for item in auth_data["instances"]:
        qb = Client(item["hostname"])
        qb.login(username=item["username"], password=item["password"])

        for torrent in qb.torrents():
            torrent_infohashes.append(torrent.get("hash"))  # type: ignore

    # Format the infohashes to have a \n at the end
    format_infohashes = [f"{infohash}\n" for infohash in torrent_infohashes]

    # Create a NamedTemporaryFile and write all infohashes to it, one per line
    with tempfile.NamedTemporaryFile() as ntf:
        with open(ntf.name, "w") as tf:
            tf.writelines(format_infohashes)

        # Use scp to copy the infohashes file to the torrent tracker's config
        # directory on the remote torrent tracker server, overwriting the
        # whitelist.txt file
        subprocess.run(
            [
                "scp",
                ntf.name,
                "root@bttracker.nirn.quest:/etc/opentracker/whitelist.txt",
            ]
        )

    # Use SSH to run `systemctl restart opentracker.service` on the remote
    # torrent tracker server
    subprocess.run(
        [
            "ssh",
            "root@bttracker.nirn.quest",
            "systemctl",
            "restart",
            "opentracker.service",
        ]
    )

    # Ensure bttracker.nirn.quest:6969/announce is added to each torrent's
    # tracker list.
    for item in auth_data["instances"]:
        qb = Client(item["hostname"])
        qb.login(username=item["username"], password=item["password"])
        for torrent in qb.torrents():
            qb.add_trackers(
                torrent.get("hash"),  # type: ignore
                "http://bttracker.nirn.quest:6969/announce\nudp://bttracker.nirn.quest:6969/announce",
            )
            print(f"Updated {torrent.get('name')}")  # type: ignore

    # Reannounce all torrents in each qBittorrent instance to their trackers
    for item in auth_data["instances"]:
        qb = Client(item["hostname"])
        qb.login(username=item["username"], password=item["password"])
        torrent_infohashes = [torrent.get("hash") for torrent in qb.torrents()]  # type: ignore
        qb.reannounce(torrent_infohashes)