"""Obviously, dispatches stuff"""

#    Friendly Telegram (telegram userbot)
#    Copyright (C) 2018-2022 The Authors

#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU Affero General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.

#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU Affero General Public License for more details.

#    You should have received a copy of the GNU Affero General Public License
#    along with this program.  If not, see <https://www.gnu.org/licenses/>.

# █ █ ▀ █▄▀ ▄▀█ █▀█ ▀    ▄▀█ ▀█▀ ▄▀█ █▀▄▀█ ▄▀█
# █▀█ █ █ █ █▀█ █▀▄ █ ▄  █▀█  █  █▀█ █ ▀ █ █▀█
#
#              © Copyright 2022
#
#          https://t.me/hikariatama
#
# 🔒 Licensed under the GNU GPLv3
# 🌐 https://www.gnu.org/licenses/agpl-3.0.html

import asyncio
import collections
import copy
import functools
import logging
import re
import traceback
from types import FunctionType
from typing import Tuple, Union

from telethon import types
from telethon.tl.types import Message

from . import main, security, utils
from .database import Database
from .loader import Modules

# Keys for layout switch
ru_keys = 'ёйцукенгшщзхъфывапролджэячсмитьбю.Ё"№;%:?ЙЦУКЕНГШЩЗХЪФЫВАПРОЛДЖЭ/ЯЧСМИТЬБЮ,'
en_keys = "`qwertyuiop[]asdfghjkl;'zxcvbnm,./~@#$%^&QWERTYUIOP{}ASDFGHJKL:\"|ZXCVBNM<>?"


def _decrement_ratelimit(delay, data, key, severity):
    def inner():
        data[key] = max(0, data[key] - severity)

    asyncio.get_event_loop().call_later(delay, inner)


class CommandDispatcher:
    def __init__(self, modules: Modules, db: Database, no_nickname: bool = False):
        self._modules = modules
        self._db = db
        self.security = security.SecurityManager(db)
        self.no_nickname = no_nickname
        self._ratelimit_storage_user = collections.defaultdict(int)
        self._ratelimit_storage_chat = collections.defaultdict(int)
        self._ratelimit_max_user = db.get(__name__, "ratelimit_max_user", 30)
        self._ratelimit_max_chat = db.get(__name__, "ratelimit_max_chat", 100)
        self.check_security = self.security.check

    async def init(self, client: "TelegramClient"):  # type: ignore
        await self.security.init(client)
        me = await client.get_me()

        self.client = client  # Intended to be used to track user in logging

        self._me = me.id
        self._cached_username = me.username.lower() if me.username else str(me.id)

    async def _handle_ratelimit(self, message: Message, func: callable) -> bool:
        if await self.security.check(
            message,
            security.OWNER | security.SUDO | security.SUPPORT,
        ):
            return True

        func = getattr(func, "__func__", func)
        ret = True
        chat = self._ratelimit_storage_chat[message.chat_id]

        if message.sender_id:
            user = self._ratelimit_storage_user[message.sender_id]
            severity = (5 if getattr(func, "ratelimit", False) else 2) * (
                (user + chat) // 30 + 1
            )
            user += severity
            self._ratelimit_storage_user[message.sender_id] = user
            if user > self._ratelimit_max_user:
                ret = False
            else:
                self._ratelimit_storage_chat[message.chat_id] = chat

            _decrement_ratelimit(
                self._ratelimit_max_user * severity,
                self._ratelimit_storage_user,
                message.sender_id,
                severity,
            )
        else:
            severity = (5 if getattr(func, "ratelimit", False) else 2) * (
                chat // 15 + 1
            )

        chat += severity

        if chat > self._ratelimit_max_chat:
            ret = False

        _decrement_ratelimit(
            self._ratelimit_max_chat * severity,
            self._ratelimit_storage_chat,
            message.chat_id,
            severity,
        )

        return ret

    def _handle_grep(self, message: Message) -> Message:
        # Allow escaping grep with double stick
        if "||grep" in message.text or "|| grep" in message.text:
            message.raw_text = re.sub(r"\|\| ?grep", "| grep", message.raw_text)
            message.text = re.sub(r"\|\| ?grep", "| grep", message.text)
            message.message = re.sub(r"\|\| ?grep", "| grep", message.message)
            return message

        grep = False
        if not re.search(r".+\| ?grep (.+)", message.raw_text):
            return message

        grep = re.search(r".+\| ?grep (.+)", message.raw_text).group(1)
        message.text = re.sub(r"\| ?grep.+", "", message.text)
        message.raw_text = re.sub(r"\| ?grep.+", "", message.raw_text)
        message.message = re.sub(r"\| ?grep.+", "", message.message)

