client.py

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the BSD-style license found in the
# LICENSE file in the root directory of this source tree.

"""FitScript Environment Client."""

from typing import Dict

from openenv.core import EnvClient
from openenv.core.client_types import StepResult
from openenv.core.env_server.types import State

from .models import FitscriptAction, FitscriptObservation


class FitscriptEnv(
    EnvClient[FitscriptAction, FitscriptObservation, State]
):
    """
    Client for the FitScript Fitness Prescription Environment.

    Maintains a persistent WebSocket connection to the environment server,
    enabling efficient multi-step interactions.

    Each client instance has its own dedicated environment session on the server.
    The server holds the task scenario and grader state; the client sends
    prescriptions and receives scored observations.

    Example — connect to a running server:
        >>> from FitScript import FitscriptAction, FitscriptEnv
        >>> env = FitscriptEnv(base_url="http://localhost:8000")
        >>> result = env.reset()
        >>> print(result.observation.client_scenario)
        >>> result = env.step(FitscriptAction(message="Your prescription here..."))
        >>> print(result.observation.feedback)
        >>> print(result.reward)
        >>> env.close()

    Example — launch from Docker image:
        >>> env = FitscriptEnv.from_docker_image("fitscript-env:latest")
        >>> try:
        ...     result = env.reset()
        ...     result = env.step(FitscriptAction(message="..."))
        ... finally:
        ...     env.close()
    """

    def _step_payload(self, action: FitscriptAction) -> Dict:
        """Convert FitscriptAction to JSON payload for the step message."""
        return {"message": action.message}

    def _parse_result(self, payload: Dict) -> StepResult[FitscriptObservation]:
        """Parse server response into StepResult[FitscriptObservation]."""
        obs_data = payload.get("observation", {})

        observation = FitscriptObservation(
            # Core echo
            echoed_message=obs_data.get("echoed_message", ""),

            # Task context
            task_id=obs_data.get("task_id", 1),
            task_description=obs_data.get("task_description", ""),
            client_scenario=obs_data.get("client_scenario", ""),

            # Grader feedback
            feedback=obs_data.get("feedback", ""),
            safety_score=obs_data.get("safety_score", 0.0),
            efficacy_score=obs_data.get("efficacy_score", 0.0),
            personalization_score=obs_data.get("personalization_score", 0.0),
            completeness_score=obs_data.get("completeness_score", 0.0),
            checks_passed=obs_data.get("checks_passed", []),
            checks_failed=obs_data.get("checks_failed", []),

            # Episode tracking
            step_number=obs_data.get("step_number", 0),
            max_steps=obs_data.get("max_steps", 3),

            # OpenEnv base fields
            done=payload.get("done", False),
            reward=payload.get("reward"),
            metadata=obs_data.get("metadata", {}),
        )

        return StepResult(
            observation=observation,
            reward=payload.get("reward"),
            done=payload.get("done", False),
        )

    def _parse_state(self, payload: Dict) -> State:
        """Parse server response into State object."""
        return State(
            episode_id=payload.get("episode_id"),
            step_count=payload.get("step_count", 0),
        )