import discord
from discord.ext import commands
from redbot.core import Config, checks, RedContext
from redbot.core.utils.chat_formatting import pagify
from redbot.core.bot import Red
from redbot.core.i18n import CogI18n
from .streamtypes import TwitchStream, HitboxStream, MixerStream, PicartoStream, TwitchCommunity, YoutubeStream
from .errors import (OfflineStream, StreamNotFound, APIError, InvalidYoutubeCredentials,
                     CommunityNotFound, OfflineCommunity, StreamsError, InvalidTwitchCredentials)
from . import streamtypes as StreamClasses
from collections import defaultdict
import asyncio
import re

CHECK_DELAY = 60


_ = CogI18n("Streams", __file__)


class Streams:

    global_defaults = {
        "tokens": {},
        "streams": [],
        "communities": []
    }

    guild_defaults = {
        "autodelete": False,
        "mention_everyone": False,
        "mention_here": False
    }

    role_defaults = {
        "mention": False
    }

    def __init__(self, bot: Red):
        self.db = Config.get_conf(self, 26262626)

        self.db.register_global(**self.global_defaults)

        self.db.register_guild(**self.guild_defaults)

        self.db.register_role(**self.role_defaults)

        self.bot = bot

        self.bot.loop.create_task(self._initialize_lists())

        self.yt_cid_pattern = re.compile("^UC[-_A-Za-z0-9]{21}[AQgw]$")

    def check_name_or_id(self, data: str):
        matched = self.yt_cid_pattern.fullmatch(data)
        if matched is None:
            return True
        return False

    async def _initialize_lists(self):
        self.streams = await self.load_streams()
        self.communities = await self.load_communities()

        self.task = self.bot.loop.create_task(self._stream_alerts())

    @commands.command()
    async def twitch(self, ctx, channel_name: str):
        """Checks if a Twitch channel is streaming"""
        token = await self.db.tokens.get_raw(TwitchStream.__name__, default=None)
        stream = TwitchStream(name=channel_name,
                              token=token)
        await self.check_online(ctx, stream)

    @commands.command()
    async def youtube(self, ctx, channel_id_or_name: str):
        """
        Checks if a Youtube channel is streaming
        """
        apikey = await self.db.tokens.get_raw(YoutubeStream.__name__, default=None)
        is_name = self.check_name_or_id(channel_id_or_name)
        if is_name:
            stream = YoutubeStream(name=channel_id_or_name, token=apikey)
        else:
            stream = YoutubeStream(id=channel_id_or_name, token=apikey)
        await self.check_online(ctx, stream)

    @commands.command()
    async def hitbox(self, ctx, channel_name: str):
        """Checks if a Hitbox channel is streaming"""
        stream = HitboxStream(name=channel_name)
        await self.check_online(ctx, stream)

    @commands.command()
    async def mixer(self, ctx, channel_name: str):
        """Checks if a Mixer channel is streaming"""
        stream = MixerStream(name=channel_name)
        await self.check_online(ctx, stream)

    @commands.command()
    async def picarto(self, ctx, channel_name: str):
        """Checks if a Picarto channel is streaming"""
        stream = PicartoStream(name=channel_name)
        await self.check_online(ctx, stream)

    async def check_online(self, ctx, stream):
        try:
            embed = await stream.is_online()
        except OfflineStream:
            await ctx.send(_("The stream is offline."))
        except StreamNotFound:
            await ctx.send(_("The channel doesn't seem to exist."))
        except InvalidTwitchCredentials:
            await ctx.send(_("The twitch token is either invalid or has not been set. "
                             "See `{}`.").format("{}streamset twitchtoken".format(ctx.prefix)))
        except InvalidYoutubeCredentials:
            await ctx.send(_("The Youtube API key is either invalid or has not been set. "
                             "See {}.").format("`{}streamset youtubekey`".format(ctx.prefix)))
        except APIError:
            await ctx.send(_("Something went wrong whilst trying to contact the "
                           "stream service's API."))
        else:
            await ctx.send(embed=embed)

