import sys
from getpass import getpass
from time import sleep

from telethon import TelegramClient
from telethon.errors import SessionPasswordNeededError
from telethon.errors.rpcerrorlist import UsernameNotOccupiedError
from telethon.errors.rpcerrorlist import FloodWaitError
from telethon.tl.functions.channels import GetParticipantsRequest
from telethon.tl.functions.contacts import ResolveUsernameRequest
from telethon.tl.types import ChannelParticipantsSearch, InputChannel

import asyncio
from aioconsole import ainput

from config import app_api_id as api_id, app_api_hash as api_hash, app_phone as phone
#api_id = 149999999
#api_hash = '69cagfbda82fe3d17b3becxa20817d'
#phone = '+79777777777'
limit = 100


async def get_chat_info(username, client):
    try:
        chat = await client(ResolveUsernameRequest(username))
    except UsernameNotOccupiedError:
        print('Chat/channel not found!')
        sys.exit()
    print (chat)
    result = {
        'chat_id': chat.chats[0].id, #-12013214989,
        'access_hash': chat.chats[0].access_hash
    }
    return result


async def dump_users(chat, client):
    counter = 0
    offset = 0
    chat_object = InputChannel(chat['chat_id'], chat['access_hash'])
    all_participants = []
    print('Process...')
    while True:
        participants = await client(GetParticipantsRequest(
                    chat_object, ChannelParticipantsSearch(''), offset, limit, hash=chat['access_hash']
                ))
        if not participants.users:
            break
        all_participants.extend(['{} {}'.format(x.id, x.username)
                           for x in participants.users])
        users_count = len(participants.users)
        offset += users_count
        counter += users_count
        print('{} users collected'.format(counter))
        sleep(2)
    with open('users.txt', 'w') as file:
        file.write('\n'.join(map(str, all_participants)))


async def main():
    channel_name = await ainput('Input a channel name, without "@": ')
    client = TelegramClient('client-session', api_id, api_hash)
    print('Connecting...')
    await client.connect()
    if not await client.is_user_authorized():
        try:
            await client.send_code_request(phone)
            print('Sending a code...')
            await client.sign_in(phone, code=await ainput('Enter code: '))
            print('Successfully!')
        except FloodWaitError as FloodError:
            print('Flood wait: {}.'.format(FloodError))
            return
        except SessionPasswordNeededError:
            await client.sign_in(password=getpass('Enter password: '))
            print('Successfully!')
    await dump_users(await get_chat_info(channel_name, client), client)
    print('Done!')

if __name__ == '__main__':
    asyncio.run(main())