import datetime
from time import sleep

from helpers import now
from helpers.mongo import mongo
from helpers.ruz import ruz
from settings import MOSCOW_TIMEZONE


def fetch_schedule_for_user(user_hse_id: int):
    today = now()
    next_day = today + datetime.timedelta(days=7)
    schedule = ruz.get_schedule(user_hse_id, today, next_day)
    if schedule is None:
        return False
    saved_ids = []
    for element in schedule:
        year, month, day = element['date'].split('.')
        begin_hour, begin_minute = element['beginLesson'].split(':')
        end_hour, end_minute = element['endLesson'].split(':')
        lesson = mongo.lessons_collection.find_one({
            "discipline": element['discipline'],
            "auditorium": element['auditorium'],
            "hse_user_id": user_hse_id,
            "begin": datetime.datetime(
                year=int(year),
                month=int(month),
                day=int(day),
                hour=int(begin_hour),
                minute=int(begin_minute),
            )
        })
        if lesson is None:
            result = mongo.lessons_collection.insert_one({
                "discipline": element['discipline'],
                "auditorium": element['auditorium'],
                "hse_user_id": user_hse_id,
                "begin": datetime.datetime(
                    year=int(year),
                    month=int(month),
                    day=int(day),
                    hour=int(begin_hour),
                    minute=int(begin_minute),
                ),
                "end": datetime.datetime(
                    year=int(year),
                    month=int(month),
                    day=int(day),
                    hour=int(end_hour),
                    minute=int(end_minute),
                ),
                "building": element['building'],
                "lecturer": element['lecturer'],
                "notified": False
            })
            saved_ids.append(result.inserted_id)
        else:
            saved_ids.append(lesson['_id'])
    mongo.lessons_collection.delete_many({"hse_user_id": user_hse_id, "_id": {"$nin": saved_ids}})
    return True


def process():
    for user in mongo.users_collection.find({"hse_id": {"$ne": None}}):
        fetch_schedule_for_user(user['hse_id'])


def delete_old():
    mongo.lessons_collection.delete_many({"end": {"$lte": now() - datetime.timedelta(days=1)}})


def fetch():
    while True:
        print("fetch start")
        begin = datetime.datetime.now()
        process()
        end = datetime.datetime.now()
        print('fetch finished')
        print("time elapsed", (end - begin).total_seconds())
        delete_old()
        sleep(60 * 60)