# Pyrogram - Telegram MTProto API Client Library for Python
# Copyright (C) 2017-2018 Dan Tès <https://github.com/delivrance>
#
# This file is part of Pyrogram.
#
# Pyrogram is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published
# by the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Pyrogram 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 Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with Pyrogram.  If not, see <http://www.gnu.org/licenses/>.

import time
from string import ascii_lowercase

from pyrogram import Client
from pyrogram.api.errors import FloodWait

"""This is an improved version of get_chat_members.py

Since Telegram will return at most 10.000 members for a single query, this script
repeats the search using numbers ("0" to "9") and all the available ascii letters ("a" to "z").

This can be further improved by also searching for non-ascii characters (e.g.: Japanese script),
as some user names may not contain ascii letters at all.
"""

app = Client("my_account")

target = "pyrogramchat"  # Target channel/supergroup
members = {}  # List that will contain all the members of the target chat
limit = 200  # Amount of users to retrieve for each API call (max 200)

# "" + "0123456789" + "abcdefghijklmnopqrstuvwxyz" (as list)
queries = [""] + [str(i) for i in range(10)] + list(ascii_lowercase)

with app:
    for q in queries:
        print('Searching for "{}"'.format(q))
        offset = 0  # For each query, offset restarts from 0

        while True:
            try:
                chunk = app.get_chat_members(target, offset, query=q)
            except FloodWait as e:  # Very large chats could trigger FloodWait
                print("Flood wait: {} seconds".format(e.x))
                time.sleep(e.x)  # When it happens, wait X seconds and try again
                continue

            if not chunk.chat_members:
                print('Done searching for "{}"'.format(q))
                print()
                break  # No more members left

            members.update({i.user.id: i for i in chunk.chat_members})
            offset += len(chunk.chat_members)

            print("Total members: {}".format(len(members)))

    print("Grand total: {}".format(len(members)))

# Now the "members" list contains all the members of the target chat