# -*- coding: utf-8 -*-
#
# Copyright © 2012 - 2020 Michal Čihař <michal@cihar.com>
#
# This file is part of Weblate <https://weblate.org/>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.
#

from __future__ import absolute_import, unicode_literals

import os
import subprocess
import time

from celery.schedules import crontab
from django.conf import settings
from django.core.cache import cache
from django.core.management.commands import diffsettings

from weblate.celery import app
from weblate.trans.util import get_clean_env
from weblate.utils.data import data_dir


@app.task(trail=False)
def ping():
    return None


@app.task(trail=False)
def heartbeat():
    cache.set('celery_heartbeat', time.time())


def ensure_backup_dir():
    backup_dir = data_dir("backups")
    if not os.path.exists(backup_dir):
        os.makedirs(backup_dir)


@app.task(trail=False)
def settings_backup():
    ensure_backup_dir()
    filename = data_dir("backups", "settings.py")
    command = diffsettings.Command()
    kwargs = {"default": None, "all": False}
    # Needed for Django 1.11 compatibility
    if hasattr(command, "output_hash"):
        kwargs["output"] = "hash"
    with open(filename, "w") as handle:
        handle.write(command.handle(**kwargs))


@app.task(trail=False)
def database_backup():
    ensure_backup_dir()
    database = settings.DATABASES["default"]
    if database["ENGINE"] != "django.db.backends.postgresql":
        return
    cmd = [
        "pg_dump",
        "--dbname",
        database["NAME"],
    ]
    if database["HOST"]:
        cmd += ["--host", database["HOST"]]
    if database["PORT"]:
        cmd += ["--port", database["PORT"]]
    if database["USER"]:
        cmd += ["--username", database["USER"]]
    if settings.DATABASE_BACKUP == "compressed":
        cmd += ["--file", data_dir("backups", "database.sql.gz")]
        cmd += ["--compress", "6"]
    else:
        cmd += ["--file", data_dir("backups", "database.sql")]

    subprocess.check_call(cmd, env=get_clean_env({"PGPASSWORD": database["PASSWORD"]}))


@app.on_after_finalize.connect
def setup_periodic_tasks(sender, **kwargs):
    sender.add_periodic_task(
        crontab(hour=1, minute=0), settings_backup.s(), name="settings-backup"
    )
    if settings.DATABASE_BACKUP != "none":
        sender.add_periodic_task(
            crontab(hour=1, minute=30), database_backup.s(), name="database-backup"
        )
    sender.add_periodic_task(60, heartbeat.s(), name="heartbeat")
