# -*- coding: utf-8 -*-
from debian import deb822
from pkg_resources import parse_version
from twisted.internet.defer import inlineCallbacks

from globaleaks import __version__
from globaleaks.handlers.admin.node import db_admin_serialize_node
from globaleaks.handlers.admin.notification import db_get_notification
from globaleaks.handlers.admin.user import db_get_users
from globaleaks.jobs.job import HourlyJob
from globaleaks.models.config import ConfigFactory
from globaleaks.orm import transact
from globaleaks.rest.cache import Cache
from globaleaks.utils.agent import get_page
from globaleaks.utils.log import log

DEB_PACKAGE_URL = b'https://deb.globaleaks.org/bullseye/Packages'


@transact
def evaluate_update_notification(session, state, latest_version):
    priv_fact = ConfigFactory(session, 1)

    stored_latest = priv_fact.get_val('latest_version')

    # Check if the running version is lower than the latest version
    if parse_version(stored_latest) >= parse_version(latest_version):
        return

    Cache.invalidate()

    priv_fact.set_val('latest_version', latest_version)

    # Check to reduce number of email notifications of new updates
    if parse_version(__version__) != parse_version(stored_latest):
        return

    for user_desc in db_get_users(session, 1, 'admin'):
        if not user_desc['notification']:
            continue

        lang = user_desc['language']
        template_vars = {
            'type': 'software_update_available',
            'latest_version': latest_version,
            'node': db_admin_serialize_node(session, 1, lang),
            'notification': db_get_notification(session, 1, lang),
            'user': user_desc,
        }

        state.format_and_send_mail(session, 1, user_desc['mail_address'], template_vars)


class UpdateCheck(HourlyJob):
    interval = 60*60*24

    def fetch_packages_file(self):
        return get_page(self.state.get_agent(), DEB_PACKAGE_URL)

    @inlineCallbacks
    def operation(self):
        try:
            log.debug('Fetching latest GlobaLeaks version from repository')
            packages_file = yield self.fetch_packages_file()
            packages_file = packages_file.decode()
            versions = [p['Version'] for p in deb822.Deb822.iter_paragraphs(packages_file) if p['Package'] == 'globaleaks']
            versions.sort(key=parse_version)

            latest_version = versions[-1]

            if not self.state.tenants[1].cache.notification.disable_admin_notification_emails:
                yield evaluate_update_notification(self.state, latest_version)

            log.debug('The newest version in the repository is: %s', latest_version)
        except:
            pass