#  Pyrogram - Telegram MTProto API Client Library for Python
#  Copyright (C) 2017-2020 Dan <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 logging
from datetime import datetime
from time import perf_counter

log = logging.getLogger(__name__)


class MsgId:
    reference_clock = 0
    last_time = 0
    msg_id_offset = 0
    server_time = 0

    def __new__(cls) -> int:
        now = perf_counter() - cls.reference_clock + cls.server_time
        cls.msg_id_offset = cls.msg_id_offset + 4 if now == cls.last_time else 0
        msg_id = int(now * 2 ** 32) + cls.msg_id_offset
        cls.last_time = now

        return msg_id

    @classmethod
    def set_server_time(cls, server_time: int):
        if not cls.server_time:
            cls.reference_clock = perf_counter()
            cls.server_time = server_time
            log.info(f"Time synced: {datetime.utcfromtimestamp(server_time)} UTC")