    @commands.group()
    @commands.guild_only()
    @checks.mod()
    async def streamalert(self, ctx):
        if ctx.invoked_subcommand is None:
            await ctx.send_help()

    @streamalert.group(name="twitch")
    async def _twitch(self, ctx):
        """Twitch stream alerts"""
        if ctx.invoked_subcommand is None or ctx.invoked_subcommand == self._twitch:
            await ctx.send_help()

    @_twitch.command(name="channel")
    async def twitch_alert_channel(self, ctx: RedContext, channel_name: str):
        """Sets a Twitch stream alert notification in the channel"""
        await self.stream_alert(ctx, TwitchStream, channel_name.lower())

    @_twitch.command(name="community")
    async def twitch_alert_community(self, ctx: RedContext, community: str):
        """Sets a Twitch stream alert notification in the channel
        for the specified community."""
        await self.community_alert(ctx, TwitchCommunity, community.lower())

    @streamalert.command(name="youtube")
    async def youtube_alert(self, ctx: RedContext, channel_name_or_id: str):
        """Sets a Youtube stream alert notification in the channel"""
        await self.stream_alert(ctx, YoutubeStream, channel_name_or_id)

    @streamalert.command(name="hitbox")
    async def hitbox_alert(self, ctx, channel_name: str):
        """Sets a Hitbox stream alert notification in the channel"""
        await self.stream_alert(ctx, HitboxStream, channel_name)

    @streamalert.command(name="mixer")
    async def mixer_alert(self, ctx, channel_name: str):
        """Sets a Mixer stream alert notification in the channel"""
        await self.stream_alert(ctx, MixerStream, channel_name)

    @streamalert.command(name="picarto")
    async def picarto_alert(self, ctx, channel_name: str):
        """Sets a Picarto stream alert notification in the channel"""
        await self.stream_alert(ctx, PicartoStream, channel_name)

    @streamalert.command(name="stop")
    async def streamalert_stop(self, ctx, _all: bool=False):
        """Stops all stream notifications in the channel

        Adding 'yes' will disable all notifications in the server"""
        streams = self.streams.copy()
        local_channel_ids = [c.id for c in ctx.guild.channels]
        to_remove = []

        for stream in streams:
            for channel_id in stream.channels:
                if channel_id == ctx.channel.id:
                    stream.channels.remove(channel_id)
                elif _all and ctx.channel.id in local_channel_ids:
                    if channel_id in stream.channels:
                        stream.channels.remove(channel_id)

            if not stream.channels:
                to_remove.append(stream)

        for stream in to_remove:
            streams.remove(stream)

        self.streams = streams
        await self.save_streams()

        msg = _("All {}'s stream alerts have been disabled."
                "").format("server" if _all else "channel")

        await ctx.send(msg)

    @streamalert.command(name="list")
    async def streamalert_list(self, ctx):
        streams_list = defaultdict(list)
        guild_channels_ids = [c.id for c in ctx.guild.channels]
        msg = _("Active stream alerts:\n\n")

        for stream in self.streams:
            for channel_id in stream.channels:
                if channel_id in guild_channels_ids:
                    streams_list[channel_id].append(stream.name.lower())

        if not streams_list:
            await ctx.send(_("There are no active stream alerts in this server."))
            return

        for channel_id, streams in streams_list.items():
            channel = ctx.guild.get_channel(channel_id)
            msg += "** - #{}**\n{}\n".format(channel, ", ".join(streams))

        for page in pagify(msg):
            await ctx.send(page)

