"""
    This module hosts various agents that can participate in games.

    Examples of possible agents could be:

    - An online server
    - A locally running neural network
    - A hacker who participates from the terminal
    - A user interface that allows users to play against their own creations
"""

from dataclasses import dataclass
from typing import Any, Dict, Optional, Tuple, Union

import requests
import time

@dataclass(frozen=True)
class Agent:
    """
        Base class of a game participant. Mostly used to inherit from.
    """

    debug : bool
    games : dict[str, dict[str, Any]]
    profile : dict[str, Any]

    @classmethod
    def from_url(cls, url : str, **kwargs) -> "ServerAgent":
        """
            Create an agent based on a URL.

            :param url: The URL where the agent can be accessed.
            :type url: str            
            :return: An agent that contacts a server when polled.
            :rtype: ServerAgent
            :raises ValueError: The server fails to reach out one of the URLs.
        """
        try:
            return ServerAgent.from_server_url(url=url, **kwargs)
        except (ValueError, requests.RequestException, requests.HTTPError):
            pass

        raise ValueError(
            "URL did not lead to a willing agent"
        )

    @property
    def name(self) -> str:
        """
            The name by which the agent calls itself.
        """
        return str(self.profile.get("name", "Nameless agent"))

    def poll(
        self,
        game : str,
        payload : dict[str, Any],
        **kwargs
    ) -> Optional[dict[str, Any]]:
        """
            Ask the agent to make a move.

            :param game: The game the ServerAgent is asked to play.
            :type game: str
            :param payload: The JSON payload that represents the game's state.
            :type payload: dict[str, Any]
            :return: The agent's response, or None if the agent doesn't respond.
            :rtype: Optional[dict[str, Any]]
        """
        print(f"WARNING: The `poll` method is not defined on the {self.__class__.__name__} class")
        return None

@dataclass(frozen=True)
class ServerAgent(Agent):
    """
        Agent that reaches out to the internet to poll for moves.
    """

    url : str

    @classmethod
    def from_server_url(
        cls,
        url: str,
        timeout: float | tuple[float, float] | None = 10.0,
        debug : bool = False
    ) -> "ServerAgent":
        """
        Create a server agent by polling its discovery endpoint.

        :param url: The URL that the server can be reached at.
        :type url: str
        :param timeout: Request timeout.
        :type timeout: float | tuple[float, float] | None
        :param debug: Enables debug mode
        :type debug: bool
        :return: The server's representation as an agent.
        :rtype: ServerAgent
        :raises requests.exceptions.HTTPError: If the server returns a
            non-success HTTP status code.
        :raises requests.exceptions.RequestException: If the request fails
            before a response is received.
        :raises ValueError: If the response body is not a JSON object or if the
            payload contains malformed discovery fields.
        """
        response = requests.get(url.rstrip("/") + "/", timeout=timeout)
        response.raise_for_status()
        content = response.json()

        if not isinstance(content, dict):
            raise ValueError("Server discovery responses must be JSON objects.")

        raw_name = content.get("name", "")
        name = "" if raw_name is None else str(raw_name)

        games: dict[str, dict[str, Any]] = {}
        raw_games = content.get("games", {})
        if raw_games is not None:
            if not isinstance(raw_games, dict):
                raise ValueError("The 'games' field must be a JSON object when provided.")

            for game_name, profile in raw_games.items():
                if isinstance(profile, dict):
                    games[str(game_name)] = profile

        return cls(
            debug=debug,
            games=games,
            profile=content,
            url=url,
        )
    
    def poll(
        self,
        game : str,
        payload : dict[str, Any],
        **kwargs
    ) -> Optional[dict[str, Any]]:
        """
            Inquire a game to make a move.

            :param game: The game the ServerAgent is asked to play.
            :type game: str
            :param payload: The JSON payload that represents the game's state.
            :type payload: dict[str, Any]
            :return: The server's response, or None if the server did not respond.
            :rtype: Optional[dict[str, Any]]
        """
        url = f"{self.url.rstrip('/')}/{game.lstrip('/')}"
        timeout = float(kwargs.get("timeout", 1.0))

        try:
            response = requests.get(url, json=payload, timeout=timeout)
            response.raise_for_status()
            content = response.json()
        except (requests.exceptions.RequestException, ValueError):
            return None

        if self.debug:
            print(f"[DBG] Agent `{self.name}` returned:")
            print(content)

        return content if isinstance(content, dict) else None

    def to_dict(self) -> dict[str, Any]:
        """
            Represent the agent in the form of a dict.

            :return: Dictionary representation of the ServerAgent
            :rtype: dict[str, Any]
        """
        return dict(
            name=self.name,
            games=self.games,
            url=self.url,
            profile=self.profile,
        )