#  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 typing import List

from pyrogram import raw
from pyrogram import types
from pyrogram import utils
from pyrogram.scaffold import Scaffold

log = logging.getLogger(__name__)


class GetDialogs(Scaffold):
    async def get_dialogs(
        self,
        offset_date: int = 0,
        limit: int = 100,
        pinned_only: bool = False
    ) -> List["types.Dialog"]:
        """Get a chunk of the user's dialogs.

        You can get up to 100 dialogs at once.
        For a more convenient way of getting a user's dialogs see :meth:`~pyrogram.Client.iter_dialogs`.

        Parameters:
            offset_date (``int``):
                The offset date in Unix time taken from the top message of a :obj:`~pyrogram.types.Dialog`.
                Defaults to 0. Valid for non-pinned dialogs only.

            limit (``str``, *optional*):
                Limits the number of dialogs to be retrieved.
                Defaults to 100. Valid for non-pinned dialogs only.

            pinned_only (``bool``, *optional*):
                Pass True if you want to get only pinned dialogs.
                Defaults to False.

        Returns:
            List of :obj:`~pyrogram.types.Dialog`: On success, a list of dialogs is returned.

        Example:
            .. code-block:: python

                # Get first 100 dialogs
                app.get_dialogs()

                # Get pinned dialogs
                app.get_dialogs(pinned_only=True)
        """

        if pinned_only:
            r = await self.send(
                raw.functions.messages.GetPinnedDialogs(folder_id=0),
                sleep_threshold=60
            )
        else:
            r = await self.send(
                raw.functions.messages.GetDialogs(
                    offset_date=offset_date,
                    offset_id=0,
                    offset_peer=raw.types.InputPeerEmpty(),
                    limit=limit,
                    hash=0,
                    exclude_pinned=True
                ),
                sleep_threshold=60
            )

        users = {i.id: i for i in r.users}
        chats = {i.id: i for i in r.chats}

        messages = {}

        for message in r.messages:
            if message.empty:
                continue
            
            peer_id = message.peer_id

            if isinstance(peer_id, raw.types.PeerUser):
                if message.out:
                    chat_id = peer_id.user_id
                else:
                    chat_id = utils.get_raw_peer_id(message.from_id)
            else:
                chat_id = utils.get_peer_id(peer_id)

            messages[chat_id] = await types.Message._parse(self, message, users, chats)

        parsed_dialogs = []

        for dialog in r.dialogs:
            if not isinstance(dialog, raw.types.Dialog):
                continue

            parsed_dialogs.append(types.Dialog._parse(self, dialog, messages, users, chats))

        return types.List(parsed_dialogs)