#!/usr/bin/env python3

import logging
import os
import re
import traceback
from datetime import datetime, timedelta
from hashlib import sha1
from html import escape
from queue import Queue, Empty
from time import sleep
from threading import Thread, Event
from typing import Dict, List

import sentry_sdk
from redis import Redis
from telegram.error import Unauthorized, TelegramError
from telegram.ext import Updater, CommandHandler, MessageHandler, Filters, CallbackQueryHandler, CallbackContext
from telegram import Message, Update, Bot, InlineKeyboardMarkup, InlineKeyboardButton, User, InputMediaPhoto, \
    InputMediaVideo, InputMediaAnimation, InputMediaAudio, InputMediaDocument, PhotoSize

from config import BOT_TOKEN, SENTRY_DSN, MANAGEMENT_CHAT, DEBUG
from db import get_conn, Subscriber, commit
from send_users_list import send_users_list

logging.basicConfig(level=logging.WARNING)
queue = Queue()
sentry_sdk.init(dsn=SENTRY_DSN)
conn = get_conn()
redis = Redis()

MAX_MESSAGE_LENGTH = 4096
MAX_CAPTION_LENGTH = 1024


def _antispam(args):
    if not args:
        return True
    args = '|'.join(map(str, args))
    digest = sha1(args.encode()).digest()
    key = 'lono-' + digest.hex()
    if redis.get(key):
        return False
    redis.set(key, '1', ex=30)
    return True


def _notify_access_request(bot: Bot, user: User):
    markup = InlineKeyboardMarkup([[InlineKeyboardButton('Добавить', callback_data=f'add {user.id}')]])
    bot.send_message(MANAGEMENT_CHAT, f'<a href="tg://user?id={user.id}">{escape(user.full_name)}</a> запросил доступ',
                     parse_mode='html', reply_markup=markup)


def welcome(update: Update, ctx: CallbackContext):
    if DEBUG:
        _add_user(ctx.bot, update.effective_user.id)
        update.message.reply_text('Добро пожаловать (debug)')
        return

    if update.effective_user.id in conn.root.subscribers:
        update.message.reply_text('Вы уже являетесь участником ЛОНО')
    else:
        update.message.reply_text('Пожалуйста, обратитесь к @lono_contactbot')
        _notify_access_request(ctx.bot, update.message.from_user)


def unsubscribe(update: Update, ctx: CallbackContext):
    user = _remove_user(update.message.chat_id)
    update.message.reply_text('Вы были отписаны от бота. '
                              'Обратитесь к @lono_contactbot если вы хотите подписаться снова.')
    ctx.bot.send_message(MANAGEMENT_CHAT, f'<a href="tg://user?id={user.id}">{escape(user.name)}</a> отписался')


def _add_user(bot, uid):
    user = conn.root.subscribers[uid] = Subscriber.from_chat(bot.get_chat(uid))
    commit()
    return user


def add_user(update: Update, ctx: CallbackContext):
    if update.callback_query:
        update.callback_query.answer()

    if ctx.match:
        if update.callback_query.message.chat.id != MANAGEMENT_CHAT:
            return
        uid = ctx.match.group(1)
    elif ctx.args:
        uid = ctx.args[0]
    elif update.message and update.message.reply_to_message and update.message.reply_to_message.forward_from:
        uid = update.message.reply_to_message.forward_from.id
    else:
        return ctx.bot.send_message(MANAGEMENT_CHAT, 'Укажите ID пользователя или ответьте на его сообщение')

    try:
        uid = int(uid)
    except (ValueError, TypeError):
        pass

    try:
        user = _add_user(ctx.bot, uid)
        if update.callback_query:
            update.callback_query.message.edit_reply_markup()
        ctx.bot.send_message(MANAGEMENT_CHAT, f'<a href="tg://user?id={uid}">{escape(user.name)}</a> был добавлен',
                             parse_mode='html')
        ctx.bot.send_message(uid, 'Добро пожаловать. Снова.')
    except TelegramError as e:
        ctx.bot.send_message(MANAGEMENT_CHAT, str(e))


