from datetime import datetime
from typing import Dict, Any
from zoneinfo import ZoneInfo

from bson import ObjectId
from discord import (
    ApplicationContext,
    Attachment,
    SlashCommandGroup,
    option,
)
from discord.ext.commands import Cog
from discord.utils import basic_autocomplete

from classes import PycordEvent, PycordGuild
from classes.pycord_bot import PycordBot
from modules.database import col_events
from modules.utils import autocomplete_active_events


# TODO Move to staticmethod or to a separate module
async def validate_event_validity(
    ctx: ApplicationContext,
    name: str,
    start_date: datetime | None,
    finish_date: datetime | None,
    guild_timezone: ZoneInfo,
    event_id: ObjectId | None = None,
) -> None:
    if start_date > finish_date:
        # TODO Make a nice message
        await ctx.respond("Start date must be before finish date")
        return
    elif start_date < datetime.now(tz=guild_timezone):
        # TODO Make a nice message
        await ctx.respond("Start date must not be in the past")
        return

    query: Dict[str, Any] = {
        "name": name,
        "ended": None,
        "ends": {"$gt": datetime.now(tz=ZoneInfo("UTC"))},
        "cancelled": {"$ne": True},
    }

    if event_id is not None:
        query["_id"] = {"$ne": event_id}

    if (await col_events.find_one(query)) is not None:
        # TODO Make a nice message
        await ctx.respond("There can only be one active event with the same name")
        return


class Event(Cog):
    """Cog with event management commands."""

    def __init__(self, bot: PycordBot):
        self.bot: PycordBot = bot

    # TODO Introduce i18n
    command_group: SlashCommandGroup = SlashCommandGroup("event", "Event management")

    # TODO Introduce i18n
    @command_group.command(
        name="create",
        description="Create new event",
    )
    @option("name", description="Name of the event", required=True)
    @option("start", description="Date when the event starts (DD.MM.YYYY HH:MM)", required=True)
    @option("end", description="Date when the event ends (DD.MM.YYYY HH:MM)", required=True)
    @option("thumbnail", description="Thumbnail of the event", required=False)
    async def command_event_create(
        self,
        ctx: ApplicationContext,
        name: str,
        start: str,
        end: str,
        thumbnail: Attachment = None,
    ) -> None:
        guild: PycordGuild = await self.bot.find_guild(ctx.guild.id)

        if not guild.is_configured():
            # TODO Make a nice message
            await ctx.respond("Guild is not configured.")
            return

        guild_timezone: ZoneInfo = ZoneInfo(guild.timezone)

        try:
            start_date: datetime = datetime.strptime(start, "%d.%m.%Y %H:%M")
            end_date: datetime = datetime.strptime(end, "%d.%m.%Y %H:%M")

            start_date = start_date.replace(tzinfo=guild_timezone)
            end_date = end_date.replace(tzinfo=guild_timezone)
        except ValueError:
            # TODO Make a nice message
            await ctx.respond("Could not parse start and end dates.")
            return

        await validate_event_validity(ctx, name, start_date, end_date, guild_timezone)

        event: PycordEvent = await self.bot.create_event(
            name=name,
            guild_id=guild.id,
            creator_id=ctx.author.id,
            starts=start_date.astimezone(ZoneInfo("UTC")),
            ends=end_date.astimezone(ZoneInfo("UTC")),
            thumbnail_id=thumbnail.id if thumbnail else None,
        )

        # TODO Make a nice message
        await ctx.respond("Event has been created.")

    # TODO Introduce i18n
    @command_group.command(
        name="edit",
        description="Edit event",
    )
    @option(
        "event",
        description="Name of the event",
        autocomplete=basic_autocomplete(autocomplete_active_events),
        required=True,
    )
    @option("name", description="New name of the event", required=False)
    @option("start", description="Date when the event starts (DD.MM.YYYY HH:MM)", required=False)
    @option("end", description="Date when the event ends (DD.MM.YYYY HH:MM)", required=False)
    @option("thumbnail", description="Thumbnail of the event", required=False)
    async def command_event_edit(
        self,
        ctx: ApplicationContext,
        event: str,
        name: str = None,
        start: str = None,
        end: str = None,
        thumbnail: Attachment = None,
    ) -> None:
        guild: PycordGuild = await self.bot.find_guild(ctx.guild.id)
        pycord_event: PycordEvent = await self.bot.find_event(event_id=event)

