"""Method Registry — built-in steering methods (AP1.0)."""

from __future__ import annotations

from dataclasses import dataclass

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


@dataclass(frozen=True)
class MethodDefinition:
    key: str
    version: str
    description: str
    default_lifecycle_steps: tuple[str, ...]


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()