"""Provider registry: map a provider name to a model factory and preset models.

Each provider declares its default model plus the small/large presets the
``iterate`` / ``validate`` CLI loops fall back to, and a ``make_model`` factory that
reads credentials lazily (so importing a provider never requires a key).
"""

from collections.abc import Callable
from dataclasses import dataclass

from langchain_core.language_models import BaseChatModel


@dataclass(frozen=True)
class Provider:
    """A model provider: presets plus a name-to-model factory."""

    name: str
    default_model: str
    small_model: str
    large_model: str
    make_model: Callable[[str], BaseChatModel]


_REGISTRY: dict[str, Provider] = {}


def register(provider: Provider) -> None:
    """Register ``provider`` under its name (overwriting any existing entry)."""
    _REGISTRY[provider.name] = provider


def get_provider(name: str) -> Provider:
    """Return the registered provider named ``name`` or raise ``KeyError``."""
    if name not in _REGISTRY:
        available = ", ".join(sorted(_REGISTRY)) or "(none registered)"
        raise KeyError(f"Unknown provider '{name}'. Available: {available}")
    return _REGISTRY[name]


def provider_names() -> list[str]:
    """Return the sorted names of all registered providers."""
    return sorted(_REGISTRY)


# Import built-in providers for their registration side effects.
from skill_eval_runner.providers import anthropic, bedrock_claude  # noqa: E402,F401