"""Defines the daily loop that runs the Dakiny bot functions."""

import random
from datetime import UTC, datetime, time
from typing import TYPE_CHECKING

from nextcord.ext import commands, tasks
from pytz import timezone
from sqlalchemy import select
from sqlalchemy.orm import Session

from classes.election import Election
from DakinySettings import settings
from database_setup.sql_data_classes import UserBirthday, engine
from main import birthday_list
from utils import get_current_election_cycle

if TYPE_CHECKING:
    import nextcord

KANDY = 239547993106284544


class DailyLoop(commands.Cog, name="Daily Loop"):
    """Class for performing daily functions."""

    def __init__(self, bot: commands.Bot) -> None:
        self.bot = bot
        self.current_election = None
        self.update_birthdays()

        # pylint doesn't recognize that daily_loop is subclassed from tasks.loop.
        self.daily_loop.start()  # pylint: disable=no-member

    @tasks.loop(time=time(hour=0, tzinfo=timezone("UTC")))
    async def daily_loop(self) -> None:
        """
        Runs daily.

        Checks if the current election is None. If so, checks if there is an active election. If there is
        an active election, runs the check_date() function for the election to perform actions. Finally checks if the
        election is over to delete the current election object.
        """
        if self.current_election is None:
            self.current_election = self.get_election()

        if self.current_election is not None:
            await self.current_election.check_date()
            if self.current_election.election_over:
                self.current_election = None

        self.update_birthdays()

        if KANDY in birthday_list:
            # inform kandy that it is her "birthday"
            kandy: nextcord.User = await self.bot.fetch_user(KANDY)
            await kandy.send('Happy "Birthday"!')

        await self.cakedays()

    @daily_loop.before_loop
    async def before_loop(self) -> None:
        """Actions run before the loop starts. Want to wait for bot to be ready and get the current cycle."""
        await self.bot.wait_until_ready()

        # Bot needs to know guilds to get the current cycle.
        self.current_election = self.get_election()

    def get_election(self) -> Election:
        """
        Creates an object for the current election cycle if one is active.

        An election is considered active between the election start and the term start.

        Returns:
            Election: Current election cycle, None if there is no election happening.
        """
        cycle = get_current_election_cycle()

        # prevent exception from using cycle as an Int in an array
        if cycle is None:
            return None

        return Election(cycle, self.bot.get_guild(settings.params.guild_id))

    def update_birthdays(self) -> None:
        """Goes through database to collect all birthdays that are today. Adds user's id to birthday list."""
        birthday_list.clear()

        # kandy's 1% chance
        if random.randint(0, 99) == 0:  # noqa: S311 isn't cryptography related.
            birthday_list.append(KANDY)

        today = datetime.now(tz=UTC).date()
        birthday = f"{today.month}/{today.day}"

        stmt = select(UserBirthday.UserId).where(UserBirthday.Birthday == birthday)
        with Session(engine) as session:
            to_add = session.scalars(stmt)
            birthday_list.extend(to_add.all())

    async def cakedays(self) -> None:
        """
        Loops through the guild's humans checking for joined_at dates that match today's date.

        Sends a message saying happy cakeday.
        """
        today = datetime.now(tz=UTC).date()
        guild: nextcord.Guild = self.bot.get_guild(settings.params.guild_id)
        announce_channel: nextcord.TextChannel = guild.get_channel(settings.channel_ids.general)

        cakedays: list[nextcord.Member] = [
            human for human in guild.humans if human.joined_at.month == today.month and human.joined_at.day == today.day
        ]

        for member in cakedays:
            years = today.year - member.joined_at.year
            year_str = "years" if years > 1 else "year"
            msg = f"Happy Cake day! <@{member.id}> joined the discord {years} {year_str} ago!"
            await announce_channel.send(msg)