from __future__ import annotations

import typing

from .. import operator
from langbot_plugin.api.entities.builtin.command import context as command_context, errors as command_errors


@operator.operator_class(name='resend', help='重发当前会话的最后一条消息', usage='!resend')
class ResendOperator(operator.CommandOperator):
    async def execute(
        self, context: command_context.ExecuteContext
    ) -> typing.AsyncGenerator[command_context.CommandReturn, None]:
        # 回滚到最后一条用户message前
        if context.session.using_conversation is None:
            yield command_context.CommandReturn(error=command_errors.CommandError('当前没有对话'))
        else:
            conv_msg = context.session.using_conversation.messages

            # 倒序一直删到最后一条用户message
            while len(conv_msg) > 0 and conv_msg[-1].role != 'user':
                conv_msg.pop()

            if len(conv_msg) > 0:
                # 删除最后一条用户message
                conv_msg.pop()

            # 不重发了，提示用户已删除就行了
            yield command_context.CommandReturn(text='已删除最后一次请求记录')