from typing import NamedTuple, Union
from enum import Enum

import abc


class AgentAction(NamedTuple):
    """Agent's action to take."""

    tool: str
    tool_input: Union[str, dict]
    log: str


class AgentFinish(NamedTuple):
    """Agent's return value."""

    return_values: dict
    log: str


class AgentCriticism(NamedTuple):
    """Agent's criticism."""

    is_agree: bool
    criticism: str
    sender_agent: object = None


class AGENT_TYPES(Enum):
    ROLE_ASSIGNMENT = 0
    SOLVER = 1
    CRITIC = 2
    EXECUTION = 3
    EVALUATION = 4
    MANAGER = 5


class Singleton(abc.ABCMeta, type):
    """
    Singleton metaclass for ensuring only one instance of a class.
    """

    _instances = {}

    def __call__(cls, *args, **kwargs):
        """Call method for the singleton metaclass."""
        if cls not in cls._instances:
            cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs)
        return cls._instances[cls]