"""Reaction handler with percentage-based triggers, cooldowns, and mention reactions."""

import asyncio
import logging
from typing import Optional

import discord
from discord.ext import commands

logger = logging.getLogger(__name__)

# ─── Configuration ───────────────────────────────────────────────────────────

REACTION_CHANCE = 0.05  # 5% chance to react to a message
REACTION_COOLDOWN = 60  # seconds per channel

# ─── Reaction Handler ────────────────────────────────────────────────────────


class ReactionHandler:
    """Handles message reactions with cooldowns and mention triggers."""

    def __init__(self, bot: commands.Bot) -> None:
        self.bot = bot
        self._cooldowns: dict[int, float] = {}  # channel_id -> next_available
        self._reaction_emojis: list[discord.Emoji] = []

    async def handle_reactions(self, message: discord.Message) -> None:
        """Check if a message should be reacted to and handle reactions."""
        channel_id = message.channel.id

        # Enforce cooldown
        now = discord.utils.utcnow().timestamp()
        if channel_id in self._cooldowns:
            if now < self._cooldowns[channel_id]:
                return

        # Check if message mentions the bot
        if self._is_mention(message):
            await self._handle_mention(message)
        else:
            # Random chance to react
            if self._should_react():
                await self._add_reaction(message)

        # Enforce cooldown
        self._cooldown(channel_id)

    def _is_mention(self, message: discord.Message) -> bool:
        """Check if the message mentions the bot."""
        return f"<@{self.bot.user.id}>" in message.content or f"<@!{self.bot.user.id}>" in message.content

    def _should_react(self) -> bool:
        """Determine if we should react (random chance)."""
        import random
        return random.random() < REACTION_CHANCE

    async def _handle_mention(self, message: discord.Message) -> None:
        """Handle a mention — react with a random emoji."""
        if self._reaction_emojis:
            emoji = self._reaction_emojis[0]
            try:
                await message.add_reaction(emoji)
            except discord.Forbidden:
                pass

    async def _add_reaction(self, message: discord.Message) -> None:
        """Add a reaction to a message."""
        if self._reaction_emojis:
            emoji = self._reaction_emojis[0]
            try:
                await message.add_reaction(emoji)
            except discord.Forbidden:
                pass

    def _cooldown(self, channel_id: int) -> None:
        """Set cooldown for a channel."""
        self._cooldowns[channel_id] = discord.utils.utcnow().timestamp() + REACTION_COOLDOWN

    def register_emoji(self, emoji: discord.Emoji) -> None:
        """Register an emoji for reactions."""
        self._reaction_emojis.append(emoji)


# ─── Bot Integration ─────────────────────────────────────────────────────────


async def setup(bot: commands.Bot) -> None:
    """Register the reaction handler with the bot."""
    handler = ReactionHandler(bot)

    @bot.event
    async def on_message(message: discord.Message) -> None:
        """Handle reactions on messages."""
        if message.author == bot.user:
            return

        if message.author.bot:
            return

        await handler.handle_reactions(message)


def register_emoji(bot: commands.Bot, emoji: discord.Emoji) -> None:
    """Register an emoji for reactions."""
    handler = ReactionHandler.__new__(ReactionHandler)
    handler.bot = bot
    handler._reaction_emojis = []
    bot._reaction_handler = handler