###################################################################################
#
#    Copyright (c) 2017-2019 MuK IT GmbH.
#
#    This file is part of MuK Session Store
#    (see https://mukit.at).
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU Lesser 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 Lesser General Public License for more details.
#
#    You should have received a copy of the GNU Lesser General Public License
#    along with this program. If not, see <http://www.gnu.org/licenses/>.
#
###################################################################################

import logging
import random

from odoo import http, tools
from odoo.addons.muk_session_store.store.postgres import PostgresSessionStore
from odoo.addons.muk_session_store.store.redis import RedisSessionStore
from odoo.addons.muk_utils.tools.patch import monkey_patch
from odoo.http import request
from odoo.tools.func import lazy_property

_logger = logging.getLogger(__name__)

try:
    import redis
except ImportError:
    if tools.config.get("session_store_redis"):
        _logger.warning("The Python library redis is not installed.")
    redis = False


def get_session_store_database():
    return tools.config.get("session_store_dbname", "session_store")


@monkey_patch(http)
def db_monodb(httprequest=None):
    if tools.config.get("session_store_database"):
        httprequest = httprequest or request.httprequest
        dbs = http.db_list(True, httprequest)
        store = get_session_store_database()
        db_session = httprequest.session.db
        if db_session in dbs:
            return db_session
        if store in dbs:
            dbs.remove(store)
        if len(dbs) == 1:
            return dbs[0]
        return None
    else:
        return db_monodb.super(httprequest)


@monkey_patch(http)
def db_filter(dbs, httprequest=None):
    dbs = db_filter.super(dbs, httprequest=httprequest)
    store = get_session_store_database()
    if store in dbs:
        dbs.remove(store)
    return dbs


@monkey_patch(http)
def session_gc(session_store):
    if tools.config.get("session_store_database"):
        if random.random() < 0.001:
            session_store.clean()
    elif tools.config.get("session_store_redis"):
        pass
    else:
        session_gc.super(session_store)


class Root(http.Root):
    @lazy_property
    def session_store(self):
        if tools.config.get("session_store_database"):
            return PostgresSessionStore(session_class=http.OpenERPSession)
        elif tools.config.get("session_store_redis") and redis:
            return RedisSessionStore(session_class=http.OpenERPSession)
        return super(Root, self).session_store


http.root = Root()