    async def stream_alert(self, ctx, _class, channel_name):
        stream = self.get_stream(_class, channel_name)
        if not stream:
            token = await self.db.tokens.get_raw(_class.__name__, default=None)
            is_yt = _class.__name__ == "YoutubeStream"
            if is_yt and not self.check_name_or_id(channel_name):
                stream = _class(id=channel_name, token=token)
            else:
                stream = _class(name=channel_name,
                                token=token)
            try:
                exists = await self.check_exists(stream)
            except InvalidTwitchCredentials:
                await ctx.send(
                    _("The twitch token is either invalid or has not been set. "
                      "See {}.").format("`{}streamset twitchtoken`".format(ctx.prefix)))
                return
            except InvalidYoutubeCredentials:
                await ctx.send(_("The Youtube API key is either invalid or has not been set. "
                                 "See {}.").format("`{}streamset youtubekey`".format(ctx.prefix)))
                return
            except APIError:
                await ctx.send(
                    _("Something went wrong whilst trying to contact the "
                      "stream service's API."))
                return
            else:
                if not exists:
                    await ctx.send(_("That channel doesn't seem to exist."))
                    return

        await self.add_or_remove(ctx, stream)

    async def community_alert(self, ctx, _class, community_name):
        community = self.get_community(_class, community_name)
        if not community:
            token = await self.db.tokens.get_raw(_class.__name__, default=None)
            community = _class(name=community_name, token=token)
            try:
                await community.get_community_streams()
            except InvalidTwitchCredentials:
                await ctx.send(
                    _("The twitch token is either invalid or has not been set. "
                      "See {}.").format("`{}streamset twitchtoken`".format(ctx.prefix)))
                return
            except CommunityNotFound:
                await ctx.send(_("That community doesn't seem to exist."))
                return
            except APIError:
                await ctx.send(
                    _("Something went wrong whilst trying to contact the "
                      "stream service's API."))
                return
            except OfflineCommunity:
                pass

        await self.add_or_remove_community(ctx, community)

    @commands.group()
    @checks.mod()
    async def streamset(self, ctx):
        if ctx.invoked_subcommand is None:
            await ctx.send_help()

    @streamset.command()
    @checks.is_owner()
    async def twitchtoken(self, ctx, token: str):
        """Set the Client ID for twitch.

        To do this, follow these steps:
          1. Go to this page: https://dev.twitch.tv/dashboard/apps.
          2. Click *Register Your Application*
          3. Enter a name, set the OAuth Redirect URI to `http://localhost`, and
             select an Application Category of your choosing.
          4. Click *Register*, and on the following page, copy the Client ID.
          5. Paste the Client ID into this command. Done!

        """
        await self.db.tokens.set_raw("TwitchStream", value=token)
        await self.db.tokens.set_raw("TwitchCommunity", value=token)
        await ctx.send(_("Twitch token set."))

    @streamset.command()
    @checks.is_owner()
    async def youtubekey(self, ctx: RedContext, key: str):
        """Sets the API key for Youtube.

        To get one, do the following:

        1. Create a project (see https://support.google.com/googleapi/answer/6251787 for details)
        2. Enable the Youtube Data API v3 (see https://support.google.com/googleapi/answer/6158841 for instructions)
        3. Set up your API key (see https://support.google.com/googleapi/answer/6158862 for instructions)
        4. Copy your API key and paste it into this command. Done!

        """
        await self.db.tokens.set_raw("YoutubeStream", value=key)
        await ctx.send(_("Youtube key set."))

    @streamset.group()
    @commands.guild_only()
    async def mention(self, ctx):
        """Sets mentions for stream alerts."""
        if ctx.invoked_subcommand is None or ctx.invoked_subcommand == self.mention:
            await ctx.send_help()

    @mention.command(aliases=["everyone"])
    @commands.guild_only()
    async def all(self, ctx):
        """Toggles everyone mention"""
        guild = ctx.guild
        current_setting = await self.db.guild(guild).mention_everyone()
        if current_setting:
            await self.db.guild(guild).mention_everyone.set(False)
            await ctx.send(_("{} will no longer be mentioned "
                           "for a stream alert.").format("@\u200beveryone"))
        else:
            await self.db.guild(guild).mention_everyone.set(True)
            await ctx.send(_("When a stream configured for stream alerts "
                           "comes online, {} will be mentioned").format("@\u200beveryone"))

