"""Method Registry — built-in steering methods."""

from __future__ import annotations

from dataclasses import dataclass
from typing import Literal

_METHODS: dict[str, "MethodDefinition"] = {}


@dataclass(frozen=True)
class MethodDefinition:
    key: str
    version: str
    label: str
    description: str
    default_lifecycle_steps: tuple[str, ...]
    next_action_strategy_key: str = "default"
    data_slices: frozenset[str] = frozenset()
    compatible_archetype_keys: frozenset[str] | Literal["*"] = "*"


def method_compatible_with_archetype(
    method: MethodDefinition, archetype_key: str
) -> bool:
    compat = method.compatible_archetype_keys
    if compat == "*":
        return True
    return archetype_key in compat


def register_method(defn: MethodDefinition) -> None:
    if defn.key in _METHODS:
        raise ValueError(f"Method already registered: {defn.key}")
    _METHODS[defn.key] = defn


def get_method(key: str) -> MethodDefinition | None:
    return _METHODS.get(key)


def list_methods() -> tuple[MethodDefinition, ...]:
    return tuple(_METHODS.values())


def clear_methods_for_tests() -> None:
    _METHODS.clear()