# 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.

"""Constraint Env Environment Client."""

from typing import Dict

from openenv.core import EnvClient
from openenv.core.client_types import StepResult


from .models import ConstraintAction, ConstraintObservation, ConstraintState


class ConstraintEnv(
    EnvClient[ConstraintAction, ConstraintObservation, ConstraintState]
):
    """
    Client for the Constraint Env Environment.

    This client maintains a persistent WebSocket connection to the environment server,
    enabling efficient multi-step interactions with lower latency.
    Each client instance has its own dedicated environment session on the server.

    """

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

    def _parse_result(self, payload: Dict) -> StepResult[ConstraintObservation]:
        """
        Parse server response into StepResult[ConstraintObservation].
        """
        
        if isinstance(payload, str):
            raise ValueError(f"Server returned an error string instead of JSON: {payload}")
            
        obs_data = payload.get("observation", {})
        if isinstance(obs_data, str):
            obs_data = {}
            
        observation = ConstraintObservation(
            prompt=obs_data.get("prompt", ""),
            info=obs_data.get("info", {}),           # FIX: Changed from 0 to {}
            done=payload.get("done", False),
            reward=payload.get("reward", 0.01),
            messages=obs_data.get("messages", [])    # FIX: Added the missing messages array
        )




        return StepResult(
            observation=observation,
            reward=payload.get("reward", 0.01),
            done=payload.get("done", False),
        )

    def _parse_state(self, payload: Dict) -> ConstraintState:
        """
        Parse server response into State object.
        """
        if isinstance(payload, str):
            raise ValueError(f"Server returned an error string instead of JSON: {payload}")
            
        return ConstraintState(
            episode_id=payload.get("episode_id"),
            step_count=payload.get("step_count", 0),  # FIX: Added missing step tracking
            max_steps=payload.get("max_steps", 5)     # FIX: Added missing max step bounds
        )