import pathlib
from typing import List

import yaml
from redbot.cogs.trivia import LOG
from redbot.cogs.trivia.trivia import InvalidListError, Trivia
from redbot.core import commands
from redbot.core.bot import Red
from redbot.core.data_manager import cog_data_path
from redbot.core.utils import box

from .audiosession import AudioSession


class AudioTrivia(Trivia):
    """
    Custom commands
    Creates commands used to display text and adjust roles
    """

    def __init__(self, bot: Red):
        super().__init__()
        self.bot = bot
        self.audio = None

    @commands.group(invoke_without_command=True)
    @commands.guild_only()
    async def audiotrivia(self, ctx: commands.Context, *categories: str):
        """Start trivia session on the specified category.

                You may list multiple categories, in which case the trivia will involve
                questions from all of them.
                """
        if not categories and ctx.invoked_subcommand is None:
            await ctx.send_help()
            return

        if self.audio is None:
            self.audio = self.bot.get_cog("Audio")

        if self.audio is None:
            await ctx.send("Audio is not loaded. Load it and try again")
            return

        categories = [c.lower() for c in categories]
        session = self._get_trivia_session(ctx.channel)
        if session is not None:
            await ctx.send("There is already an ongoing trivia session in this channel.")
            return
        trivia_dict = {}
        authors = []
        for category in reversed(categories):
            # We reverse the categories so that the first list's config takes
            # priority over the others.
            try:
                dict_ = self.get_audio_list(category)
            except FileNotFoundError:
                await ctx.send(
                    "Invalid category `{0}`. See `{1}audiotrivia list`"
                    " for a list of trivia categories."
                    "".format(category, ctx.prefix)
                )
            except InvalidListError:
                await ctx.send(
                    "There was an error parsing the trivia list for"
                    " the `{}` category. It may be formatted"
                    " incorrectly.".format(category)
                )
            else:
                trivia_dict.update(dict_)
                authors.append(trivia_dict.pop("AUTHOR", None))
                continue
            return
        if not trivia_dict:
            await ctx.send(
                "The trivia list was parsed successfully, however it appears to be empty!"
            )
            return
        settings = await self.conf.guild(ctx.guild).all()
        config = trivia_dict.pop("CONFIG", None)
        if config and settings["allow_override"]:
            settings.update(config)
        settings["lists"] = dict(zip(categories, reversed(authors)))
        session = AudioSession.start(ctx, trivia_dict, settings, self.audio)
        self.trivia_sessions.append(session)
        LOG.debug("New audio trivia session; #%s in %d", ctx.channel, ctx.guild.id)

    @audiotrivia.command(name="list")
    @commands.guild_only()
    async def audiotrivia_list(self, ctx: commands.Context):
        """List available trivia categories."""
        lists = set(p.stem for p in self._audio_lists())

        msg = box("**Available trivia lists**\n\n{}".format(", ".join(sorted(lists))))
        if len(msg) > 1000:
            await ctx.author.send(msg)
            return
        await ctx.send(msg)

    def get_audio_list(self, category: str) -> dict:
        """Get the audiotrivia list corresponding to the given category.

        Parameters
        ----------
        category : str
            The desired category. Case sensitive.

        Returns
        -------
        `dict`
            A dict mapping questions (`str`) to answers (`list` of `str`).

        """
        try:
            path = next(p for p in self._audio_lists() if p.stem == category)
        except StopIteration:
            raise FileNotFoundError("Could not find the `{}` category.".format(category))

        with path.open(encoding="utf-8") as file:
            try:
                dict_ = yaml.load(file)
            except yaml.error.YAMLError as exc:
                raise InvalidListError("YAML parsing failed.") from exc
            else:
                return dict_

    def _audio_lists(self) -> List[pathlib.Path]:
        personal_lists = [p.resolve() for p in cog_data_path(self).glob("*.yaml")]

        return personal_lists + get_core_lists()


def get_core_lists() -> List[pathlib.Path]:
    """Return a list of paths for all trivia lists packaged with the bot."""
    core_lists_path = pathlib.Path(__file__).parent.resolve() / "data/lists"
    return list(core_lists_path.glob("*.yaml"))