#!/usr/bin/env python3

from datetime import datetime
import json
import re
import logging
from pathlib import Path

import configargparse

import discord
from discord.ext import tasks
from discord import app_commands

from arkhamdb import ArkhamDBClient, ArkhamDBDeck
from validate_decks import Validator


class ArkhamDBUpdater(discord.Client):
    channel_list_file: Path
    channel_list: set[int]
    arkhamdb_client: ArkhamDBClient

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

        self.channel_list_file = channel_list_file

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

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

    async def setup_commands(self) -> None:
        tree = app_commands.CommandTree(self)

        @tree.command()
        async def adbmonitor(interaction: discord.Interaction) -> None:
            """Watch this channel for deck links and link to latest versions"""
            await interaction.response.send_message(
                "Now monitoring this channel for deck IDs", ephemeral=True
            )
            logging.info(f"Now monitoring: {self.get_channel(interaction.channel_id)}")
            self.channel_list.add(interaction.channel_id)
            with open(self.channel_list_file, "w") as f:
                json.dump(list(self.channel_list), f)

        @tree.command()
        async def adbforget(interaction: discord.Interaction) -> None:
            """Remove this channel from the monitor list"""
            await interaction.response.send_message(
                "No longer monitoring this channel for deck IDs", ephemeral=True
            )
            logging.info(
                f"Stopped monitoring: {self.get_channel(interaction.channel_id)}"
            )
            self.channel_list.discard(interaction.channel_id)
            with open(self.channel_list_file, "w") as f:
                json.dump(list(self.channel_list), f)

        await tree.sync()

    async def on_ready(self) -> None:
        self.arkhamdb_client = ArkhamDBClient()

        logging.info(f"Logged in as {self.user} (ID: {self.user.id})")
        expected_permissions = permissions = discord.Permissions(
            read_messages=True,
            read_message_history=True,
            send_messages=True,
            use_application_commands=True,
        )
        logging.info(
            "Invite URL: "
            + discord.utils.oauth_url(self.user.id, permissions=expected_permissions)
        )

        logging.info("Enabled on servers:")
        async for guild in self.fetch_guilds(limit=150):
            logging.info(f"  - {guild.name}")
        logging.info("------")

        for channel_id in self.channel_list:
            channel = self.get_channel(channel_id)
            permissions = channel.permissions_for(channel.guild.me)
            missing_permissions = (
                permissions & expected_permissions
            ) ^ expected_permissions
            if missing_permissions.value:
                logging.warning(
                    f"channel: '{channel}' missing permissions: {missing_permissions}"
                )
            else:
                logging.info(f"channel '{channel}' permissions OK")
            logging.debug(f"channel '{channel}' permissions: {dict(permissions)}")

        await self.setup_commands()

        # 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 = []
        if deck["xp"] is not None:
            unspent_xp = deck["xp"] - (deck["xp_spent"] or 0)
            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:
        logging.info(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
            )

            # TODO: caching
            cards = await self.arkhamdb_client.get_cards(encounter=True)
            validator = Validator(cards)
            validation_errors = list(
                validator.validate([deck for _, deck in latest_decks.values()])
            )
            if validation_errors:
                data = "\n".join(validation_errors)
                message_embed.add_field(
                    name="Card overuse:",
                    value=(data[:1020] + "\n...") if len(data) > 1024 else data,
                )

            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.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)


def main():
    parser = configargparse.ArgParser(
        description="A Discord bot for ArkhamDB deck info.",
        default_config_files=["./arkhamdb_discord_bot.conf"],
    )
    parser.add(
        "--channel_list",
        required=True,
        type=Path,
        help="path to a json file to store channel info",
    )
    parser.add("-c", "--config", is_config_file=True, help="config file path")
    parser.add(
        "--discord_token",
        required=True,
        help="Discord API token",
        env_var="DISCORD_TOKEN",
    )
    parser.add(
        "-d",
        "--debug",
        help="Print lots of debugging statements",
        action="store_const",
        dest="loglevel",
        const=logging.DEBUG,
        default=logging.WARNING,
    )
    parser.add_argument(
        "-v",
        "--verbose",
        help="Be verbose",
        action="store_const",
        dest="loglevel",
        const=logging.INFO,
    )
    args = parser.parse_args()

    logging.basicConfig(level=args.loglevel)

    intents = discord.Intents.default()
    intents.message_content = True

    bot = ArkhamDBUpdater(
        channel_list_file=args.channel_list,
        intents=intents,
    )
    bot.run(args.discord_token, reconnect=True)


if __name__ == "__main__":
    main()