import logging
import asyncio
from typing import Union
from datetime import timedelta

import discord
from discord.ext import commands

from redbot.core import Config, checks, RedContext
from redbot.core.utils.chat_formatting import pagify, box
from redbot.core.utils.antispam import AntiSpam
from redbot.core.bot import Red
from redbot.core.i18n import CogI18n
from redbot.core.utils.tunnel import Tunnel


_ = CogI18n("Reports", __file__)

log = logging.getLogger("red.reports")


class Reports:

    default_guild_settings = {
        "output_channel": None,
        "active": False,
        "next_ticket": 1
    }

    default_report = {
        'report': {}
    }

    # This can be made configureable later if it
    # becomes an issue.
    # Intervals should be a list of tuples in the form
    # (period: timedelta, max_frequency: int)
    # see redbot/core/utils/antispam.py for more details

    intervals = [
        (timedelta(seconds=5), 1),
        (timedelta(minutes=5), 3),
        (timedelta(hours=1), 10),
        (timedelta(days=1), 24)
    ]

    def __init__(self, bot: Red):
        self.bot = bot
        self.config = Config.get_conf(
            self, 78631113035100160, force_registration=True)
        self.config.register_guild(**self.default_guild_settings)
        self.config.register_custom('REPORT', **self.default_report)
        self.antispam = {}
        self.user_cache = []
        self.tunnel_store = {}
        # (guild, ticket#):
        #   {'tun': Tunnel, 'msgs': List[int]}

    @property
    def tunnels(self):
        return [
            x['tun'] for x in self.tunnel_store.values()
        ]

    def __unload(self):
        for tun in self.tunnels:
            tun.close()

    @checks.admin_or_permissions(manage_guild=True)
    @commands.guild_only()
    @commands.group(name="reportset")
    async def reportset(self, ctx: RedContext):
        """
        settings for reports
        """
        pass

    @checks.admin_or_permissions(manage_guild=True)
    @reportset.command(name="output")
    async def setoutput(self, ctx: RedContext, channel: discord.TextChannel):
        """sets the output channel"""
        await self.config.guild(ctx.guild).output_channel.set(channel.id)
        await ctx.send(_("Report Channel Set."))

    @checks.admin_or_permissions(manage_guild=True)
    @reportset.command(name="toggleactive")
    async def report_toggle(self, ctx: RedContext):
        """Toggles whether the Reporting tool is enabled or not"""

        active = await self.config.guild(ctx.guild).active()
        active = not active
        await self.config.guild(ctx.guild).active.set(active)
        if active:
            await ctx.send(_("Reporting now enabled"))
        else:
            await ctx.send(_("Reporting disabled."))

    async def internal_filter(self, m: discord.Member, mod=False, perms=None):
        ret = False
        if mod:
            guild = m.guild
            admin_role = discord.utils.get(
                guild.roles, id=await self.bot.db.guild(guild).admin_role()
            )
            mod_role = discord.utils.get(
                guild.roles, id=await self.bot.db.guild(guild).mod_role()
            )
            ret |= any(r in m.roles for r in (mod_role, admin_role))
        if perms:
            ret |= m.guild_permissions >= perms
        # The following line is for consistency with how perms are handled
        # in Red, though I'm not sure it makse sense to use here.
        ret |= await self.bot.is_owner(m)
        return ret

    async def discover_guild(self, author: discord.User, *,
                             mod: bool=False,
                             permissions: Union[discord.Permissions, dict]={},
                             prompt: str=""):
        """
        discovers which of shared guilds between the bot
        and provided user based on conditions (mod or permissions is an or)

        prompt is for providing a user prompt for selection
        """
        shared_guilds = []
        if isinstance(permissions, discord.Permissions):
            perms = permissions
        else:
            permissions = discord.Permissions(**perms)

        for guild in self.bot.guilds:
            x = guild.get_member(author.id)
            if x is not None:
                if await self.internal_filter(x, mod, perms):
                    shared_guilds.append(guild)
        if len(shared_guilds) == 0:
            raise ValueError("No Qualifying Shared Guilds")
            return
        if len(shared_guilds) == 1:
            return shared_guilds[0]
        output = ""
        guilds = sorted(shared_guilds, key=lambda g: g.name)
        for i, guild in enumerate(guilds, 1):
            output += "{}: {}\n".format(i, guild.name)
        output += "\n{}".format(prompt)

        for page in pagify(output, delims=["\n"]):
            dm = await author.send(box(page))

        def pred(m):
            return m.author == author and m.channel == dm.channel

        try:
            message = await self.bot.wait_for(
                'message', check=pred, timeout=45
            )
        except asyncio.TimeoutError:
            await author.send(
                _("You took too long to select. Try again later.")
            )
            return None

        try:
            message = int(message.content.strip())
            guild = guilds[message - 1]
        except (ValueError, IndexError):
            await author.send(_("That wasn't a valid choice."))
            return None
        else:
            return guild

    async def send_report(self, msg: discord.Message, guild: discord.Guild):

        author = guild.get_member(msg.author.id)
        report = msg.clean_content
        avatar = author.avatar_url

        em = discord.Embed(description=report)
        em.set_author(
            name=_('Report from {0.display_name}').format(author),
            icon_url=avatar
        )

        ticket_number = await self.config.guild(guild).next_ticket()
        await self.config.guild(guild).next_ticket.set(ticket_number + 1)
        em.set_footer(text=_("Report #{}").format(ticket_number))

        channel_id = await self.config.guild(guild).output_channel()
        channel = guild.get_channel(channel_id)
        if channel is not None:
            try:
                await channel.send(embed=em)
            except (discord.Forbidden, discord.HTTPException):
                return None
        else:
            return None

        await self.config.custom('REPORT', guild.id, ticket_number).report.set(
            {'user_id': author.id, 'report': report}
        )
        return ticket_number

