Source code for embodichain.learning.rl.routing

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"""Trainer routing based on an algorithm's rollout semantics."""

from __future__ import annotations

from typing import Any, TypeAlias

from embodichain.learning.rl.algo import RolloutKind
from embodichain.learning.rl.differentiable_trainer import DifferentiableTrainer
from embodichain.learning.rl.utils.trainer import Trainer

__all__ = ["TrainerType", "get_trainer_class"]

TrainerType: TypeAlias = type[Trainer] | type[DifferentiableTrainer]




def get_trainer_class(algorithm: Any) -> TrainerType:
    """Return the trainer compatible with ``algorithm``."""
    rollout_kind = getattr(algorithm, "rollout_kind", RolloutKind.STANDARD)
    if rollout_kind == RolloutKind.DIFFERENTIABLE:
        return DifferentiableTrainer
    if rollout_kind == RolloutKind.STANDARD:
        return Trainer
    raise ValueError(f"Unsupported rollout kind: {rollout_kind!r}.")