    @mention.command(aliases=["here"])
    @commands.guild_only()
    async def online(self, ctx):
        """Toggles here mention"""
        guild = ctx.guild
        current_setting = await self.db.guild(guild).mention_here()
        if current_setting:
            await self.db.guild(guild).mention_here.set(False)
            await ctx.send(_("{} will no longer be mentioned "
                           "for a stream alert.").format("@\u200bhere"))
        else:
            await self.db.guild(guild).mention_here.set(True)
            await ctx.send(_("When a stream configured for stream alerts "
                           "comes online, {} will be mentioned").format("@\u200bhere"))

    @mention.command()
    @commands.guild_only()
    async def role(self, ctx, *, role: discord.Role):
        """Toggles role mention"""
        current_setting = await self.db.role(role).mention()
        if not role.mentionable:
            await ctx.send("That role is not mentionable!")
            return
        if current_setting:
            await self.db.role(role).mention.set(False)
            await ctx.send(_("{} will no longer be mentioned "
                           "for a stream alert").format("@\u200b{}".format(role.name)))
        else:
            await self.db.role(role).mention.set(True)
            await ctx.send(_("When a stream configured for stream alerts "
                             "comes online, {} will be mentioned"
                             "").format("@\u200b{}".format(role.name)))

    @streamset.command()
    @commands.guild_only()
    async def autodelete(self, ctx, on_off: bool):
        """Toggles automatic deletion of notifications for streams that go offline"""
        await self.db.guild(ctx.guild).autodelete.set(on_off)
        if on_off:
            await ctx.send("The notifications will be deleted once "
                           "streams go offline.")
        else:
            await ctx.send("Notifications will never be deleted.")

    async def add_or_remove(self, ctx, stream):
        if ctx.channel.id not in stream.channels:
            stream.channels.append(ctx.channel.id)
            if stream not in self.streams:
                self.streams.append(stream)
            await ctx.send(_("I'll send a notification in this channel when {} "
                           "is online.").format(stream.name))
        else:
            stream.channels.remove(ctx.channel.id)
            if not stream.channels:
                self.streams.remove(stream)
            await ctx.send(_("I won't send notifications about {} in this "
                           "channel anymore.").format(stream.name))

        await self.save_streams()

    async def add_or_remove_community(self, ctx, community):
        if ctx.channel.id not in community.channels:
            community.channels.append(ctx.channel.id)
            if community not in self.communities:
                self.communities.append(community)
            await ctx.send(_("I'll send a notification in this channel when a "
                             "channel is streaming to the {} community"
                             "").format(community.name))
        else:
            community.channels.remove(ctx.channel.id)
            if not community.channels:
                self.communities.remove(community)
            await ctx.send(_("I won't send notifications about channels streaming "
                             "to the {} community in this channel anymore"
                             "").format(community.name))
        await self.save_communities()

    def get_stream(self, _class, name):
        for stream in self.streams:
            # if isinstance(stream, _class) and stream.name == name:
            #    return stream
            # Reloading this cog causes an issue with this check ^
            # isinstance will always return False
            # As a workaround, we'll compare the class' name instead.
            # Good enough.
            if _class.__name__ == "YoutubeStream" and stream.type == _class.__name__:
                # Because name could be a username or a channel id
                if self.check_name_or_id(name) and stream.name.lower() == name.lower():
                    return stream
                elif not self.check_name_or_id(name) and stream.id == name:
                    return stream
            if stream.type == _class.__name__ and stream.name.lower() == name.lower():
                return stream

    def get_community(self, _class, name):
        for community in self.communities:
            if community.type == _class.__name__ and community.name.lower() == name.lower():
                return community

