python-app-rocketbot/cogs/urlspamcog.py

from discord import Guild, Message
from discord.ext import commands
import re
from datetime import timedelta

from cogs.basecog import BaseCog
from config import CONFIG
from storage import Storage

class URLSpamCog(BaseCog):
	CONFIG_KEY_EARLY_URL_TIMEOUT = "urlspam_early_url_timeout"
	CONFIG_KEY_EARLY_URL_ACTION = "urlspam_early_url_action"

	def __init__(self, bot):
		super().__init__(bot)

	def __early_url_timeout(self, guild: Guild) -> int:
		return Storage.get_config_value(guild, self.CONFIG_KEY_EARLY_URL_TIMEOUT) or \
			self.get_cog_default('early_url_timeout')

	def __early_url_action(self, guild: Guild) -> str:
		return Storage.get_config_value(guild, self.CONFIG_KEY_EARLY_URL_ACTION) or \
			self.get_cog_default('early_url_action')

	@commands.Cog.listener()
	async def on_message(self, message: Message):
		if message.guild is None or message.channel is None:
			# DM or something
			return
		action = self.__early_url_action(message.guild)
		if action == 'nothing':
			return
		if message.author.permissions_in(message.channel).ban_members:
			# Mods are exempt
			return
		if not self.__contains_url(message.content):
			return
		join_age = message.created_at - message.author.joined_at
		join_age_str = self.__format_timedelta(join_age)
		if join_age.total_seconds() < self.__early_url_timeout(message.guild):
			if action == 'modwarn':
				await self.warn(message.guild, f'User {message.author.mention} ' +
					f'posted a URL {join_age_str} after joining.\n\n> {message.content}')
				# TODO: Emoji actions
			elif action == 'delete':
				await message.delete()
				# TODO: Info to mods
			elif action == 'kick':
				await message.author.kick(reason=f'User posted a link {join_age_str} after joining')
				# TODO: Info to mods
			elif action == 'ban':
				await message.author.ban(reason=f'User posted a link {join_age_str} after joining', delete_message_days=1)
				# TODO: Info to mods

	def __contains_url(self, text: str) -> bool:
		p = re.compile(r'http(?:s)?://[^\s]+')
		return p.search(text) is not None

	def __format_timedelta(self, timespan: timedelta) -> str:
		parts = []
		d = timespan.days
		h = timespan.seconds // 3600
		m = (timespan.seconds // 60) % 60
		s = timespan.seconds % 60
		if d > 0:
			parts.append(f'{d} days')
		if d > 0 or h > 0:
			parts.append(f'{h} hours')
		if d > 0 or h > 0 or m > 0:
			parts.append(f'{m} minutes')
		parts.append(f'{s} seconds')
		# Limit the precision to the two most significant elements
		while len(parts) > 2:
			parts.pop(-1)
		return ' '.join(parts)