    @commands.group(name="report", invoke_without_command=True)
    async def report(self, ctx: RedContext):
        "Follow the prompts to make a report"
        author = ctx.author
        guild = ctx.guild
        if guild is None:
            guild = await self.discover_guild(
                author,
                prompt=_("Select a server to make a report in by number.")
            )
        else:
            try:
                await ctx.message.delete()
            except discord.Forbidden:
                pass
        if guild is None:
            return
        g_active = await self.config.guild(guild).active()
        if not g_active:
            return await author.send(
                _("Reporting has not been enabled for this server")
            )
        if guild.id not in self.antispam:
            self.antispam[guild.id] = {}
        if author.id not in self.antispam[guild.id]:
            self.antispam[guild.id][author.id] = AntiSpam(self.intervals)
        if self.antispam[guild.id][author.id].spammy:
            return await author.send(
                _("You've sent a few too many of these recently. "
                  "Contact a server admin to resolve this, or try again "
                  "later.")
            )

        if author.id in self.user_cache:
            return await author.send(
                _("Finish making your prior report "
                  "before making an additional one")
            )

        if ctx.guild:
            try:
                await ctx.message.delete()
            except (discord.Forbidden, discord.HTTPException):
                pass
        self.user_cache.append(author.id)

        try:
            dm = await author.send(
                _("Please respond to this message with your Report."
                  "\nYour report should be a single message")
            )
        except discord.Forbidden:
            await ctx.send(
                _("This requires DMs enabled.")
            )
            self.user_cache.remove(author.id)
            return

        def pred(m):
            return m.author == author and m.channel == dm.channel

        try:
            message = await self.bot.wait_for(
                'message', check=pred, timeout=180
            )
        except asyncio.TimeoutError:
            await author.send(
                _("You took too long. Try again later.")
            )
        else:
            val = await self.send_report(message, guild)
            if val is None:
                await author.send(
                    _("There was an error sending your report.")
                )
            else:
                await author.send(
                    _("Your report was submitted. (Ticket #{})").format(val)
                )
            self.antispam[guild.id][author.id].stamp()

        self.user_cache.remove(author.id)

    async def on_raw_reaction_add(self, payload):
        """
        oh dear....
        """
        if not str(payload.emoji) == "\N{NEGATIVE SQUARED CROSS MARK}":
            return

        _id = payload.message_id
        t = next(filter(
            lambda x: _id in x[1]['msgs'],
            self.tunnel_store.items()
        ), None)

        if t is None:
            return
        tun = t[1]['tun']
        if payload.user_id in [x.id for x in tun.members]:
            await tun.react_close(
                uid=payload.user_id,
                message=_("{closer} has closed the correspondence")
            )
            self.tunnel_store.pop(t[0], None)

    async def on_message(self, message: discord.Message):
        for k, v in self.tunnel_store.items():
            topic = _("Re: ticket# {1} in {0.name}").format(*k)
            # Tunnels won't forward unintended messages, this is safe
            msgs = await v['tun'].communicate(message=message, topic=topic)
            if msgs:
                self.tunnel_store[k]['msgs'] = msgs

    @checks.mod_or_permissions(manage_members=True)
    @report.command(name='interact')
    async def response(self, ctx, ticket_number: int):
        """
        opens a message tunnel between things you say in this channel
        and the ticket opener's direct messages

        tunnels do not persist across bot restarts
        """

        # note, mod_or_permissions is an implicit guild_only
        guild = ctx.guild
        rec = await self.config.custom(
            'REPORT', guild.id, ticket_number).report()

        try:
            user = guild.get_member(rec.get('user_id'))
        except KeyError:
            return await ctx.send(
                _("That ticket doesn't seem to exist")
            )

        if user is None:
            return await ctx.send(
                _("That user isn't here anymore.")
            )

        tun = Tunnel(recipient=user, origin=ctx.channel, sender=ctx.author)

        if tun is None:
            return await ctx.send(
                _("Either you or the user you are trying to reach already "
                  "has an open communication.")
            )

        big_topic = _(
            "{who} opened a 2-way communication."
            "about ticket number {ticketnum}. Anything you say or upload here "
            "(8MB file size limitation on uploads) "
            "will be forwarded to them until the communication is closed.\n"
            "You can close a communication at any point "
            "by reacting with the X to the last message recieved. "
            "\nAny message succesfully forwarded with be marked with a check."
            "\nTunnels are not persistent across bot restarts."
        )
        topic = big_topic.format(
            ticketnum=ticket_number,
            who=_("A moderator in `{guild.name}` has").format(guild=guild)
        )
        try:
            m = await tun.communicate(
                message=ctx.message, topic=topic, skip_message_content=True
            )
        except discord.Forbidden:
            await ctx.send(_("User has disabled DMs."))
            tun.close()
        else:
            self.tunnel_store[(guild, ticket_number)] = {'tun': tun, 'msgs': m}
            await ctx.send(
                big_topic.format(who=_("You have"), ticketnum=ticket_number)
            )