#!/usr/bin/env python3

from datetime import datetime
import json
import re

import discord
from discord.ext import commands, tasks

from arkhamdb import ArkhamDBClient, ArkhamDBDeck
from validate_decks import Validator
from secret import TOKEN


class ArkhamDBUpdater(commands.Bot):
    channel_list: set[int]
    arkhamdb_client: ArkhamDBClient

    def __init__(self, *args, **kwargs) -> None:
        super().__init__(*args, **kwargs)

        # TODO: should really be a database
        with open("channel_list.json") as f:
            self.channel_list = set(json.load(f))

        self.arkhamdb_client = ArkhamDBClient()
        self.setup_commands()

    async def close(self) -> None:
        await self.arkhamdb_client.close()
        await super().close()

    def setup_commands(self) -> None:
        @self.command(name="monitor")
        async def monitor(ctx: commands.Context) -> None:
            """Watch this channel for deck links and link to latest versions."""
            await ctx.message.reply(
                "Now monitoring this channel for deck IDs", mention_author=True
            )
            self.channel_list.add(ctx.message.channel.id)
            with open("channel_list.json", "w") as f:
                json.dump(list(self.channel_list), f)

        @self.command(name="forget")
        async def forget(ctx: commands.Context) -> None:
            """Remove this channel from the monitor list"""
            await ctx.message.reply(
                "No longer monitoring this channel for deck IDs", mention_author=True
            )
            self.channel_list.discard(ctx.message.channel.id)
            with open("channel_list.json", "w") as f:
                json.dump(list(self.channel_list), f)

    async def on_ready(self) -> None:
        print(f"Logged in as {self.user} (ID: {self.user.id})")
        print("Enabled on servers:")
        async for guild in self.fetch_guilds(limit=150):
            print("  -", guild.name)
        print("------")

        self.arkhamdb_monitor.start()

    async def gather_deck_ids(self, channel: discord.TextChannel) -> dict[int, str]:
        deck_ids: dict[int, str] = {}
        url_regex = re.compile(
            r"(?P<prefix>.*)"
            + self.arkhamdb_client.origin
            + r"/deck/view/(?P<deck_id>\d+)"
        )
        async for message in channel.history(limit=200, oldest_first=True):
            # ignore the bot's messages
            if message.author.id == self.user.id:
                continue

            matches = url_regex.finditer(message.content)
            for match in matches:
                deck_ids[int(match.group("deck_id"))] = match.group("prefix")

        return deck_ids

    async def clear_old_messages(self, channel: discord.TextChannel) -> None:
        async for message in channel.history(limit=200):
            if (
                message.author.id == self.user.id
                and message.id != channel.last_message_id
                and len(message.embeds) == 1
            ):
                await message.delete()

    def status_for_deck(self, prefix: str, deck: ArkhamDBDeck) -> str:
        url = f"{self.arkhamdb_client.origin}/deck/view/{deck['id']}"
        status = f"{prefix}[{deck['name']}]({url}) [{deck['id']}]"

        issues = []
        unspent_xp = deck["xp"] - deck["xp_spent"]
        if unspent_xp > 0:
            issues.append(f"{unspent_xp} unspent XP")
        if deck["problem"] is not None:
            issues.append(deck["problem"])

        if issues:
            status += f"***{', '.join(issues)}***"

        return status

    async def update_channel_latest_decks(self, channel: discord.TextChannel) -> None:
        print(f"Running update in channel {channel.guild} - {channel.name}")
        async with channel.typing():
            deck_ids = await self.gather_deck_ids(channel)
            latest_decks = await self.arkhamdb_client.get_latest_decks(deck_ids)

            await self.clear_old_messages(channel)

            try:
                last_message = await channel.fetch_message(channel.last_message_id)
            except discord.NotFound:
                last_message = None

            message_text = "\n".join(
                self.status_for_deck(prefix, deck)
                for prefix, deck in latest_decks.values()
            )

            message_embed = discord.Embed(
                title=f"Updated as of {datetime.now()}", description=message_text
            )

            cards = await self.arkhamdb_client.get_cards()
            validator = Validator(cards)
            validation_errors = list(
                validator.validate([deck for _, deck in latest_decks.values()])
            )
            if validation_errors:
                message_embed.add_field(
                    name="Card overuse:", value="\n".join(validation_errors)
                )

            if (
                last_message is not None
                and last_message.author.id == self.user.id
                and len(last_message.embeds) == 1
            ):
                if (
                    message_embed.description != last_message.embeds[0].description
                    or message_embed.fields != last_message.embeds[0].fields
                ):
                    await last_message.edit(embed=message_embed)
            else:
                await channel.send(embed=message_embed)

    async def maybe_update_channel_for_message(self, message: discord.Message) -> None:
        # don't to react to the bot's changes, and only update registered channels
        if (
            message.author.id != self.user.id
            and message.channel.id in self.channel_list
        ):
            await self.update_channel_latest_decks(message.channel)

    async def on_message(self, message: discord.Message) -> None:
        await self.process_commands(message)
        await self.maybe_update_channel_for_message(message)

    async def on_message_edit(
        self, before: discord.Message, after: discord.Message
    ) -> None:
        await self.maybe_update_channel_for_message(after)

    async def on_message_delete(self, message: discord.Message) -> None:
        await self.maybe_update_channel_for_message(message)

    @tasks.loop(hours=1)
    async def arkhamdb_monitor(self) -> None:
        for channel_id in self.channel_list:
            channel = self.get_channel(channel_id)
            await self.update_channel_latest_decks(channel)


bot = ArkhamDBUpdater(command_prefix="!arkhamdb ")
bot.run(TOKEN, reconnect=True)