from django.conf import settings
from django.utils import timezone
from django.core.management.base import BaseCommand
from django.db import close_old_connections

import time
import signal
import sys
import traceback
from datetime import timedelta

from torrent.models import Torrent
from torrent.utils import transmission_handler
from app.utils import send_sync_channel_message


def update_transmission_data():
    data = transmission_handler.get_all_data()

    updated_torrents = []
    for torrent in Torrent.objects.all():
        if torrent.id in data and torrent.transmission_data != data[torrent.id]:
            torrent.transmission_data = data[torrent.id]
            updated_torrents.append(torrent)
    if updated_torrents:
        Torrent.objects.bulk_update(updated_torrents, ["transmission_data"])
        send_sync_channel_message("torrent", "transmission_data_updated", {
            torrent.id: torrent.transmission_data
            for torrent in updated_torrents
        })


def clean_old_torrents():
    expired_date = timezone.now() - timedelta(days=settings.TORRENT_TTL)
    Torrent.objects.filter(date_created__lt=expired_date).first().delete()


class Command(BaseCommand):
    task_schedule = {
        "update_transmission_data": {
            "func": update_transmission_data,
            "schedule": 5.0
        },
        "clean_old_torrents": {
            "func": clean_old_torrents,
            "schedule": 60.0
        }
    }
    histories = {}
    run = True

    def handle(self, *args, **options):
        signal.signal(signal.SIGINT, self.exit_gracefully)
        signal.signal(signal.SIGTERM, self.exit_gracefully)

        self.stdout.write(self.style.SUCCESS("start"))
        while self.run:
            for name, task in self.task_schedule.items():
                if name not in self.histories or time.time() - self.histories[name] > task["schedule"]:
                    self.call_func(name)
            time.sleep(1)

    def exit_gracefully(self, signum, frame):
        self.stdout.write(self.style.SUCCESS("exit"))
        self.run = False

    def call_func(self, name):
        close_old_connections()
        try:
            self.task_schedule[name]["func"]()
            self.histories[name] = time.time()
        except Exception as e:
            tb = traceback.format_exc()
            self.stderr.write(self.style.ERROR(f"Error in {name}: {e}\n{tb}"))