def _remove_user(uid):
    user = conn.root.subscribers[uid]
    del conn.root.subscribers[uid]
    commit()
    return user


def remove_user(update: Update, ctx: CallbackContext):
    if update.callback_query:
        update.callback_query.answer()

    if ctx.match:
        if update.callback_query.message.chat.id != MANAGEMENT_CHAT:
            return
        uid = ctx.match.groups(1)
    elif ctx.args:
        uid = ctx.args[0]
    elif update.message and update.message.reply_to_message and update.message.reply_to_message.forward_from:
        uid = update.message.reply_to_message.forward_from.id
    else:
        return ctx.bot.send_message(MANAGEMENT_CHAT, 'Укажите ID пользователя или ответьте на его сообщение')

    try:
        uid = int(uid)
    except (ValueError, TypeError):
        pass

    try:
        user = _remove_user(uid)
        ctx.bot.send_message(MANAGEMENT_CHAT, f'<a href="tg://user?id={uid}">{escape(user.name)}</a> был удален',
                             parse_mode='html')
        if update.callback_query:
            update.callback_query.message.edit_reply_markup()
    except KeyError:
        ctx.bot.send_message(MANAGEMENT_CHAT, f'Пользователь id={uid} не был найден')


def users(update: Update, ctx: CallbackContext):
    send_users_list()


def msg(update: Update, ctx: CallbackContext):
    queue.put(update.message)


def _sign_text(text, m: Message, limit):
    if not text:
        text = ''

    text = re.sub(r'<a href="(tg://.*?)">.*?</a>', '<a href="\\1">\\1</a>', text)

    sign = ''
    if text.startswith('!sign') or text.startswith('/sign'):
        text = text[5:]
        sign = f'\n\n— <a href="tg://user?id={m.from_user.id}">{escape(m.from_user.full_name)}</a>'

    return text[:limit - len(sign)] + sign


def _process_media_group(bot: Bot, messages: List[Message]):
    if not messages:
        return

    m = messages[0]

    current_chat = m.chat_id
    users = conn.root.subscribers  # type: Dict[int, Subscriber]
    if current_chat not in users:
        if DEBUG:
            _add_user(bot, current_chat)
            m.reply_text('Добро пожаловать (debug)')
        else:
            _notify_access_request(bot, m.from_user)
            return m.reply_text('Пожалуйста, обратитесь к @lono_contactbot')

    reply_to_message_internal_id = None
    if m.reply_to_message and m.reply_to_message.message_id in users[current_chat].messages_forward:
        reply_to_message_internal_id = users[current_chat].messages_forward[m.reply_to_message.message_id]

    media_group = []
    for message in messages:
        caption = _sign_text(message.caption_html, message, MAX_CAPTION_LENGTH)

        if hasattr(message, 'photo') and message.photo:
            media_group.append(InputMediaPhoto(message.photo[-1].file_id, caption=caption, parse_mode='html'))
        elif hasattr(message, 'video') and message.video:
            media_group.append(InputMediaVideo(message.video.file_id, caption=caption, parse_mode='html'))
        elif hasattr(message, 'animation') and message.animation:
            media_group.append(InputMediaAnimation(message.animation.file_id, caption=caption, parse_mode='html'))
        elif hasattr(message, 'document') and message.document:
            media_group.append(InputMediaDocument(message.document.file_id, caption=caption, parse_mode='html'))
        elif hasattr(message, 'audio') and message.audio:
            media_group.append(InputMediaAudio(message.audio.file_id, caption=caption, parse_mode='html'))

    remove_uids = []

    for uid, user in users.items():
        sleep(.02)

        reply_to_message_id = None
        if reply_to_message_internal_id:
            reply_to_message_id = user.messages_reverse.get(reply_to_message_internal_id, None)

