from discord import Guild, Message, TextChannel
from discord.ext import commands

from storage import StateKey, Storage

class BaseCog(commands.Cog):
	def __init__(self, bot):
		self.bot = bot

	@classmethod
	def save_setting(cls, guild: Guild, name: str, value):
		"""
		Saves one value to a guild's persisted state. The given value must
		be a JSON-encodable type.
		"""
		if value is not None and not isinstance(value, (bool, int, float, str, list, dict)):
			raise Exception(f'value for key {name} is not supported JSON type! {type(value)}')
		state: dict = Storage.state_for_guild(guild)
		if value is None:
			del state[name]
		else:
			state[name] = value
		Storage.save_guild_state(guild)

	@classmethod
	async def warn(cls, guild: Guild, message: str) -> bool:
		"""
		Sends a warning message to the configured warning channel for the
		given guild. If no warning channel is configured no action is taken.
		Returns True if the message was sent successfully or False if the
		warning channel could not be found.
		"""
		state: dict = Storage.state_for_guild(guild)
		channel_id = state.get(StateKey.WARNING_CHANNEL_ID)
		if channel_id is None:
			cls.guild_trace(guild, 'No warning channel set! No warning issued.')
			return False
		channel: TextChannel = guild.get_channel(channel_id)
		if channel is None:
			cls.guild_trace(guild, 'Configured warning channel no longer exists!')
			return False
		message: Message = await channel.send(message)
		return message is not None

	@classmethod
	def guild_trace(cls, guild: Guild, message: str) -> None:
		print(f'[guild {guild.id}|{guild.name}] {message}')