    async def check_exists(self, stream):
        try:
            await stream.is_online()
        except OfflineStream:
            pass
        except StreamNotFound:
            return False
        except StreamsError:
            raise
        return True

    async def _stream_alerts(self):
        while True:
            try:
                await self.check_streams()
            except asyncio.CancelledError:
                pass
            try:
                await self.check_communities()
            except asyncio.CancelledError:
                pass
            await asyncio.sleep(CHECK_DELAY)

    async def check_streams(self):
        for stream in self.streams:
            try:
                embed = await stream.is_online()
            except OfflineStream:
                for message in stream._messages_cache:
                    try:
                        autodelete = self.db.guild(message.guild).autodelete()
                        if autodelete:
                            await message.delete()
                    except:
                        pass
                stream._messages_cache.clear()
            except:
                pass
            else:
                if stream._messages_cache:
                    continue
                for channel_id in stream.channels:
                    channel = self.bot.get_channel(channel_id)
                    mention_str = await self._get_mention_str(channel.guild)

                    if mention_str:
                        content = "{}, {} is online!".format(mention_str, stream.name)
                    else:
                        content = "{} is online!".format(stream.name)

                    try:
                        m = await channel.send(content, embed=embed)
                        stream._messages_cache.append(m)
                    except:
                        pass

    async def _get_mention_str(self, guild: discord.Guild):
        settings = self.db.guild(guild)
        mentions = []
        if await settings.mention_everyone():
            mentions.append('@everyone')
        if await settings.mention_here():
            mentions.append('@here')
        for role in guild.roles:
            if await self.db.role(role).mention():
                mentions.append(role.mention)
        return ' '.join(mentions)

    async def check_communities(self):
        for community in self.communities:
            try:
                streams = community.get_community_streams()
            except CommunityNotFound:
                print(_("Community {} not found!").format(community.name))
                continue
            except OfflineCommunity:
                pass
            else:
                token = self.db.tokens().get(TwitchStream.__name__)
                for channel in community.channels:
                    chn = self.bot.get_channel(channel)
                    await chn.send(_("Online streams for {}").format(community.name))
                for stream in streams:
                    stream_obj = TwitchStream(
                        token=token, name=stream["channel"]["name"],
                        id=stream["_id"]
                    )
                    try:
                        emb = await stream_obj.is_online()
                    except:
                        pass
                    else:
                        for channel in community.channels:
                            chn = self.bot.get_channel(channel)
                            await chn.send(embed=emb)

    async def load_streams(self):
        streams = []

        for raw_stream in await self.db.streams():
            _class = getattr(StreamClasses, raw_stream["type"], None)
            if not _class:
                continue

            token = await self.db.tokens.get_raw(_class.__name__)
            streams.append(_class(token=token, **raw_stream))

        # issue 1191 extended resolution: Remove this after suitable period
        # Fast dedupe below
        seen = set()
        seen_add = seen.add
        return [x for x in streams
                if not (x.name.lower() in seen or seen_add(x.name.lower()))]

        # return streams

    async def load_communities(self):
        communities = []

        for raw_community in await self.db.communities():
            _class = getattr(StreamClasses, raw_community["type"], None)
            if not _class:
                continue

            token = await self.db.tokens.get_raw(_class.__name__, default=None)
            communities.append(_class(token=token, **raw_community))

        # issue 1191 extended resolution: Remove this after suitable period
        # Fast dedupe below
        seen = set()
        seen_add = seen.add
        return [x for x in communities
                if not (x.name.lower() in seen or seen_add(x.name.lower()))]
        # return communities

    async def save_streams(self):
        raw_streams = []
        for stream in self.streams:
            raw_streams.append(stream.export())

        await self.db.streams.set(raw_streams)

    async def save_communities(self):
        raw_communities = []
        for community in self.communities:
            raw_communities.append(community.export())

        await self.db.communities.set(raw_communities)

    def __unload(self):
        self.task.cancel()