import importlib
import logging
from typing import Sequence, TYPE_CHECKING

from asyncirc.protocol import IrcProtocol
from irclib.parser import Message, Prefix

from .config import PluginConfig, ServerConfig

if TYPE_CHECKING:
    from .bot import Bot


log = logging.getLogger(__name__)


class Plugin:
    def __init__(self, bot: "Bot", plugin_config: PluginConfig):
        self.__plugin_config = plugin_config
        self.__bot = bot

    def get_message_types(self) -> Sequence[str]:
        """
        Gets the message types that this plugin listens for.

        This is usually going to be just PRIVMSG by itself, i.e. `["PRIVMSG"]`.
        However, if you want to handle different messages (such as PART, JOIN,
        KICK, etc) then you can change that here.
        """
        return ["PRIVMSG"]

    @property
    def channels(self) -> Sequence[str]:
        if "channels" in self.plugin_config:
            return self.plugin_config["channels"]
        else:
            return self.server_config.channels

    @property
    def enabled(self) -> bool:
        return self.plugin_config.get("enabled", True)

    @property
    def plugin_config(self) -> PluginConfig:
        return self.__plugin_config

    @property
    def bot(self) -> "Bot":
        return self.__bot

    @property
    def server_config(self) -> ServerConfig:
        return self.bot.server_config

    @property
    def nick(self) -> str:
        return self.server_config.nick

    def send_to(self, conn: IrcProtocol, who: str, message: str):
        message = Message(None, None, "PRIVMSG", who, message[:1024])
        self.send_message(conn, message)

    def send_message(self, conn: IrcProtocol, message: Message):
        conn.send(str(message))

    async def on_join(self, conn: IrcProtocol, channel: str, who: Prefix):
        pass

    async def on_part(self, conn: IrcProtocol, channel: str, who: Prefix):
        pass

    async def on_kick(self, conn: IrcProtocol, channel: str, who: Prefix):
        pass

    async def on_message(self, conn: IrcProtocol, channel: str, who: Prefix, line: str):
        pass

    async def on_load(self):
        pass

    async def on_connect(self, conn: IrcProtocol):
        pass

    async def on_unload(self, conn: IrcProtocol):
        pass


def load_plugin(bot: "Bot", plugin_config: PluginConfig) -> Plugin:
    name = plugin_config["module"]
    log.info("Loading plugin %s", name)
    plugin_module = importlib.import_module(name)
    PluginType = plugin_module.PLUGIN_TYPE
    return PluginType(bot, plugin_config)