
from datetime import datetime
from typing import Dict, Union

import zeebgram
from zeebgram import raw, utils
from zeebgram import types
from ..object import Object
from ..update import Update


class ChatMemberUpdated(Object, Update):
    """Represents changes in the status of a chat member.

    Parameters:
        chat (:obj:`~zeebgram.types.Chat`):
            Chat the user belongs to.

        from_user (:obj:`~zeebgram.types.User`):
            Performer of the action, which resulted in the change.

        date (:py:obj:`~datetime.datetime`):
            Date the change was done.

        old_chat_member (:obj:`~zeebgram.types.ChatMember`, *optional*):
            Previous information about the chat member.

        new_chat_member (:obj:`~zeebgram.types.ChatMember`, *optional*):
            New information about the chat member.

        invite_link (:obj:`~zeebgram.types.ChatInviteLink`, *optional*):
            Chat invite link, which was used by the user to join the chat; for joining by invite link events only.
    """

    def __init__(
        self,
        *,
        client: "zeebgram.Client" = None,
        chat: "types.Chat",
        from_user: "types.User",
        date: datetime,
        old_chat_member: "types.ChatMember",
        new_chat_member: "types.ChatMember",
        invite_link: "types.ChatInviteLink" = None,
    ):
        super().__init__(client)

        self.chat = chat
        self.from_user = from_user
        self.date = date
        self.old_chat_member = old_chat_member
        self.new_chat_member = new_chat_member
        self.invite_link = invite_link

    @staticmethod
    def _parse(
        client: "zeebgram.Client",
        update: Union["raw.types.UpdateChatParticipant", "raw.types.UpdateChannelParticipant"],
        users: Dict[int, "raw.types.User"],
        chats: Dict[int, "raw.types.Chat"]
    ) -> "ChatMemberUpdated":
        chat_id = getattr(update, "chat_id", None) or getattr(update, "channel_id")

        old_chat_member = None
        new_chat_member = None
        invite_link = None

        if update.prev_participant:
            old_chat_member = types.ChatMember._parse(client, update.prev_participant, users, chats)

        if update.new_participant:
            new_chat_member = types.ChatMember._parse(client, update.new_participant, users, chats)

        if update.invite:
            invite_link = types.ChatInviteLink._parse(client, update.invite, users)

        return ChatMemberUpdated(
            chat=types.Chat._parse_chat(client, chats[chat_id]),
            from_user=types.User._parse(client, users[update.actor_id]),
            date=utils.timestamp_to_datetime(update.date),
            old_chat_member=old_chat_member,
            new_chat_member=new_chat_member,
            invite_link=invite_link,
            client=client
        )