        try:
            sent_messages = bot.send_media_group(uid, media_group, reply_to_message_id=reply_to_message_id)
            if sent_messages:
                user.update_from_message(sent_messages[0])
                for r in sent_messages:
                    user.messages_forward[r.message_id] = conn.root.counter
                    user.messages_reverse[conn.root.counter] = r.message_id
        except Unauthorized:
            remove_uids.append(uid)
            bot.send_message(MANAGEMENT_CHAT, f'<a href="tg://user?id={uid}">{user.name}</a> был удален '
                                              f'из-за блокировки бота', parse_mode='html')
        except Exception:
            traceback.print_exc()
            sentry_sdk.capture_exception()
    conn.root.counter += len(messages)
    commit()
    for uid in remove_uids:
        _remove_user(uid)


def users_list(update: Update, ctx: CallbackContext):
    current_chat = update.effective_chat.id
    subs = conn.root.subscribers  # type: Dict[int, Subscriber]
    if current_chat not in subs:
        return

    messages = [f'Count: {len(subs)}\n']
    for sub in subs.values():  # type: Subscriber
        msg = f'<code>{sub.uid:>14}</code> '
        if sub.uid < 0:
            msg += str(sub.name)
        else:
            msg += f'<a href="tg://user?id={sub.uid}">{sub.name}</a>'
        messages.append(msg)

    for i in range(0, len(messages), 40):
        update.effective_message.reply_text('\n'.join(messages[i:i+40]), parse_mode='html')


def _process_message(bot: Bot, m: Message):
    if m.sticker or m.animation:
        delta = datetime.now() - conn.root.last_media
        if delta < timedelta(seconds=15):
            bot.send_message(
                m.from_user.id,
                'Не вайпи, до следующей гифки/стикера осталось {} секунд'.format(15 - int(delta.total_seconds()))
            )
            return
        conn.root.last_media = datetime.now()
        commit()
    current_chat = m.chat_id
    users = conn.root.subscribers  # type: Dict[int, Subscriber]
    if current_chat not in users:
        if DEBUG:
            _add_user(bot, current_chat)
            m.reply_text('Добро пожаловать (debug)')
        else:
            _notify_access_request(bot, m.from_user)
            return m.reply_text('Пожалуйста, обратитесь к @lono_contactbot')

    text = _sign_text(m.text_html, m, MAX_MESSAGE_LENGTH)
    caption = _sign_text(m.caption_html, m, MAX_CAPTION_LENGTH)

    reply_to_message_internal_id = None
    if m.reply_to_message and m.reply_to_message.message_id in users[current_chat].messages_forward:
        reply_to_message_internal_id = users[current_chat].messages_forward[m.reply_to_message.message_id]

    func = None
    args = []
    hash_args = None
    kwargs = {}
    if m.forward_date:
        func = m.forward
    elif hasattr(m, 'audio') and m.audio:
        a = m.audio
        func = bot.send_audio
        args = [a.file_id, a.duration, a.performer, a.title, caption]
        kwargs = dict(parse_mode='html')
    elif hasattr(m, 'document') and m.document:
        d = m.document
        func = bot.send_document
        args = [d.file_id, d.file_name, caption]
        kwargs = dict(parse_mode='html')
    elif hasattr(m, 'photo') and m.photo:
        p = m.photo
        func = bot.send_photo
        args = [p[-1].file_id, caption]
        hash_args = [p[-1].file_unique_id, caption]
        kwargs = dict(parse_mode='html')
    elif hasattr(m, 'sticker') and m.sticker:
        s = m.sticker
        func = bot.send_sticker
        args = [s.file_id]
    elif hasattr(m, 'video') and m.video:
        v = m.video
        func = bot.send_video
        args = [v.file_id, v.duration, caption]
        kwargs = dict(parse_mode='html')
    elif hasattr(m, 'voice') and m.voice:
        v = m.voice
        func = bot.send_voice
        args = [v.file_id, v.duration, caption]
        kwargs = dict(parse_mode='html')
    elif hasattr(m, 'video_note') and m.video_note:
        vn = m.video_note
        func = bot.send_video_note
        args = [vn.file_id, vn.duration, vn.length]
    elif hasattr(m, 'contact') and m.contact:
        c = m.contact
        func = bot.send_contact
        args = [c.phone_number, c.first_name, c.last_name]
    elif hasattr(m, 'location') and m.location:
        l = m.location
        func = bot.send_location
        args = [l.latitude, l.longitude]
    elif hasattr(m, 'venue') and m.venue:
        v = m.venue
        l = v.location
        func = bot.send_venue
        args = [l.latitude, l.longitude, v.title, v.address, v.foursquare_id]
    elif hasattr(m, 'text') and m.text:
        func = bot.send_message
        args = [text, 'html']

