import datetime
from functools import cached_property

import pymongo

import settings
from helpers import now


class Mongo:
    def __init__(self):
        url = f"mongodb://{settings.MONGO_USER}:{settings.MONGO_PASSWORD}@{settings.MONGO_HOST}:27017/"
        self.client = pymongo.MongoClient(url)
        self.database = self.client.get_database("ruz-bot")
        self.users_collection.create_index([
            ("chat_id", 1)
        ])
        self.users_collection.create_index([
            ("notify_minutes", 1)
        ])
        self.users_collection.create_index([
            ("next_daily_notify_time", 1)
        ])
        self.lessons_collection.create_index([
            ("discipline", 1),
            ("auditorium", 1),
            ("begin", 1),
            ("user_email", 1),
            ("link", 1)
        ])
        self.lessons_collection.create_index([
            ("user_email", 1),
            ("begin", 1)
        ])
        self.lessons_collection.create_index([
            ("user_email", 1),
            ("begin", 1),
            ("notified", 1)
        ])


    def __getitem__(self, item):
        return self.database.get_collection(item)

    @cached_property
    def users_collection(self):
        return self["users"]

    @cached_property
    def lessons_collection(self):
        return self["lessons"]

    def _get_lessons_on_date(self, user: dict, date: datetime.datetime):
        date = datetime.datetime(year=date.year, month=date.month, day=date.day)
        next_date = date + datetime.timedelta(days=1)
        lessons = []
        for lesson in self.lessons_collection.find({
            "user_email": user['email'],
            "begin": {"$gte": date, "$lte": next_date}}
        ):
            lessons.append(lesson)
        lessons.sort(key=lambda les: les["begin"])
        return lessons

    def get_today_lessons(self, user: dict):
        return self._get_lessons_on_date(user, now(user))

    def get_tomorrow_lessons(self, user: dict):
        return self._get_lessons_on_date(user, now(user) + datetime.timedelta(days=1))

    def get_week_lessons(self, user: dict):
        date = now(user)
        date = datetime.datetime(year=date.year, month=date.month, day=date.day)
        weekday = date.weekday()
        next_date = date + datetime.timedelta(days=(6 - weekday))
        lessons = []
        for lesson in self.lessons_collection.find({
            "user_email": user['email'],
            "begin": {"$gte": date, "$lte": next_date}}
        ):
            lessons.append(lesson)
        lessons.sort(key=lambda les: les["begin"])
        return lessons


mongo = Mongo()