#!/usr/bin/env python3

import asyncio
import os
import json
import glob
import traceback
import importlib
import sys
import re
from nio import (AsyncClient, RoomMessageText, RoomMessageUnknown, JoinError, InviteEvent)


class Bot:
    client = None
    join_on_invite = False
    modules = dict()

    async def send_text(self, room, body):
        msg = {
            "body": body,
            "msgtype": "m.text"
        }
        await self.client.room_send(self.get_room_id(room), 'm.room.message', msg)

    def get_room_id(self, room):
        for roomid in self.client.rooms:
            if self.client.rooms[roomid].named_room_name() == room.named_room_name():
                return roomid
        print('Cannot find id for room', room.named_room_name(), ' - is the bot on it?')
        return None

    async def message_cb(self, room, event):
        # Figure out the command
        body = event.body
        if len(body) == 0:
            return
        command = body.split().pop(0)

        # Strip away non-alphanumeric characters, including leading ! for security
        command = re.sub(r'\W+', '', command)

        moduleobject = self.modules.get(command)

        if "matrix_message" in dir(moduleobject):
            try:
                await moduleobject.matrix_message(bot, room, event)
            except:
                await self.send_text(room, f'Module {command} experienced difficulty: {sys.exc_info()[0]} - see log for details')
                traceback.print_exc(file=sys.stderr)

    async def unknown_cb(self, room, event):
        if event.msgtype != 'm.location':
            return
        pass

    async def invite_cb(self, room, event):
        for attempt in range(3):
            result = await self.client.join(room.room_id)
            if type(result) == JoinError:
                print(f"Error joining room {room.room_id} (attempt %d): %s",
                    attempt, result.message,
                )
            else:
                break

    def load_module(self, modulename):
        try:
            module = importlib.import_module('modules.' + modulename)
            cls = getattr(module, 'MatrixModule')
            return cls()
        except ModuleNotFoundError:
            print('Module ', modulename, ' failed to load!')
            traceback.print_exc(file=sys.stderr)
            return None

    def get_modules(self):
        modulefiles = glob.glob('./modules/*.py')

        for modulefile in modulefiles:
            modulename = os.path.splitext(os.path.basename(modulefile))[0]
            moduleobject = self.load_module(modulename)
            if moduleobject:
                self.modules[modulename] = moduleobject

    def init(self):
        self.client = AsyncClient(os.environ['MATRIX_SERVER'], os.environ['MATRIX_USER'])
        self.client.access_token = os.getenv('MATRIX_ACCESS_TOKEN')
        self.join_on_invite = os.getenv('JOIN_ON_INVITE')

        self.get_modules()

        print(f'Starting {len(self.modules)} modules..')

        for modulename, moduleobject in self.modules.items():
            print(modulename + '..')
            if "matrix_start" in dir(moduleobject):
                try:
                    moduleobject.matrix_start(bot)
                except:
                    traceback.print_exc(file=sys.stderr)
    
    def stop(self):
        print(f'Stopping {len(self.modules)} modules..')
        for modulename, moduleobject in self.modules.items():
            print(modulename + '..')
            if "matrix_stop" in dir(moduleobject):
                try:
                    moduleobject.matrix_stop(bot)
                except:
                    traceback.print_exc(file=sys.stderr)

    async def run(self):
        if not self.client.access_token:
            await self.client.login(os.environ['MATRIX_PASSWORD'])
            print("Logged in with password, access token:", self.client.access_token)

        await self.client.sync()

        if self.client.logged_in:
            self.client.add_event_callback(self.message_cb, RoomMessageText)
            self.client.add_event_callback(self.unknown_cb, RoomMessageUnknown)
            if self.join_on_invite:
                print('Note: Bot will join rooms if invited')
                self.client.add_event_callback(self.invite_cb, (InviteEvent,))
            print('Bot running')
            await self.client.sync_forever(timeout=30000)
        else:
            print('Client was not able to log in, check env variables!')


bot = Bot()
bot.init()
try:
    asyncio.get_event_loop().run_until_complete(bot.run())
except KeyboardInterrupt:
    pass
bot.stop()