        if pycord_event is None:
            # TODO Make a nice message
            await ctx.respond("Event was not found.")
            return

        if not guild.is_configured():
            # TODO Make a nice message
            await ctx.respond("Guild is not configured.")
            return

        guild_timezone: ZoneInfo = ZoneInfo(guild.timezone)

        try:
            start_date: datetime = (
                pycord_event.starts if start is None else datetime.strptime(start, "%d.%m.%Y %H:%M")
            )
            start_date = start_date.replace(tzinfo=guild_timezone)
        except ValueError:
            # TODO Make a nice message
            await ctx.respond("Could not parse the start date.")
            return

        try:
            end_date: datetime = (
                pycord_event.ends if end is None else datetime.strptime(end, "%d.%m.%Y %H:%M")
            )
            end_date = end_date.replace(tzinfo=guild_timezone)
        except ValueError:
            # TODO Make a nice message
            await ctx.respond("Could not parse the end date.")
            return

        await validate_event_validity(ctx, name, start_date, end_date, guild_timezone)

        await pycord_event.update(
            self.bot.cache,
            starts=start_date,
            ends=end_date,
            name=pycord_event.name if name is None else name,
            thumbnail_id=pycord_event.thumbnail_id if thumbnail is None else thumbnail.id,
        )

        # TODO Make a nice message
        await ctx.respond("Event has been updated.")

    # TODO Introduce i18n
    @command_group.command(
        name="cancel",
        description="Cancel event",
    )
    @option(
        "event",
        description="Name of the event",
        autocomplete=basic_autocomplete(autocomplete_active_events),
        required=True,
    )
    @option("confirm", description="Confirmation of the operation", required=False)
    async def command_event_cancel(
        self,
        ctx: ApplicationContext,
        event: str,
        confirm: bool = False,
    ) -> None:
        if confirm is None or not confirm:
            # TODO Make a nice message
            await ctx.respond("Operation not confirmed.")
            return

        guild: PycordGuild = await self.bot.find_guild(ctx.guild.id)
        pycord_event: PycordEvent = await self.bot.find_event(event_id=event)

        if pycord_event is None:
            # TODO Make a nice message
            await ctx.respond("Event was not found.")
            return

        if not guild.is_configured():
            # TODO Make a nice message
            await ctx.respond("Guild is not configured.")
            return

        start_date: datetime = pycord_event.starts.replace(tzinfo=ZoneInfo("UTC"))
        end_date: datetime = pycord_event.ends.replace(tzinfo=ZoneInfo("UTC"))

        # TODO Make ongoing events cancellable
        if (
            pycord_event.ended is not None
            or end_date <= datetime.now(tz=ZoneInfo("UTC"))
            or start_date <= datetime.now(tz=ZoneInfo("UTC"))
        ):
            # TODO Make a nice message
            await ctx.respond("Finished or ongoing events cannot be cancelled.")
            return

        await pycord_event.cancel()

        # TODO Make a nice message
        await ctx.respond("Event was cancelled.")

    # TODO Introduce i18n
    @command_group.command(
        name="show",
        description="Show the details about certain event",
    )
    @option(
        "event",
        description="Name of the event",
        autocomplete=basic_autocomplete(autocomplete_active_events),
        required=True,
    )
    async def command_event_show(self, ctx: ApplicationContext, event: str) -> None:
        guild: PycordGuild = await self.bot.find_guild(ctx.guild.id)
        pycord_event: PycordEvent = await self.bot.find_event(event_id=event)

        if pycord_event is None:
            # TODO Make a nice message
            await ctx.respond("Event was not found.")
            return

        starts_date: datetime = pycord_event.starts.replace(tzinfo=ZoneInfo("UTC"))
        ends_date: datetime = pycord_event.ends.replace(tzinfo=ZoneInfo("UTC"))

        # TODO Make a nice message
        await ctx.respond(
            f"**Event details**\n\nName: {pycord_event.name}\nStarts: <t:{int(starts_date.timestamp())}>\nEnds: <t:{int(ends_date.timestamp())}>"
        )


def setup(bot: PycordBot) -> None:
    bot.add_cog(Event(bot))