import twitchio

from meta import Bot

from ..customcmd.client import ExecClient
from ..customcmd.data import CustomCmd, CustomCmdData

from .context import CustomContext, CustomCmdUser


class TwitchCmdClient(ExecClient):
    def __init__(self, bot: Bot, data: CustomCmdData):
        super().__init__()
        self.bot = bot
        self.data = data

    async def process_message(self, message: twitchio.ChatMessage):
        # Check the prefixes in this community
        # Or get the 'possible' prefixes in this context, which should be mostly cached
        prefixes = await self.get_prefixes(message)
        prefixes = sorted(prefixes, key=len, reverse=True)

        content = message.text
        if message.reply:
            # Strip the hidden  mention prefix from the start of the message
            prefix = message.reply.parent_user.mention
            content = content[len(prefix) + 1 :]

        # If we start with a valid prefix, parse out a command name
        if prefix := next((p for p in prefixes if content.startswith(p)), None):
            # Strip the valid prefix
            content = content[len(prefix) :].strip()
            if not content:
                # Exit early, no command
                return

            # Extract possible command word
            maybe_command, *args = content.split()
            maybe_command = maybe_command.lower()

            # Lookup command words in this community (cache?)
            comm = await self.bot.profiles.fetch_community(message.broadcaster)
            cmdmap = await self.get_commands_in(comm.communityid)

            if cmd := cmdmap.get(maybe_command):
                # We now finally have a command.
                # Read the arguments, build the context, run the command.
                # TODO: Check the permissions and log etc.
                # TODO: Exception handling, as usual
                # TODO: Nice string reprs
                ctx = CustomContext(
                    bot=self.bot,
                    args=args,
                    alias=maybe_command,
                    used_prefix=prefix,
                    message=message,
                    initial_globals={
                        "author": CustomCmdUser(message.chatter),
                        "channel": CustomCmdUser(message.broadcaster),
                    },
                )
                result = await self.run_command(ctx, cmd.response)
                if result:
                    await message.broadcaster.send_message(result, sender=self.bot.user)

    async def get_prefixes(self, message: twitchio.ChatMessage):
        # TODO:
        return ("!",)

    async def get_commands_in(self, communityid: int) -> dict[str, CustomCmd]:
        """
        Get the custom commands in this community.

        Returns a map of {alias -> CustomCommand}
        """
        # TODO: Alias support
        commands = await CustomCmd.fetch_where(communityid=communityid)
        return {cmd.name: cmd for cmd in commands}