# mautrix-amp - A very hacky Matrix-SMS bridge based on using Android Messages for Web in Puppeteer
# Copyright (C) 2020 Tulir Asokan
#
# 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/>.
from typing import Dict, List, Optional, AsyncGenerator, TYPE_CHECKING, cast
import asyncio

from mautrix.bridge import BaseUser
from mautrix.types import UserID, RoomID
from mautrix.appservice import AppService, IntentAPI

from .db import User as DBUser, Portal as DBPortal, Message as DBMessage
from .config import Config
from .rpc import Client, Message
from . import puppet as pu, portal as po

if TYPE_CHECKING:
    from .__main__ import MessagesBridge


class User(DBUser, BaseUser):
    by_mxid: Dict[UserID, 'User'] = {}
    config: Config
    az: AppService
    loop: asyncio.AbstractEventLoop

    client: Optional[Client]
    intent: Optional[IntentAPI]
    is_real_user = True

    _notice_room_lock: asyncio.Lock

    def __init__(self, mxid: UserID, notice_room: Optional[RoomID] = None) -> None:
        super().__init__(mxid=mxid, notice_room=notice_room)
        self._notice_room_lock = asyncio.Lock()
        self.is_whitelisted = self.is_admin = self.config["bridge.user"] == mxid
        self.log = self.log.getChild(self.mxid)
        self.client = None
        self.username = None
        self.intent = None

    @classmethod
    def init_cls(cls, bridge: 'MessagesBridge') -> None:
        cls.config = bridge.config
        cls.az = bridge.az
        cls.loop = bridge.loop
        Client.config = bridge.config

    async def is_logged_in(self) -> bool:
        try:
            return self.client and (await self.client.start()).is_logged_in
        except Exception:
            return False

    async def try_connect(self) -> None:
        try:
            await self.connect()
        except Exception:
            self.log.exception("Error while connecting to puppeteer script")

    async def connect_double_puppet(self) -> None:
        self.log.debug("Trying to log in with shared secret")
        try:
            access_token = await pu.Puppet._login_with_shared_secret(self.mxid)
            if not access_token:
                self.log.warning("Failed to log in with shared secret")
                return
            self.log.debug("Logged in with shared secret")
            self.intent = self.az.intent.user(self.mxid, access_token)
        except Exception:
            self.log.exception("Error logging in with shared secret")

    async def connect(self) -> None:
        self.loop.create_task(self.connect_double_puppet())
        self.client = Client(self.mxid)
        self.log.debug("Starting client")
        state = await self.client.start()
        await self.client.on_message(self.handle_message)
        if state.is_logged_in:
            self.loop.create_task(self._try_sync())

    async def _try_sync(self) -> None:
        try:
            await self.sync()
        except Exception:
            self.log.exception("Exception while syncing")

    async def sync(self) -> None:
        await self.client.set_last_message_ids(await DBMessage.get_max_mids())
        self.log.info("Syncing chats")
        chats = await self.client.get_chats()
        limit = self.config["bridge.initial_conversation_sync"]
        for index, chat in enumerate(chats):
            portal = await po.Portal.get_by_chat_id(chat.id, create=True)
            if portal.mxid or index < limit:
                chat = await self.client.get_chat(chat.id)
                if portal.mxid:
                    await portal.update_matrix_room(self, chat)
                    await portal.backfill(self)
                else:
                    await portal.create_matrix_room(self, chat)

    async def stop(self) -> None:
        if self.client:
            await self.client.stop()

    async def get_direct_chats(self) -> Dict[UserID, List[RoomID]]:
        return {
            pu.Puppet.get_mxid_from_id(portal.other_user): [portal.mxid]
            for portal in await DBPortal.find_private_chats()
            if portal.mxid
        }

    async def handle_message(self, evt: Message) -> None:
        self.log.trace("Received message %s", evt)
        portal = await po.Portal.get_by_chat_id(evt.chat_id, create=True)
        if not portal.mxid:
            chat_info = await self.client.get_chat(evt.chat_id)
            await portal.create_matrix_room(self, chat_info)
        await portal.handle_remote_message(self, evt)

    def _add_to_cache(self) -> None:
        self.by_mxid[self.mxid] = self

    @classmethod
    async def get_by_mxid(cls, mxid: UserID, create: bool = True) -> Optional['User']:
        try:
            return cls.by_mxid[mxid]
        except KeyError:
            pass

        user = cast(cls, await super().get_by_mxid(mxid))
        if user is not None:
            user._add_to_cache()
            return user

        if create:
            user = cls(mxid)
            await user.insert()
            user._add_to_cache()
            return user

        return None