    if not _antispam(hash_args or args):
        return m.reply_text('Не вайпи', quote=True)

    remove_uids = []

    if func:
        for uid, user in users.items():
            sleep(.02)

            reply_to_message_id = None
            if reply_to_message_internal_id:
                reply_to_message_id = user.messages_reverse.get(reply_to_message_internal_id, None)

            try:
                r = func(*([uid] + args), **kwargs, reply_to_message_id=reply_to_message_id)
                if r:
                    user.update_from_message(r)
                    user.messages_forward[r.message_id] = conn.root.counter
                    user.messages_reverse[conn.root.counter] = r.message_id
            except Unauthorized:
                remove_uids.append(uid)
                bot.send_message(MANAGEMENT_CHAT, f'<a href="tg://user?id={uid}">{user.name}</a> был удален '
                                                  f'из-за блокировки бота', parse_mode='html')
            except Exception:
                traceback.print_exc()
                sentry_sdk.capture_exception()
    conn.root.counter += 1
    commit()
    for uid in remove_uids:
        _remove_user(uid)


def task_queue(u: Updater, stop_signal: Event):
    while True:
        if not u.running or stop_signal.is_set():
            return

        try:
            m = queue.get(timeout=1)  # type: Message
            if m.media_group_id:
                media_group_id = m.media_group_id
                group_messages = [m]
                while queue.qsize() and queue.queue[0].media_group_id == media_group_id:
                    group_messages.append(queue.get(block=False))
                _process_media_group(u.bot, group_messages)
            else:
                _process_message(u.bot, m)
        except Empty:
            pass
        except:
            traceback.print_exc()
            sentry_sdk.capture_exception()


def main():
    updater = Updater(BOT_TOKEN, workers=4, use_context=True)

    updater.dispatcher.add_handler(CommandHandler('start', welcome, Filters.private))
    updater.dispatcher.add_handler(CommandHandler('stop', unsubscribe, Filters.private))
    updater.dispatcher.add_handler(CommandHandler('add', add_user, Filters.chat(MANAGEMENT_CHAT), pass_args=True))
    updater.dispatcher.add_handler(CallbackQueryHandler(add_user, pattern=r'^add (\d+)$'))
    updater.dispatcher.add_handler(CommandHandler('remove', remove_user, Filters.chat(MANAGEMENT_CHAT), pass_args=True))
    updater.dispatcher.add_handler(CallbackQueryHandler(remove_user, pattern=r'^remove (\d+)$'))
    updater.dispatcher.add_handler(CommandHandler('users', users_list, Filters.private))
    updater.dispatcher.add_handler(MessageHandler(Filters.private, msg))

    updater.start_polling()

    stop_signal = Event()
    tq = Thread(target=task_queue, args=(updater, stop_signal))
    tq.start()

    logging.warning('LONO has started')
    updater.idle()
    stop_signal.set()
    logging.warning('LONO is stopping...')
    commit()
    conn.close()


if __name__ == '__main__':
    main()