        ungrep = False

        if re.search(r"-v (.+)", grep):
            ungrep = re.search(r"-v (.+)", grep).group(1)
            grep = re.sub(r"(.+) -v .+", r"\g<1>", grep)

        grep = utils.escape_html(grep).strip() if grep else False
        ungrep = utils.escape_html(ungrep).strip() if ungrep else False

        old_edit = message.edit
        old_reply = message.reply
        old_respond = message.respond

        def process_text(text: str) -> str:
            nonlocal grep, ungrep
            res = []

            for line in text.split("\n"):
                if (
                    grep
                    and grep in utils.remove_html(line)
                    and (not ungrep or ungrep not in utils.remove_html(line))
                ):
                    res.append(
                        utils.remove_html(line, escape=True).replace(
                            grep, f"<u>{grep}</u>"
                        )
                    )

                if not grep and ungrep and ungrep not in utils.remove_html(line):
                    res.append(utils.remove_html(line, escape=True))

            cont = (
                (f"contain <b>{grep}</b>" if grep else "")
                + (" and" if grep and ungrep else "")
                + ((" do not contain <b>" + ungrep + "</b>") if ungrep else "")
            )

            if res:
                text = f"<i>💬 Lines that {cont}:</i>\n" + ("\n".join(res))
            else:
                text = f"💬 <i>No lines that {cont}</i>"

            return text

        async def my_edit(text, *args, **kwargs):
            text = process_text(text)
            kwargs["parse_mode"] = "HTML"
            return await old_edit(text, *args, **kwargs)

        async def my_reply(text, *args, **kwargs):
            text = process_text(text)
            kwargs["parse_mode"] = "HTML"
            return await old_reply(text, *args, **kwargs)

        async def my_respond(text, *args, **kwargs):
            text = process_text(text)
            kwargs["parse_mode"] = "HTML"
            return await old_respond(text, *args, **kwargs)

        message.edit = my_edit
        message.reply = my_reply
        message.respond = my_respond

        return message

    async def _handle_command(
        self,
        event,
    ) -> Union[bool, Tuple[Message, str, str, FunctionType]]:
        if not hasattr(event, "message") or not hasattr(event.message, "message"):
            return False

        if (
            len(prefix := self._db.get(main.__name__, "command_prefix", False) or ".")
            != 1
        ):
            prefix = "."
            self._db.set(main.__name__, "command_prefix", prefix)
            logging.warning("Prefix has been reset to a default one («.»)")

        change = str.maketrans(ru_keys + en_keys, en_keys + ru_keys)
        message = utils.censor(event.message)

        if not event.message.message:
            return False

        if (
            event.message.message.startswith(str.translate(prefix, change))
            and str.translate(prefix, change) != prefix
        ):
            prefix = str.translate(prefix, change)
            message.message = str.translate(message.message, change)
        elif not event.message.message.startswith(prefix):
            return False

        if (
            event.sticker
            or event.dice
            or event.audio
            or event.via_bot_id
            or getattr(event, "reactions", False)
        ):
            return False

        blacklist_chats = self._db.get(main.__name__, "blacklist_chats", [])
        whitelist_chats = self._db.get(main.__name__, "whitelist_chats", [])
        whitelist_modules = self._db.get(main.__name__, "whitelist_modules", [])

        if utils.get_chat_id(message) in blacklist_chats or (
            whitelist_chats and utils.get_chat_id(message) not in whitelist_chats
        ):
            return False

        if (
            message.out
            and len(message.message) > 2
            and message.message.startswith(prefix * 2)
        ):
            # Allow escaping commands using .'s
            await message.edit(
                message.message[1:],
                parse_mode=lambda s: (
                    s,
                    utils.relocate_entities(message.entities, -1, message.message)
                    or (),
                ),
            )
            return False

        message.message = message.message[1:]

        if not message.message:
            return False  # Message is just the prefix

        utils.relocate_entities(message.entities, -1)

        initiator = getattr(event, "sender_id", 0)

        command = message.message.split(maxsplit=1)[0]
        tag = command.split("@", maxsplit=1)

        if len(tag) == 2:
            if tag[1] == "me":
                if not message.out:
                    return False
            elif tag[1].lower() != self._cached_username:
                return False
        elif (
            event.out
            or event.mentioned
            and event.message is not None
            and event.message.message is not None
            and f"@{self._cached_username}" not in event.message.message
        ):
            pass
        elif (
            not event.is_private
            and not self.no_nickname
            and not self._db.get(main.__name__, "no_nickname", False)
            and command not in self._db.get(main.__name__, "nonickcmds", [])
            and initiator not in self._db.get(main.__name__, "nonickusers", [])
            and utils.get_chat_id(event)
            not in self._db.get(main.__name__, "nonickchats", [])
        ):
            return False

        txt, func = self._modules.dispatch(tag[0])

