# © 2018–2020 io mintz <io@mintz.cc>
#
# Emote Manager is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# Emote Manager is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with Emote Manager. If not, see <https://www.gnu.org/licenses/>.

import contextlib

import discord
from discord.ext import commands

class Meta(commands.Cog):
	# TODO does this need to be configurable?
	INVITE_DURATION_SECONDS = 60 * 60 * 3
	MAX_INVITE_USES = 5

	def __init__(self, bot):
		self.bot = bot
		self.support_channel = None
		self.task = bot.loop.create_task(self.cache_invite_channel())

	def cog_unload(self):
		self.task.cancel()

	async def cache_invite_channel(self):
		self.support_channel = ch = await self.bot.fetch_channel(self.bot.config['support_server_invite_channel'])
		return ch

	@commands.command()
	async def support(self, context):
		"""Directs you to the support server."""
		ch = self.support_channel or await self.cache_invite_channel()

		reason = f'Created for {context.author} (ID: {context.author.id})'
		invite = await ch.create_invite(
			max_age=self.INVITE_DURATION_SECONDS,
			max_uses=self.MAX_INVITE_USES,
			reason=reason,
		)

		try:
			await context.author.send(f'Official support server invite: {invite}')
		except discord.Forbidden:
			with contextlib.suppress(discord.HTTPException):
				await context.message.add_reaction(utils.SUCCESS_EMOJIS[True])
			with contextlib.suppress(discord.HTTPException):
				await context.send('Unable to send invite in DMs. Please allow DMs from server members.')
		else:
			try:
				await context.message.add_reaction('📬')
			except discord.HTTPException:
				with contextlib.suppress(discord.HTTPException):
					await context.send('📬')

	@commands.command(aliases=['inv'])
	async def invite(self, context):
		"""Gives you a link to add me to your server."""
		permissions = discord.Permissions()
		permissions.update(**dict.fromkeys((
			'read_messages',
			'send_messages',
			'add_reactions',
			'external_emojis',
			'manage_emojis',
			'embed_links',
			'attach_files',
		), True))

		await context.send('<%s>' % discord.utils.oauth_url(self.bot.user.id, permissions))

def setup(bot):
	bot.add_cog(Meta(bot))

	if not bot.config.get('support_server_invite_channel'):
		bot.remove_command('support')