        if (
            not func
            or not await self._handle_ratelimit(message, func)
            or not await self.security.check(message, func)
        ):
            return False

        if (
            message.is_channel
            and message.is_group
            and message.chat.title.startswith("hikka-")
            and message.chat.title != "hikka-logs"
        ):
            logging.warning("Ignoring message in datachat \\ logging chat")
            return False

        message.message = txt + message.message[len(command) :]

        if (
            f"{str(utils.get_chat_id(message))}.{func.__self__.__module__}"
            in blacklist_chats
            or whitelist_modules
            and f"{utils.get_chat_id(message)}.{func.__self__.__module__}"
            not in whitelist_modules
        ):
            return False

        if self._db.get(main.__name__, "grep", False):
            message = self._handle_grep(message)

        return message, prefix, txt, func

    async def handle_command(self, event: Message):
        """Handle all commands"""
        message = await self._handle_command(event)
        if not message:
            return

        message, prefix, _, func = message

        asyncio.ensure_future(
            self.future_dispatcher(
                func,
                message,
                self.command_exc,
                prefix,
            )
        )

    async def command_exc(self, e, message: Message, prefix: str):
        logging.exception("Command failed")
        if not self._db.get(main.__name__, "inlinelogs", True):
            try:
                txt = f"<b>🚫 Call</b> <code>{utils.escape_html(prefix)}{utils.escape_html(message.message)}</code><b> failed!</b>"
                await (message.edit if message.out else message.reply)(txt)
            except Exception:
                pass
            return

        try:
            exc = traceback.format_exc()
            # Remove `Traceback (most recent call last):`
            exc = "\n".join(exc.splitlines()[1:])
            txt = (
                f"<b>🚫 Call</b> <code>{utils.escape_html(prefix)}{utils.escape_html(message.message)}</code><b> failed!</b>\n\n"
                f"<b>🧾 Logs:</b>\n<code>{exc}</code>"
            )
            await (message.edit if message.out else message.reply)(txt)
        except Exception:
            pass

    async def watcher_exc(self, e, message: Message):
        logging.exception("Error running watcher")

    async def handle_incoming(self, event):
        """Handle all incoming messages"""
        message = utils.censor(getattr(event, "message", event))

        blacklist_chats = self._db.get(main.__name__, "blacklist_chats", [])
        whitelist_chats = self._db.get(main.__name__, "whitelist_chats", [])
        whitelist_modules = self._db.get(main.__name__, "whitelist_modules", [])

        if utils.get_chat_id(message) in blacklist_chats or (
            whitelist_chats and utils.get_chat_id(message) not in whitelist_chats
        ):
            logging.debug("Message is blacklisted")
            return

        for func in self._modules.watchers:
            bl = self._db.get(main.__name__, "disabled_watchers", {})
            modname = str(func.__self__.__class__.strings["name"])

            if (
                modname in bl
                and isinstance(message, types.Message)
                and (
                    "*" in bl[modname]
                    or utils.get_chat_id(message) in bl[modname]
                    or "only_chats" in bl[modname]
                    and message.is_private
                    or "only_pm" in bl[modname]
                    and not message.is_private
                    or "out" in bl[modname]
                    and not message.out
                    or "in" in bl[modname]
                    and message.out
                )
                or f"{str(utils.get_chat_id(message))}.{func.__self__.__module__}"
                in blacklist_chats
                or (
                    whitelist_modules
                    and (
                        f"{str(utils.get_chat_id(message))}." + func.__self__.__module__
                    )
                    not in whitelist_modules
                )
            ):
                logging.debug(f"Ignored watcher of module {modname}")
                continue

            # Avoid weird AttributeErrors in weird dochub modules by settings placeholder
            # of attributes
            for placeholder in {"text", "raw_text"}:
                try:
                    if not hasattr(event, placeholder):
                        setattr(event, placeholder, "")
                except UnicodeDecodeError:
                    logging.critical(
                        "Hikka issued error on updates\n"
                        "This is not your fault, please, report this issue in @hikka_talks along with info below:\n\n"
                        f"{type(event)=}, {event=}, {placeholder=}"
                    )

            # Run watcher via ensure_future so in case user has a lot
            # of watchers with long actions, they can run simultaneously
            asyncio.ensure_future(
                self.future_dispatcher(
                    func,
                    message,
                    self.watcher_exc,
                )
            )

    async def future_dispatcher(
        self,
        func: FunctionType,
        message: Message,
        exception_handler: FunctionType,
        *args,
    ):
        # Will be used to determine, which client caused logging messages
        # parsed via inspect.stack()
        _hikka_client_id_logging_tag = copy.copy(self.client._tg_id)  # skipcq
        try:
            await func(message)
        except BaseException as e:
            await exception_handler(e, message, *args)